Clinical efficacy and safety of compound Congrong Yizhi Capsules on Alzheimer's disease in mainland China: A systematic review with trial sequential analysis and GRADE assessment.

Abstract

Alzheimer's disease (AD) is a degenerative disease of the central nervous system (CNS) with insidious onset. AD is also the most common cause of dementia. Compound Congrong Yizhi Capsules (CCYC), a traditional Chinese medicine compound developed by the team of Beijing University of Chinese Medicine, has been widely used to treat AD. To systematically evaluate the clinical efficacy and safety of CCYC for AD by meta-analysis, Trial Sequential Analysis (TSA) and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. This study was registered at PROSPERO (CRD42022295496). Randomized controlled trials (RCTs) of CCYC as the treatment for AD published before December 1, 2021 were retrieved from 4 Chinses databases, 4 English databases and 2 clinical trials registration systems. RevMan 5.4 and STATA 17.0 was used to conduct the meta-analysis of the included studies, the quality of outcomes was rated by the GRADE system, the TSA was conducted by TSA 0.9.5.10 software. Seven studies were included, and the total sample size was 746. Meta-analysis showed that 6 months of treatment with CCYC plus conventional western medicine treatments (CTs) improved MMSE scores compared with CTs alone (WMD: 4.32, 95% CI: 3.23, 5.42), and TSA confirmed that more trials in the future will not reverse the result. Among which, CCYC combined with donepezil can significantly improve MMSE scores (WMD: 3.54, 95% CI: 2.86, 4.22). CCYC combined with olanzapine also showed good effect on both MMSE (WMD: 6.49, 95% CI: 5.54, 7.44) and ADL scores (WMD: 5.23, 95% CI: 4.63, 5.83). No serious adverse events were reported. The strengths of the evidences above are MODERATE. CCYC combined with cognition-modifying western medicine can improve cognitive function, mental behavioural symptoms, and activities of daily living in AD patients with good safety.