Cognitive Improvement during Treatment for Mild Alzheimer's Disease with a Chinese Herbal Formula: A Randomized Controlled Trial

To explore the efficacy of Chinese herbal formula compared with donepezil 5 mg/day in patients with mild Alzheimer's disease (AD). Patients with mild AD meeting the criteria were randomized into Chinese herbal formula Yishen Huazhuo decoction (YHD) group and donepezil hydrochloride (DH) group during the 24-week trial. The outcomes were measured by ADAS-cog, MMSE, ADL, and NPI with linear mixed-effect models. 144 patients were randomized. The mean scores of ADAS-cog and MMSE in both YHD group and DH group both improved at the end of the 24-week treatment period. The results also revealed that YHD was better at improving the mean scores of ADAS-cog and MMSE than DH. Linear mixed-effect models with repeated measures showed statistical significance in time × group interaction effect of ADAS-cog and also in time × group interaction effect of MMSE. The data showed YHD was superior to DH in improving the scores and long term efficacy. Our study suggests that Chinese herbal formula YHD is beneficial and effective for cognitive improvement in patients with mild AD and the mechanism might be through reducing amyloid-β (Aβ) plaque deposition in the hippocampus. Chinese Clinical Trial Registry ChiCTR-TRC-12002846.