Abstract Background The evidence on whether long-term cardiovascular disease (CVD) outcomes differ among males and females with incident diabetes remains equivocal. Objective To examine sex-differences in the association between incident diabetes and 5-year risk of CVD and mortality at the population-level. Methods The study population consisted of an inception cohort of individuals between 40 and 80 years without diabetes or CVD on April 1, 2013 in the province of Alberta, Canada (N=1,315,885). Incident diabetes during a 3-year period was used to categorize males and females by diabetes status as of March 31, 2016. Primary outcome of interest was a combination of CVD hospitalization (defined as a hospitalization with a primary diagnosis of heart failure, acute coronary syndromes, cerebrovascular disorders, atrial fibrillation and flutter, ventricular arrhythmia, or sudden cardiac death) or all-cause mortality over a 5-year period until March 31, 2021. Inverse probability of treatment weighting (IPTW) was used to reduce the impact of confounders between individuals with and without diabetes. Kaplan-Meier curves were used to examine unadjusted outcomes and Cox-proportional hazards models were used to examine the impact of diabetes on outcomes in males and females after adjusting for the following: age, hypertension, material deprivation, urban/rural residence, and comorbidity burden. Results Among 672,881 females and 643,004 males, 27,082 (4.0%) and 33,054 (5.1%) developed incident diabetes, respectively. Regardless of sex, individuals with diabetes were older and had higher rates of hypertension and other comorbidities. Overall, CVD hospitalization/mortality rates per 1000 person years were 7.5% (95% confidence interval (CI): 7.4–7.6) among females compared to 11.7% (95% CI: 11.6–11.8) among males. When stratified by diabetes status, the rates of the combined endpoint were 7.2% (95% CI: 7.1–7.3) among females with no diabetes (F w/o DM), 11.2% (95% CI: 11.1–11.3) among males with no diabetes (M w/o DM), 14.7% (95% CI: 14.0–15.3) among females with diabetes (F with DM) and 20.9% (95% CI: 20.1–21.6) among males with diabetes (M with DM, Figure 1). The adjusted hazard ratio (aHR) associated with diabetes on outcomes was similar among males (aHR 1.38 95% confidence interval (CI): 1.36–1.41) and females (aHR 1.39 95% CI: 1.36–1.42). Conclusions The presence of diabetes weakens the possible cardio-protection of female sex with respect to CVD outcomes. Future work aims to assess CVD prevention, management and treatment among males with females with incident diabetes. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Canadian Institutes of Health Research (CIHR) Sex and Gender Science Chair
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