Background: The aim was to compare the efficacy
and tolerability of mirtazapine with those of paroxetine.
Method: 275 outpatients with a diagnosis of
major depressive episode (DSM-IV) and a score >= 18 on the
17-item Hamilton Rating Scale for Depression (HAM-D-17) were
randomly assigned to 6 weeks of treatment with mirtazapine (15-45
mg/day) or paroxetine (20-40 mg/day). Efficacy was assessed by
the HAM-D-17, Hamilton Rating Scale for Anxiety (HAM-A), and
Clinical Global Impressions scales (Severity and Improvement),
and analyses were performed on the intent-to-treat sample (127
mirtazapine-treated patients and 123 paroxetine-treated
patients).
Results: Mean daily doses were 32.7 mg of
mirtazapine and 22.9 mg of paroxetine. Thirty patients in the
mirtazapine group and 33 in the paroxetine group dropped out.
Both drugs were equally effective in reducing symptoms of
depression. At week 1, the mean HAM-D-17 total score was
significantly lower in mirtazapine- than paroxetine-treated
patients (16.5 vs. 18.8, p = .0032). Similarly, significantly
more mirtazapine-treated patients were HAM-D-17 responders (>=
50% decrease from baseline) at weeks 1 (23.2% vs. 8.9%, p = .002)
and 4 (58.3% vs. 44.5%, p = .04). Both treatments were equally
effective in reducing anxiety. However, the reduction in mean
HAM-A total score was significantly greater with mirtazapine than
with paroxetine at week 1 (-5.1 vs. -3.5, p = .0435).
Tolerability of both treatments was good, with more nausea,
vomiting, tremor, and sweating in the paroxetine group and more
weight increase and influenza-like symptoms in the mirtazapine
group.
Conclusion: Mirtazapine and paroxetine
were equally effective after 6 weeks of therapy and were both
well tolerated. A potentially faster onset of overall therapeutic
efficacy of mirtazapine was suggested by significant differences
between treatments after 1 week of therapy that were due to
slightly larger improvements of several core symptoms of
depression as well as distinct prevention of treatment-emergent
worsening of anxiety and physical components of depression.
J Clin Psychiatry 2000;61(9):656-663
© Copyright 2000 Physicians Postgraduate Press, Inc.