Educational differences in 28-day and 1-year survival after hospitalization for incident acute myocardial infarction - A CVDNOR project

Purpose: To study potential differences in survival across levels of education in patients hospitalized for an incident acute myocardial infarction (AMI) during 2001-2009 in Norway. Methods: The Cardiovascular Disease in Norway (CVDNOR) project have collected data on all AMI hospitalizations between 1994 and 2009 through patient administrative systems at Norwegian hospitals and linked the data to the Cause of Death Registry, the Population Registry and the National Education Database. Incident AMI was defined as a hospitalization with an AMI-diagnosis (ICD9:410, ICD10: I21-I22) without any AMI-events the previous 7 years. Education were categorized as basic or no education, upper secondary education and tertiary education (college/university). Differences in 28-day and 1-year survival after an incident AMI across education levels where studied using Kaplan-Meier survival curves and Cox regression with adjustment for age, sex, calendar year, marital status and country of birth. Patients were followed until December 31st 2010. Results: 113 797 incident AMIs were identified (39.5% women). Median follow-up time was 5.4 years. Adjusted HRs (95% CI) for tertiary vs. basic education for 28-day and 1-year survival were 0.84 (0.80-0.89) and 0.82 (0.79-0.86). P-trend across the three educational groups were <0.001. Stratification on calendar year revealed increasing disparities in survival across educational groups during 2001-2009. Stratification on gender and age group (30-64 and ≥65) showed stronger associations between education and survival among women aged 30-64. 1-year survival after incident AMI 1-year survival after incident AMI Conclusion: Compared to patients with higher education, those with only basic education had significantly poorer 28-day and 1-year survival after an incident AMI. The disparities were largest among women < 65 years of age.