Individual patient data meta-analysis of placebo-controlled trials of selective serotonin reuptake inhibitors submitted for regulatory approval in adult obsessive-compulsive disorder.

backgroundSelective serotonin reuptake inhibitors (SSRIs) are the preferred pharmacological treatment for obsessive-compulsive disorder (OCD). However, insufficient response is common and it remains unclear whether specific patient-level factors influence the likelihood of treatment response.

aimsTo determine the efficacy and acceptability of SSRIs in adult OCD, and to identify patient-level modifiers of efficacy.

methodsWe conducted an individual patient data meta-analysis (IPDMA) of industry-sponsored short-term, randomised, placebo-controlled SSRI trials submitted for approval to the Dutch regulatory agency to obtain marketing approval for treating OCD in adults. We performed a two-stage meta-analysis, using crude data of available trials. The primary outcome was the difference in Yale-Brown Obsessive-Compulsive Scale (YBOCS) change between active treatment and placebo. Secondary outcomes were differences in response (defined as the odds ratio of ≥35% YBOCS point reduction) and acceptability (defined as the odds ratio for all-cause discontinuation). We examined the modifying effect of baseline characteristics: age, gender, illness severity, depressive symptoms, weight, illness duration and history of antidepressant use.

resultsAfter excluding three trials because of missing data, we analysed results from 11 trials (79% of all submitted trials,

conclusionsOur IPDMA showed that SSRIs are well accepted and superior to placebo for treating OCD. The effects are modest and independent of baseline patient characteristics.