Sexual dysfunction in patients with antidepressant-treated anxiety or depressive disorders: A pragmatic multivariable longitudinal study

Objective: To investigate early evolution, tolerability, and predictors of antidepressant-emergent sexual dysfunction in patients with anxiety or depressive disorder. Methods: Patients with anxiety or depressive disorders who were prescribed antidepressant monotherapy (mirtazapine, sertraline, desvenlafaxine, escitalopram, or fluoxetine) at the discretion of the treating clinician were recruited from July 2012 to June 2014 from a hospital outpatient service. All were free of psychotropic medication for least 1 month. Sexual function was assessed at baseline, week 2, and week 6 using the Psychotropic-Related Sexual Dysfunction Questionnaire (PRSexDQ). A PRSexDQ score of ≥ 2 was considered to indicate sexual dysfunction. Sexual function was dichotomised to 'favourable' or 'impaired'. Results: Of 230 patients recruited, 209 were assessed at baseline of whom 184 were assessed at week 2; of these, 154 were also assessed at week 6. At baseline, 138 (66%) of the 209 patients were diagnosed with depressive disorder and 71 (34%) with anxiety disorder; 29% of patients had sexual dysfunction (in any domain of PRSexDQ). By week 6, the percentage had increased to 41%, although the change in the mean PRSexDQ score was only marginal (from 1.04 at baseline to 1.55 at week 6). With regard to individual questionnaire items, by week 6, sexual desire improved, but erectile and ejaculatory function in men and orgasmic function in women worsened. Fluoxetine and sertraline were associated with impaired sexual function, whereas mirtazapine was associated with favourable sexual function. In a logistic regression analysis, at week 2, mirtazapine and desvenlafaxine were predictors of favourable sexual outcome, whereas fluoxetine and higher baseline PRSexDQ score were predictors of impaired sexual outcome. At week 6, mirtazapine remained a predictor of favourable sexual outcome, whereas fluoxetine, higher 2-week PRSexDQ score, and adequate dose were predictors of impaired sexual outcome. Conclusions: In patients with anxiety or depressive disorder, the risk of antidepressant-emergent sexual dysfunction at 6 weeks is low when drug doses are initially low with gradual up-titration. Baseline sexual dysfunction was independently associated with impaired sexual outcome. Men may be more likely than women to experience impaired sexual outcome. In patients with baseline sexual dysfunction, prescription of mirtazapine might be preferable to fluoxetine.