Background: The purpose of this study was to compare an early behavioral intervention (EBI) with nonstructured standard physical care (routine care intervention [RCI]) in preventing antipsychotic-induced weight gain in drug-naive first-episode psychosis patients.
Method: Sixty-one patients with a DSM-IV-diagnosed psychotic disorder were first randomly assigned to 3 different antipsychotic treatments (risperidone [N = 23], olanzapine [N = 18], and haloperidol [N = 21]) and subsequently randomly assigned to the intervention condition (EBI, N = 35) or RCI (N = 27). EBI was specifically designed to teach strategies to enhance control over factors associated with antipsychotic-induced weight gain and consisted of 8 flexible intervention modules that incorporated behavioral interventions, nutrition, and exercise. In the RCI group, patients were informed about potential weight gain and advised to increase their exercise and limit food intake. Body weight and body mass index were measured at baseline and then weekly for 3 months. In addition to change in weight and body mass index, a third outcome measure was the proportion of patients who had gained more than 7% of their body weight at 3 months. Participating patients were referred between August 2002 and September 2004.
Results: All 61 participants completed the study. Patients in the EBI group gained significantly less weight (mean = 4.1 kg, SD = 4.0) than those allocated to the RCI group (mean = 6.9 kg, SD = 4.5) (p < .01) during the 3-month follow-up period. Similar findings were obtained when both groups were compared on treatment-induced change in body mass index, which was significantly less in the EBI group than in the RCI group (1.40 vs. 2.39 kg/m2) (p < .01). Accordingly, significantly fewer patients in the EBI group (N = 11; 39.3%) than in the RCI group (N = 26; 78.8%) (p < .002) increased their baseline weight by more than 7%, the cutoff for clinically meaningful weight gain.
Conclusions: EBI was effective in attenuating antipsychotic-induced weight gain in a drug-naive first-episode psychosis cohort. Patients displayed good adherence to this type of preventive intervention.