Abstract
BACKGROUND: Hyperglycaemia and dyslipidaemia are well-known risk factors for coronary artery disease (CAD) in type 1 diabetes. The impact of long-term cumulative exposure to these risk factors is less explored. We investigated the relationship between cumulative glycaemic and lipid exposure and CAD in individuals with type 1 diabetes. METHODS: This longitudinal study included 3495 adults with type 1 diabetes from the FinnDiane cohort, without end-stage kidney disease and no history of CAD or stroke at the study baseline. Total cumulative glycaemic exposure (CGE(tot)) and cumulative hyperglycaemic exposure (CGE(hg)), accounting only for time spent above an HbA(1c) of 53 mmol/mol (7%), were calculated from diabetes diagnosis. RESULTS: During a median follow-up of 19.38 years, 534 participants had their first-ever CAD event. CGE(hg) (odds ratio 1.03 [95% CI 1.02-1.05], p < 0.001) and cumulative exposure to LDL cholesterol, triglycerides, and non-HDL cholesterol all significantly increased the odds for incident CAD. The highest tertile of CGE(hg) associated with a twofold odds increase for incident CAD. CGE(tot) was not significantly associated with CAD after adjusting for cumulative lipid exposure. CONCLUSIONS: Both hyperglycaemia and dyslipidaemia are independently associated with CAD in type 1 diabetes. These findings emphasize the importance of reaching an HbA(1c) below 53 mmol/mol (7%) and minimizing lipid exposure, as well as calling on health care professionals to not settle for suboptimal care, but to continue their support and encouragement towards better management of diabetes.