People with diabetes continue to face a high burden of cardiovascular disease despite modern care. A study in The Lancet Diabetes & Endocrinology analyzed data from the Swedish National Diabetes Register, linking records for 404,026 adults with type 1 or type 2 diabetes to national health databases. Participants aged 18–84 years were followed from 2016 to 2020, with comparisons also made to matched controls without diabetes.
Among adults younger than 50 years, type 2 diabetes carried a 23% higher risk of cardiovascular disease than type 1 (HR 1.23, 95% CI 1.07–1.41). However, in those older than 60 years, type 2 diabetes showed a 13% lower risk compared with type 1 (HR 0.87, 95% CI 0.82–0.92). Similar trends were seen for myocardial infarction (HR 0.67, 95% CI 0.61–0.73) and all-cause mortality (HR 0.89, 95% CI 0.84–0.95) in the older age group. Stroke risk was overall lower in type 2 diabetes (HR 0.91, 95% CI 0.84–0.98).
For heart failure, type 2 diabetes carried a higher risk than type 1 at younger ages (HR 1.60, 95% CI 1.15–2.21). Among people with pre-existing cardiovascular disease, those with type 2 diabetes had consistently lower risks than those with type 1 for all cardiovascular events (HR 0.76, 95% CI 0.70–0.81), myocardial infarction (HR 0.62, 95% CI 0.56–0.70), cardiovascular mortality (HR 0.68, 95% CI 0.61–0.75), and all-cause mortality (HR 0.71, 95% CI 0.66–0.77).
After adjustment for multiple risk factors, type 2 diabetes showed higher overall risk of incident cardiovascular disease and mortality compared with type 1. However, when diabetes duration was excluded, type 1 diabetes carried the greater risk. Compared with matched controls without diabetes, both groups had higher cardiovascular and mortality risk, but the excess was most pronounced for type 1 diabetes.
These findings suggest that longer diabetes duration in type 1 diabetes largely explains its higher cardiovascular and mortality risk. The results reinforce the need for early and aggressive management of modifiable risk factors in both type 1 and type 2 diabetes.
