Fifteen-year follow-up and impact of age and sex on cardiovascular outcomes in diabetes and non-diabetes patients without CAD

Abstract

Abstract Background In the absence of angiographically-detectable coronary artery disease (CAD), patients with diabetes have a risk of myocardial infarction that is comparable to patients without diabetes, while still having higher risks of ischemic stroke and all-cause mortality when followed for up to 10 years. In the current study we extended follow-up to 15 years and, additionally, examined the impact of age and sex on cardiovascular risk in diabetes and non-diabetes patients without CAD. Purpose To examine the cardiovascular risk and mortality associated with age and sex in diabetes and non-diabetes patients without CAD. Methods We included every patient with no or mild CAD when examined by coronary angiography in Western Denmark from 2003-2021 with and without diabetes. We performed age-stratified (<65 year, 65-74 years, and ≥75 years) and sex-stratified analyses. Patients were followed for up to 15 years. Outcomes were myocardial infarction, ischemic stroke, and all-cause death. We estimated adjusted hazard ratios (aHR) using Cox regression. Results We included 60,712 patients without angiographically detectable CAD, of whom 7,690 (12.6%) had diabetes. Median age was 62 years and 51% were men. Median follow-up was 9 years ((inter-quartile range 6-13)). Diabetes was associated with an increased 15-year risk of myocardial infarction (5.8% versus 4.1% aHR 1.30, 95% CI 1.13-1.50), ischemic stroke (8.1% vs 4.0%, aHR 1.87, 95% CI 1.66-2.10), and all-cause death (46.2% vs 33.1%, aHR 1.66, 95% CI 1.58-1.73) compared to patients without diabetes. The relative risk associated with diabetes declined by age (Figure 1), while there was no sex-dependent difference associated with diabetes (Figure 2). Conclusions At 15-year follow-up, diabetes patients without angiographically-detectable CAD at baseline had a relatively small increased risk of myocardial infarction but a substantial increased risk of ischemic stroke and all-cause mortality. Furthermore, the relative importance of diabetes decreased with age, while being independent of sex. These results support that aggressive multifactorial cardiovascular risk management, even in the absence of CAD and independently of age and sex, should be initiated when diabetes is diagnosed.Figure 1Figure 2