Long-term survival of Icelandic women following acute myocardial infarction

Abstract

Objective. To evaluate the impact of sex on treatment and survival after acute myocardial infarction (AMI) in Iceland. Methods. A retrospective, nationwide cohort study of patients with STEMI (2008–2018) and NSTEMI (2013–2018) and obstructive coronary artery disease. Patient and procedural information were obtained from a registry and electronic health records. Survival was estimated with Kaplan–Meier method and Cox regression analysis used to identify risk factors for long-term mortality. Excess mortality from the AMI episode was estimated by comparing the survival with age- and sex-matched population in Iceland at 30-day interval. Results. A total of 1345 STEMI-patients (24% women) and 1249 NSTEMI-patients (24% women) were evaluated. Women with STEMI (mean age: 71 ± 11 vs. 67 ± 12) and NSTEMI (mean age: 69 ± 13 vs. 62 ± 12) were older and less likely to have previous cardiovascular disease. There was neither sex difference in the extent of coronary artery disease nor treatment. Although crude one-year post-STEMI survival was lower for women (88.7% vs. 93.4%, p =.006), female sex was not an independent risk factor after adjusting for age and co-morbidities after STEMI and was protective for NSTEMI (HR 0.67, 95% CI: 0.46–0.97). There was excess 30-day mortality in both STEMI and NSTEMI for women compared with sex-, age- and inclusion year-matched Icelandic population, but thereafter the mortality rate was similar. Conclusion. Women and men with AMI in Iceland receive comparable treatment including revascularization and long-term survival appears similar. Prognosis after NSTEMI is better in women, whereas higher early mortality after STEMI may be caused by delays in presentation and diagnosis.