Gender-based clinical differences in evidence-based treatment for adolescent anorexia nervosa: analysis of aggregated randomized controlled trials.

PURPOSE: Boys represent a small proportion of samples in randomized clinical trials (RCT) investigating evidence-based treatment for adolescents with anorexia nervosa (AN). Consequently, knowledge of potential gender differences in clinical characteristics and treatment response in adolescents is considerably limited. METHODS: Secondary analyses of aggregated data from two RCTs were used to characterize baseline and end-of-treatment clinical features in male and female adolescents with AN (n = 228, 10.53% male). Mixed analyses of variance were used to investigate potential gender differences in treatment response relative to weight outcomes (% median BMI) and eating disorder cognitions (Eating Disorder Examination Global scores; EDE). RESULTS: There were no significant gender differences in prior inpatient care, illness duration, psychiatric comorbidity, or psychotropic medication use at baseline. Nor were there significant gender differences in binge eating, purging, or driven exercise at baseline or end-of-treatment. Girls reported elevated weight and shape concern compared to boys at baseline but overall reduction in EDE Global scores over the course of treatment did not differ according to gender. Boys gained more relative weight during treatment than girls, but this difference was statistically non-significant. CONCLUSION: Overall findings do not suggest significant differences in treatment outcome relative to weight or ED cognitions, by gender. Current evidence suggests that, with the exception of shape and weight concerns, boys present with cognitive and behavioral symptoms as severe as their female counterparts which underscores the need for increased accuracy in assessment of these disorders in boys and young men. LEVEL OF EVIDENCE: Level 1, secondary data analysis of randomized controlled trials.