Bulimia nervosa in a Canadian community sample: prevalence and comparison of subgroups

TLDR

Epidemiological studies of bulimia nervosa report varying incidence and prevalence estimates due to differing definitions and methodologies. The study aimed to determine bulimia nervosa prevalence in a community sample, assess DSM‑III‑R threshold criteria, and examine comorbidity. The authors used a structured WHO Composite International Diagnostic Interview on 8,116 Ontario residents, adding bulimia‑specific questions, and compared full‑syndrome cases to partial‑syndrome cases lacking the frequency criterion. Lifetime prevalence was 1.1% in females and 0.1% in males, and bulimic individuals—both full and partial syndromes—showed higher rates of mood and anxiety disorders, alcohol dependence, parental psychopathology, and childhood sexual abuse, supporting existing prevalence estimates and highlighting the arbitrariness of the binge‑eating frequency threshold.

Abstract

Previous epidemiological studies of bulimia nervosa have generated differing estimates of the incidence and prevalence of the disorder. These differences are attributable, in part, to varying definitions of the illness and a range of methodologies. The authors sought to define the prevalence of bulimia nervosa in a nonclinical community sample, examine the clinical significance of DSM-III-R threshold criteria, and examine comorbidity.Subjects across Ontario (N = 8,116) were assessed with a structured interview, the World Health Organization Composite International Diagnostic Interview, with specific questions added for bulimia nervosa. Subjects who met DSM-III-R criteria for bulimia nervosa were compared with those who were missing only the frequency criterion (two or more binge-eating episodes per week for 3 months).In this sample, the lifetime prevalence of bulimia nervosa was 1.1% for female subjects and 0.1% for male subjects. The subjects with full- and partial-syndrome bulimia nervosa showed significant vulnerability for mood and anxiety disorders. Lifetime rates of alcohol dependence were high in the full-syndrome group. Rates of parental psychopathologies were high in both bulimic groups but tended to be higher in the subjects with full-syndrome bulimia nervosa. Both bulimic groups were significantly more likely to experience childhood sexual abuse than a normal female comparison group.This study confirms other prevalence estimates of bulimia nervosa and its comorbid diagnoses from studies that were based on sound methodologies. It also points to the arbitrary aspects of the frequency of binge eating as a diagnostic threshold criterion for the disorder.