Associations of prediabetes with all-cause and cardiovascular mortality: A meta-analysis

BACKGROUND: Reports on the association of prediabetes with all-cause mortality and cardiovascular mortality are inconsistent. Objective. To evaluate the risk of all-cause and cardiovascular mortality in association with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). METHODS: Prospective cohort studies with data on prediabetes and mortality were included. The relative risks (RRs) of all-cause and cardiovascular mortality were calculated and reported with 95% confidence intervals (95% CIs). RESULTS: Twenty-six studies were included. The risks of all-cause and cardiovascular mortality were increased in participants with prediabetes defined as IFG of 110-125 mg/dL (IFG 110) (RR 1.12, 95% CI 1.05-1.20; and RR 1.19, 95% CI 1.05-1.35, respectively), IGT (RR 1.33, 95% CI 1.24-1.42; RR 1.23, 95% CI 1.11-1.36, respectively), or combined IFG 110 and/or IGT (RR 1.21, 95% CI 1.11-1.32; RR 1.21, 95% CI 1.07-1.36, respectively), but not when IFG was defined as 100-125 mg/dL (RR 1.07, 95% CI 0.92-1.26; and RR 1.16, 95% CI 0.94-1.42, respectively). CONCLUSIONS: Prediabetes, defined as IFG 110, IGT, or combined IFG 110 and/or IGT, was associated with increased all-cause and cardiovascular mortality.