Treating Obesity with Drugs and Surgery: A Clinical Practice Guideline from the American College of Physicians

Summaries for Patients are a service provided by Annals to help patients better understand the complicated and often mystifying language of modern medicine.

Summaries for Patients are presented for informational purposes only. These summaries are not a substitute for advice from your own medical provider. If you have questions about this material, or need medical advice about your own health or situation, please contact your physician. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the American College of Physicians.

The summary below is from the full reports titled "Pharmacologic and Surgical Management of Obesity in Primary Care: A Clinical Practice Guideline from the American College of Physicians," "Meta-Analysis: Pharmacologic Treatment of Obesity," and "Meta-Analysis: Surgical Treatment of Obesity." They are in the 5 April 2005 issue of Annals of Internal Medicine (volume 142, pages 525-531, pages 532-546, and pages 547-559, respectively). The first paper was written by V. Snow, P. Barry, N. Fitterman, A. Qaseem, and K. Weiss, for the Clinical Efficacy Assessment Subcommittee of the American College of Physicians; the second paper was written by Z. Li, M. Maglione, W. Tu, W. Mojica, D. Arterburn, L.R. Shugarman, L. Hilton, M. Suttorp, V. Solomon, P.G. Shekelle, and S.C. Morton; and the third paper was written by M.A. Maggard, L.R. Shugarman, M. Suttorp, M. Maglione, H.J. Sugerman, E.H. Livingston, N.T. Nguyen, Z. Li, W.A. Mojica, L. Hilton, S. Rhodes, S.C. Morton, and P.G. Shekelle.

Who developed these guidelines?

The American College of Physicians (ACP) developed these recommendations. Members of ACP are internal medicine doctors, specialists in the care of adults.

What is the problem and what is known about it so far?

Obesity leads to health problems, and obese people die younger than normal-weight people. Body mass index (BMI) is a measure of the appropriateness of a person's weight. To calculate BMI, you divide weight in kilograms by the square of height in meters (BMI = weight in kilograms/height in meters²). A BMI calculator is available at http://www.nhlbisupport.com/bmi. People with BMIs of 25 kg/m² to 29.9 kg/m² are overweight, and people with BMIs of 30 kg/m² or more are obese. Treatment for obesity begins with changes in diet and exercise. However, for some patients, obesity drugs or surgery may be appropriate.

How did the ACP develop these recommendations?

The authors reviewed studies about drugs and surgical procedures used to treat obesity. They identified the weight loss and side effects that patients can expect with these treatments. These guidelines apply only to persons with BMIs of 30 kg/m² or more.

What did the authors find?

Studies of obesity drugs had limitations such as short duration, few patients, and many patients who did not complete the study. After taking a weight loss drug for 6 to 12 months, patients lost about 11 lb or less. Previous studies have shown that this modest amount of weight loss can improve diabetes control, blood pressure, and cholesterol levels.

Many studies of obesity surgery had limitations such as no comparison group, but they suggested that patients can lose 44 to 67 lb and keep it off for up to 10 years. Weight loss after surgery has been associated with improvements in diabetes, blood pressure, and cholesterol level. However, studies suggest that up to 1.9 of every 100 patients may die because of a surgical complication. There are no studies to determine whether one of the many obesity surgery procedures is better than another, but outcomes of obesity surgery are best at centers that do many of these procedures.

What does the ACP suggest that patients and doctors do?

Doctors should counsel all obese patients about diet and exercise. Doctors and patients should identify goals for weight loss, blood pressure, and blood sugar. Doctors and obese patients may consider obesity drugs when patients are unable to reach their goals with diet and exercise alone. Patients should understand the potential side effects and the lack of long-term studies of the effectiveness and safety of obesity drugs. Available obesity drugs include sibutramine, orlistat, phentermine, diethylpropion, fluoxetine, and bupropion. Doctors and patients should discuss the side effect profile of each medication to determine which drug would be best for an individual patient.

Doctors should discuss surgery with obese patients who have BMIs of 40 kg/m² or higher along with obesity-related conditions such as high blood pressure, diabetes, or sleep apnea. Patients should understand that the possible side effects of obesity surgery include surgical complications, gall bladder disease, and difficulties with digestion. Doctors and patients considering obesity surgery should seek surgeons and surgical centers with high levels of experience.

What are the cautions related to these recommendations?

Diet and exercise remain essential to the treatment of obesity, even for patients who choose medications or surgery. Recommendations may change as additional studies become available.