Evaluation of the effects of Bauhinia forficata as an adjuvant in the treatment of type 2 diabetes mellitus: Systematic review and meta-analysis

Introduction: Type 2 diabetes mellitus (T2DM) is characterized by defects in insulin action and secretion. Bauhinia forficata has been observed to exhibit an effect in diabetes treatment due to its hypoglycemic activity. This systematic review with meta-analysis aimed to assess the effects of using Bauhinia forficata as an adjuvant treatment for individuals with T2DM. Methods: We conducted a comprehensive search strategy using relevant keywords and their synonyms, focusing on "Bauhinia forficata" and "diabetes mellitus." The search encompassed online databases such as Medline, Embase via OVID, and the Cochrane Library, without imposing language restrictions. We included studies that evaluated individuals diagnosed with T2DM, who were administered Bauhinia forficata, compared to placebo or active control, and who presented glycemia and glycated hemoglobin as outcome measures. Studies not meeting these criteria, as well as literature reviews, animal or in vitro experiments, were excluded. The methodological quality of the included studies was assessed using the Risk of Bias 2 tool. The results were presented through tables and graphs, and forest plots were generated to illustrate the effects of interventions on various outcomes, using RevMan software 5.4. Results: Four studies met the inclusion criteria, comprising two randomized controlled trials (RCT) and two nonrandomized studies of interventions (NRSI). Compared to placebo, Bauhinia forficata significantly improved glycemia (SMD -0.60, 95 % CI -0.15 to -1.05, p = 0.009, 1 RCT, n = 111, low certainty evidence; SMD -0.64, 95 % CI -1.25 to -0.03, p = 0.04, I2=42 %, 2 NSRIs pre-test/post-test, n = 40, very low certainty evidence). However, only the RCT evidence demonstrated significant improvements in HbA1c (SMD -0.48, 95 % CI -0.93, p = 0.03, 1 RCT, n = 111, low certainty evidence; SMD -0.25, 95 %CI -0.69 to 0.19, p-0.27, I2=0 %, 2 NSRIs pretest/posttest, n = 40, very low certainty evidence). No differences were found between Bauhinia forficata and Imperata brasiliensis (glycemia SMD -0.03, 95 % CI -1.01 to 0.95, p = 0.96, 1 RCT, n = 16, very low certainty evidence; HbA1c SMD 0.06, 95 % CI -0.92 to 1.04, p = 0.96, 1 RCT, n = 16, very low certainty evidence). Conclusions: The findings suggest that Bauhinia forficata may be effective in reducing blood glucose levels; however, this evidence needs to be interpreted with caution. PROSPERO registration: CRD42022370143.