Background: The effects of extended selective serotonin reuptake inhibitor (SSRI) treatment on weight are not well characterized. Also unknown is whether different agents have differential effects. To examine these questions, we assessed weight changes in patients randomly assigned to long-term treatment with fluoxetine, sertraline, or paroxetine.
Method: Patients (N = 284) with major depressive disorder (DSM-IV) were randomly assigned to double-blind treatment with fluoxetine (N = 92), sertraline, (N = 96), or paroxetine (N = 96) for a total of 26 to 32 weeks. The mean percent change in weight was compared for each group, as was the number of patients who had > or = 7% weight increase from baseline.
Results: Patients (fluoxetine, N = 44; sertraline, N = 48; paroxetine, N = 47) who completed the trial were included in these analyses. Paroxetine-treated patients experienced a significant weight increase, fluoxetine-treated patients had a modest but nonsignificant weight decrease, and patients treated with sertraline had a modest but nonsignificant weight increase. The number of patients whose weight increased > 7% from baseline was significantly greater for paroxetine-treated compared with either fluoxetine-treated or sertraline-treated patients.
Conclusion: Risk of weight gain during extended SSRI treatment differs depending on which SSRI is used.