Epidemiology of obesity, pathophysiology, associated disease and management

Due to the gastrointestinal tract's role in body weight regulation, gastroenterologists should work closely with other medical disciplines to oversee and coordinate the care of obese individuals, according to an American Gastroenterological Association (AGA) Institute Obesity Task Force Report.

The Report was published in a special 13th issue of Gastroenterology, the official journal of the AGA Institute, that focuses on the growing problems related to obesity and nutrition. The special issue of Gastroenterology presents a series of articles on the epidemiology of obesity, pathophysiology, associated disease and management.

An estimated 1.6 billion adults worldwide are overweight (body mass index [BMI]>25) and 400 million are obese (BMI>30), and potentially as many 20 million children are overweight. As obesity becomes an increasingly global problem, it is harder for government, institutions and individuals to continue to consider obesity as a problem of personal choice that can be controlled and even reversed by deciding to eat less and exercise more. The incidences of diabetes and other debilitating diseases attributable to obesity continue to rise along with the negative impact on healthcare budgets and various sectors of the economy leading to changing attitudes about the obesity epidemic.

"As the AGA Institute Obesity Task Force examined the current and potential roles of the gastroenterology community in addressing the severe worldwide problem of obesity and its complications, we were encouraged to find a growing commitment to obesity-related research and development within the federal government, pharmaceutical and medical device industries," according to Lee M. Kaplan, MD, PhD, co-chair of the Obesity Task Force and director, Massachusetts General Hospital Weight Center.

A better understanding of the origins and development of obesity provides a framework for evidence-based treatment the disease. As new and exciting research continues into the causes, prevention and treatments for obesity, the role played by the gastrointestinal (GI) tract is becoming more defined. This understanding will lead to novel endoscopic, pharmacological and nutritional therapies for obesity as well as changes in policies and societal practices related to obesity.

"Due to the widespread effects of obesity on a person's health, it is urgent that the AGA Institute collaborates with other leading medical organizations to encourage a multidisciplinary approach to the treatment of our patients to most affectively address their health needs," said Dr. Kaplan.

The research found in this special issue of Gastroenterology was chosen to emphasize the multidimensional problems of obesity and to outline the integrated approach needed to understand the extent of the problem, causes and health and socioeconomic consequences of obesity. Several papers of note include:

• "The Epidemiology of Obesity" - Katherine M. Flegal, PhD, National Center for Health Statistics, and colleagues review the epidemiology of obesity, highlighting controversies surrounding adiposity (quality or state of being fat) measurement, ethnic differences, childhood obesity and diseases associated with obesity.
• "Gut Hormones and Appetite Control" - Stephen R. Bloom, MD, Imperial College of London and colleagues review the role played by gut hormones in appetite and weight by regulating when and how much individuals eat for every meal.
• "Obesity, Inflammation and Insulin Resistance" - Steven E. Shoelson, MD, PhD, Joslin Diabetes Center and Harvard Medical School and colleagues discuss the potential roles for inflammation in the development of insulin resistance and type 2 diabetes.
• "The Role of Obesity and Related Metabolic Disturbances in Cancers of the Colon, Prostate and Pancreas" - Edward Giovannucci, MD, Harvard School of Public Health, and colleagues review the evidence for and against a connection between obesity and cancers of the colon, prostate and pancreas, and offers possible mechanisms.
• "Lifestyle Modification for the Management of Obesity" - Thomas A. Wadden, MD, PhD, University of Pennsylvania, and colleagues discuss the importance of and strategies for lifestyle modification for the treatment of obesity, including the effectiveness of various diets, exercise and behavioral therapies.
• "Drug Treatment and the Overweight Patient" - George A. Bray, MD, Pennington Biomedical Research Center, and colleagues discuss drug treatments for overweight patients including currently available and impending treatments.
• "Bariatric Surgery: A Review of Procedures and Outcomes" - Bruce M. Wolfe, MD, Oregon Health & Science University, and colleagues discuss surgical procedures for weight loss, criteria for patient selection and outcomes.
• "AGA Institute Obesity Task Force" Report - Lee M. Kaplan, MD, PhD, Harvard Medical School and co-chair of the Obesity Task Force, and colleagues present the findings and recommendations of the Task Force based on the papers presented in Gastroenterology.

"We believe the papers presented in this issue of Gastroenterology provide a comprehensive picture of the current thinking and research in overweight and obesity," according to Dr. Kaplan. "We hope that all medical disciplines reviewing this report gain a better understanding of the disease that will help them in the treatment of their patients."