The effectiveness and safety of Jihwang-eumja (Dihuang Yizi) compared to Western medications in patients with Alzheimer's disease: A systematic review and meta-analysis.

Background And Purpose: Jihwang-eumja is reported to be effective in decreasing β-amyloid expression and activating monoamine oxidase and acetylcholinesterase in rat models. This systematic review aims to evaluate the effectiveness of Jihwang-eumja in Alzheimer's disease compared to Western medications.

Methods: We searched Medline, Embase, CENTRAL, CINAHL, CNKI, ScienceON, KISS, and Kmbase. Randomized controlled trials comparing the effectiveness of Jihwang-eumja and Western medications on the cognition and the activities of daily living in Alzheimer's disease were included. The results were synthesized using meta-analysis. The risk of bias was evaluated using the Cochrane risk-of-bias tool, and the evidence level of each outcome was suggested using the GRADE system.

Results: A total of 165 studies were screened, and six were included in the systematic review and meta-analysis. A total of 245 and 240 participants were included in the intervention and comparison groups, respectively. The results showed that Mini-Mental State Examination was 3.19 (95%CI: 1.68-4.70) higher, and the standardized mean difference of activities of daily living was 1.13 (95%CI: 0.89-1.37) higher in the Jihwang-eumja group than in Western medications group. The included studies contained some concerns of the risk of bias, and the certainty of the evidence was considered moderate.

Conclusion: Despite the small number of studies and high heterogeneity, we could verify the applicability of Jihwang-eumja for Alzheimer's disease.