Obesity And Knee Osteoarthritis Shorten Healthy Years Of Life

An estimated 10 million Americans suffer from knee osteoarthritis (OA), making it one of the most common causes of disability in the US. Due to obesity and symptomatic knee OA, Americans over the age of 50 will together lose the equivalent of 86 million healthy years of life, concluded researchers at Brigham and Women's Hospital (BWH), who investigated the potential gains in quality and quantity of life that could be achieved averting losses due to obesity and knee OA. These findings are published in theAnnals of Internal Medicine.

"Reducing obesity to levels observed in 2000 would prevent 172,792 cases of coronary heart disease, 710,942 cases of diabetes, and 269,934 total knee replacements," said Elena Losina, PhD lead author of the study and co-director of Orthopedics and Arthritis Center for Outcomes Research in the Dept of Orthopedic Surgery at BWH. "All told, it would save roughly 19.5 million years of life among US adults aged 50-84."

Experts have long known that knee osteoarthritis is on the rise among Americans, due in part to the growing obesity epidemic and longer life expectancy. Obesity and knee OA are among the most frequent chronic conditions in older Americans. However, how that translates into years of healthy life lost has not been accurately estimated. Dr. Losina and colleagues used a mathematical simulation model to assemble national data on the occurrence of knee OA, obesity and other important conditions such as coronary heart disease, diabetes, cancer and chronic lung disease. Their analysis examines the contribution of both obesity and knee OA to losses in quantity and quality of life. It also evaluates how those losses are distributed among racial and ethnic subpopulations in the United States.

"There are 86 million healthy years of life at stake, a disproportionate number of them being lost by Black and Hispanic women," said Jeffrey N. Katz, MD, Director of the Orthopedics and Arthritis Center for Outcomes Research at the BWH and a senior author of the study. "These staggering numbers may help patients and physicians to better grasp the scale of the problem and the potential benefits of behavior change."

This study was funded by grants from National Institute of Arthritis, Musculoskeletal and Skin Disease and the Arthritis Foundation. Contributing authors include Rochelle P. Walensky, MD, MPH, Massachusetts General Hospital, William M. Reichmann, MA, Holly L. Holt, Hanna Gerlovin, Daniel H. Solomon, MD, MPH and Jeffrey N. Katz, from Brigham and Women's Hospital, David Hunter MD from University of Sydney, Australia, Joanne M. Jordan, MD from University of North Carolina, Chapel Hill, Drs. Lisa Suter and A. David Paltiel, from Yale University School of Medicine.

FDA Approves Gastric Band For Obese Americans

Losing weight is extremely difficult for some. So difficult in fact, that a new stomach band has been approved by the FDA for those persons with a body mass index (BMI) of between 30 and 40, amounting to approximately 37 million Americans in fact that can now use this new product put out by Allergan Incorporated.

A frequent use of the BMI is to assess how much an individual's body weight departs from what is normal or desirable for a person of his or her height. The weight excess or deficiency may, in part, be accounted for by body fat (adipose tissue) although other factors such as muscularity also affect BMI significantly (see discussion below and overweight). The World Health Organization regards a BMI of less than 18.5 as underweight and may indicate malnutrition, an eating disorder, or other health problems, while a BMI greater than 25 is considered overweight and above 30 is considered obese. These ranges of BMI values are valid only as statistical categories when applied to adults, and do not predict health.

Frederick Beddingfield, M.D., Allergan's Vice President of Clinical Research and Development states:

"Given the proven and significant health ramifications of obesity, we are pleased with the FDA's decision to expand the use of the LAP-BAND System. Although this label expansion represents a significant advancement in obesity treatment, the LAP-BAND System is not intended for everyone. The LAP-BAND System does represent a potential treatment option for those patients with obesity and a related health condition, who have failed more conservative weight-loss therapies, such as diet and exercise and pharmacotherapy, and under consultation with their physician, have determined that weight-loss surgery is the next best treatment option."

Smoking is America's number one killer, but obesity is the second-leading cause of preventable death in the United States. Given its known correlation to life-threatening comorbid conditions, such as heart disease, stroke, Type 2 diabetes, high blood pressure, sleep apnea and even premature death, obesity is a disease that requires medical treatment. Medical research has found that, if left untreated, those individuals who are currently obese will likely remain obese.

Robert Michaelson, M.D., Ph.D., Northwest Surgical Weight Loss Surgery, Everett, Washington, and Clinical Trial Investigator continues:

"As a surgeon, I see patients every day who have been obese for years and have tried several diet and exercise programs without success. These patients frequently feel judged by their weight, as obesity is often viewed as a lack of will power, which it is not. Obesity is a disease, which requires medical treatment, but unfortunately diet and exercise alone do not work for everyone. The LAP-BAND System meets an unmet clinical need, as it provides an effective treatment option, which is used in combination with diet and exercise, to enable sustained weight loss."

The LAP-BAND System was originally approved by the FDA in 2001 for use in severely obese adults, individuals with a BMI of 35 with at least one severe comorbid condition or a BMI of 40, or those who are at least 100 pounds or more overweight. In addition, the LAP-BAND System has been approved internationally since 1993. The System is now the first and only FDA-approved device for bariatric surgery in patients with a BMI of 30-35.

Over the past 18 years, more than 650,000 procedures have been performed, leading to over two million patient years of exposure for the device.

 

Link Between Obesity, High-Fat Meals And Heart Disease Reinforced By Study

The effect of a high-fat meal on blood vessel walls can vary among individuals depending on factors such as their waist size and triglyceride levels, suggests new research at UC Davis.

The new research reinforces the link between belly fat, inflammation and thickening of the arterial linings that can lead to heart disease and strokes.

Triglycerides are types of fat molecules, commonly associated with "bad cholesterol," known to increase risk of inflammation of the endothelium, the layer of cells that lines arteries.

"The new study shows that eating a common fast food meal can affect inflammatory responses in the blood vessels," said Anthony Passerini, assistant professor of biomedical engineering at UC Davis, who led the project.

"Our techniques allowed us to measure the inflammatory potential of an individual's lipids outside of the body and to correlate that with easily measured characteristics that could be used to help better understand a person's risk for vascular disease," Passerini said.

Passerini collaborated with Scott Simon, professor of biomedical engineering at UC Davis, to develop cell culture models to mimic the properties of blood vessels. They wanted to learn how triglyceride levels can cause endothelial inflammation, and find a way to assess an individual's inflammatory potential.

They recruited 61 volunteers with high and normal fasting triglyceride levels and a range of waist sizes, then measured levels of triglyceride particles in their blood after they ate a typical fast food breakfast from a major fast food franchise: two breakfast sandwiches, hash browns and orange juice.

Passerini's team found that after eating the high-fat meal, the size of a type of a particle called triglyceride-rich lipoprotein (TGRL) varied directly with the individual's waist size and preexisting blood triglyceride level. These particles can bind to the endothelium, triggering inflammation and an immune response that brings white blood cells to repair the damage. Over time, this leads to atherosclerosis.

The researchers tested whether TGRL particles from the volunteers' blood could cause cultured endothelial cells in the laboratory to express markers for inflammation.

There was a mixed response: individuals with both a waist size over 32 inches (not terribly large by most standards) and high triglyceride levels had large lipoprotein particles that bound easily to the endothelial cells and caused inflammation in response to an immune chemical "trigger."

The TGRLs only caused inflammation when exposed to this immune molecule, which suggests that people with existing low-grade inflammation may be more susceptible to endothelial dysfunction related to triglyceride "spikes" that occur after eating high-fat meals, Passerini said.

In people who are predisposed, repeated episodes of inflammation could lead to atherosclerosis. Passerini's lab is continuing to investigate how abdominal obesity, high triglyceride levels and inflammation can lead to atherosclerosis.

New Mothers' Postpartum Lifestyle And Parenting Stress

Post-pregnancy excess weight is likely caused by the impact of new parenthood stress on physical activity, Georgia Health Sciences University researchers say.

In a study of 60 first-time mothers, researchers linked higher post-pregnancy body mass index - weight in relation to height - to a combination of a high BMI before pregnancy, excessive weight gain during pregnancy, parenting stress and a sedentary lifestyle, according to a study published in Women & Health.

The study gauged parental stress by asking participants to rate statements such as "I feel like I have less time to myself" and "I enjoy being a parent." They were also asked to recall their physical activity over the previous 24 hours, categorizing that activity from light to vigorous.

"Sedentary lifestyle, or a low amount of physical activity, was most influenced by the type of parenting stress the mothers reported," says Dr. Deborah Young-Hyman, behavioral psychologist with the Georgia Prevention Institute. "More parenting stress, especially depression, was associated with less physical activity and a higher postpartum BMI."

Interestingly, social interaction, generally considered a measure of well-being, correlated with a higher body mass index, she noted.

"We think women are socializing with their friends, not isolating themselves, but they are doing sedentary things like talking on the phone, watching television or hanging out at home, instead of taking their babies on a walk together."

New moms with a higher BMI did report more depressive symptoms, but overall felt competent as parents. Those with lower BMIs reported more physical activity (and less depressive symptoms) but more concern about their competence as parents.

"We know that physical activity improves your mood and helps you lose weight, but no one has ever asked how physical activity is related to parenting stress in first-time moms," Young-Hyman said. "The bottom line is that parenting stress does impact the postpartum lifestyles of new moms," she said.

Based on a current study tracking how first-time mothers adjust to parenthood, researchers will develop an intervention to help new moms create healthy lifestyles for both themselves and their babies ?" preventing overweight mothers and children.

Study Finds Children In Public Housing Play Outdoors More, May Impact Obesity Prevention

Young children living in urban public housing spend more time playing outdoors than other urban children, according to researchers at Rice University, Columbia University and Princeton University.

Contrary to the expectations of the researchers, who hypothesized that children living in poorer circumstances would be playing outside less, the study found that 5-year-olds living in public housing played outside 13 percent more per day, on average, than did other urban 5-year-olds. Children living in places of high physical disorder - areas with visible graffiti, trash, and abandoned homes - also played outside more per day.

The researchers also concluded that the ratio of outdoor play to television watching is a significant predictor of body mass indexes (BMIs). The study, "Young Children in Urban Areas: Links Among Neighborhood Characteristics, Weight Status, Outdoor Play and Television-Watching," showed that for each additional hour the children played outside over the amount of time spent watching television, children scored 1.5 percentile points lower on BMI. BMI is a measure of body fat based on height and weight. The higher a person's BMI, the higher their risk for heart disease, high blood pressure, type 2 diabetes and other health problems.

"A key to solving obesity problems among poor, urban children is to create safe and open spaces where these kids can play, because now we know that they are outside playing," said Rachel Kimbro, assistant professor of sociology at Rice University and lead author of the new study. "It's possible that children living in public housing have access to community playgrounds and courtyards for children to play outdoors, which could be why we see more outside play time for them."

Kimbro and her co-authors - Jeanne Brooks-Gunn of Columbia University and Sara McLanahan of Princeton University - also found that a mother's perception of her neighborhood's physical and social environment was a key predictor of how much her children would play outdoors. They measured mothers' perceptions of collective efficacy by asking them questions that gauged how likely the mother thought that neighbors would intervene in certain situations (such as if a child were skipping school and hanging out on the street) and whether mothers thought their neighborhoods were cohesive (such as people's willingness to help their neighbors).

Children of mothers who perceived higher levels of collective efficacy in their neighborhoods played outside for longer periods each day, watched less television and visited the park or playground more often each week.

The researchers tested whether subjective and objective neighborhood measures - socioeconomic status, type of dwelling, perceived collective efficacy and interviewer-assessed physical disorder of the immediate environment outside the home - were associated with children's activities.

"Maternal perceptions of neighborhood environments, both positive and negative, truly override objective measures, such as neighborhood poverty status, when considering children's activities," Kimbro said. "Given the importance of maternal perception, it becomes critical to create community-based programs that seek to facilitate trust and neighborhood social networks in these low-income, urban areas."

The data, collected through the Fragile Families and Child Well-being Study, represent more than 1,800 5-year-olds in 2003-2004 in urban areas of the U.S. Overall, 19 percent of the sample was overweight (between the 85th and 95th percentiles) and 16 percent was obese (above the 95th percentile).

Notes:

This study was funded by Active Living Research, a national program of the Robert Wood Johnson Foundation.

"Young Children in Urban Areas: Links Among Neighborhood Characteristics, Weight Status, Outdoor Play and Television-Watching" will be published in an upcoming issue of Social Science & Medicine and is available online.

 

Aetna Foundation To Fund Over $1 Million In Research To Deepen Understanding Of Obesity Epidemic

The Aetna Foundation announced significant funding in support of five research studies designed to deepen understanding of the root causes of the nation's well-documented obesity epidemic and drive viable solutions to the core problems. More than $1 million in funding will be granted in support of separate studies at New York University School of Medicine, Boston University, the University of Michigan, the University of Pennsylvania and Yale University's CARE program.

"While on its surface, the nation's obesity epidemic appears simple - we consume too many calories and don't get enough exercise - the issue is far more complex and the data available on what drives these unhealthy behaviors, particularly in urban, poor or minority communities, is scant," said Anne C. Beal, MD, MPH, president of the Aetna Foundation. "To help build the knowledge base and support development of effective policies that will foster healthier communities and a healthier nation, we are supporting these key research projects. These studies will consider issues such as the availability of broad food choices and the pricing of food, as well as the impact these factors have on individual food choices. The studies also will look at the role of our neighborhoods - and the impact of what is or isn't in the 'built environment' where we live, work and play-- on population health and weight loss."

Details on the grants announced today are as follows:

-- $250,000 to New York University School of Medicine for a two-year study of the impact of the introduction of supermarkets through tax credits and other incentives in areas that are classified as "food deserts." This study will examine the impact of the introduction of a supermarket on the local food environment in the Bronx, as well as the corresponding impact it may have on healthy eating habits of residents in local communities in the area, which include large Latino and African-American populations. The study will collect data on the eating patterns of 2,000 adults who are racially and ethnically diverse. Encouraging the introduction of supermarkets in food deserts through tax credits and other incentives is a growing strategy to address the problem of food deserts in some communities, but there is little data to support the effectiveness of this approach. Researchers at NYU hope to provide this critical insight to help shape federal, state and local policies.

-- $233,000 to Boston University's Slone Epidemiology Center for a two-year study of factors that influence obesity among African-American women, including both individual and neighborhood-level factors, and the identification of the most effective small changes individuals can make to decrease obesity rates among African-American women. Data from more than 20,000 participants in the ongoing Black Women's Health Study will be examined, including diet and exercise patterns, psychosocial stressors, and the neighborhood environment where the women live. Researchers hope to identify small, actionable changes women can take to reduce weight gain, and acquire evidence that will lead to policy and institutional level changes that can impact weight gain and obesity, such as neighborhood safety and walkability and grocery store accessibility.

-- $248,000 to the University of Michigan for a two-year study of how the built environment in an urban setting - in this case Detroit - may influence the risk of obesity among residents. The study seeks to identify specific features of the built and social environments that can be influenced to reduce racial and ethnic inequalities in obesity and related morbidity and mortality. The findings could inform the development of interventions and policies to promote health in urban communities. The study will bring together an interdisciplinary team of health researchers, urban planners, health service providers and community representatives and will build upon existing data sets compiled by the Healthy Environments Partnership.

-- $250,000 to the University of Pennsylvania's African American Collaborative Obesity Research Network for a one-year study of how variations in food prices influence food and beverage purchases among African-American women. The project will study the typical food shopping patterns in a sample of African-American women and seek to understand how food prices influence those patterns. Price variations for selected products at grocery stores within a defined geographical area will be analyzed in conjunction with data obtained from study participants to determine how price fits in with other considerations such as convenience and quantity when purchasing foods and beverages. Researchers hope to assess the potential for adjustments to food prices for high calorie-low nutrient foods and beverages to discourage their consumption and encourage the purchasing of healthier alternatives.

-- $150,000 to the Community Alliance for Research and Engagement (CARE) at Yale University for a study of the role of the neighborhood environment on childhood obesity risk factors and health outcomes. This study will look at a variety of built environment factors in six low-income, predominately minority neighborhoods in New Haven, as well as those factors closer to schools to see which of these might have a greater influence on the children's body mass index, diet and exercise. The study will also look at whether environmental factors have different effects on adults versus children.

The Aetna Foundation remains committed to targeted grant-making in three major areas which include addressing the rising incidence of obesity among U.S. residents, including children; promoting racial and ethnic equity in health and health care for common chronic conditions and infant mortality; and advancing integrated health care, by improving coordination and communications among health care professionals, creating informed and involved patients, and promoting cost-effective, affordable care.

 

Obesity And Diabetes May Be A Downside Of Human Evolution

New research in the FASEB Journal suggests that a gene called CMAH has been lost during the course of recent evolution, and may lead to an increased risk of Type 2 diabetes in humans

As if the recent prediction that half of all Americans will have diabetes or pre-diabetes by the year 2020 isn't alarming enough, a new genetic discovery published online in the FASEB Journal provides a disturbing explanation as to why: we took an evolutionary "wrong turn." In the research report, scientists show that human evolution leading to the loss of function in a gene called "CMAH" may make humans more prone to obesity and diabetes than other mammals.

"Diabetes is estimated to affect over 25 million individuals in the U.S., and 285 million people worldwide," said Jane J. Kim, M.D., a researcher involved in the work from the Department of Pediatrics at the University of California, San Diego in La Jolla, CA. "Our study for the first time links human-specific sialic acid changes to insulin and glucose metabolism and therefore opens up a new perspective in understanding the causes of diabetes."

In this study, which is the first to examine the effect of a human-specific CMAH genetic mutation in obesity-related metabolism and diabetes, Kim and colleagues show that the loss of CMAH's function contributes to the failure of the insulin-producing pancreatic beta cells in overweight humans, which is known to be a key factor in the development of type 2 diabetes. This gene encodes for an enzyme present in all mammalian species except for humans and adds a single oxygen atom to sialic acids, which are sugars that coat the cell surface.

To make their discovery, the researchers used two groups of mice. The first group had the same mutant CMAH gene found in humans. These mice demonstrated that the CMAH enzyme was inactive and could not produce a sialic acid type called NeuSGc at the cell surface. The second group had a normal CMAH gene. When exposed to a high fat diet, both sets of mice developed insulin resistance as a result of their obesity. Pancreatic beta cell failure, however, occurred only in the CMAH mutant mice that lacked NeuSGc, resulting in a decreased insulin production, which then further impaired blood glucose level control. This discovery may enhance scientific understanding of why humans may be particularly prone to develop type 2 diabetes. Results may also suggest that conventional animal models may not accurately mirror the human situation.

"The diabetes discovery is an important advance in its own right. It tells us a lot about what goes wrong in diabetes, and where to aim with new treatments," said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal, "but its implications for human evolution are even greater. If this enzyme is unique to humans, it must also have given us a survival advantage over earlier species. Now the challenge is to find the function of CMAH in defending us against microbes or environmental stress or both. This evolutionary science explains how we can win some and lose some, to keep our species ahead of the extinction curve."

Details:
Sarah Kavaler, Hidetaka Morinaga, Alice Jih, WuQiang Fan, Maria Hedlund, Ajit Varki, and Jane J. Kim. Pancreatic ß-cell failure in obese mice with human-like CMP-Neu5Ac hydroxylase deficiency. FASEB J. fj.10-175281; doi:10.1096/fj.10-175281.