Aims/Hypothesis: Only 51% of patients with type 2 diabetes achieve the hemoglobin A1c (HbA1c) <7% target. Mind and body practices have been increasingly used to improve glycemic control among patients with type 2 diabetes, but studies show inconsistent efficacy. The authors conducted a systematic review and meta-analysis to assess the association between mind and body practices, and mean change in HbA1c and fasting blood glucose (FBG) in patients with type 2 diabetes. Methods: The authors conducted a literature search of Ovid MEDLINE, Embase, and ClinicalTrials.gov seeking through June 10, 2022, published articles on mind and body practices and type 2 diabetes. Two reviewers independently appraised full text of articles. Only intervention studies were included. Reviewers extracted data for meta-analysis. Restricted maximum likelihood random-effects modeling was used to calculate the mean differences and summary effect sizes. The authors assessed heterogeneity using Cochran's Q and I2 statistics. Funnel plots were generated for each outcome to gauge publication bias. Weighted linear models were used to conduct study-level meta-regression analyses of practice frequency. Results: The authors identified 587 articles with 28 meeting the inclusion criteria. A statistically significant and clinically relevant mean reduction in HbA1c of -0.84% (95% confidence interval [CI]: -1.10% to -0.58%; p < 0.0001) was estimated. Reduction was observed in all intervention subgroups: mindfulness-based stress reduction: -0.48% (95% CI: -0.72% to -0.23%; p = 0.03), qigong: -0.66% (95% CI: -1.18% to -0.14%; p = 0.01), and yoga: -1.00% (95% CI: -1.38% to -0.63%; p < 0.0001). Meta-regression revealed that for every additional day of yoga practice per week, the raw mean HbA1c differed by -0.22% (95% CI: -0.44% to -0.003%; p = 0.046) over the study period. FBG significantly improved following mind and body practices, with overall mean difference of -22.81 mg/dL (95% CI: -33.07 to -12.55 mg/dL; p < 0.0001). However, no significant association was found between the frequency of weekly yoga practice and change in FBG over the study period. Conclusions/Interpretation: Mind and body practices are strongly associated with improvement in glycemic control in patients with type 2 diabetes. The overall mean reduction in HbA1c and FBG was clinically significant, suggesting that mind and body practices may be an effective, complementary nonpharmacological intervention for type 2 diabetes. Additional analyses revealed that the mean decrease in HbA1c was greater in studies requiring larger number of yoga practice sessions each week.
Keywords: clinical practice; complementary medicine; epidemiology; mind and body practices; type 2 diabetes.