Managing Atypical Antipsychotic-Associated Weight Gain: 12-Month Data on a Multimodal Weight Control Program

Background: The purpose of this study was to test prospectively the feasibility and efficacy of a multimodal weight control program for overweight and obese severely mentally ill adults who had gained weight while taking atypical antipsychotic medications.

Method: Thirty-one subjects with schizophrenia or schizoaffective disorder (DSM-IV), on treatment with atypical antipsychotics, participated in a 52-week, multimodal weight control program that incorporated nutrition, exercise, and behavioral interventions. The primary outcomes were measures of body mass index (BMI) and weight. A variety of secondary outcomes, including hemoglobin A_1c level, systolic and diastolic blood pressure, and cholesterol level, were compared from baseline to endpoint. Weight and BMI changes in the intervention group were also compared with changes in 20 nonintervention patients (“usual care” group) who were contemporaneously treated in the same clinics.

Results: Twenty of the 31 subjects in the intervention group completed the program. Statistically significant pre-post improvements in weight (p < .02), BMI (p < .02), hemoglobin A_1c levels (p < .001), diastolic (p < .001) and systolic (p < .05) blood pressure, exercise level (p < .003), nutrition knowledge (p < .0001), and stage of change (exercise [p < .0001] and weight [p < .008]) were seen in the intervention group. Patients attended a mean of 69% of the sessions during the year of the program. Weight and BMI also decreased significantly (p = .01) in the intervention group compared with the "usual care" group, who gained weight during the observation period.

Conclusions: Individuals with schizophrenia and schizoaffective disorder were willing to attend, and benefited from, a weight control program that focused on nutrition, exercise, and motivation. The program resulted in clinically significant reductions in weight, BMI, and other risk factors for long-term poor health, including hemoglobin A_1c. In contrast, patients who did not receive the weight control intervention continued to gain weight.