[Effect of reactions to symptoms onset on early mortality from myocardial infarction]

A patient's social circumstances at the time when acute myocardial infarction (AMI) symptoms first appear might influence survival. Our objectives were to study the living conditions, the location where symptoms started, the type of symptoms, and the delay before action was taken in patients with AMI who survived more than one hour, and to analyze the relationship between these variables and mortality in different time periods.

Population-based observational cohort study carried out in 1997-1998. Main data source: Registre Gironí del Cor (REGICOR). Death certificates provided information on patients who died before they could be included in the register. The patients' demographic characteristics, lifestyle, clinical history, electrocardiographic abnormalities, cardiac enzyme levels, treatment, and diagnosis were recorded. Mortality before and during hospitalization, and overall mortality at 28 days were studied.

Of the 1,097 patients included, 274 (24.97%) died before reaching hospital, 171 (15.58%) died in hospital, and 652 (59.4%) were alive at 28 days. Mortality was lower in patients who went directly to hospital (OR = 0.32, 95% CI, 0.17-0.59). Mortality at 28 days was higher in those with atypical symptoms (OR = 5.52, 95% CI, 2.90-10.50), and in those who lived in an institution (OR = 9.47, 95% CI, 1.05-84.9).

In the absence of specially equipped ambulances, AMI patients who went directly to the hospital or who had typical symptoms had a better chance of survival both before hospitalization and at 28 days. In contrast, 28-day mortality was higher in institutionalized patients.