Incidencia y letalidad por infarto agudo del miocardio en Chile: 2001-2007 / Incidence and case fatality due to acute myocardial infarction in Chile in the period 2001-2007

ABSTRACT

Background: Acute myocardial infarction (AMI) causes 73.6 percent of coronary heart disease (CHD) deaths in Chile. Aim: To estimate the incidence and case fatality of AMI and analyze their trends between 2001-2007. Material and Methods: A time-series study analyzing all cases of AMI (according to the International Classification of Diseases (ICD)-10, I21 code), registered in the National Hospitalizations and Death databases. Annual incidence rates and case fatality by sex and age groups were calculated. The direct method was used to standardize rates by age, using the World Health Organization 2000 Population. Prais-Winsten regression models were used to evaluate trends, expressed as relative change. Results: Between 2001 and 2007, we estimated that 83,754 cases of AMI occurred. Standardized annual incidence rate was 74.4 per 100,000 inhabitants (98.0 in men and 51.0 in women). Incidence rates increased by 34 percent in individuals < 45 years of age and 9.2 percent in the group 55-64 years (p < 0.001, both). Total case fatality was 49.5 percent (45.4 percent in men and 57.2 percent in women; p < 0.001), and its trend analysis showed a significant annual reduction of 1.2 percent in men and 0.81 percent in women. In-hospital case fatality was 14.2 percent (11.3 and 20.4 percent in men and women, respectively; p < 0.001). There was a significant annual reduction of mortality (0.57 and 1.01 percent in men and women, respectively (p < 0.05). Conclusions: The incidence of AMI was stable in the whole population, but increased in younger age groups. Total and in-hospital case-fatality decreased. Despite the greater reduction of case fatality in women, they still have a higher risk of dying while in hospital.