Olanzapine improves weight in adult outpatients with anorexia nervosa
Olanzapine confers a modest therapeutic effect on weight compared with placebo in adult outpatients with anorexia nervosa, a study has shown. However, it does not appear to offer significant benefit for psychological symptoms.
“Nevertheless, the finding on weight is notable, as achieving change in weight is notoriously challenging in this disorder,” the authors noted.
This randomized double-blind placebo-controlled trial conducted at five sites in North America assessed the benefits of olanzapine vs placebo for adult outpatients with anorexia nervosa.
A total of 152 participants (96 percent women; mean body mass index [BMI], 16.7 kg/m2) were randomly assigned in a 1:1 ratio to receive either olanzapine (n=75) or placebo (n=77). They were observed weekly for a 16-week period. The primary outcome measures were rates of change in body weight and change in obsessionality, assessed with the Yale-Brown Obsessive-Compulsive Scale (YBOCS).
Findings showed a statistically significant treatment-by-time interaction, which suggested that the increase in BMI over time was higher in patients in the olanzapine group (0.259 vs 0.095 per month) than in those in the placebo group.
No significant between-group difference was observed in change in the YBOCS obsessions subscale score over time (–0.325 vs –0.017 points per month). In addition, no significant between-group differences were seen in the frequency of abnormalities on blood tests assessing potential metabolic disturbances.
A small study in 2011 reported that olanzapine was more effective than placebo and was generally well tolerated by outpatients with anorexia nervosa. [Psychol Med 2011;41:2177-2182]