Sexual function during long-term duloxetine treatment in patients with recurrent major depressive disorder

Introduction: Sexual dysfunction (SD) is frequently associated with major depressive disorder (MDD) in the untreated state and may be worsened by antidepressant treatment.

Aim: We evaluated SD in duloxetine-treated patients during an MDD recurrence prevention study.

Method: Patients (N = 514) received open-label duloxetine 60-120 mg/day for up to 34 weeks. Responders (N = 288) were randomly assigned to duloxetine or placebo during a further 52-week double-blind maintenance phase.

Main outcome measures: The Arizona Sexual Experience Scale (ASEX) was used to assess sexual functioning.

Results: At study entry, 73.4% of patients met ASEX criteria for SD. After open-label duloxetine treatment, the probability of continued SD was 77.9% for nonresponders and 53.2% for responders. In patients without SD at study entry, the probability of emergent SD was 49.6% (nonresponders) and 33.2% (responders). In the double-blind maintenance phase, there was no significant difference (P = 0.105) in the probability of emergent SD between placebo-treated (49.2%) and duloxetine-treated (27.9%) patients without SD at baseline, with no significant treatment-by-gender interaction. In patients with a recurrence of MDD, the probability of emergent SD was similar between placebo- (71.3%) and duloxetine-treated (82.7%) patients. However, in patients with no recurrence of MDD, the probability of emergent SD in placebo patients (40.0%) was numerically higher than in duloxetine patients (12.9%). Spontaneous reports of adverse events related to sexual function were infrequent and no patients discontinued due to these events.

Conclusions: In patients with MDD, the probability of continued or emergent SD after up to 34 weeks of open-label duloxetine treatment was associated with the response status of the patients. In patients who responded to duloxetine treatment, after up to a further 52 weeks of double-blind treatment either with duloxetine or placebo, the probability of continued or emergent SD appeared to be more related to MDD itself than the treatments that the patients received.