Modified Xiaochaihu Decoction Combined with Mirtazapine in the Treatment of Persistent Depression: A Pilot Randomized Controlled Trial

Abstract

Background. Western drugs effectively manage persistent depressive disorder (PDD) but are associated with side effects. Objective. To observe the efficacy and safety of modified Xiaochaihu Decoction combined with mirtazapine in treating PDD. Methods. Patients with PDD were enrolled at the Naval General Hospital (06/2018–02/2019) and randomized to modified Xiaochaihu Decoction and modified Xiaochaihu Decoction with mirtazapine. The self-rating depression scale (SDS) and traditional Chinese medicine (TCM) scale were assessed at baseline and after 12 weeks. The overall clinical efficacy (primary outcome) and adverse reactions were observed. Results. Sixty-four participants completed the trial in the combined and control groups (30 and 28), respectively. In controls, the total effective rate was 78.6%, compared with 96.7% in the combined group ( $P=0.035$ ). The scores of the SDS and TCM syndrome scale in the two groups were lower after treatment ( $P<0.001$ ) but without difference between groups ( $P=0.077$ ). The combined group showed higher improvement rates regarding insomnia (96.4% vs. 44.0%, $P<0.001$ ), bitter taste (90.5% vs. 52.6%, $P=0.007$ ), languid (72.0% vs. 31.8%, $P=0.006$ ), and belching/anorexia (100% vs. 52.6%, $P<0.001$ ). The combined group showed a higher frequency of adverse events (73.3% vs. 3.6%) ( $P<0.001$ ). Conclusion. Modified Xiaochaihu Decoction combined with mirtazapine effectively treats PDD, and its curative effect is better than that of TCM alone. Trial Registration. This trial was registered with https://www.chictr.org.cn/index.aspx/ChiCTR2100048188.