Efficacy of Yukmijihwang-tang on symptoms of Alzheimer disease: A protocol for systematic review and meta-analysis

BACKGROUND: Alzheimer disease (AD) is the most common cause of dementia, which may lead to severe memory loss and other cognitive disorders. Yukmijihwang-tang (YMJ), a type of Korean traditional herbal medicine, has been shown to be effective against neurodegenerative diseases. Although a meta-analysis on the efficacy of YMJ on AD exists, the study had some limitations, and there have been several newly published studies assessing the effect of YMJ. Therefore, the purpose of this study is to evaluate the efficacy and safety of YMJ as a treatment for AD through a meta-analysis. METHODS: A systematic search of the following electronic databases will be conducted to identify eligible studies: MEDLINE (PubMed), Elsevier (EMBASE), The Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Korean Medical Database (KMBASE), Oriental Medicine Advanced Searching Integrated System (OASIS), Korean Traditional Knowledge Portal, Citation Information by NII (CiNii), China National Knowledge Infrastructure (CNKI). All randomized controlled trials assessing the efficacy and safety of YMJ on the symptoms of AD will be included. Two independent reviewers will perform article retrieval, deduplication, data screening, data extraction, quality evaluation, and data analyses using RevMan version 5.4. The Cochrane risk of bias tool will be used to assess the quality of the trials. RESULTS: This study will provide synthesis of the cognitive function measured with neuropsychological tests, behavioral and psychological symptoms of dementia (BPSD), and activities of daily living (ADL) measured using validated scales. The clinical effective rate and adverse events will also be analyzed to assess the efficacy and safety of YMJ for treating AD. CONCLUSION: This systematic review will provide evidence for the efficacy and safety of YMJ in AD. ETHICS AND DISSEMINATION: Ethical approval is not required because individual patient data will not be included in this study. The study findings will be disseminated through conference presentations.