Long-term effect of lifestyle interventions in the cardiovascular and all-cause mortality of subjects with prediabetes and type 2 diabetes: A systematic review and meta-analysis

Background: Lifestyle interventions improve the metabolic control of individuals with hyperglycemia. We aimed to determine the effect of lifestyle interventions on cardiovascular and all-cause mortality in this population.

Methods: Searches were made through MEDLINE, Cochrane CENTRAL, Embase, and Web of Science (no date/language restriction, until May 15, 2022). Were included randomized clinical trials (RCTs) of subjects with prediabetes and type 2 diabetes, comparing intensive lifestyle interventions to usual care, and a minimum of 2 years of active intervention. Data from the 11 RCTs selected were extracted in duplicate. A frequentist and arm-based meta-analysis was performed using random effects models to estimate relative risk (RR) for mortality, and heterogeneity was assessed through I2 metrics. A generalized linear mixed model (GLMM) was performed to confirm the findings.

Results: Lifestyle interventions were not superior to usual care in reducing cardiovascular (RR, 0.99; 95% CI, 0.79 to 1.23) and all-cause mortality (RR, 0.93; 95% CI, 0.85 to 1.03). Subgroup, sensitivity and meta-regression analyses showed no influence of type of intervention, mean follow-up, age, glycemic status, geographical location, risk of bias, and weight change. All these results were confirmed with the GLMM.  Most studies had a low risk of bias according to the RoB 2.0 tool, and the GRADE approach resulted in moderate certainty of evidence for both outcomes.

Conclusion: Intensive lifestyle interventions implemented so far did not show superiority to usual care in reducing cardiovascular and all-cause mortality in subjects with prediabetes and type 2 diabetes.