Table 26-5summarizes treatment approaches to obesity.
Surgical procedures, such as intestinal bypass operations and gastric stapling, are effective in producing weight loss and in improving psychosocial functioning. These surgical procedures may also produce biological change, perhaps by lowering the body weight set point. However, risks of surgery and anesthesia, which are greater in obese individuals, plus the possibility of postoperative complications such as malabsorption syndromes following bypass procedures should limit the indications for these interventions to the treatment of massive and morbid obesity that has not responded to conservative management. Wiring the jaws shut to prevent the intake of solid food may help some individuals, particularly when used in preparation for surgery. The use of intragastric balloons, a noninvasive method of gastric restriction, may also be effective. It should be noted that surgical interventions are never curative by themselves, as many patients regain the weight they lose within 2 years of the procedures.
Amphetamines were once widely prescribed as anorexigenic agents in the treatment of obesity. However, their high potential for abuse limits their use as diet aids. Furthermore, tolerance develops easily. Anorexigenic drugs with low abuse potential include sibutramine, diethylpropion, phentermine, and ma-zindol. Their effectiveness is modest and side ef-fects, primarily anxiety and insomnia, are comparable.
The combination of the serotonin enhancer fenflur-amine with the sympathomimetic amine phenter-mine was widely prescribed in the mid 1990s. The practice of prescribing “fen-phen” was abruptly halted in 1997 with the discovery of heart valve lesions in a large number of these patients. Fenflur-amine has since been withdrawn from the market, and although phentermine remains available, it should not be combined with other serotonin-enhancing agents. Given the limited efficacy and significant risks of appetite suppressants, their use should be limited to patients who are significantly overweight (BMI greater than 30) and they should be used only for brief periods of time.
Other selective serotonin reuptake inhibitors may also be useful in the treatment of obesity, particularly with patients who engage in binge eating and who have coexisting affective disorders. Hope for the future may also lie with a new class of drugs called lipase inhibitors, which act directly on the gastrointestinal tract to block the absorption of fat.
Exercise regimens are recommended as part of most treatment plans. Exercise is helpful not only because of the increase in caloric expenditure but because physical activity (in otherwise sedentary individuals) is associated with decreased appetite and increased basal metabolism. This latter effect may offset the estimated 15-30% decrease in basal metabolic rate that occurs with caloric restriction and weight loss from dieting. Exercise also increases the proportion of weight loss from fat as opposed to lean body tissue. Exercise combined with low-calorie diets will result in weight loss; the difficulty, of course, is in motivating patients to comply with a disciplined regimen.
Support groups such as Overeaters Anonymous and Weight Watchers may be helpful in motivating some individuals to lose weight. In recent years, behavior modification programs have been shown to be effective in reducing the high dropout rate associated with most weight reduction programs, particularly when deposits of money are required and sums are refunded with regular attendance or weight loss. Behavioral programs have been shown to be effective in the short run, but weight tends to be regained. Psychoanalysis and psychoanalytically oriented psychotherapy have not traditionally been regarded as being effective in the treatment of obesity. In their classic 1983 study, Rand and Stunkard suggest a more optimistic outlook. Of 84 men and women treated by 72 psychoanalysts, 72 had weight losses comparable to what was achieved by other methods, even though only about 6% of obese persons who entered treatment did so because of their obesity. Analysts also reported dramatic improvements in body image perceptions in their patients. Whereas 40% of obese patients showed marked body image disturbances at the start of treatment, only 14% continued to have such problems at termination. This study suggests that psychoanalytic psychotherapy may be effective in some cases, particularly for patients with disturbances of body image and self-concept.
Abnormal eating behavior may arise as an attempt to calm and soothe unpleasant emotions, as an effort to resolve intrapsychic conflicts around aggression, sexuality, and interpersonal relationships, or as an attempt to act out issues on behalf of a dysfunctional family. Biological factors may play a role by directly affecting the physiology of fat accumulation or indirectly by predisposing to affective disorders (anxiety and depression) commonly associated with eating disorders. Cultural factors such as society’s preoccupation with youth and thinness also play a major role. Eating disorders clearly provide a clinical paradigm for the biopsychosocial model.
Revision date: July 9, 2011
Last revised: by Sebastian Scheller, MD, ScD