OBJECTIVE: This study aims to systematically evaluate the therapeutic effects of Decoction of Dihuang Yinzi on Alzheimer's disease and provide evidence-based medical evidence for the clinical application of traditional Chinese medicine.
METHODS: A comprehensive search was conducted across multiple databases, including PubMed, Embase, Cochrane Library, CNKI, VIP, Wan Fang database, and SinoMed database, to collect clinical randomized controlled trials of Decoction of Dihuang Yinzi in the treatment of Alzheimer's disease. Strict literature screening was performed based on predefined inclusion and exclusion criteria. The quality of the included studies was assessed using the Cochrane Collaboration risk of bias assessment tool and the GRADE system recommendation level method. Data synthesis and processing were performed using Review Manager 5.4 and Stata 17 software, while the quality of evidence for outcome indicators (RR, SMD, and WMD) was evaluated using GRADE Profiler 3.6 software.
RESULTS: A total of 11 studies involving 798 patients met the inclusion criteria. Decoction of Dihuang Yinzi, whether used alone or in combination with conventional western medicine, demonstrated superior efficacy compared to conventional western medicine alone in improving the total clinical effective rate, TCM syndrome score, ADL score, MMSE, and HDS score in the treatment of Alzheimer's disease. Furthermore, it exhibited a favorable safety profile. However, the GRADE evidence quality rating for the included studies was determined to be low.
CONCLUSIONS: Decoction of Dihuang Yinzi, either used alone or in combination with conventional western medicine, shows promising results in enhancing cognitive and memory functions as well as the self-care ability of patients with Alzheimer's disease. However, the low GRADE evidence quality rating underscores the need for targeted improvements in the design and implementation of clinical randomized controlled trials during future research endeavors.