Effect of Yi-Gan San on psychiatric symptoms and sleep structure at patients with behavioral and psychological symptoms of dementia

OBJECTIVE: Recently, traditional herbal medicines have been reported to be effective for behavioral and psychological symptoms of dementia (BPSD). This study aims to examine the efficacy of Yi-Gan San (YGS) in the improvement of BPSD and sleep disorders in patients with dementia. METHODS: Five patients (1 male and 4 female) with dementia in accordance with DSM-IV criteria were investigated. Participants were treated with YGS for 4 weeks. The Nursing Home version of Neuropsychiatric Inventory (NPI-NH) for the assessment of BPSD, the Mini-Mental State Examination (MMSE) for cognitive function, polysomnography for evaluation of sleep structure, and the Pittsburgh Sleep Quality Index for subjective sleep quality were carried out at baseline and at the end of treatment. RESULTS: All patients completed the trial. Significant improvements in the total NPI-NH score (34.0+/-6.5 to 12.8+/-6.6) as well as delusions, hallucinations, agitation/aggression, anxiety, and irritability/lability, whereas MMSE scores were unchanged. PSG revealed increases in total sleep time, sleep efficiency, stage 2 sleep, and decreases in the number of arousals and periodic limb movements. Subjective sleep quality was also improved. No adverse effects were observed. CONCLUSION: YGS was effective for BPSD and sleep disturbances, and well tolerated in patients with dementia. Further examinations using a double-blind placebo-controlled design are necessary.