CARDIOVASCULAR disease (CVD) remains the leading global cause of death and disability, with individuals living with diabetes facing an elevated risk. While numerous studies have explored cardiovascular outcomes in people with diabetes, few have directly compared the risk between Type 1 diabetes (T1D) and Type 2 diabetes (T2D), particularly when factoring in sex differences. This study addresses that gap by analysing sex-specific cardiovascular risk in people with T1D and T2D using national data from Sweden. A key finding was that women with T1D had significantly higher cardiovascular risks than women with T2D across all age groups.
This longitudinal cohort study used data from the Swedish National Diabetes Register, including 404,026 individuals aged 18 to 84 years with T1D (n=38,351) or T2D (n=365,675), followed from 2016 to 2020. Cox proportional hazards models were used to assess time to first event for myocardial infarction (MI), heart failure (HF), stroke, cardiovascular mortality, and all-cause mortality. Analyses were stratified by age (<50, 50–59, 60–69, ≥70 years) and performed separately for males and females, adjusting for diabetes type and other established risk factors.
Among males under 50 years, those with T2D had significantly higher risks for all CVD (HR: 1.51; 95% CI 1.26–1.80), MI (HR: 2.40; 95% CI: 1.78–3.26), and HF (HR: 2.16; 95% CI: 1.40–3.35) compared to those with T1D. In contrast, older males with T2D (>70 years) had lower MI risk than those with T1D (HR: 0.74; 95% CI: 0.61–0.88). Women with T2D consistently had lower risk of all cardiovascular outcomes and mortality than women with T1D, particularly between ages 50–69. For example, in women aged 50–59, the HRs were 0.75 (95% CI: 0.64–0.79) for all CVD and 0.59 (95% CI: 0.46–0.74) for MI. Overall, female sex was protective in both diabetes types, with HRs of 0.78 in T1D and 0.65 in T2D.
These findings emphasise the importance of differentiating cardiovascular risk by both diabetes type and sex. Clinically, this means that women with T1D may need more intensive cardiovascular monitoring and risk reduction strategies. However, study limitations include the observational design and potential residual confounding, despite adjustment for multiple risk and socioeconomic factors. Nonetheless, the results support more individualised CVD risk assessment in diabetes care.
Reference
Patsoukaki V et al. Sex differences in risk for cardiovascular disease and all-cause mortality: a direct comparison of type 1 with type 2 diabetes patients in a nationwide register-based study. Abstract 47. EASD 2025, 15-19 September, 2025.
