[Effect of educational level on the prognosis of acute myocardial infarction]

Abstract

Background: Socioeconomic status is associated with cardiovascular mortality.

Aim: To evaluate the effect of educational level, on the prognosis of patients with acute myocardial infarction in Chile.

Material and methods: Cohort study of 3,636 patients aged 63.1 ± 13.2 years, 27% women, hospitalized in 16 centers participating in the Chilean Myocardial Infarction Registry (GEMI) between 2009 and 2012. Vital status was obtained from the National Mortality Database. Patients were divided, according to educational level, in four groups, namely none (no formal education), basic (< 8 years), secondary (8-12 years) and tertiary (> 12 years). Crude and adjusted (age, sex, cardiovascular risk factors and treatments) hazard ratios (HR) were estimated using Cox regression models.

Results: The distribution by educational level was 3.2% none, 31.8% basic, 43.0% secondary and 22.0% tertiary. During a median follow-up period of 22 months (interquartile range 11-37 years), 631 patients died (17.3%), of whom 198 died during hospitalization (5.5%). The 30 day case-fatality rate according to educational level was 3.4% in tertiary, 4.7% in secondary, 11.9% in basic, 19.1% in none (p < 0.0001). Among patients surviving the first 30 days, the case-fatality rate was 4.4%, 8.6%, 14.6% and 27.0%, respectively (p < 0.0001). The increased risk of death for groups with lower education compared with individuals with tertiary education, persisted in the multivariate analysis with a hazard ratio for secondary education 1.58 (95% confidence intervals (CI), 1.18-2.10); for basic education 1.90 (95% CI, 1.41-2.47) and for none 3.50 (95% CI, 2.35-5.21).

Conclusions: A lower educational level was associated with a worse prognosis in patients with myocardial infarction, even after controlling for potential confounding factors.