Decline in incidence of sudden cardiac death in the young: a 10-year nationwide study of 8756 deaths in Denmark

AIMS: Sudden cardiac death in the young (SCDY) accounts for a significant proportion of deaths among the young. The aim of this nationwide study was to examine temporal changes in incidence and causes of SCDY in Denmark in 2000-2009. During this 10-year period, several public and private health initiatives were undertaken to decrease morbidity and mortality in Denmark.

METHODS AND RESULTS: All deaths among persons aged 1-35 years in Denmark in 2000-2009 (23.7 million person-years) were included. Death certificates, autopsy reports, discharge summaries, and data from nationwide administrative registries were used to identify SCDY cases. Sudden cardiac death in the young incidence rates were age-adjusted and sex-adjusted using direct standardization. Temporal changes in standardized SCDY incidence rates were reported as average annual percent changes. In the 10-year study period, there were 8756 deaths, of which we identified 635 (7%) SCDY cases. For these SCDY cases, median age at death was 29 years and 68% were men. Standardized incidence of SCDY decreased from 3.1 per 100 000 person-years in 2000 [95% confidence interval (CI) 2.4-3.8] to 2.5 per 100 000 person-years in 2009 (95% CI 1.9-3.2). This corresponds to an average annual percent change of -3.0% (95% CI -5.8 to -0.1). The distribution of major causes of SCDY did not change significantly throughout the study period.

CONCLUSION: Incidence of SCDY decreased significantly from 2000 through 2009 in Denmark with an average annual percent change of -3%. Further research is needed to elucidate underlying causes of this development.