SARS-CoV-2 transmission role of mask in classroom setting

The University of Wisconsin-Madison has conducted a study showing that wearing facemasks in the classroom setting can be highly effective at reducing the aerosol transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) – the agent that causes coronavirus disease 2019 (COVID-19).

Study: Strategies to minimize SARS-CoV-2 transmission in classroom settings: Combined impacts of ventilation and mask effective filtration efficiency. Image Credit: Syda Productions / Shutterstock

However, the filtration efficiency of facemasks can below if they are not fitted properly, warns David Rothamer and colleagues.

The researchers also demonstrated that classroom ventilation alone did not sufficiently reduce the infection probability, whereas even the use of only moderately effective facemasks did reduce this probability sufficiently.

"The results reinforce the use of properly donned masks to achieve reduced aerosol transmission of SARS-CoV-2 and other infectious diseases transmitted via respiratory aerosol indoors," writes the team.

A pre-print version of the paper is available on the medRxiv* server while the article undergoes peer review.

(a) Classroom space setup with manikins (a) view from the front of the room looking back and (b) from the back of the room looking forward.

Using the Wells-Riley equation to assess aerosol transmission

Since the first cases of SARS-CoV-2 were identified in Wuhan, China late last year (2020), researchers have increasingly recognized the long-range airborne route of viral transmission and the need for effective measures to block this transmission mode.

A common approach for assessing long-range airborne transmission (referred to hereafter as aerosol transmission), uses the Wells-Riley equation to relate aerosol concentrations to infection probability.

This approach has already been widely applied in studies of SARS-CoV-2, particularly in the context of super-spreader events.

The researchers say the application of the Wells-Riley equation is useful for risk assessment and the planning of interventions to reduce the risk of disease transmission.

"One of the aims of this paper is to provide recommendations that, when implemented, can decrease the likelihood of COVID-19 transmission in traditionally high occupancy spaces such as classrooms," they write.

What did the researchers do?

The team applied the Wells-Riley equation to evaluate the effect of ventilation, mask filtration, and a combination of the two on aerosol SARS-CoV-2 infection probability in the classroom setting.

Images of masks installed on a manikin for filtration testing (a) 4-layer knit cotton mask, (b) EOC mask, (c) procedure mask, and (d) surgical mask

Related Stories

• Loss of taste and smell may be the most reliable COVID-19 symptoms for digital surveillance
• SARS-CoV-2 spike-antibody binding strength and hydrogen bond numbers are temperature dependent, study finds
• Researchers find a correlation between consistent mask-wearing and improved well-being

A polydisperse neutralized salt (NaCl) aerosol that was generated in a size range consistent with SARS-CoV-2-containing bioaerosols was used as a safe surrogate for measurements.

The mask effective filtration efficiency was tested by seeding a classroom with the NaCl aerosol and sampling concentrations of the aerosol through four different mask types that had been fitted to manikins with and without using mask fitters.

Two of the masks were washable reusable masks. One was made of 4-layers of knit cotton, and the other was made of 3-layers of non-woven spun-bond polypropylene.

The other two masks were disposable. One was a common single-use disposable mask (referred to hereafter as procedure mask), and the other was an ASTM F2100 level-2 surgical mask.

The importance of masks fitting properly

Measurements of the mask's effective filtration efficiency demonstrated the importance of masks being fitted properly. Poorly fitting masks exhibited filtration efficiencies that decreased by as much as a factor of six. The estimated leakage rate for most of the poorly fitted masks was typically more than 50%.

The analysis also found that the knit-cotton mask was only able to achieve an effective filtration efficiency of 26%, even when a mask fitter was used.

In all other cases, the use of a mask fitter significantly improved the effective filtration efficiency, with the exception of the polypropylene mask, which achieved a good fit without a mask fitter. In the case of the procedure mask, the use of a mask fitter achieved effective filtration efficiencies of almost 95%.

Classroom ventilation alone was insufficient

The study also suggested that classroom ventilation alone was not sufficient to achieve infection probabilities of less than 1%.

On the other hand, the use of moderate-to-high effective filtration efficiency masks by all individuals (manikins) present significantly reduced the infection probability.

Depending on the type of mask and whether a mask fitter was used, infection probability was reduced by 5-, 10- or even more than 100-fold.

The team says infection probabilities of less than 0.1% and even lower than 0.0001% could be reached with the use of masks and mask fitters alone.

What does the team advise?

Rothamer and colleagues say the results reinforce the use of properly donned masks to achieve reduced aerosol transmission of SARS-CoV-2.

"The results specifically emphasize the large potential for effective mask-wearing and improved masks, or use of mask fitters, to greatly reduce infection probabilities," concludes the team.

*Important Notice

medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.

Journal reference:

• Rothamer D, et al. Strategies to minimize SARS-CoV-2 transmission in classroom settings: Combined impacts of ventilation and mask effective filtration efficiency. medRxiv, 2020.  https://www.medrxiv.org/content/10.1101/2020.12.31.20249101v1

OBESITY

What Causes Obesity?

"What causes a person to become obese?"

Obesity occurs when, over a long period of time, the amount of food we put into our bodies each day is not used. In essence, this means that there consistently is more energy going in, than out. That energy has to go somewhere, so our bodies store it as fat.

Energy In vs Energy Out Equation

ENERGY "IN" MORE THAN ENERGY "OUT" = WEIGHT GAIN.

ENERGY "IN" LESS THAN ENERGY "OUT" =WEIGHT LOSS.

We all overindulge every now and then, and it isn’t this occasional overeating that causes obesity; obesity is caused when we overdo it most days, for a sustained period of time.

Unfortunately, we live in an environment that encourages us to eat and discourages us to be active, making it very easy to gain weight.  

Have a think about it…

Food is readily available, 24 hours a day, 7 days a week Portion sizes and plates are much bigger than they have been before we can get almost anywhere without having to walk or use a bikeTVs, computers and mobile phones encourage a more sedentary lifestyle.

Smoking Ban Reduces Childhood Asthma Hospital Admissions

September 16, 2010 — A ban on smoking in public places in Scotland, instituted in March 2006, has reduced the rate of hospital admissions for childhood asthma, new research findings suggest.
Daniel Mackay, PhD, from the University of Glasgow, in Scotland, and colleagues reported the findings in the September 16 issue of the New England Journal of Medicine.
According to the researchers, the Smoking, Health and Social Care (Scotland) Act banned smoking in all enclosed public places and workplaces in Scotland as of March 26, 2006.
"The legislation has been extremely successful in its primary aim of reducing exposure to environmental tobacco smoke in public places, such as bars," the authors note. In addition, the legislation has reduced exposure of children to environmental tobacco smoke, despite concerns of smoking being displaced to the home, but it is unclear whether the risk for childhood asthma has also decreased.
The researchers collected routine hospital administrative data and ascertained all hospital admissions for asthma in Scotland from January 2000 through October 2009 among children younger than 15 years.
Before the smoking ban, asthma admissions were increasing by an average of 5.2% per year (95% confidence interval [CI], 3.9% - 6.6%). After the ban, the rate of admissions decreased by 18.2% per year relative to the rate on March 26, 2006 (95% CI, 14.7% to 21.8%; P < .001). Rates were reduced both in preschool and school-age children.
Various factors including age group, sex, urban or rural residence, region, or quintile of socioeconomic status had no effect on the outcome.
Limitations of the study include that only exacerbations severe enough to warrant hospitalization were included. In addition, information regarding individual smoking status was not available; therefore, whether the observed reduction in asthma was a result of reduced exposure to environmental tobacco smoke in the home, reduced exposure to environmental tobacco smoke in public places, a reduction in active smoking among school-age children, or an unrelated cause cannot be determined.
"After the introduction of comprehensive smoke-free legislation, there was a reduction in the incidence of asthma among people who did not have occupational exposure to environmental tobacco smoke," the authors conclude.
They add that the "overall exposure of children to environmental tobacco smoke, measured objectively with the use of salivary cotinine concentrations, has fallen since the implementation of the Scottish legislation."
The study was supported by a project grant from National Health Services Health Scotland. One author reports individual employment by National Health Services Scotland; another chairs the Committee on Medical Effects of Air Pollution for the UK Department of Health. The other authors have disclosed no relevant financial relationships.
N Engl J Med. 2010;363:1139-1145.

Nearly Half of Infected US Gay and Bisexual Men Unaware They Have HIV

September 24, 2010 — One in 5 gay and bisexual men in major cities in the United States is infected with HIV, and nearly half — 44% — do not know their status. Most unaware are young and minority men who have sex with men (MSM), according to a new analysis published in the September 24 issue of the Morbidity and Mortality Weekly Report.
"[MSM] are at increased risk for infection with [HIV]," write A. Smith, MPH, and colleagues from the Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, US Centers for Disease Control and Prevention (CDC). "In 2006, 57% of new HIV infections in the United States occurred among MSM."
The CDC uses the National HIV Surveillance system (NHBS) to monitor prevalence and trends in HIV-related risk behaviors, HIV testing, and use of HIV prevention services among high-risk populations. In the current report, the authors summarize NHBS data from 2008.
From January to December 2008, 8153 MSM from 21 cities were interviewed and tested for HIV. The study found that the overall prevalence of HIV was 19%.
Non-Hispanic blacks had the highest prevalence (28%), followed by Hispanics (18%), non-Hispanic whites (16%), and persons who were multiracial or of other race (17%).
Forty-four percent of those infected with HIV were unaware of their status. Black MSM with HIV were least likely to be aware of their infection (59%), followed by Hispanic MSM (46%) and white MSM (26%).
The study also found that although young men, aged 30 years or younger, had a lower HIV prevalence than older men, they were much more likely to be unaware of their HIV infection. Among men aged 18 to 29 years who had HIV, 63% were unaware vs 37% of men aged 30 years and older.
Also among young men, MSM of color were less likely than their white counterparts to know they were infected with HIV. Among blacks aged 30 years or younger, 71% were unaware of their status compared with 63% of young Hispanic MSM and 40% of young white MSM.
The study also found a strong link between socioeconomic status and HIV infection in MSM. The prevalence of HIV infection increased as education and income decreased, as did awareness. These findings are similar to those found in recent NHBS research among homosexuals, the authors report.
Men who know their current HIV infection status can be referred to appropriate medical care and prevention services. Once they are linked to prevention services, they can learn ways to avoid transmitting HIV to others, the authors note, adding that efforts to reach out to young and minority MSM should be increased to promote testing for HIV.
The authors also note limitations of their report. Because interviewers conducted the surveys, positive HIV status might have been underreported. Also, because the findings are limited to men who frequented bars, dance clubs, and other MSM venues, they may not be representative of results for all MSM.
"The high proportion of MSM unaware of their HIV infection continues to be a serious public health concern, because these MSM account for the majority of estimated new HIV transmissions in the United States," the author write in their concluding remarks. "The 2008 NHBS data show that MSM remain a key target of strategies to reduce HIV incidence and decrease racial and socioeconomic disparities in the United States."
"This study's message is clear: HIV exacts a devastating toll on [MSM] in America's major cities, and yet far too many of those who are infected don't know it," Kevin Fenton, MD, director of the CDC's National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, said in a statement. "We need to increase access to HIV testing so that more MSM know their status, and we all must bring new energy, new approaches, and new champions to the fight against HIV among [MSM]."
The authors have disclosed no relevant financial relationships.
Morb Mortal Wkly Rep. 2010;59:1201-1207

Depression Plus Heart Disease a Particularly Lethal Combination

September 16, 2010 — Patients who have both coronary heart disease (CHD) and depression have a significantly higher risk of dying than patients who have just 1 of these conditions, according to new research published online September 16 in Heart.
Compared with patients without depression and CHD, the risk for all-cause mortality was 3 times higher, and the risk for cardiovascular disease mortality 4 times higher, in patients who had both, after adjusting for age and sex, report Hermann Nabi, MD, from Hôpital Paul-Brousse, Villejuif, Paris, France, and colleagues.
"This study provides further evidence that the relationship between depression and morbidity–mortality is real," Dr. Nabi told Medscape Medical News.
Depression and mortality have been studied separately in patients with CHD and in healthy patients, but this does not allow comparisons across risk-factor groups according to depression and CHD status.
In the study, Dr. Nabi and his team examined the effects of both on mortality in 5936 middle-aged men and women whose mental and physical health were followed-up for a mean of 5.6 years.
The study population was part of the Whitehall II cohort study, a longitudinal study established in 1985 to examine the effect of social and economic factors on the long-term health of 10,308 civil servants who were aged between 35 and 55 years at the start of the study.
Of the 5936 individuals, 170 died during follow-up; 47 of those deaths were from cardiovascular disease.
The analysis showed that the prevalence of depression was 14.9%, and participants with a history of CHD were more likely to have depressive symptoms (20% vs 14%; P = .001) than those without CHD.
The age- and sex-adjusted hazard ratios for all-cause mortality were 1.67 (P < .05) for participants with CHD only, 2.10 (P < .001) for those with depressive symptoms only, and 4.99 (P < .001) for those with both CHD and depressive symptoms compared with participants who were free of both conditions.
Need for a More Integrated Approach
The study findings have implications for research and clinical practice, Dr. Nabi said.
"For research, this study shows that the mechanisms underlying the association between depression and adverse health outcomes such as mortality are still in need of comprehensive studies."
For clinical practice, it implies the need for a more integrated approach in the healthcare system and a shift toward a more "mind–body medicine' approach.
An important step would be to identify cardiac patients who also have depression, he said.
"In this study, the depression worsened heart disease, because we observed that participants with both depression and heart disease were at increased risk for death when compared with those with heart disease only. So we should identify those cardiac patients who have clinically significant depressive symptoms."
Dr. Nabi expressed the wish that his study findings will prompt clinicians to be aware of and look for depression in their patients with heart disease.
"Even though there is no consensus at the moment, healthcare professionals should screen and treat, or refer to treatment. Simple screening tools exist, and [clinicians] should refer their depressed patients, particularly if an adequate referral for systematic depression assessment and treatment is readily available."
He also discussed some limitations of the study.
"This study is based on a cohort of civil servants and did not include blue-collar workers, unemployed, or individuals with precarious jobs. This may have underestimated the magnitude of associations observed in our study because of the prevalence of depression and the mortality rate is higher in these latter individuals. Thus, it is reasonable to assume that the effect of depression would be greater in studies including various populations."
Randomized Trial Required
"This paper is adding to a literature that is imperfect. It makes you feel more confident about the literature," Alexander H. Glassman, MD, chief of clinical psychopharmacology at New York State Psychiatric Institute and professor of psychiatry at Columbia University, New York City, commented to Medscape Medical News.
"There are literally a hundred, maybe more, studies indicating that depression and heart disease are related," Dr. Glassman, who was not part of the current study, noted. "There are a handful of studies that do not find a relationship, but they are vastly outnumbered by the ones that have found a relationship."
However, he pointed out, just because there is an association that does not mean one condition causes the other. The way to prove cause would be with a randomized controlled trial.
"It's very easy to think depression is increasing the risk or is a cause of subsequent heart disease. And let me say, I think it is," said Dr. Glassman, who led the placebo-controlled Sertraline Antidepressant Heart Attack Randomized Trial (SADHART), as reported by Medscape Medical News.
SADHART found that patients hospitalized for acute coronary syndrome who also have major depression are twice as likely to die within 7 years if their depression did not significantly improve.
"The best way to know for sure would be to do a randomized trial on the treatment for depression with a placebo control. If you reduced the depression and those people with an antidepressant effect had a lower mortality, then you would have unequivocal evidence that depression is causing death, because by getting rid of it, you reduce the chance of dying."
The study was funded by the Medical Research Council, British Heart Foundation, Health and Safety Executive, Department of Health, National Heart Lung and Blood Institute, National Institute on Aging, Agency for Health Care Policy Research, and John D. and Catherine T. MacArthur Foundation Research Networks on Successful Midlife Development and Socio-economic Status and Health. Dr. Nabi has disclosed no relevant financial relationships. Dr. Glassman reports financial relationships with Pfizer Inc.
Heart. Published online September 16, 2010.

Women With Low Sexual Arousal May Have Symptom Changes With Placebo Treatment

September 17, 2010 — A large proportion of women with female sexual arousal disorder (FSAD) have clinically significant symptom changes after receiving placebo, according to the results of a secondary data analysis from a randomized controlled trial reported online September 16 in the Journal of Sexual Medicine.
"In clinical trials of drug treatments for women's sexual dysfunction, placebo responses have often been substantial," write Andrea Bradford, PhD, from Baylor College of Medicine in Houston, Texas, and Cindy M. Meston, PhD, from the University of Texas at Austin. "However, little is known about the clinical significance, specificity, predictors, and potential mechanisms of placebo response in sexual dysfunction."
The goal of the study was to evaluate the characteristics and predictors of sexual function outcomes in 50 women with FSAD who were randomly assigned to the placebo group of a 12-week, multisite, controlled pharmaceutical trial. Magnitude, domain specificity, and clinical significance of sexual function scores were evaluated at baseline and at 4, 8, and 12 weeks (after study completion).
Change with time in sexual function outcomes was assessed in relationship to several variables, including age and symptom-related distress at baseline, as well as changes in frequency of sexual behavior during the trial. The primary study endpoint was the total score on the Female Sexual Function Index.
"It's important to note that, even though these women received placebo, they all had an opportunity to talk to a health provider about their difficulties and were asked to closely monitor their sexual behavior and feelings over a 12-week period," Dr. Bradford said in a news release. "Just taking part in this study probably started some meaningful conversations."
Approximately one third of women receiving placebo had a clinically significant magnitude of change after study completion, with similar effect sizes across multiple aspects of sexual function. Although symptom improvement was strongly associated with the frequency of satisfying sexual encounters (SSEs) during treatment, there was significant variation between participants in the association between frequency of sexual encounters and outcome.
"Our study shows that even a limited intervention can have a positive effect in many women with sexual dysfunction," Dr. Bradford said. "This comes as no surprise to sex therapists, but it does suggest a need to investigate behavioral factors more closely in clinical trials."
Limitations of this study include observational design, precluding determination of causality; and the possibility that SSE frequency was just a proxy for another variable, such as changes in general relationship functioning. In addition, the retrospective analysis prevented direct manipulation of variables of interest, and it is not known whether trial participants who received no treatment would have reported the same effects as participants who received placebo.
"A substantial number of women experienced clinically significant improvement in sexual function during treatment with placebo," the study authors write. "Changes in sexual behavior during the trial, more so than participant age or symptom severity at baseline, appeared to be an important determinant of outcome. Contextual and procedural aspects of the clinical trial may have influenced outcomes in the absence of an active drug treatment."
Eli Lilly/ICOS shared the data set used in this study. This study was supported in part by the Houston VA HSR&D Center of Excellence. The views expressed in the journal article are those of the study authors and do not necessarily represent the views of the Department of Veterans Affairs. Drs. Bradford and Meston have disclosed no relevant financial relationships.
J Sex Med. Published online September 16, 2010.

Weight Control and Exercise Could Prevent 20% of Colon Cancer

September 16, 2010 — Around 20% of colon cancer in European countries could be prevented if the whole population managed to reach optimum levels of weight and physical activity, suggest new projections.
The data are reported in the September issue of the European Journal of Cancer, which is dedicated to cancer prevention.
An increasing proportion of the European population now has a body mass index (BMI) higher than 25 kg/m², and few Europeans are engaging in the amounts of physical activity recommended by current guidelines (at least 30 minutes of moderate-intensity activity 5 or more days a week), the researcher note.
The researchers set out to predict what would happen if the European population managed to maintain a mean BMI of 21 kg/m² and if all countries had a level of physical activity similar to that seen in the Netherlands, where both cycling and walking are popular.
They used the PREVENT statistical modeling method, which was developed at Erasmus University in the Netherlands and is frequently used in the European Union's EUROCADET project.
"We know that large numbers of colon cancer cases could be avoided by reducing exposure to risk factors," said senior author Andrew Renehan, PhD, FRCS, FDS, from the School of Medicine, University of Manchester, United Kingdom. And 2 of the most easily controllable risk factors are physical inactivity and excess weight, he added.
"The predictive modeling is beginning to tease out the independent relevance of each of these factors in the prevention of colon cancer," he said in a statement.
"Preventing weight gain and encouraging weight reduction seem to be most beneficial in men, but for women a strategy with a greater emphasis on increasing physical activity would be more effective," he explained.
Colon Cancer Increasing
Colon cancer rates are increasing in Europe; they have been on the rise since 1975. It is the second most common cancer in Europe and the second most common cause of cancer death, the researchers note.
In a previous study, Dr. Renehan and colleagues attributed the increasing rates of all cancers to increasing obesity in European countries. They estimated that in 2008, new cancers attributed to excess body weight affected 3.2% of women and 8.6% of men; this was an increase from the estimates for 2002, which projected that excess weight was related to new cancers in 2.5% of men and 4.1% of women.
Those data were presented at the 2009 meeting of the European Cancer Organization, and reported by Medscape Medical News at the time.
"People in Europe are gaining weight," Dr. Renehan said at the time, "and it is projected to keep rising."
In the new study, the researchers used the computer model to look at what would happen if Europeans continued to grow fatter, using a hypothetical scenario in which obesity levels increased at the same rate as they have in the United States. They predicted that this would lead to an increase in the number of new colon cancer cases of between 0.7% and 3.8%, depending on the European country.
Then they hypothesized a scenario in which Europeans managed to control their weight and managed to achieve an optimum BMI of 21 kg/m². They calculated that by the year 2040, this weight-control strategy would prevent between 2% and 18% of colon cancer cases across the countries they studied. The benefits were much higher for males (13.5% to 18%) than for females (2.3% to 4.6%), and most benefit would be seen in British males (in whom 18% of new colon cancer cases could be prevented).
This "underlines the importance of stopping and reversing the ongoing increase in overweight and obesity prevalence," the authors note.
When the team considered physical activity, they found that the Netherlands had the highest rates, which they attributed to a high frequency of bike use, often as a means of transportation. They also found high levels of walking.
Using the Netherlands as the ideal, the researchers predicted what would happen if other countries adopted the same amount of physical activity. They found that overall, 17.5% of new colon cancer cases could be prevented by 2040, with the most benefit in Spanish females (in whom 21% of new colon cancer cases could be prevented).
"We can safely say that increasing physical activity across Europe to the level already achieved in the Netherlands, where everyone cycles, would be of substantial benefit," said coauthor Jan-Willem Coebergh, MD, PhD, from Erasmus University.
"In summary, the changes in physical activity and/or mean levels of overweight in the selected European populations would result in quite substantial effects on future colon cancer rates," the authors conclude.
The researchers have disclosed no relevant financial relationships.
Eur J Cancer. 2010;46:2605-2616.

Resident Physicians Have High Rates of Presenteeism (Working While Sick)

September 16, 2010 — Although there have been major residency reforms during the past decade, rates of presenteeism (working while sick) among resident physicians are high and similar to rates seen in 1999, according to the results of a research letter reported in the September 15 issue of the Journal of the American Medical Association.
"Despite recent Centers for Disease Control and Prevention guidelines urging health care personnel with flu-like illness to avoid working, presenteeism (working while sick) is prevalent among health care workers," write Anupam B. Jena, MD, PhD, from Massachusetts General Hospital in Boston, and colleagues. "Ill health care workers can endanger patients and colleagues due to decline in performance or spread of disease. Resident physicians may face unique pressures to work when sick and lack time to seek health care."
The study goal was to evaluate self-reported presenteeism rates and associated factors among residents in a sample of programs selected for varied geographic, size, and governance characteristics. A 50-item survey was administered anonymously in August 2009 to 744 residents in postgraduate year (PGY) 2 and 3 in general surgery, obstetrics/gynecology, internal medicine, and pediatrics at 35 programs in 12 hospitals regarding presenteeism during the prior year. Overall response rate was 72.2% (range among hospitals, 48% - 100%).
More than half of responders (57.9%; 95% confidence interval [CI], 53.6% - 62.1%) reported working at least once while sick in the previous year, and nearly one third (31.3%; 95% CI, 27.2% - 35.2%) reported working more than once while sick. More than half (52.9%; 95% CI, 48.5% - 57.1%) reported having insufficient time to visit a physician during the previous academic year.
Presenteeism was reported more often during PGY-2 (62.3%; 95% CI, 57.1% - 68.4%) than during PGY-1 (51.7%; 95% CI, 45.6% - 57.9%; P = .01). Sex, specialty, or medical school location did not affect reported rates of presenteeism or of having time to see a physician. Presenteeism rates did not vary significantly by hospital response rate or across hospitals, except for 1 outlier hospital in which 100% of residents reported working when sick.
"Despite major residency reforms over the last decade to ensure resident and patient health, rates of resident presenteeism were high and similar to rates observed in 1999," the study authors write. "The higher rate of reporting working when ill among PGY-2 vs. PGY-1 residents may reflect a greater responsibility toward patient care, consistent with higher presenteeism rates among workers who believe their duties are not easily substituted. The lack of factors associated with presenteeism suggests it may be pervasive."
Limitations of this study include reliance on self-report, lack of distinction between infectious and noninfectious illness, and potential bias associated with H1N1 influenza cases during survey development.
"Residents may work when sick for several reasons, including misplaced dedication, lack of an adequate coverage system, or fear of letting down teammates," the study authors conclude. "Regardless of reason, given the potential risks to patients related to illness and errors, resident presenteeism should be discouraged by program directors."
This study was funded by the Accreditation Council for Graduate Medical Education. Several of the study authors report various financial relationships with the Agency for Health Care Research and Quality, the National Institutes of Health, the Accreditation Council for Graduate Medical Education, the American Board of Internal Medicine Foundation, and/or the Institute of Medicine.
JAMA. 2010;304:1166-1168.

Swimming Pool Chemicals May Carry Cancer Risk

September 15, 2010 — Swimming in indoor pools may result in respiratory effects and induce DNA damage that could lead to cancer, according to new research that examined the impact of byproducts of pool disinfection.
But the researchers emphasize they are not suggesting anyone get out of the pool. "We do not say stop swimming," says researcher Manolis Kogevinas, MD, PhD, professor of epidemiology at the Centre for Research in Environmental Epidemiology in Barcelona. "We should keep a clear message that swimmers should keep swimming."
The research findings, he tells WebMD, are a message to the industry that ''the positive effects of swimming could be increased by reducing the chemicals."
Industry experts and pool researchers agree. "It's good that research is being done in this area,'' says Thomas Lachocki, CEO of the National Swimming Pool Foundation, an educational nonprofit organization based in Colorado Springs, Colo.  The research is published online in the journal Environmental Health Perspectives.
Swimming and Health Risks: A Closer Look
''We have been doing research on chemicals in water -- not swimming pools [specifically] -- for quite some time," Kogevinas says. More recently, he and his colleagues have focused more intently on indoor swimming pool water. "Chemicals are produced when you put chlorine in water," he says. Chlorine reacts, for instance, to urine, cosmetics, and other substances typically found in swimming pools.
The researchers wanted to characterize these disinfection byproducts, or DBPs, in an indoor pool environment. Other studies have linked DBP exposure in drinking water to a risk of bladder cancer and other problems.
In the first of three new studies published in the journal, the researchers evaluated 49 healthy adults after they swam for 40 minutes in an indoor chlorinated pool, looking for biomarkers linked to cancer.
"What we found is by analyzing blood samples and urine samples, we have an increase in risk markers related to cancer," Kogevinas tells WebMD.
Exposure to the pool water was associated with a five-fold increase in one of the markers, he says. But that does not mean swimmers are doomed to get cancer, he stresses.
"This doesn't mean at all that swimmers have a five times increased cancer risk," he says. "It simply means that after swimming for 40 minutes in a chlorinated pool, you get an increase in this marker in the blood that in other studies has been associated with future cancer risk."
Swimming and Respiratory Effects
In a second study, Kogevinas and his colleagues focused on respiratory effects of exposure to indoor pool water.
"We compared markers of lung injury before and after swimming," he says, evaluating 48 swimmers this time, from the same group as in the first study.
They found changes in just one blood marker, a slight increase in one known as CC16. The increase, the researchers say, is due to the exercise itself in addition to the DBP exposure.
''Some studies have suggested a link with swimming and asthma," Kogevinas says. "We found [only] one of many [respiratory] biomarkers [had] a small increase."
Swimming Pool Chemicals: What's in Pool Water?
In a third study, the researchers looked at water and air samples from two indoor pools. "We shipped them to the EPA [U.S. Environmental Protection Agency]," Kogevinas says.  They found more than 100 DBPs in the pool water, some not identified before.
''Many are the same chemicals we find in tap water," he tells WebMD.  "Some have been identified in experimental studies, animal studies, to be harmful."
The bottom line? "Pool water is not worse or better than tap water," he says, when it comes to byproducts. Only in the pool, he adds, "swimmers get a massive dose."
Swimming Pools and Health Risks: Second Views
Experts from the swimming pool industry say research is crucial. "It's important we find ways to reduce exposure to potentially hazardous chemicals in pools," Lachocki says.
Even so, he calls the three studies "limited" because of some shortcomings. He wanted more information on how the pools studied were managed and what standards were used to keep the pools maintained.
"The question is, were the pools studied on the end of the spectrum of fabulously well taken care of, or not so fabulously?" he says.
The conclusion of the research that the pool water is no more hazardous than drinking water doesn't tell people if that is representative of most pools or just the ones studied, Lachocki says.
Another limitation is the small number of swimmers studied, he says.
What's a Swimmer to Do?
Lachocki agrees that no one should give up swimming as a result of the research. "Swimming continues to be ideal for an aging population and for a sedentary population," he says.
People who swim in indoor pools can check out the pool first, he tells WebMD. Ask, for instance, if the pool has certified operators, which means they have had training in how best to disinfect a pool.
His foundation trains certified operators. "There should be a certificate on the wall, showing the people who operate the pool are certified."
Swimmers can buy test strips, widely available at pool supply stores, and test the water themselves, he says. Swimmers can also ask the pool operators to show them the maintenance records proving the pool is maintained properly, he says.
Kogevinas suggests that people who swim in indoor pools follow rules, such as not urinating in the pool and showering before swimming.
SOURCES:
Manolis Kogevinas, MD, PhD, professor of epidemiology, Centre for Research in Environmental Epidemiology, Barcelona, Spain.
Thomas Lachocki, PhD, CEO, National Swimming Pool Foundation, Colorado Springs, Colo.
Kogevinas, M. Environmental Health Perspectives, online Sept. 12, 2010.
Font-Ribera, L. Environmental Health Perspectives, online Sept. 12, 2010.
Richardson, S. Environmental Health Perspectives, online Sept. 12, 2010.

NSAID Use Associated With Future Stroke in Healthy Population

September 8, 2010 (Stockholm, Sweden) — Short-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) was associated with an increased risk of stroke in a Danish population study including only healthy individuals.
Presenting the study at last week's European Society of Cardiology (ESC) 2010 Congress, Dr Gunnar Gislason (Gentofte University Hospital, Hellerup, Denmark) said the results could have "massive public-health implications."
"First we found an increased risk of MI with NSAIDs. Now we are finding the same thing for stroke. This is very serious, as these drugs are very widely used, with many available over the counter," Gislason told heartwire . "We need to get the message out to healthcare authorities that these drugs need to be regulated more carefully."
Cochair of the session at which the study was presented, Dr Robert Califf (Duke Clinical Research Institute, Durham, NC), agreed that the results raised a major public-health issue, especially in the US, where many NSAIDs were available without a prescription.
For the current study, Gislason and colleagues examined the risk of stroke and NSAID use in healthy individuals living in Denmark. He explained to heartwire that information on each individual in the Danish population is kept in various national registries. His team started with the whole population of Denmark aged over 10 years. To select just the healthy individuals, they excluded anyone admitted to the hospital within the past five years or those prescribed chronic medications for more than two years. This left a population of around half a million, who were included in the study. By linking to prescribing registries, the researchers found that 45% of these healthy individuals had received at least one prescription for an NSAID between 1997 and 2005. They then used stroke data from further hospitalization and death registries and estimated the risk of fatal and nonfatal stroke associated with the use of NSAIDs by Cox proportional-hazard models and case-crossover analyses.
Results showed that NSAID use was associated with an increased risk of stroke. This increased risk ranged from about 30% with ibuprofen and naproxen to 86% with diclofenac.
Risk of Stroke With Various Nsaids

NSAID	HR (95% CI) for risk of stroke
Ibuprofen	1.28 (1.14–1.44)
Diclofenac	1.86 (1.58–2.19)
Rofecoxib	1.61 (1.14–2.29)
Celecoxib	1.69 (1.11–2.26)
Naproxen	1.35 (1.01–1.79)

Gislason noted that there was also a dose-relationship found, with the increased risk of stroke reaching 90% (HR 1.90) with doses of ibuprofen over 200 mg and 100% (HR 2.0) with diclofenac doses over 100 mg. He pointed out that the results were particularly striking, given that this study was conducted in healthy individuals.
He conceded that his results could have some confounding but noted that the data were controlled for age, gender, and socioeconomic status and the patient population did not include those with chronic diseases. "We also have to think about the degree of confounding needed to nullify risk. It would have to increase risk four- to fivefold, which is very unlikely," he commented.
He said he did not find the results that surprising in view of the accumulating evidence of increased MI risk with these drugs, adding that the mechanism was probably the same. There have been several hypotheses about the mechanism linking NSAIDs with cardiovascular events, including increased thrombotic effect on platelets, the endothelium, and/or atherosclerotic plaques; increasing blood pressure; and effect on the kidneys and salt retention.
Gislason told heartwire that there is reluctance among the medical profession to limit the prescribing of these drugs. "The problem is that we don't have randomized trials, and it is very hard to change the habits of doctors. They have been using these drugs for decades without thinking about cardiovascular side effects."
He also stressed that the public needs to be protected by not allowing NSAIDs to be bought without a prescription. He has had some success in this regard in Denmark at least, where diclofenac became available over the counter recently, but after some of the MI data came out, Gislason's group campaigned the health authorities, and it has now become a prescription-only drug again. But he noted that many more NSAIDs are available over the counter in the US.
He believes the harmful effects of these agents are relevant to huge numbers of people. "If half the population takes these drugs, even on an occasional basis, then this could be responsible for a 50% to 100% increase in stroke risk. It is an enormous effect."
These results have been partly published in Circulation: Cardiovascular Quality and Outcomes earlier this year [1]. Gislason told heart wire that the novelty of the results presented at the ESC meeting was that "we had further analyzed our data regarding specific stroke and looked at the risk of ischemic stroke, and we confirmed that the risk of ischemic stroke was substantially elevated." He added: "We are in the process of analyzing these data related to time to risk and the effect of duration of treatment on stroke risk."

Metformin Might Prevent Colorectal, Lung Cancers

September 3, 2010 — The chance observation that diabetes patients taking metformin have a 40% reduced risk for cancer triggered intense research interest in this old off-patent drug.
Data from a small clinical trial and from an animal study reported in the September issue of Cancer Prevention Research suggest that metformin might suppress the development of precancerous colorectal lesions in humans and prevent tobacco-induced lung cancers in mice. The drug appears to alter cellular energy metabolism in a way that is particularly bad for cancers and precancerous cells. It is also attractive because it is relatively nontoxic.
During a press briefing organized by the American Association for Cancer Research to discuss the metformin data, Michael Pollak, MD, from McGill University in Montreal, Quebec, said that the new studies are important because they indicate the usefulness of metformin as a preventive agent. Dr. Pollak wrote a review of metformin and other biguanides in oncology that appears in the same issue of Cancer Prevention Research.
"Unlike chemotherapy or radiotherapy, which are intended to kill cancer cells in a directly toxic manner, metformin appears to target the cancer in a more subtle way, which involves cancer energetics. It also may act in some patients, especially diabetic cancer patients, by reducing levels of hormones that can stimulate cell growth, including insulin itself," Dr. Pollak said.
In the first human trial of metformin as a cancer preventive, Kunihiro Hosono, MD, and colleagues from the Yokohama City University School of Medicine in Japan report that nondiabetic patients randomized to 1 month of low-dose of metformin (250 mg/day) had a significant decrease in the mean number of rectal aberrant crypt foci (ACF), an endoscopic surrogate marker of colorectal cancer.
The researchers randomized 12 nondiabetic patients with ACF to treatment with metformin and 14 to no treatment. After 1 month, the metformin patients not only had fewer ACFs, they also had significant decreases in the proliferating cell nuclear antigen index.
Dr. Hosono and colleagues write that "this first reported trial of metformin for inhibiting colorectal carcinogenesis in humans provides preliminary evidence that metformin suppresses colonic epithelial proliferation and rectal ACF formation in humans, suggesting its promise for the chemoprevention of colorectal cancer."
Low-dose metformin did not cause any adverse effects, such as lactic acidosis, hypoglycemia, or diarrhea in this study.
In related work, a research team led by Phillip A. Dennis, MD, and Regan M. Memmott, MD, from the National Cancer Institute (NCI) Medical Oncology Branch in Bethesda, Maryland, studied metformin for prevention in a mouse model of smoking-related lung cancer. They exposed mice to the tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and then treated the mice with metformin in drinking water.
The researchers expected that a specific target (the rapamycin or mTOR pathway, an early event in tobacco-induced lung cancer) would be inhibited by metformin.
"After about 10% of the mouse lifespan — about 12 weeks — with the highest dose in the drinking water, we found a 33% reduction in tumor multiplicity and a 34% reduction in tumor size in the mice. In mice that did not get metformin, 100% got tobacco carcinogen-induced lung tumors," Dr. Dennis said at the press briefing. Overall, metformin reduced lung tumor burden by up to 53% at steady-state plasma concentrations that can be achieved in humans.
Despite this, mTOR was only modestly inhibited, so the researchers moved to intraperitoeal administration to achieve higher dose levels. This showed that metformin activated 5′-AMP-activated protein kinase in liver tissue (but not lung tissue), where it inhibited phosphorylation of the insulin-like growth factor (IGF)-1/insulin receptor. Mice injected with metformin daily for 12 weeks had a 72% reduction in tumor burden.
"We think that metformin was able to inhibit lung tumorigenesis caused by a tobacco carcinogen — when given in drinking water to achieve levels that could be attained in humans and when given by injection — and that the mechanism involves hormone release from the liver. We are planning to move forward to study metformin as a chemopreventive agent in clinical trials," Dr. Dennis said.
Lewis Cantley, MD, from Beth Israel Deaconess Medical Center in Boston, Massachusetts, suggested at the press briefing that metformin might prevent tumors by reducing levels of insulin and IGF-1. He noted that 2 approaches to treating type 2 diabetes (insulin, which increases insulin levels, and metformin, which decreases them) appear to have opposite effects on cancer risk.
Dr. Pollak said that "metformin's effects in animals are similar to those of a brief period of fasting. On a normal diet, metformin fools the liver into thinking it is fasting."
It fell to Dr. Cantley to mention the elephant in the room: metformin is off patent and unlikely to attract pharmaceutical industry support for clinical trials to established the drug as a general cancer preventive. "This will have to have millions of dollars in either private or NCI support," he said.
Dr. Pollak reports consulting for Merck, Novo-Nordisk, Lilly, Pfizer, and Sanofi-Aventis. Dr. Hosono and Dr. Dennis have disclosed no relevant financial relationships. Dr. Cantley is founder of and a consultant for Agios.
Cancer Prev Res (Phila Pa). 2010;3:1049-1052, 1060-1065, 1066-1076, 1077-1083.

Artificially Sweetened Soft Drinks Linked to Preterm Delivery

August 31, 2010 — Daily consumption of artificially sweetened soft drinks may increase the risk for preterm delivery, according to the results of a Danish prospective cohort study reported in the September issue of the American Journal of Clinical Nutrition.
"Sugar-sweetened soft drinks have been linked to a number of adverse health outcomes such as high weight gain," write Thorhallur I. Halldorsson, from Statens Serum Institut in Copenhagen, Denmark, and colleagues. "Therefore, artificially sweetened soft drinks are often promoted as an alternative. However, the safety of artificial sweeteners has been disputed, and consequences of high intakes of artificial sweeteners for pregnant women have been minimally addressed."
The goal of the study was to evaluate the association between consumption of sugar-sweetened and artificially sweetened soft drinks and preterm delivery.
Participants were 59,334 women enrolled in the Danish National Birth Cohort from 1996 to 2002. With use of a food frequency questionnaire, soft drink consumption was evaluated in midpregnancy, and telephone interviews determined covariate information. The main study endpoint was preterm delivery, defined as less than 37 weeks of gestation.
Consumption of artificially sweetened carbonated and noncarbonated soft drinks was associated with an increased risk for preterm delivery (P for trend ≤ .001 for both variables). Compared with women who did not drink artificially sweetened carbonated soft drinks, the adjusted odds ratio (OR) for women who drank at least 1 serving daily was 1.38 (95% confidence interval [CI], 1.15 - 1.65), and the adjusted OR for women who drank at least 4 servings daily was 1.78 (95% CI, 1.19 - 2.66). These associations were noted in normal-weight as well as in overweight women. Increased risk was stronger for early preterm and moderately preterm delivery vs late-preterm delivery.
For sugar-sweetened carbonated or noncarbonated soft drinks, no apparent association with the risk for preterm delivery was observed.
"Daily intake of artificially sweetened soft drinks may increase the risk of preterm delivery," the study authors write. "Further studies are needed to reject or confirm these findings."
Limitations of this study include possible reverse causality, inability to implicate specific artificial sweetener(s), observational design, and unidentified or residual confounders.
"The relative consistency of our findings for carbonated and noncarbonated soft drinks and the absence of an association for sugar-sweetened soft drinks suggest that the content of artificial sweeteners might be the causal factor," the study authors conclude. "However, the replication of our findings in another experimental setting is warranted."
The European Union (EU) Integrated Research Project EARNEST supported this study. The EU project EARNEST receives financial support from the Commission of the European Communities. The Danish National Birth Cohort has been financed by the March of Dimes Birth Defects Foundation, the Danish Heart Association, the Danish Medical Research Council, and the Sygekassernes Helsefond Danish National Research Foundation, Danish Pharmaceutical Association, Ministry of Health, National Board of Health, Statens Serum Institut. The study authors have disclosed no relevant financial relationships.
Am J Clin Nutr. 2010;92:626-633

U.S. Births Decline; Economy to Blame?

August 30, 2010 — The number of babies born in the United States declined an estimated 2.6% in 2009 compared to the previous year, the CDC says. And it may be the result of the downturn in the economy.
The new report, by the CDC’s National Center for Health Statistics, says provisional data indicate that an estimated 4,136,000 babies were born in 2009, compared to 4,247,000 in 2008.
The report also found that:

• Births also dropped in 2008, compared to the previous year, with an estimated 4,251,095 babies born.
• In the preliminary analysis for 2008, births dropped for women under 40, but increased for women 40 and over. The decline in births in 2009 may well be associated with the severe downturn in the U.S. economy, which started late in 2007. But it’s too early to know for sure until more statistics are available.

Preliminary Data
The statistics are contained in National Vital Statistics Reports, a publication of the CDC and its National Center for Health Statistics.
It presents early data from all 50 states and Washington, D.C., plus Puerto Rico, but stresses the statistics are preliminary.
The study also reports that:

• The busiest month for births in 2009 was July, when 369,000 babies were born. In 2008, July also witnessed the greatest number of births, 376,000.
• California had the most live births in both years, 530,659 in 2009, down from 551,592 in 2008.
• The fewest number of births in 2009 occurred in Vermont, where 6,118 live births were recorded. Vermont also had the fewest births in 2008 -- 6,275. California reported the most marriages for the second straight year, 213,922, down considerably from 247,022 in 2008. Washington, D.C., reported the fewest number of marriages in 2009 at 1,892, a significant drop from 2,367 in 2008.

SOURCES:
Tejada-Vera, B. National Vital Statistics Reports, Aug. 27, 2010; vol 58.

Exercise Can Treat Cardiovascular Disease as Well as Prevent It

August 30, 2010 (Stockholm, Sweden) — A series of presentations here at the European Society of 2010 Cardiology Congress emphasized how even moderate regular exercise can reverse the damage of existing heart disease while also preventing it.
In one such study, from a session entitled "Exercise: From leisure activity to a therapeutic option,"Dr Brage Amundsen (Norwegian University of Science and Technology [NUST], Trondheim) explained how his group is learning how to improve heart-failure patients' peak oxygen consumption (VO₂). Low peak VO₂ is a driver of poor prognosis in postinfarction heart-failure patients, he explained. The NUST group has conducted similar studies on the benefits of interval training for patients with metabolic syndrome.
Amundsen's group is preparing the randomized SMARTEX-HF study comparing aerobic interval training with moderate continuous training in about 200 patients. The interval-training regimen is built on four four-minute intervals walking on the treadmill at 90% to 95% of peak heart rate, with three-minute "active pauses"--walking at 50% to 70% of peak heart rate--between each interval. Including warm-up and cool-down periods, the total workout lasts 38 minutes. Patients in the moderate continued-training group will walk continuously at 70% to 75% of peak heart rate for 47 minutes.
Preliminary studies show that patients using the interval regimen improve their peak VO₂by a much larger margin than the moderate continuous-training group and that patients in the interval-training group exhibited reverse left ventricular remodeling, reduction in pro-B-type natriuretic-peptide (proBNP)--a marker of hypertrophy and severity of heart failure--and improvement in left ventricular ejection fraction. In vitro cell studies showed that interval training was associated with a reduction of endothelial-cell volume, and functional measures of single myocytes indicate improvements to muscle contractility and oxygen consumption in the interval group.
"A lot of people think this [high-intensity exercise] must be very hard, so we have to be a bit more realistic and inform the patients that it's not that hard and that anybody can do it," he said.
A Role for Strength Training
In a separate presentation, Dr François Carré (Hôpital Pontchaillou, Rennes, France) described research on a variety of exercise modalities showing that cardiovascular patients benefit from strengthening large muscles in addition to aerobic exercise, so "well-done" resistance training should be encouraged on top of aerobic exercise. His group's research has shown that the benefits of exercise generally far outweigh the risks for cardiovascular-disease patients, but exertion does increase the risk for cardiovascular adverse events, "so the physician must evaluate the individual risk, propose an individual program, and give a good education to the patients."
As well, Dr Rainer Rauramaa (Kuopio Research Institute of Exercise Medicine, Finland) presented research that suggests regular moderate-intensity exercise ought to be considered a "cornerstone" in the treatment of hypertension even if the impact is modest.
Early studies suggested that exercise did not improve resting blood pressure, but a more detailed look at the data showed that genetic factors play a major role in determining the response of a patient's blood pressure to exercise. Rauramaa's group also found that exercise's influence on blood pressure lasts only a few days, so the earlier studies may have simply missed the benefit of exercise by measuring the patients' blood pressure several days after their last exercise. His group found an improvement in carotid intima-media thickness in patients who exercised, but the improvement did not appear until three years into their study.
"There was a clear antiatherosclerotic effect of exercise." He pointed out that the antihypertensive benefits of exercise can be achieved even without weight reduction.

Dr Rainer Hambrecht

Finally, Dr Rainer Hambrecht (HerzzentrumBremen, Germany) presented unpublished results from the PET Multicenter study. As reported by heartwire , that study, showing that 12 months of exercise training was just as good as PCI for myocardial perfusion and symptom relief in patients with stable angina, had to be stopped early due to slow enrollment, but the data from the patients who were enrolled plus the results from a small pilot study show that both strategies improve myocardial perfusion, angina threshold, and exercise capacity. However, only exercise improves endothelial function and slows the progression of disease, because PCI is only a local palliative therapy, while exercise training has an impact on the underlying disease in the entire coronary tree, Hambrecht said.
"I would be happy if I could convince everybody with coronary artery disease to participate in a moderate exercise program," he said. He recommends patients stick to the professional guidelines by exercising three or four times a week, 30 minutes per session, at moderate exertion. He cited previous studies showing that patients who attempt to exceed that effort are at increased risk for potentially lethal arrhythmias.

Black Rice Is Cheap Way to Get Antioxidants

August 27, 2010 — Inexpensive black rice contains health-promoting anthocyanin antioxidants, similar to those found in blackberries and blueberries, new research from Louisiana State University indicates.
"Just a spoonful of black rice bran contains more health promoting anthocyanin antioxidants than are found in a spoonful or blueberries, but with less sugar and more fiber and vitamin E antioxidants," Zhimin Xu, PhD, of Louisiana State University Agricultural Center, says in a news release. "If berries are used to boost health, why not black rice and black rice bran?"
Xu and colleagues analyzed samples of black rice bran from rice grown in the Southern U.S.
He says black rice bran would be a unique and inexpensive way to increase people's intake of antioxidants, which promote health.
Black rice is rich in anthocyanin antioxidants, substances that show promise for fighting cancer, heart disease, and other health problems, Xu says.
He adds that food manufacturers could use black rice bran or bran extracts to boost the health value of breakfast cereals, beverages, cakes, cookies, and other foods.
Black Rice vs. Brown Rice
The most widely produced rice worldwide is brown. Millers of rice remove the chaff, or outer husks, from each grain to make it brown.
White rice is made when rice is milled more than is done for brown rice; the bran is also removed, Xu says.
The bran of brown rice contains high levels of one of the vitamin E compounds known as "gamma-tocotrienol" as well as "gamma-oryzanol" antioxidants.
Many studies have shown that these antioxidants can reduce blood levels of LDL "bad" cholesterol and may fight heart disease.
So black rice bran may be even healthier than brown rice, Xu says.
He and his colleagues also showed that pigments in black rice bran extracts can produce a variety of colors, from pink to black, and may be a healthier alternative to artificial food colorants that manufacturers now add to some foods and beverages.
He writes that several studies have linked some artificial colorants to cancer, behavioral problems in children, and other adverse health effects.
Currently, black rice is used mainly in Asia for food decoration, noodles, sushi, and pudding, and Xu says that he would like to see it eaten by more Americans.
Black rice bran could be used to boost the health value of foods, such as snacks, cakes, and breakfast cereals, Xu and his colleagues suggest.
This study was presented at a medical conference in Boston. The findings should be considered preliminary because they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.
SOURCES:
News release, American Chemical Society.
2010 National Meeting of the American Chemical Society, Boston, Aug. 22-26, 2010.

Pay Growing Faster for Nurse Practitioners Than Physicians

August 25, 2010 — In a sign of their value in a shorthanded clinical workforce, nurse practitioners (NPs) in group practices saw their compensation increase 4.9% last year, outpacing physicians as a whole, according to the Medical Group Management Association (MGMA).
Compensation for primary care physicians rose 2.9% in 2009, the MGMA reports in its latest Physician Compensation and Production Survey: 2010 Report Based on 2009 Data. Specialists took a 4.1% pay cut, although some individual specialties such as dermatology (12.3%) and ophthalmology (7.7%) posted sizable gains.
At $85,706, the median compensation for NPs in 2009 was far less than what primary care and specialist physicians earned — $191,401 and $325,916, respectively — in group practices. Still, NPs are slowly gaining ground. Since 2005, their compensation has risen 21.9% compared with 13.9% for primary care physicians and 2.9% for their specialty counterparts, according to the MGMA.
"We're in demand," said NP Jan Towers, PhD, director of health policy for the American Academy of Nurse Practitioners, about the compensation trend. "NPs don't have any problems getting work."
The job market is so good that it has been able to absorb a tidal wave of new NPs. The ranks of the profession have grown from 82,000 NPs in 2000 to 140,000 today, according to Dr. Towers.
At the same time, Dr. Towers told Medscape Medical News, a 4.9% pay raise in 2009 is not spectacular. "We should be getting more of an increase," she said.
Physician assistants (PAs) are not far behind NPs in their earnings trajectory. Compensation has risen 17.8% for PAs in primary care and 19.8% for those in surgical specialties since 2005. PA pay hikes in 2009 were less impressive, however, at 1.8% and 0.3%, respectively.
NPs Generate More Revenue Relative to Compensation Than Physicians
The current shortage of primary care physicians is creating higher demand for NPs, which in turn increases their compensation, said Justin Chamblee, a consultant with the Coker Group, a practice management consulting firm in Atlanta, Georgia.
By all accounts, this demand promises to grow stronger under healthcare reform, which will extend insurance coverage to 32 million additional individuals through 2019. Healthcare reformers view both NPs and PAs as an economical way to help tend to these newly insured individuals. Licensed to diagnose illness and prescribe medications, NPs, along with PAs, can perform about 80% of the services provided by primary care physicians, with comparable quality, according to a number of published studies.
Dave Duncan, a senior search consultant with the healthcare recruitment firm Cejka Search in St. Louis, Missouri, said medical practices hire NPs to relieve overworked physicians, share call duty, and staff rural clinics. "But it's getting tougher to find these folks," Duncan told Medscape Medical News. One reason is the growing number of retail clinics operated by drug stores, big-box retailers, and health systems, which also hire NPs to treat patients.
NPs can boost the bottom line of a medical practice in several ways, experts say. By assigning simpler medical cases to NPs, physicians can concentrate on the more complex ones, which insurers reimburse at higher rates.
At the same time, a primary care medical practice that traditionally would hire extra physicians to help carry a burgeoning patient workload can get more bang for its buck hiring NPs instead, based on the ratio of compensation to collections — that is, revenue — for the 2 professions. General internists, for example, received a median $197,080 in compensation last year while generating $366,622 in collections, according to the MGMA. In contrast, the ratio of compensation to collections is better for an NP in primary care, at $84,488 to $228,668. Put another way, 2 such NPs would generate more revenue than a single internist, but their combined compensation would be less than the internist's. The same math also works in favor of PAs.

Physicians' Religious Beliefs Influence End-of-Life Decisions

August 26, 2010 — Physicians who describe themselves as nonreligious are almost twice as likely to make decisions that may end a patient's life compared with physicians who described themselves as religious, according to new research.
Clive Seale, PhD, from Barts and the London School of Medicine and Dentistry, in the United Kingdom, reported the findings online August 26 in the Journal of Medical Ethics.
"The relationship of UK doctors' religiosity and ethnicity to actual end-of-life decisions is poorly understood," noted Dr. Seale in his report. "The present study reports findings on these from a nationally representative survey of doctors, using methods that allow for comparison with censuses and surveys of the general UK population."
A total of 8857 UK medical practitioners were mailed an anonymous questionnaire to assess their end-of-life decisions for patients. Of those, 3733 (42.1%) responded, and 2923 reported on the care of a patient who had died. Specialties included were weighted for those in which end-of-life decisions are more common, such as neurology, elderly care, palliative care, intensive care, and general practice.
Physicians who described themselves as "extremely" or "very non-religious" were almost twice as likely to report having taken the kinds of decisions expected or partly intended to end life as were those with a religious belief.
Ethnicity was not related to rates of reporting ethically controversial decisions, although it was related to support for assisted dying/euthanasia legislation. Specialty was strongly related to whether a physician reported having taken decisions expected or partly intended to end life. Physicians in hospital specialties were almost 10 times as likely to report this as palliative care specialists.
The most religious physicians were also significantly less likely to have discussed end-of-life care decisions with their patients than other physicians.
Specialists in the care of the elderly were more likely to be Hindu or Muslim, whereas palliative care physicians were more likely than other physicians to be Christian and white and to state that they were "religious." Overall, white physicians, who were the largest ethnic group, were the least likely to report strong religious beliefs.
These attitudes were reflected in support for assisted dying/euthanasia legislation, with palliative care specialists and those with a strong faith more strongly opposed to euthanasia. Asian and white physicians were less opposed to such legislation than physicians from other ethnic groups.
"Whether religious or non-religious, it would seem advisable that doctors become more aware of how broader sets of values, such as those associated with religiosity or a non-religious outlook, may enter into their decision-making in end-of-life care," Dr. Seale concludes.
The study was supported by the National Council for Palliative Care. The author has disclosed no relevant financial relationships.
J Med Ethics. Published online August 26. 2010.

Headache in Teens Related to Lack of Exercise, Weight Gain, Smoking

August 19, 2010 — Teenagers who get little exercise, are overweight, or who smoke are more likely to have frequent headaches or migraines, report researchers.
"There was a significant trend for stronger associations between the number of negative lifestyle factors that were present and the different headache diagnoses and headache frequency," point out the investigators led by John-Anker Zwart, MD, from Oslo University in Norway. "We believe that the associations observed and the additive effect of these negative lifestyle factors on the prevalence of recurrent headache strongly indicates that these lifestyle factors are possible targets for headache preventive measures."
The new study appears in the August 18 issue of Neurology. As part of the cross-sectional study, researchers interviewed more than 5500 students about headache complaints. The adolescents also completed a questionnaire and underwent a clinical examination with height and weight measurements.
Investigators classified adolescents who were very physically fit and who were not current smokers as having a good lifestyle. Negative lifestyle factors were surprisingly common with low physical activity in 31%, smoking in 19%, and overweight in 16% of these teens.
In adjusted multivariate analyses, recurrent headache was associated with overweight (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.2 – 1.6; P < .0001), low physical activity (OR, 1.2; 95% CI, 1.1 – 1.4; P = .002), and smoking (OR, 1.5; 95% CI, 1.3 – 1.7; P < .0001). The presence of more than 1 negative lifestyle factor heightened the risk of headache.
Table 1. Prevalence Odds Ratios for Headache Diagnoses

Lifestyle	Total (n = 5588)	Recurrent (n = 1601)	Migraine (n = 392)	Tension Type (n = 950)	Nonclassifiable (n = 259)
Good	2856	1.0	1.0	1.0	1.0
Intermediate	1920	1.3	1.5	1.2	1.3
Poor	717	1.8	2.1	1.6	1.8
Very poor	95	3.4	3.7	2.8	5.0
P value	–	<.0001	<.0001	<.0001	<.0001

Table 2. Headache Frequency in Relation to Lifestyle

Lifestyle	Total (n = 5529)	Less Than Monthly (n = 306)	Monthly (n = 790)	Weekly or Daily (n = 446)
Good	2827	1.0	1.0	1.0
Intermediate	1897	1.0	1.3	1.3
Poor	712	1.4	1.9	2.0
Very poor	93	1.2	3.7	5.0
P value	–	.103	<.0001	<.0001

This study shows overweight, low physical activity, and smoking are independently and in combination associated with recurrent headache among adolescents, report the study authors.
In an accompanying editorial, Dr. Andrew Hershey and Dr. Richard Lipton say that "this study is a vital step toward a better understanding of lifestyle effects and the potential for behavioral interventions for adolescents with headache disorders."
Dr. Hershey is at the University of Cincinnati in Ohio and Dr. Lipton is at the Albert Einstein College of Medicine in the Bronx, New York. They point out the effects of each negative lifestyle factor were similar in magnitude for each headache type. "This lack of specificity for headache type raises the possibility that these factors may be associated not just with headache but with all-cause pain."
These results mirror those of another study published in June in the journal Headache. Investigators led by Rudiger von Kries, MD, from Ludwig-Maximilians-University in Munich, Germany, found that being physically active and abstaining from alcohol, caffeine, and tobacco could help prevent headaches in adolescents.
The study included 1260 students, and after controlling for socioeconomic variables, the prevalence of any headache was increased in teens who reported regularly drinking cocktails (OR, 2.0; 95% CI, 1.3 – 3.0), who drank at least 1 cup of coffee per day (OR, 2.0; 95% CI, 1.2 – 3.5), and who were physically less active (OR, 2.0; 95% CI, 1.3 – 3.1). Smoking daily had an OR of 1.8.
These findings, say editorialists, suggest that a better understanding of modifiable risk factors and trigger factors may lead to novel intervention strategies.
Study coauthor Dr. Stovner has received financial support from BTG, Minster Pharmaceuticals, Pfizer, GlaxoSmithKline, Merck, AstraZeneca, Allergan, Nycomed, Desitin Pharmaceuticals, GmbH, and EMD Serono. Dr. Stovner has also served as an expert legal witness for Oslo Tingrett. Dr. Holmen receives research support from the Norwegian Research Council.
Neurology. 2010;75:712-717.

H1N1 Influenza Pandemic Is Over, WHO Declares

August 10, 2010 — The controversial H1N1 influenza pandemic is officially over, the World Health Organization (WHO) declared today.
"We are now moving into the postpandemic period," said WHO Director-General Margaret Chan, MD. "The new H1N1 virus has largely run its course."
The 2009 H1N1 influenza virus has not disappeared, Dr. Chan noted, and it still poses a risk for serious illness, especially for young children, pregnant women, and persons with respiratory or chronic illnesses. However, the agency expects the virus to circulate and behave as one of several seasonal varieties in years to come, and not to dominate the pack.
"Many countries are reporting a mix of influenza viruses, again as is typically seen during seasonal epidemics," said Dr. Chan.
On June 11, 2009, WHO declared that transmission of the novel influenza virus had morphed into a full-blown pandemic, which is level 6 on a scale that the agency uses to classify influenza outbreaks. The postpandemic phase, which is at the end of the scale, indicates that influenza activity is at seasonal levels.
Earlier today, an emergency committee that advises Dr. Chan on the pandemic convened by teleconference and concluded that "the world was no longer experiencing an influenza pandemic, but that some countries continue to experience significant H1N1 (2009) epidemics," according to WHO.
During the spring and summer, virus transmission has dramatically tapered off in the Northern Hemisphere. WHO said on Tuesday that it had delayed making a decision on whether the pandemic was over until the emergency committee could assess the virus' behavior in the southern hemisphere during its winter influenza season. The committee concluded that for both hemispheres, 2009 H1N1 virus activity "no longer represented an extraordinary event requiring immediate emergency actions on an international scale."
Pandemic Less Deadly Than Feared Because of Hard Work, Good Luck
WHO has been accused in some quarters of declaring a "fake" pandemic, given that the H1N1 virus has killed fewer people than seasonal flu viruses on an annual basis in countries such as the United States. The agency has denied intentionally exaggerating the pandemic's severity for ulterior motives, such as boosting sales for vaccine manufacturers. Nevertheless, Dr. Chan said today that the pandemic "has turned out to be much more fortunate than what we feared a little over a year ago."
Dr. Chan attributed the fortunate outcome in the pandemic saga to a combination of hard work and "pure good luck."
"The virus did not mutate during the pandemic to a more lethal form," she said. "Widespread resistance to oseltamivir [Tamiflu; Roche Inc] did not develop. The vaccine proved to be a good match with circulating viruses and showed an excellent safety profile."
On another positive note, Dr. Chan said that infection rates of 20% to 40% in some areas have created a level of protective immunity, augmented by good vaccination coverage in many countries.
However, public health authorities should continue to remain vigilant about the 2009 H1N1 virus instead of letting down their guard, she said. For one thing, a small proportion of pandemic influenza patients — including young, healthy ones — experienced a severe form of primary viral pneumonia that was very hard to treat. Dr. Chan said nobody knows whether this pattern will continue during the postpandemic phase.
In addition, WHO expects the virus to change as a result of antigenic drift, lowering the protection offered by the community-wide immunity that has developed so far. At the same time, significant influenza outbreaks could occur in areas that got off lightly during the pandemic.
The WHO prescription for the postpandemic era mirrors its advice during the pandemic itself:

• Clinicians should vaccinate individuals against the 2009 H1N1 virus with either a monovalent vaccine or a trivalent seasonal vaccine that contains a strain of the pandemic virus (the United States will use the latter this fall).
• Good personal hygiene is still in order — clinicians should advise their patients to continue to cover their mouths when they sneeze or cough and to diligently wash their hands.
• As during the pandemic, patients who have a severe or deteriorating case of influenza should be treated with oseltamivir immediately, and clinicians should prescribe either oseltamivir or zanamivir (Relenza; GlaxoSmithKline) as soon as possible for patients who are higher risk for severe or complicated influenza.

ACIP Updates Guidelines for Prevention and Control of Influenza With Vaccines

August 3, 2010 — The US Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) has issued new 2010 recommendations for prevention and control of influenza with vaccines, according to guidelines reported early release in the July 29 issue of Morbidity and Mortality Weekly Report. This report updates the 2009 ACIP recommendations concerning the use of influenza vaccine for influenza prevention and control.
The report also describes a US Food and Drug Administration labeling change for Afluria (CSL Biotherapies) influenza virus vaccine to reflect the risk for fever and febrile seizure.
"Influenza A subtypes that are generated by a major genetic reassortment (i.e., antigenic shift) or that are substantially different from viruses that have caused infections over the previous several decades have the potential to cause a pandemic," write Anthony E. Fiore, MD, from the Influenza Division, National Center for Immunization and Respiratory Diseases, CDC, Atlanta, Georgia, and colleagues.
"In April 2009, a novel influenza A (H1N1) virus, 2009 influenza A (H1N1), that is similar to but genetically and antigenically distinct from influenza A (H1N1) viruses previously identified in swine, was determined to be the cause of respiratory illnesses that spread across North America and were identified in many areas of the world by May 2009. Influenza morbidity caused by 2009 pandemic influenza A (H1N1) remained above seasonal baselines throughout spring and summer 2009 and was the cause of the first pandemic since 1968."
Highlights of 2010 Guidelines
The 2010 guidelines emphasize the following:

• All persons at least 6 months old should receive annual vaccination for the 2010-2011 influenza season;
• During the 2010-2011 season, 2 doses of a 2010-2011 seasonal influenza vaccine should be given at a minimal interval of 4 weeks to children aged 6 months to 8 years with unknown vaccination status who have never received seasonal influenza vaccine before (or who received seasonal vaccine for the first time in 2009-2010 but received only 1 dose in their first year of vaccination), as well as to children who did not receive at least 1 dose of an influenza A (H1N1) 2009 monovalent vaccine regardless of previous influenza vaccine history;
• Vaccines should contain the 2010-2011 trivalent vaccine virus strains A/California/7/2009 (H1N1)-like (the same strain as was used for 2009 H1N1 monovalent vaccines), A/Perth/16/2009 (H3N2)-like, and B/Brisbane/60/2008-like antigens;
• The report describes Fluzone High-Dose (sanofi pasteur), a newly approved vaccine for persons at least 65 years old; and
• The report also provides information about other newly approved, standard-dose influenza vaccines and expanded age indications for previously approved vaccines.

The updated guidelines recommend starting vaccination efforts as soon as the 2010-2011 seasonal influenza vaccine is available and continuing throughout the influenza season, and they also provide a summary of safety data for US-licensed influenza vaccines. During the 2010-2011 influenza season, vaccination and healthcare providers should check CDC's influenza Web site for any updates or supplements that might be needed to these recommendations, as well as for recommendations for influenza diagnosis and antiviral use published before the start of the 2010-2011 influenza season.
Recommendations for 2010
A summary of recommendations for influenza vaccination for 2010 is as follows:

• Annual vaccination is recommended for all persons aged 6 months or older.
• As providers and programs make the transition to routine vaccination of all persons aged 6 months or older, a focus of vaccination efforts should continue to be protection of persons at higher risk for influenza-related complications.
• When vaccine supply is limited, vaccination efforts should prioritize persons who:   
  • Are aged 6 to 59 months or at least 50 years;
  • Have chronic pulmonary (including asthma), cardiovascular (except hypertension), renal, hepatic, neurologic, hematologic, or metabolic disorders (including diabetes mellitus);
  • Have disorders of immunosuppression, including those caused by medications or by HIV);
  • Are or will be pregnant during the influenza season;
  • Might be at risk for Reye's syndrome after influenza virus infection because they are aged 6 months to 18 years and are receiving long-term aspirin therapy;
  • Are residents of nursing homes and other long-term care facilities; American Indians/Alaska Natives; morbidly obese (body mass index ≥ 40 kg/m²); and/or healthcare personnel;
  • Are household contacts and caregivers of persons with medical conditions putting them at greater risk for severe complications from influenza, or of children younger than 5 years and adults 50 years or older. The guidelines particularly emphasize vaccinating contacts of children younger than 6 months.

"Emphasis on providing routine vaccination annually to certain groups at higher risk for influenza infection or complications is advised, including all children aged 6 months–18 years, all persons aged ≥50 years, and other persons at risk for medical complications from influenza," the authors of the report write. "Despite a recommendation for vaccination for approximately 85% of the U.S. population over the past two seasons, <50% of the U.S. population received a seasonal influenza vaccination in 2008–09 or 2009–10. Estimated vaccine coverage for the 2009 H1N1 monovalent vaccine coverage was <40%."
MMWR Morb Mortal Wkly Rep. July 29, 2010;59(Early Release);1-62.