Effects of intensive glycaemic control on ischaemic heart disease: analysis of data from the randomised, controlled ACCORD trial

Background Hyperglycaemia could substantially increase the risk of ischaemic heart disease in patients with type 2 diabetes. We investigated whether intensive lowering of glucose concentrations affects risk. Methods We assessed 10 251 adults aged 40-79 years with established type 2 diabetes, mean glycated haemoglobin A(1c) (HbA(1c)) concentration of 67 mmol/mol (8.3%), and risk factors for ischaemic heart disease enrolled in the ACCORD trial. Participants were assigned to intensive or standard therapy (target HbA(1c) less than 42 or 53-63 mmol/mol [less than 6.0% or 7.0-7.9%], respectively). We assessed fatal or non-fatal myocardial infarction, coronary revascularisation, unstable angina, and new angina during active treatment (mean 3.7 years) plus a further mean 1.2 years. This trial is registered with ClinicalTrials.gov, number NCT00000620. Findings Myocardial infarction was less frequent in the intensive than in the standard therapy group during active treatment (hazard ratio [HR] 0.80, 95% CI 0.67-0.96; p=0.015) and overall (0.84, 0.72-0.97; p=0.02). Findings were similar for combined myocardial infarction, coronary revascularisation, and unstable angina (active treatment HR 0.89, 95% CI 0.79-0.99, overall 0.87 0.79-0.96) and for coronary revascularisation alone (0.84, 0.75-0.94) and unstable angina alone (0.81, 0.67-0.97) during full follow-up. With lowest achieved HbA(1c) concentrations included as a time-dependent covariate, all hazards became non-significant. Interpretation Raised glucose concentration is a modifiable risk factor for ischaemic heart disease in middle-aged people with type 2 diabetes and other cardiovascular risk factors.