Insufficient evidence to recommend Shu Mian Capsule in managing depression with or without comorbid insomnia : a systematic review with meta-analysis and trial sequential analysis

Abstract

Aim: This systematic review with trial sequential analysis (TSA) aims to evaluate the efficacy and safety of Shu Mian Capsule (SMC), a commercial Chinese polyherbal preparation, for managing depression with or without comorbid insomnia. Methods: Controlled clinical trials assessing SMC against waitlist control, placebo or active controls, or as an adjunct treatment were searched across seven databases. Risk of bias and evidence quality were assessed using Cochrane criteria and GRADE framework, respectively. Results: Fourteen studies were analyzed, involving 1207 participants. Trials comparing SMC with placebo or standard antidepressive treatments were limited. In depressed patients without comorbid insomnia, combining SMC with antidepressants reduced the incidence of antidepressants-induced sleep disorders (from 12.2% to 3.8%) but did not significantly lower Hamilton Rating Scale for Depression (HAM-D) scores compared to antidepressants alone [SMD = −0.09, 95% CI (−0.32, 0.14), p = 0.45]. In depressed patients with comorbid insomnia, the combination of SMC and psychotropic drugs significantly reduced HAM-D [SMD = −1.29, 95% CI (−1.96, −0.62), p < 0.01] and Pittsburgh Sleep Quality Index scores [SMD = −1.53, 95% CI (−1.95, −1.11), p < 0.01], and exhibited a lower incidence of various drug-related adverse effects compared to psychotropic drugs alone. TSA validated the sample size adequacy; nevertheless, the methodological quality of supporting studies varied from very low to low due to substantial bias risk. Additionally, 92.9% of trials lacked follow-ups. Conclusion: The effectiveness of SMC as an alternative to conventional antidepressive treatment is unclear. For depressed patients with comorbid insomnia, adding SMC to standard care demonstrates augmented efficacy and improved safety, though the supporting evidence is methodologically limited. Further rigorous trials are warranted to confirm SMC’s short-term efficacy and explore its medium-to long-term effects as either an alternative or complementary therapy. Current evidence precludes recommendations for the administration of SMC in depression.