[Sudden Cardiac Death: Trend Analysis by Sex and Age, Chile 2010 to 2020]

Sudden cardiac death (SCD) is a rare and unexpected event that occurs in apparently healthy individuals. In Chile, only one report has evaluated its incidence, published ten years ago.

To describe the incidence and etiology of SCD in Chile according to age, sex, and region, and to analyze its trend between 2010 and 2020.

Descriptive ecological study using data from the Department of Health Statistics and Information. Mortality rates per 100,000 inhabitants and proportional mortality (% of total annual deaths) were calculated. Trends were assessed using Prais-Winsten regression (PW) with 95% confidence intervals (95% CI).

A total of 1,115,620 deaths were recorded, of which 12,481 (1.12%) were attributed to SCD. The main causes were dilated cardiomyopathy (CMP) (37.15%), aortic dissection (17.24%), and complete atrioventricular block (9.63%). In individuals under 35 years of age, the most frequent etiologies were: dilated CMP (33.17%), hypertrophic CMP (16.17%), and aortic dissection (11.33%). Dilated CMP was the leading cause across both sexes and age groups. A decreasing trend was observed in both proportional mortality (PW: -0.038, 95% CI: -0.052; -0.025) and mortality rates in the total population (PW: -0.199, 95% CI: -0.261; -0.138). However, no significant decrease was observed in mortality rates in individuals under 35 years (PW: 0.003, 95% CI: -0.028; 0.034). The Valparaíso region recorded the highest rate (8.16/100,000), while Aysén had the lowest (2.80/100,000).

SCD is infrequent in Chile. Its main causes are dilated cardiomyopathy and aortic dissection. While a decreasing trend is observed in the general population over the past decade, no such trend is seen in individuals under 35, highlighting the need for targeted prevention strategies.