Risk factors for bulimia nervosa. A community-based case-control study.
Fairburn CG., Welch SL., Doll HA., Davies BA., O'Connor ME.
BACKGROUND: Many apparently disparate risk factors have been implicated as causes of eating disorders. This study was designed to test the hypothesis that 2 broad classes of risk factors exist for bulimia nervosa: those that increase the risk for development of a psychiatric disorder in general and those that increase the risk of dieting. It was predicted that the latter are especially common among persons with bulimia nervosa. METHODS: A case-control design was used involving 2 integrated comparisons. First, 102 subjects with bulimia nervosa were compared with 204 healthy control subjects without an eating disorder. Second, the same 102 subjects with bulimia nervosa were compared with 102 subjects with other psychiatric disorders. To reduce sampling bias, the subjects were recruited directly from the community. A broad range of putative risk factors was assessed. RESULTS: The subjects with bulimia nervosa and the healthy control subjects differed in their rates of exposure to most of the putative risk factors. Far fewer differences were evident between the subjects with bulimia nervosa and the control subjects with other psychiatric disorders, although exposure to factors that were likely to increase the risk of dieting and to negative self-evaluation and certain parental problems (including alcohol use disorder) were substantially more common among those with bulimia nervosa. CONCLUSIONS: The findings support the hypothesis that bulimia nervosa is the result of exposure to general risk factors for psychiatric disorder and risk factors for dieting. An unexpected finding was the particularly high rates of premorbid negative self-evaluation and certain parental problems among those with bulimia nervosa.