Efficacy and safety of suanzaoren decoction for chronic insomnia disorder in adults: study protocol for randomised, double-blind, double-dummy, placebo-controlled trial

BACKGROUND Insomnia disorder is defined as a combination of dissatisfaction with sleep quantity or quality and a significant negative impact on daytime functioning. Chronic insomnia disorder refers to clinical symptoms of persistent insomnia at least three nights a week for at least 3 months. Prevalence estimates of insomnia disorder range from 12% to 20% in the adult population, with approximately 50% having a chronic course. The potential side effects of hypnotic medications hinder their clinical application. Thus, traditional Chinese medicine is considered as an alternative option for treating insomnia. OBJECTIVE To evaluate the efficacy and safety of suanzaoren decoction (SZRD), a classic Chinese herbal prescription, for adult chronic insomnia disorder. METHODS/ANALYSIS This is a randomised, double-blind, double-dummy, placebo-controlled clinical trial. A total of 150 patients with chronic insomnia disorder are randomised, allocated in a ratio of 1:1:1 to three groups: intervention group, control group and placebo group. The intervention group receives SZRD granule plus zolpidem tartrate (ZT) placebo; the control group receives ZT tablet plus SZRD granule placebo; and the placebo group receives ZT placebo and SZRD granule placebo. The patients receive medicine or placebo for 5 weeks and are followed up at 20 weeks. The primary outcome measures are polysomnography and Pittsburgh Sleep Quality Index. Secondary outcome measures are the Insomnia Severity Index, sleep diary and safety assessment. Outcomes will be assessed at baseline and after treatment. TRIAL REGISTRATION NUMBER ChiCTR-IOR-16009198. pre-results.