Socioeconomic environment and recurrent coronary events after initial myocardial infarction

Abstract

Purpose: Longitudinal data linking area-level socioeconomic status (SES) to repeated acute coronary syndrome (ACS) events are limited. Using multiple failure-time data, we examined the association between neighborhood SES and ACS in a community-based cohort of myocardial infarction (MI) survivors.

Methods: Consecutive patients aged 65 years or younger discharged from eight hospitals in central Israel after first MI in 1992-1993 were followed through 2005. Recurrent MI and unstable angina pectoris (UAP) leading to hospitalization were recorded. Neighborhood SES was assessed through a composite census-derived index developed by the Israel Central Bureau of Statistics. Different variance-corrected proportional hazards models were used to account for multiple recurrent events: Andersen-Gill, Wei-Lin-Weissfeld (WLW), and Prentice-Williams-Peterson.

Results: During follow-up, 531 recurrent MIs and 1584 UAP episodes occurred among 1164 patients. Adjusting for known prognostic factors and individual SES using the Andersen-Gill model, higher estimated hazards were associated with poor neighborhood SES (hazard ratio, 1.55; 95% confidence interval [CI], 1.13-2.14 for recurrent MI; and hazard ratio, 1.48; 95% CI, 1.22-1.79 for UAP; in the 5th vs. 95th percentiles). The WLW and Prentice-Williams-Peterson models yielded similar results. When the two outcomes were combined, the WLW-derived hazard ratio was 1.64 (95% CI, 1.39-1.93).

Conclusions: MI survivors living in a deprived neighborhood are at higher risk of repeated hospital admissions because of ACS. Secondary prevention initiatives should incorporate multilevel approaches to increase effectiveness and reduce geographic health disparities.