Sudden Cardiac Death as First Manifestation of Cardiovascular Disease: A Nationwide Study of 54,028 Deaths.

BACKGROUND

Sudden cardiac death (SCD) is a significant public health problem. Knowledge on SCD victims without a history of cardiovascular disease (CVD) is limited, presenting challenges for future prevention efforts.

OBJECTIVES

This study aims to examine the differences between SCD cases with and without a known history of CVD.

METHODS

All Danish citizens were followed from January 1, 2010, until death or the end of the year. All deaths in Denmark during this period were reviewed by ≥1 medical doctor to identify cases of SCD. Data were analyzed from March 2023 until March 2024.

RESULTS

A total of 6,851 SCD cases were identified, of which 3,046 (44.5%) had no history of CVD. Incidence rates of SCD increased with age and were higher in cases with a history of CVD across all age groups. The difference in SCD incidence between individuals with and without a history of CVD decreased with age, with incidence rate ratios ranging from 21.6 (95% CI: 5.2-66.7) in those aged 0 to 19 years to 1.8 (95% CI: 1.7-1.9) in those aged >90 years. Female sex and living alone were associated with a lower odds of having a CVD before SCD with ORs of 0.66 and 0.75, respectively.

CONCLUSIONS

The distribution of SCD cases is nearly equal between individuals with and without a history of CVD, although the risk remains higher in those with prior CVD. Future research should aim to uncover the distinct causes and mechanisms driving SCD in populations with a known CVD, as well as the general population.