Sleep disturbance is common in depression and is a risk factor for recurrence and suicide. This analysis evaluated the effects of adjunct extended-release quetiapine fumarate (quetiapine XR) on sleep disturbance and quality in patients with major depressive disorder (MDD) and an inadequate response to on-going antidepressant therapy. Pooled data from two 6-wk, randomized, double-blind, placebo-controlled trials were analysed post hoc. Patients received once-daily quetiapine XR [(150 mg/d), n = 309; (300 mg/d), n = 307] or placebo (n = 303) adjunct to on-going antidepressant therapy. Analyses included: change from randomization in Montgomery-Åsberg Depression Rating Scale (MADRS) Item 4 (reduced sleep) score; Hamilton Rating Scale for Depression (HAMD) Items 4 (insomnia-early), 5 (insomnia-middle) and 6 (insomnia-late) scores; HAMD sleep disturbance factor (Items 4+5+6); Pittsburgh Sleep Quality Index (PSQI) global score. Change in MADRS total score was also evaluated in patients stratified by HAMD sleep disturbance factor score (high ≥ 4 and low < 4) at randomization. At week 6, adjunct quetiapine XR (150 and 300 mg/d) reduced MADRS Item 4, HAMD Items 4, 5 and 6, HAMD sleep disturbance factor and PSQI global scores from randomization vs. placebo (all p < 0.001). In patients with high sleep disturbance, quetiapine XR (both doses) improved depressive symptoms (MADRS total score) vs. placebo from week 1 onwards (p < 0.01). Adjunct quetiapine XR improved sleep disturbance and quality vs. placebo in patients with MDD and an inadequate response to on-going antidepressant treatment, and was effective against depressive symptoms in patients experiencing high sleep disturbance.
Trial registration: ClinicalTrials.gov NCT00326105 NCT00351910.