Efficacy and safety of each class of sleep medication for major depressive disorder with insomnia symptoms: A systematic review and meta-analysis of double-blind randomized controlled trials.

Combination therapy with antidepressants and sleep medications is a promising candidate treatment for major depressive disorder (MDD) with insomnia. This systematic review and meta-analysis examined the efficacy and safety of combination therapy with antidepressants and sleep medication for treating MDD with insomnia compared to antidepressant monotherapy by sleep medication class (benzodiazepine, Z-drug, melatonin receptor agonist, and orexin receptor antagonist). This study was preregistered with PROSPERO (CRD42025636571). PubMed, CENTRAL, and Embase were searched for double-blind randomized controlled trials published until June 2024, resulting in eight eligible studies (1945 participants; eszopiclone = 4, zolpidem = 2, triazolam = 1, ramelteon = 1). Meta-analyses were performed based on six trials of Z-drugs. Compared with antidepressant monotherapy, combination therapy with antidepressants and Z-drugs resulted in higher remission rates from depressive symptoms (risk ratio: 1.25, 95% confidence interval [CI]: 1.08-1.45, P = 0.003), greater improvement in depressive symptoms (standardized mean difference [SMD]: 0.17, 95% CI: 0.01-0.33, P = 0.04) and insomnia symptoms (SMD: 0.43, 95% CI: 0.28-0.59, P < 0.001) in the short-term (within 12 weeks), with no difference in safety outcomes except for dizziness. Combination therapy with antidepressants and Z-drugs may be more useful for MDD with insomnia symptoms than antidepressant monotherapy in the short term. However, this study did not evaluate the benefits and harms of long-term adjunctive Z-drug therapy. Further long-term studies are needed to draw definitive conclusions regarding the efficacy and safety of combination therapy with antidepressants and Z-drugs. Moreover, further research is warranted to assess whether the findings of this study are applicable to other sleep medication classes.