Yokukansan in the Treatment of Behavioral and Psychological Symptoms of Dementia: An Updated Meta-Analysis of Randomized Controlled Trials

Background: Previous clinical studies found that yokukansan has a therapeutic effect on behavioral and psychological symptoms of dementia (BPSD) in dementia patients. Objective: To perform an updated meta-analysis of randomized controlled trials (RCTs) testing yokukansan for patients with BPSD. Methods: Primary efficacy and safety endpoints were BPSD total scores and all-cause discontinuation, respectively. Secondary outcomes were BPSD subscales, cognitive function scores [Mini-mental state examination (MMSE)], activities of daily living (ADL) scores, discontinuation due to adverse events (AEs), and incidences of AEs. Results: Five RCTs with 381 patients with BPSD were included. Compared with controls [placebousual care (UC)], yokukansan significantly decreased BPSD total scores [standardized mean difference (SMD) = -0.32, 95 confidence interval (CI) = -0.53 to -0.11, p = 0.003, I² = 0, N = 5 studies, n = 361]. Yokukansan was more efficacious in reducing BPSD subscale scores (delusions: SMD = -0.51, 95 CI = -0.98 to -0.04, hallucinations: SMD = -0.54, 95 CI = -0.96 to -0.12, agitation/aggression: SMD = -0.37, 95 CI = -0.60 to -0.15) than placeboUC. However, yokukansan was not superior to placeboUC for BPSD total as well as any subscales scores only in Alzheimer's disease patients. Compared with UC, yokukansan treatment improved ADL scores (SMD = -0.32, 95 CI = -0.62 to -0.01). MMSE scores did not differ between the yokukansan and placeboUC treatment groups. No significant differences were found in all-cause discontinuation, discontinuation due to AEs, and incidences of AEs between yokukansan and placeboUC treatments. Conclusions: Our results suggest that yokukansan is beneficial for the treatment of patients with BPSD and is well-tolerated; it was not beneficial for BPSD total and any subscale scores only in Alzheimer's disease patients.