People with eating disorders have nine times greater risk for lifetime OCD

Individuals with eating disorders had nearly nine times greater risk for lifetime OCD and eight times greater risk for current OCD vs. healthy controls, according to results of an epidemiological meta-analysis.

“Despite differences in how obsessions and compulsions are experienced across the disorders, the purpose of the obsessive and compulsive behaviors observed in both [eating disorders] and OCD is to reduce levels of apprehension, anxiety and overall negative affect,” Dalainey H. Drakes, of the department of psychology at the Memorial University of Newfoundland in Canada, and colleagues wrote in Journal of Psychiatric Research. “Therefore, it may be that common etiological factors explain the high comorbidity between these conditions.”

Via meta-analysis, the investigators sought to precisely estimate OCD prevalence among individuals with a current primary eating disorder diagnosis, as well as to isolate its predictors. They searched two databases using a Boolean search phrase that incorporated keywords related to OCD, eating disorders, comorbidity, prevalence and epidemiology. They also utilized references coded from related review articles and experts in the field. They included articles that reported an observational study assessing current eating disorder diagnoses, used a semi-structured or structured diagnostic interview for OCD and eating disorder diagnosis, used DSM or ICD criteria, had adolescent or adult samples, had patient or community samples and reported comorbidity for lifetime or current OCD.

Drakes and colleagues identified 846 articles and calculated 35 lifetime and 42 current estimates. They extracted OCD prevalence from each study for each eating disorder diagnostic category, as well as 11 further possible moderators.

Results showed an aggregate lifetime OCD prevalence of 13.9% (95% CI, 10.4-18.1) and current OCD prevalence of 8.7% (95% CI, 5.8-11.8) across eating disorders. Anorexia nervosa binge-eating purging type had the greatest prevalence of and risk for OCD in eating disorders, moderator analyses showed. OCD prevalence was greater among patient samples than samples recruited from the community. Those with eating disorders had 8.9 times greater risk for lifetime OCD and eight times greater risk for current OCD compared with healthy controls.

“Additional research exploring how treatment can best be tailored to target common etiological factors across eating disorder subtypes and OCD subtypes is also essential to improve how treatment plans are devised for these conditions,” the researchers wrote.