Mirtazapine Versus other Antidepressive Agents for Depression

A Cochrane review [Abstract]1 included 29 RCT with a total of 4974 patients with depression. Both inpatients and outpatients were included in most of the trials. Participants were followed up for 6 weeks on average (range: 2 to 24 weeks) in a majority of the trials (n=15). In all but two trials HAM-D score was used for reporting the response.

• Mirtazapine vs. tricyclics (10 trials, n =1553): there was no difference in terms of response at two weeks (OR 0.85, 95% CI 0.64 to 1.13) or at the end of acute-phase treatment (at 6 to 12 weeks) (OR 0.89, 95% CI 0.72 to 1.10).
• Mirtazapine vs. SSRIs (12 trials, n = 2626): mirtazapine was significantly more effective at two weeks (OR 1.57, 95% CI 1.30 to 1.88) and at the end of acute-phase treatment (OR 1.19, 95% CI 1.01 to 1.39).
• Mirtazapine vs. SNRI (venlafaxine only; two trials, n = 415): mirtazapine was significantly more effective at two weeks (OR 2.29, 95% CI 1.45 to 3.59) and at the end of acute-phase treatment (OR 1.53, 95% CI 1.03 to 2.25).

Mirtazapine is less likely to cause tremor than TCAs, and nausea and sexual dysfunction than SSRIs, but causes more likely weight gain and somnolence.

Comment: The quality of evidence is downgraded by study quality (inadequate allocation concealment, short follow-up time, more than 20 % drop-out) and indirectness (the majority of trials were not conducted for refractory depression or for elderly people, none of the trials assessed general functioning or quality of life).

References

• Watanabe N, Omori IM, Nakagawa A et al. Mirtazapine versus other antidepressive agents for depression. Cochrane Database Syst Rev 2011;12:CD006528. [PubMed]