Diabetes and sudden cardiac death in a nationwide, unselected population

Abstract Background and purpose Sudden cardiac death (SCD) remains a prominent cause of mortality, with individuals afflicted by diabetes mellitus (DM) bearing a heightened risk of ventricular arrhythmias and SCD. However, comprehensive investigations in a nationwide, unselected context are lacking. Therefore, this study aimed to compare the incidence rates (IR) of SCD among individuals with Type 1 Diabetes Mellitus (T1DM) and Type 2 Diabetes Mellitus (T2DM) to the general population. Methods The study included the entire Danish population (approximately 5.5 million individuals) in 2010. SCD cases were identified through the detailed Danish death certificates and discharge summaries, yielding 6851 cases of SCD. The Danish Register of Medicinal Product Statistics, containing comprehensive prescription data from Danish pharmacies, facilitated the identification of individuals with T1DM and T2DM. Loss of life years was estimated for both T1DM and T2DM patients. Results Among the identified 6851 SCD cases, 272 (4%) were diagnosed with T1DM, and 833 (12%) with T2DM. Incidence rates of SCD were consistently elevated across all age groups for individuals with diabetes, compared to the general population (Figure 1). Patients with T1DM exhibited higher incidence rates than patients with T2DM (Figure 1). Notably, individuals aged 30-40 years with DM showed the greatest differences in incidence rates of SCD compared to the general population, with incidence rate ratios of 20.0 (95% confidence interval: 11.8-80.0) and 5.6 (95% confidence interval: 2.7-14.0) for T1DM and T2DM, respectively. On average, each 30-year-old patient with either T1DM or T2DM experiences a reduction of 3.7 and 3 life-years, respectively, due to the increased risk of SCD in these groups (Figure 2). Conclusion This nationwide study examines the incidence rates of SCD among individuals with and without a history of DM across all age brackets. Notably, patients with DM display consistently elevated incidence rates across age groups, with a particularly pronounced risk observed in those with T1DM. For both T1DM and T2DM, SCD is an important contributing factor to their shorter life expectancy compared to the general population. The heightened risk among individuals with DM underscores the importance of improved risk stratification for these patients.Incidence rates of SCDStacked cumulative incidence curves