Comparison of weight changes in patients treated with different antidepressants: clinical experiences in Taiwanese patients.

BACKGROUND Psychiatric patients are more likely to gain weight when prescribed antipsychotics or antidepressants. Studies on these issues in Taiwan are scarce. This study compared weight changes in patients treated with NaSSA (Noradrenergic and Specific Serotonergic Antidepressant) and SSRIs (Selective Serotonin Reuptake Inhibitors), and investigated possible associated factors. METHODS An observational, non-randomized study was conducted on all patients diagnosed with depression attending the out-patient's clinic at a general hospital. Patients treated with NaSSA or SSRIs were monitored for 24 weeks. RESULTS Forty-Seven patients (27 patients on NaSSA and 20 on SSRIs) completed the study. Patients taking NaSSA gained an average of 1.87 kg (SD: 4.14, median: 1.0, range: -3.5 to 11.0) at the end of the study, compared to 1.83 kg (SD: 3.78; median: 1.5, range: -7.0 to 8.0) for the SSRIs group. No statistically significant difference existed between the two groups. However, patients who had never previously been treated with either SSRIs or NaSSA exhibited significantly greater weight gain (4.84 kg, SD: 3.20, median: 4.75, range: 0 to 11.0) than those who had previously been treated (-0.78 kg, SD: 2.36, median: -0.5, range: -7.0 to 3.5). Low initial body mass index and concomitant medications also seemed to be linked to weight gain. CONCLUSION Significant weight gain occurred in those patients who had not been previously treated with NaSSA or SSRIs. Patients should be informed of this possibility before initiating treatment, especially those with low body mass index and those prescribed co-medications. Furthermore, the treatment program should include weight monitoring, nutritional assessment and counseling.