Chapter 37 Obesity
INTRODUCTION
Description: Obesity is a state of increased fat and lean body mass (>20% higher ideal weight, body mass index [BMI] >28) associated with increased health risks. Obesity affects more women than men and is of special concern to adolescents and older women. Weight gained during pregnancy (in excess of that related to the pregnancy) is often not lost.
ETIOLOGY AND PATHOGENESIS
Causes: Calorie consumption in excess of expenditure, insulinoma, hypothalamic disorders, Cushing’ syndrome, corticosteroid drugs.
DIAGNOSTIC APPROACH
Workup and Evaluation
Laboratory: No evaluation indicated. Consider thyroid testing in selected patients. Determine serum cholesterol, triglycerides, or glucose levels to assess risk factors for complications.
Special Tests: Body mass index = weight (kg)/height (m2), waist to hip circumference ratio (normal female gynecoid pattern is greater than 0.85).
MANAGEMENT AND THERAPY
Nonpharmacologic
General Measures: Risk assessment, diet and exercise counseling. Assistance with diet planning or selection of a commercial program.
Specific Measures: Behavior modification and hypnosis have been applied with variable success. In select patients (body mass index >40) surgical intervention (stapling or bypass) may be indicated. Surgery is the most effective long-term therapy for morbid obesity.
Diet: Restriction to 500 kcal below maintenance generally provides the best sustainable loss (1 lb/week). Verylow-calorie diets are associated with increased risk and occasional deaths.
