August 5, 2009 (American Roentgen Ray Society) - Noninvasive imaging (MRI) may aid physicians in the early diagnosis, staging and treatment of diabetes, according to a study performed at Massachusetts General Hospital and Harvard Medical School in Boston, MA. This is the first study of its kind to apply noninvasive imaging techniques to diabetes research."With noninvasive MRI we have the ability to evaluate beta cell mass, a major factor of insulin secretion that is significantly reduced in type two diabetes and almost gone in type one," said Anna Moore, MD, lead author of the study. "We are also able to detect inflammation of the pancreas and vascular changes associated with type one and type two diabetes. This opens a huge area that is closed right now," said Dr. Moore.

"Knowing the number of functional beta cells left would allow physicians to develop the most appropriate treatment plans for their patients. It would also allow them to respond, change or manipulate those treatment plans at any time," she said.

"Noninvasive MRI could no doubt tremendously assist in achieving insulin independence in patients with diabetes," said Dr. Moore.

This study appears in the August issue of the American Journal of Roentgenology.

August 4, 2009 (Newswise) - Feelings of depression could be one reason patients fail to follow their doctors' orders on exercising and eventually become less physically active, a new research review finds.Although past research shows that exercise improves chronic health conditions, such as heart disease and diabetes, it also shows that patients with these conditions often suffer from depression.

The new analysis evaluated 11 studies comprising some 20,000 patients. Eight studies reported that having symptoms of depression after a coronary event, such as heart attack, was a significant risk factor for developing a sedentary lifestyle or a poor adherence to an exercise regimen recommended by the patients' doctor.

The review appears in the July/August issue of the journal General Hospital Psychiatry.

One study, for example, investigated the role of depression and anxiety in 224 heart attack survivors, at three months and 12 months after their hospitalization. Of those with anxiety and depression during hospitalization, 59 percent had a significant decrease in exercise after three months, compared with 31 percent of those who were not depressed. A year later the gap widened, with 51 percent of depressed patients exercising less compared with 26 percent of non-depressed patients.

The studies used different methods to measure depression and physical activity and there was a great difference in how they compared factors such as the patients' health, physical activity and depression.

There are many suggested theories to explain why depression leads to a decline in activity. Babak Roshanaei-Moghaddam, M.D. of the department of psychiatry and behavioral sciences at University of Washington in Seattle and lead author of the study offered one theory.

"We have hypothesized that there are both behavioral habits associated with depression, such as smoking and obesity, which may then limit exercise motivation and enjoyment, as well as biologic factors that can cause obesity and decrease energy level, exercise tolerance and pain threshold," he said.

Evette Joy Ludman, Ph.D., of Seattle-based Group Health Cooperative, who had no affiliation with the study, agreed.

"Depression can indeed make people have less motivation and energy to exercise," Ludman said. "The sad part about this is that physical activity is not only important for preventing and managing many chronic conditions; it can be very helpful for improving mood and other symptoms of depression."

June 25, 2009 (EurekAlert) - Doctors have known for decades that foods like white bread and corn flakes aren't good for cardiac health. In a landmark study, new research from Tel Aviv University now shows exactly how these high carb foods increase the risk for heart problems."Looking inside" the arteries of students eating a variety of foods, Dr. Michael Shechter of Tel Aviv University's Sackler School of Medicine and the Heart Institute of Sheba Medical Center -- with collaboration of the Endocrinology Institute -- visualized exactly what happens inside the body when the wrong foods for a healthy heart are eaten. He found that foods with a high glycemic index distended brachial arteries for several hours.

Elasticity of arteries anywhere in the body can be a measure of heart health. But when aggravated over time, a sudden expansion of the artery wall can cause a number of negative health effects, including reduced elasticity, which can cause heart disease or sudden death.

Using a clinical and research technique pioneered by his laboratory in Israel, Dr. Shechter was able to visualize what happens inside our arteries before, during and after eating high carb foods. It is a first in medical history. The results were published in the Journal of the American College of Cardiology.

Time to skip the wedding cake?

"It's very hard to predict heart disease," says Dr. Shechter, a fellow of the American College of Cardiology and the American Heart Association. "But doctors know that high glycemic foods rapidly increase blood sugar. Those who binge on these foods have a greater chance of sudden death from heart attack. Our research connects the dots, showing the link between diet and what's happening in real time in the arteries."

Like the uncomfortable medical warnings on packets of cigarettes, this new research could lead to a whole new way to show patients the effects of a poor diet on our body.

Using 56 healthy volunteers, the researchers looked at four groups. One group ate a cornflake mush mixed with milk, a second a pure sugar mixture, the third bran flakes, while the last group was given a placebo (water). Over four weeks, Dr. Shechter applied his method of "brachial reactive testing" to each group. The test uses a cuff on the arm, like those used to measure blood pressure, which can visualize arterial function in real time.

The results were dramatic. Before any of the patients ate, arterial function was essentially the same. After eating, except for the placebo group, all had reduced functioning.

All roads lead to the endothelium

Enormous peaks indicating arterial stress were found in the high glycemic index groups: the cornflakes and sugar group. "We knew high glycemic foods were bad for the heart. Now we have a mechanism that shows how," says Dr. Shechter. "Foods like cornflakes, white bread, french fries, and sweetened soda all put undue stress on our arteries. We've explained for the first time how high glycemic carbs can affect the progression of heart disease." During the consumption of foods high in sugar, there appears to be a temporary and sudden dysfunction in the endothelial walls of the arteries.

Endothelial health can be traced back to almost every disorder and disease in the body. It is "the riskiest of the risk factors," says Dr. Shechter, who practices at the Chaim Sheba Medical Center ― Tel Hashomer Hospital. There he offers a treatment that can show patients ― in real time ― if they have a high risk for heart attacks. "Medical tourists" from America regularly visit to take the heart test.

The take-away message? Dr. Shechter says to stick to foods like oatmeal, fruits and vegetables, legumes and nuts, which have a low glycemic index. Exercising every day for at least 30 minutes, he adds, is an extra heart-smart action to take.

June 25, 2009 (EurekAlert) - A test commonly used to help identify women with diabetes during pregnancy may be an accurate, convenient and inexpensive way to screen the general population for unrecognized diabetes and prediabetes, according to Emory University researchers.A test commonly used to help identify women with diabetes during pregnancy may be an accurate, convenient and inexpensive way to screen the general population for unrecognized diabetes and prediabetes, according to Emory University researchers.

The results of the study, "Glucose challenge test screening for prediabetes and undiagnosed diabetes" will be published online and in print in the journal Diabetologia.

"Widespread use of the glucose challenge test (GCT) to screen Americans for prediabetes and diabetes could provide a major opportunity to improve the health of more than 40 million people," said lead study author Lawrence S. Phillips, MD, Emory University School of Medicine Professor of Medicine, Division of Endocrinology.

The study screened 1,573 volunteer participants who had never been diagnosed with diabetes. At a first visit, at different times of the day and without restriction of meals, participants were given a 50-gram glucose drink. Glucose was measured both before the drink (random glucose) and an hour after the drink (GCT glucose).

At a follow-up visit held in the morning after an overnight fast, participants had measurement of hemoglobin A1c (a standard test used to monitor diabetes), and a 75-gram oral glucose tolerance test (OGTT). The OGTT is the "gold standard" for diagnosing diabetes and prediabetes.

After screening, researchers found that 4.6 percent of the participants had previously unrecognized diabetes, and 18.7 percent had prediabetes.

The GCT was the most accurate screening test for these problems, significantly better than the random glucose or A1c tests. Since the good performance of the GCT was unaffected by the time of day, or times after meals, the GCT could be performed during a routine office visit. If a patient's GCT glucose level is low, he/she wouldn't need to be screened again for another two or three years, but if the GCT glucose level is high, patients would need a confirmatory oral glucose tolerance test.

This approach is similar to screening women for diabetes during pregnancy. GCT screening is almost universal for women in their sixth month of pregnancy.

The GCT provided consistent results for a diverse group of patients - old and young, normal weight and overweight, men and women, with and without a family history of diabetes, etc. The GCT also appeared to be less expensive than other screening strategies.

Early diagnosis is a benefit both for people who have diabetes or prediabetes, and for their health care teams. Regular glucose challenge test screening (GCT first, then a follow-up OGTT if the GCT glucose is high) would be a way to assure early diagnosis, according to Phillips and team.

"Glucose challenge test screening could help improve disease management by permitting early initiation of therapy aimed at preventing or delaying the development of diabetes and its complications," says Phillips.

Diabetes is a disease in which the body does not produce or properly use insulin. Insulin is a hormone that is needed to convert sugar, starches and other food into energy needed for daily life.

According to the American Diabetes Association, 23.6 million U.S. children and adults, or 7.8 percent of the population, have diabetes. While an estimated 17.9 million have been diagnosed with diabetes, 5.7 million people are unaware that they have the disease.

Pre-diabetes is a condition that occurs when a person's blood glucose levels are higher than normal but not high enough for a diagnosis of type 2 diabetes. There are 57 million Americans who have pre-diabetes, in addition to the 23.6 million with diabetes.

June 23, 2009 (EurekAlert) - Underweight people and those who are extremely obese die earlier than people of normal weight-but those who are overweight actually live longer than people of normal weight. Those are the findings of a new study published online in Obesity by researchers at Statistics Canada, Kaiser Permanente Center for Health Research, Portland State University, Oregon Health & Science University, and McGill University.
"It's not surprising that extreme underweight and extreme obesity increase the risk of dying, but it is surprising that carrying a little extra weight may give people a longevity advantage," said David Feeny, PhD, coauthor of the study and senior investigator for the Kaiser Permanente Center for Health Research.

"It may be that a few extra pounds actually protect older people as their health declines, but that doesn't mean that people in the normal weight range should try to put on a few pounds," said Mark Kaplan, DrPH, coauthor and Professor of Community Health at Portland State University. "Our study only looked at mortality, not at quality of life, and there are many negative health consequences associated with obesity, including high blood pressure, high cholesterol, and diabetes."

"Good health is more than a BMI or a number on a scale. We know that people who choose a healthy lifestyle enjoy better health: good food choices, being physically active everyday, managing stress, and keeping blood pressure, cholesterol, and blood sugar levels in check," said Keith Bachman MD, a weight management specialist with Kaiser Permanente's Care Management Institute.

The study examined the relationship between body mass index and death among 11,326 adults in Canada over a 12-year period. (BMI uses height and weight to estimate body fat.) Researchers found that underweight people had the highest risk of dying, and the extremely obese had the second highest risk. Overweight people had a lower risk of dying than those of normal weight.

This is the first large Canadian study to show that people who are overweight may actually live longer than those of normal weight. An earlier study, conducted in the United States and published in 2005 in the Journal of the American Medical Association, showed similar results.

For this study, researchers used data from the National Population Health Survey conducted by Statistics Canada every two years. During the study period, from 1994/1995 through 2006/2007, underweight people were 70 percent more likely than people of normal weight to die, and extremely obese people were 36 percent more likely to die. But overweight individuals were 17 percent less likely to die. The relative risk for obese people was nearly the same as for people of normal weight. The authors controlled for factors such as age, sex, physical activity, and smoking.

June 22, 2009 (EurekAlert) - New research shows that physicians failed to report clinically significant abnormal test results to patients -- or to document that they had informed them -- in one out of every 14 cases of abnormal results. In some medical groups, the failure rate is close to zero; in others it is as high as one in four abnormal results.The analysis of 5,434 patient records from 23 physician practices across the country was led by Dr. Lawrence P. Casalino, chief of the Division of Outcomes and Effectiveness Research in the Department of Public Health of Weill Cornell Medical College, and published today in the Archives of Internal Medicine.

Dr. Casalino and his co-investigators revealed that groups using simple processes to manage test results had lower failures rates. Groups that did not consistently use these processes had both higher failure rates and physicians who were dissatisfied with their group's processes for managing test results. The study also found that having an electronic medical record did not reduce failure-to-inform rates -- and even increased them -- if the practice did not have good processes in place for managing test results.

"Failure to report abnormal test results can lead to serious, even lethal consequences for the patient," says Dr. Casalino. "The good news is that physicians who use a simple set of systematic processes to deal with test results can greatly lessen their error rates."

The study suggests that five simple, common-sense processes are useful for dealing with test results: (1) all test results are routed to the responsible physician; (2) the physician signs off on all results; (3) the practice informs patients of all results, normal and abnormal, at least in general terms; (4) the practice documents that the patient has been informed; and (5) patients are told to call after a certain time interval if they have not been notified.

"We found that very few physician practices had explicit rules for managing test results," says Dr. Casalino, who is also associate professor of public health at Weill Cornell Medical College. "In many practices, each physician devised his or her own method. And in many cases, physicians and their staff told patients that 'no news is good news' -- meaning they should assume that their tests are normal unless they are contacted. This is a dangerous assumption."

"With the recent enactment of federal stimulus legislation to support greater adoption of health information technology, this study demonstrates why health IT hardware alone will not improve care," says Dr. Mark Smith, president & CEO of the California HealthCare Foundation, which funded the research. "Ensuring that processes are in place to efficiently notify patients of their lab results should be part of the meaningful use of electronic health records."

"Dr. Casalino's research provides concrete and immediately useful steps that can and should be put into place to improve the delivery of medical care," says Dr. Alvin I. Mushlin, Professor and Chairman of the Department of Public Health at Weill Cornell Medical College. "With good processes, we can ensure that patients with abnormal lab results get proper follow-up."

June 9, 2009 (EurekAlert) - According to a research abstract that will be presented on Tuesday, June 9, at SLEEP 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies, adolescent obesity is associated with having less sleep. Reduction in sleep could be related to a higher caffeine intake, more hours of technology use and increased symptoms of sleep disorders (such as snoring).Results indicate that children who slept less consumed more caffeine and had more hours of screen time (use of television, Internet, computer and video games). A higher body mass index (BMI) was also associated with shorter sleep duration. More hours of screen time were also associated with higher caffeine consumption.

According to lead author Amy Drescher, PhD, research specialist at the University of Arizona in Tucson, there are many reasons that kids gain weight, and inadequate sleep is just one of them.

"Boys had significantly more vigorous exercise, recreational activity than girls," said Drescher. "The sleep and obesity connection is not always seen because factors such as exercise may keep weight in check."

The study gathered data from 320 children who completed detailed dietary and physical activity questionnaires. Correlation and regression analysis were used to study the relationships among diet, physical activity and self-reported sleep duration and screen time. Mean age of the sample group was 13.3 years; 51.8 percent of participants were male, 65 percent were Caucasian and 35 percent were Hispanic.

Inadequate sleep combined with increased electronic screen time and caffeine intake may have negative implications for adolescents' health, psychosocial well-being and academic performance.

June 9, 2009 (EurekAlert) - Individuals with insomnia and objective short sleep duration are at increased risk for developing diabetes, according to a research abstract that will be presented on Tuesday, June 9, at SLEEP 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies.Results indicate that compared with people who slept six hours or more while being monitored in the sleep laboratory, individuals with insomnia who slept for five or fewer hours had the highest risk of diabetes (odds ratio of 2.95); people with insomnia who slept for five to six hours also had an elevated risk of diabetes (odds ratio of 2.07).

The study gathered data from 1,741 men and women who were randomly selected from Central Pennsylvania; participants were studied in a sleep laboratory. Diabetes was defined based on either fasting blood sugar or treatment. Insomnia was defined by a complaint of insomnia with a duration of at least one year, while "poor sleep" was defined as a complaint of difficulty falling asleep, staying asleep or early final awakening. Polysomnographic sleep duration was classified into three categories: people who slept for six or more hours, those who slept five to six hours and those who slept for five hours or less. Logistic regression was used to calculate odds ratios for diabetes.

According to lead author Alexandros Vgontzas, MD, endowed chair in Sleep Disorders Medicine at Penn State College of Medicine in Hershey, Pa., patients suffering from insomnia with short sleep duration are at a serious health risk.

"The more severe form of insomnia (insomnia with short objective sleep duration) is associated with a risk for diabetes that is similar to the elevated risk associated with obstructive sleep apnea," said Vgontzas.

Other studies also have found serious medical risks associated with insomnia and objective short sleep duration; another study led by Vgontzas that will be presented at SLEEP 2009 found that insomnia with objective short sleep duration is also associated with increased risk of mortality in men.

According to the study's authors, findings indicate that people with insomnia should seek evaluation and treatment from their medical provider. Although the results suggest that people with insomnia have a lower risk for physical problems if their sleep duration is normal, they still are at risk for depression and may suffer from the behavioral effects of insomnia.

June 8, 2009 (EurekAlert) - According to a research abstract that will be presented on Monday, June 8, at SLEEP 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies, both long and short sleepers are at greater risk for diabetes. Individuals sleeping for more than eight hours per night may be particularly vulnerable.Results indicate that the adjusted odds ratio was 1.24 for diabetes associated with short sleep (five hours per night or less) and 1.48 for diabetes associated with long sleep (nine or more hours per night). The prevalence of diabetes was 12 percent for blacks and 8 percent for whites, and the prevalence of obesity (body mass index of 30 kg/m2 or greater) was 52 percent for blacks and 38 percent for whites.

According to lead author Girardin Jean-Louis, PhD, associate professor at the SUNY Downstate Medical Center at the Brooklyn Health Disparities Research Center in New York, findings suggest that both patients who have excessive or insufficient sleep time have increased risk for developing diabetes, a serious health condition.

"Both blacks and whites who were obese tended to have short sleep time. These findings suggest that race significantly influenced the risk of obesity conferred by short sleep duration," said Jean-Louis. "As obesity is associated with diabetes and sleep apnea, it may be that more blacks are at risk for sleep apnea and diabetes, which are both linked to cardiovascular disease."

The study involved data from 29,818 individuals who completed the 2005 National Health Interview Survey, a cross-sectional household interview survey using multistage area probability and design. Data were collected from all 50 states and Washington, D.C. Participants were between the ages of 18 and 85 years; 85 percent of the sample was white and 15 percent was black; 56 percent of participants were women.

The authors conclude that more research is needed to identify the factors that could explain the relationship between long sleep duration and diabetes.

June 7, 2009 (EurekAlert) - Optimal medical therapy for patients with diabetes and stable coronary heart disease is equally effective at lowering the risk of death, heart attack, and stroke as prompt revascularization procedures with either coronary bypass surgery or angioplasty, according to results from an international multicenter clinical trial supported by the National Institutes of Health. Optimal medical therapy includes intensive drug therapy and lifestyle interventions, such as dietary changes and smoking cessation.The Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) simultaneously compared two cardiovascular treatment approaches and two diabetes control strategies to improve survival and to lower the risk of heart attacks and strokes. The findings are published online by the New England Journal of Medicine today, in conjunction with the researchers' presentation at the American Diabetes Association's 69th Annual Scientific Sessions in New Orleans, La.

BARI 2D also found - and is the first study to suggest -- that patients who had prompt bypass surgery in addition to optimal medical therapy had significantly fewer non-fatal heart attacks or strokes compared to similar patients who initially received optimal medical therapy alone. No such benefit was seen in patients who received prompt angioplasty, most of whom also received stent placement (a wire mesh scaffold to keep the affected artery open), versus similar patients who initially received optimal medical therapy alone. However, participants in the bypass surgery group were more likely to have more extensive coronary artery disease (CAD) than those in the angioplasty group; more research is needed to confirm these findings. Both angioplasty and bypass surgery are revascularization procedures to relieve or bypass blockages in the coronary arteries.

Researchers also discovered that, overall, strategies using drugs that aim to make insulin work better by lowering the body's resistance to insulin (called insulin sensitization) are as effective as a strategy emphasizing drugs that provide insulin or that stimulate insulin production (insulin provision drugs).

"By comparing different strategies for both blood sugar control and prevention of cardiovascular events such as heart attack and stroke, we aim to provide physicians with evidence-based guidance to help them identify the safest and most effective therapies for their patients," said Elizabeth G. Nabel, M.D., director of the National Heart, Lung, and Blood Institute (NHLBI), the primary funder of the study.

Adults with type 2 diabetes are two to four times more likely to develop heart disease. In addition, heart attacks and stroke often occur earlier than in people without diabetes - and are more likely to be fatal. Sixty-five percent of people with diabetes die from cardiovascular disease.

BARI 2D was conducted in 49 clinical sites in the United States, Canada, Brazil, Mexico, the Czech Republic, and Austria. The study was coordinated by the Epidemiology Data Center at the University of Pittsburgh Graduate School of Public Health. Participants were 2,368 adults (average age 62 years) with established type 2 diabetes (average duration of 10 years) and stable CAD. One component of the study compared optimal drug treatment to control blood sugar levels, cholesterol, and blood pressure with prompt (within four weeks of the start of the study) coronary revascularization by either bypass surgery or angioplasty to optimal drug treatment alone. In angioplasty, blocked arteries are opened by inflating a small balloon inside a narrow vessel and often followed by the placement of a stent. Of the 798 BARI 2D participants selected to receive prompt angioplasty, 91 percent had a stent inserted, of whom about one-third received a drug-eluting stent.

At enrollment, all participants' CAD had to be stable enough so that the patients could be safely managed with optimal medical therapy without immediate revascularization. Participants were selected to be in either the bypass or the angioplasty group based on whether (in the judgment of their physician), the extent and severity of blockages in their coronary arteries would be best treated by coronary bypass surgery or angioplasty. As reflective of standard medical practice, patients with more extensive and severe CAD were more likely to be candidates for bypass surgery than angioplasty. When they were screened to enter the trial, approximately two-thirds of BARI 2D participants were considered suitable candidates for elective angioplasty, while the remaining one-third were considered candidates for elective bypass surgery.

Within the bypass surgery and angioplasty groups, participants were randomly assigned to either promptly receive the designated revascularization procedure or to receive optimal medical therapy alone. Thus, the two coronary revascularization procedures were not compared to each other; rather, patients receiving either revascularization procedure were independently compared to their own control groups receiving optimal medical therapy alone.

Participants randomized to promptly receive revascularization underwent the designated procedure within four weeks from the start of the study while also receiving optimal medical therapy. Participants in the medical therapy alone group could undergo revascularization during the study if needed; about 40 percent of participants in the medical therapy groups did so.

Overall, researchers found that after an average follow up of five years, there were no differences in mortality rates, the primary endpoint of the study, which was about 12 percent in both groups. In addition, deaths combined with nonfatal cardiovascular events - a principal secondary outcome - between the combined revascularization groups who received early coronary procedures compared to those in the medical therapy alone groups were similar (23 percent versus 24 percent, respectively). However, among the subgroup of participants who were pre-identified as candidates for coronary bypass surgery, there were significantly fewer subsequent major cardiovascular events (death or nonfatal heart attacks or strokes) among those who had bypass surgery within the first month of being in the study compared to those who initially received optimal medical therapy alone (22 percent versus 30 percent, respectively).

In the diabetes control component of the study, researchers randomly divided the same participants into two blood sugar control strategy groups. One strategy emphasized insulin-sensitizing drugs, such as biguanides (metformin) and thiazolidinediones (primarily rosiglitazone), which lower the body's resistance to insulin. The other strategy group emphasized insulin-providing drugs - insulin treatment or drugs that stimulate the body to make more insulin, including sulfonylurea drugs (such as glipizide) and meglitinides (such as replaginide). These two drug strategies address two different problems in type 2 diabetes.

Participants in both groups were treated to targeted levels of glycated hemoglobin (HbA1c) levels of less than 7.0 percent, which is consistent with current diabetes care guidelines. HbA1c is a measure of blood sugar control over a period of several months. On average, participants in the insulin sensitizing group had an HbA1c level of 7.0 percent, and participants in the insulin providing group had an HbA1c level of 7.5 percent.

"Other studies have suggested that insulin resistance contributes directly to the development of coronary artery disease," noted Suzanne Goldberg, R.N., M.S.N., NHLBI project officer of the study and program director in the Atherothrombosis and Coronary and Artery Disease Branch in the Division of Cardiovascular Diseases. "Our study was an opportunity to directly compare the effects of drugs that enhance the body's ability to use insulin to the more traditional drugs that increase the amount of insulin."

Overall, the numbers of deaths and cardiovascular events were about the same in both diabetes treatment strategy groups. In addition, because of safety concerns raised in other studies, BARI 2D researchers conducted an in-depth analysis of cardiovascular disease rates in patients receiving rosiglitazone (Avandia) versus other diabetes drugs, and found no evidence of increased risk of heart attacks in participants receiving rosiglitazone.

"We found some indications that insulin-sensitizing drugs might be beneficial for certain patients with diabetes, especially those with more extensive coronary artery disease who undergo bypass surgery, but more research is needed," noted Sheryl F. Kelsey, Ph.D., professor of epidemiology at the University of Pittsburgh Graduate School of Public Health, and a principal investigator and coauthor of the study.