Socioeconomic Status and Risk of Acute Myocardial Infarction. Population-Based Case-Control Study

Introduction and objectivesSocioeconomic status is associated with cardiovascular mortality. The aims of this study were to investigate the association between socioeconomic status and its various indicators and the risk of acute myocardial infarction (AMI), and to determine whether any association found is independent of the presence of cardiovascular risk factors (CVRFs).MethodsStudy cases were matched with controls by age, sex and year of recruitment. Cases were recruited from a hospital register and controls from cross-sectional studies of the general population. The socioeconomic status was determined from educational level and social class, as indicated by occupation. Self-reported data were collected on the presence of CVRFs.ResultsThe study included 1369 cases and controls. Both educational level and social class influenced AMI risk. Among non-manual workers, there was an inverse linear relationship between educational level and AMI risk independent of CVRFs: compared with university educated individuals, the odds ratio (OR) for an AMI among those with a high school education was 1.63 (95% confidence interval [CI], 1.16–2.3), and among those with an elementary school education, 3.88 (95% CI, 2.79–5.39). No association between educational level and AMI risk was observed in manual workers. However, the AMI risk was higher in manual workers than non-manual university educated workers: in those with an elementary school education, the increased risk (OR=2.09; 95% CI, 1.59–2.75) was independent of CVRFs.ConclusionsAn association was found between socioeconomic status and AMI risk. The AMI risk was greatest in individuals with only an elementary school education, irrespective of CVRFs and social class, as indicated by occupation.

Introducción y objetivosLa posición socioeconómica se relaciona con la mortalidad cardiovascular. El objetivo de este estudio fue analizar la relación entre la posición socioeconómica y sus diferentes indicadores y el riesgo de infarto agudo de miocardio (IAM), y determinar si ésta era independiente de los factores de riesgo cardiovascular (FRCV).MétodosEstudio caso-control apareado por edad, sexo y año de reclutamiento. Los casos se obtuvieron de un registro hospitalario y los controles, de estudios transversales de base poblacional. La posición socioeconómica se determinó por el nivel de estudios y la clase social basada en ocupación. Se recogió información autodeclarada sobre los FRCV.ResultadosSe incluyó a 1.369 casos y controles. Hubo interacción entre nivel de estudios y clase social:en los trabajadores no manuales el nivel de estudios se asoció de forma lineal, inversa e independiente de los FRCV con el riesgo de IAM (estudios secundarios, odds ratio [OR] = 1,63; intervalo de confianza [IC] del 95%, 1,16–2,3; estudios primarios, OR = 3,88; IC del 95%, 2,79–5,39) respecto a universitarios; en los trabajadores manuales no se observó una asociación entre nivel de estudios y riesgo de IAM. Los trabajadores manuales presentaban un exceso de riesgo de IAM respecto a los no manuales universitarios, este exceso de riesgo era independiente de los FRCV en el grupo con estudios primarios (OR = 2,09; IC del 95%, 1,59–2,75).ConclusionesHay relación entre la posición socioeconómica y el riesgo de IAM. El grupo de la población con nivel de estudios primarios presenta mayor riesgo de IAM que es independiente de los FRCV y de la clase social basada en la ocupación.