Cardiovascular risk in post-myocardial infarction patients: nationwide real world data demonstrate the importance of a long-term perspective.
Level 3 - non-randomized controlled study
Retrospective nationwide observational cohort study using linked registry data
PubMed 25586123 · doi:10.1093/eurheartj/ehu505
What was done
This retrospective cohort study linked Swedish national morbidity, mortality, and medication registries. Among 108,315 patients hospitalized for a primary myocardial infarction (MI) between July 1, 2006, and June 30, 2011, 97,254 patients who survived at least one week post-discharge were analyzed. The primary composite endpoint of non-fatal MI, non-fatal stroke, or cardiovascular death was evaluated over the first 365 days and from day 366 onward using Kaplan-Meier analysis and Cox proportional hazards modelling.
What was found
The cumulative risk of the composite endpoint was 18.3% during the first 365 days post-index MI. Independent predictors of ischemic events or death included older age (60-69 vs. <60 years: HR 1.37, 95% CI 1.30-1.45; 70-79 years: HR 2.13, 95% CI 2.03-2.24; >80 years: HR 3.96, 95% CI 3.78-4.15), prior MI (HR 1.44, 95% CI 1.40-1.49), prior stroke (HR 1.49, 95% CI 1.44-1.54), diabetes (HR 1.37, 95% CI 1.34-1.40), heart failure (HR 1.57, 95% CI 1.53-1.62), and absence of index MI revascularization (HR 1.88, 95% CI 1.83-1.93). Among patients who survived without an event during the first year, the composite endpoint risk was 20.0% over the subsequent 36 months.
Why it matters
Cardiovascular event risk remains persistently high years after an initial myocardial infarction, demonstrating the necessity of long-term secondary prevention and surveillance beyond the first year.
Limits
The study is an observational retrospective registry analysis subject to unmeasured confounding and coding accuracy. Findings reflect the Swedish healthcare system and population, which may not generalize to settings with different care pathways. The abstract does not report data on long-term medication adherence, lifestyle factors, or angiographic details.
Cited by
- supports The risk of experiencing a recurrent heart attack is highest during the 6 to 12 months immediately following a myocardial infarction.