Caffeic acid for the management of leukopenia: a systematic review and meta-analysis

Many randomized controlled trials (RCTs) have revealed the benefits of caffeic acid tablets on leukopenia and thrombocytopenia, but the results are inconclusive. This meta-analysis of RCTs aimed to assess the effects of caffeic acid tablet supplementation on treating leukopenia.

A systematic review of PubMed, Scopus, Embase, Cochrane library, China Knowledge Network, China Biomedical Literature Database, Wipu.com and Wanfang Data were conducted, and the search time frame was from the establishment of the database up to May 2025. Data were pooled using a random-effects model to calculate standardized mean differences (SMDs) and 95% confidence intervals (CIs).

Thirty-three studies with 2,483 patients were included. Meta-analysis results indicated that the clinical effectiveness of caffeic acid tablets for leukopenia was significantly different from that of the control group (RR: 1.44; 95% CI: 1.31, 1.58, p < 0.01; I² = 67.0%, p < 0.01), and significantly increased white blood cell count (SMD: 1.39, 95% CI: 1.09, 1.70, p < 0.001; I² = 85.4%, p < 0.001), platelet count (SMD: 1.18, 95% CI: 0.46, 1.89, p < 0.001; I² = 94.4%, p < 0.001), and neutrophil count (SMD:0.88, 95% CI: 0.60, 1.16, p < 0.001; I² = 49.0%, p = 0.081). Caffeic acid tablets can reduce bone marrow suppression (RR: 0.34; 95% CI: 0.22, 0.54, p < 0.001; I² = 0.0%, p = 0.685), incidence of infection (RR: 0.50; 95% CI: 0.38, 0.64, p < 0.001; I² = 0.0%, p = 0.833) was significantly lower than that of the control group.

Caffeic acid may be a promising management for the treatment of leukopenia. The findings should be interpreted with caution due to the high risk of bias in many included trials and the limited generalizability, as all studies were conducted in China.