A target HbA1c between 7 to 7.7% reduces macrovascular events in T2D regardless of duration of diabetes: a meta-analysis of randomized controlled trials

Abstract

Introduction: The target glycosylated haemoglobin (HbA1c) at which macrovascular benefits may be derived in type 2 diabetes (T2D) has never been clearly outlined. This meta-analysis was conducted on fifteen randomized controlled trials to highlight the association of HbA1c range with macrovascular events. Methods: The association of different HbA1c clusters (intention to treat (ITT) and end-of-study [EOS]) range ( less or equal than 6.5%, 6.6% to 7.0%, 7.1% to 7.7%) with macrovascular complications and also the combined effect of duration of T2D (< 10 years or >= 10 years) and HbA1c levels was assessed. Results: Intensive glucose-lowering strategy resulted in a significant 13% reduction in non-fatal myocardial infarction (NFMI) (P=0.006). Based on HbA1c achieved, a significant 36% reduction in non-fatal stroke (P=0.008) and a 22% reduction in all-cause mortality (P=0.02) were observed in the group with HbA1c between 7.1% to 7.7% irrespective of diabetes duration. In the cohort, with diabetes duration <10 years, reduction of HbA1c in the range7.1% to 7.7% resulted in a significant 36% reduction in non-fatal stroke (NFS) (P<0.001). Conclusion: This is probably the first meta-analysis highlighting the importance of treating patients with T2D to a target HbA1C of 7 to 7.7%, as this target is associated with reduction in macrovascular events