BACKGROUND: A large proportion of all deaths are sudden cardiac death (SCD). Reliable estimates of nationwide incidence of SCD, however, are missing.

OBJECTIVE: To estimate SCD burden across all ages in Denmark and compare this with other common causes of death.

METHODS: All deaths in Denmark (population of 5.5 million) in 2010 were manually reviewed case-by-case. Autopsy reports, death certificates, and information from nationwide health registries were systematically examined to identify all SCD in 2010. According to the level of detail of the available information, all deaths were categorized as either non-SCD, definite SCD, probable SCD, or possible SCD.

RESULTS: There were 54,028 deaths in Denmark in 2010, of which 6,867 (13%) were categorized as SCD (591 definite SCD, 1,568 probable SCD, and 4,708 possible SCD). Incidence rate of definite SCD was 11 (95%-CI: 10-12) per 100,000 person-years. Including definite, probable, and possible SCD cases, the highest possible overall SCD incidence rate was 124 (95%-CI: 121-127) per 100,000 person-years. Estimated SCD burden was larger than or similar to all other common causes of death. Of all SCD cases, 49% were not diagnosed with cardiovascular disease prior to death.

CONCLUSION: SCD accounted for up to 13% of all deaths. Almost half of all SCD occurred in persons without prior history of cardiovascular disease. Consequently, optimization of risk stratification and prevention of SCD in the general population should be given high priority.