Abstract 1169: Trends in the Risk of Fatal and Non-Fatal Myocardial Infarction Following a First Hospitalization for Stroke between 1986–2005 in Scotland
Introduction The risk of a myocardial infarction (MI) following a stroke has only been examined in small cohorts or randomized trials. We aimed to describe the risk of MI following a first stroke in a whole country over a 20 year period.
Methods Linked hospitalization and mortality data from Scotland, from 1986–2005, were used to identify all first hospitalizations where stroke was coded in the principal diagnostic position at discharge. Subsequent fatal and non-fatal MIs were identified at 30 days and 30 days-1 year. Cox regression was used to model events adjusted for comorbidities, age, socioeconomic deprivation, stroke subtype and year of admission in men and women.
Results From 1986–2005 70726 men and 86931 women were admitted with a first stroke. At 30 days 873 MIs (857 fatal) occurred in men and 1024 (1000 fatal) in women, a cumulative incidence of 1.2%(95% CI 1.1–1.3%) and 1.4%(1.3–1.5%) respectively. At 30 days -1 year the respective figures were 1080 (849) and 1248 (995) with a cumulative incidence of 2.7%(2.5–2.9) and 2.6%(2.4 – 2.7). The risk of MI was lower in women than in men HR=0.85(0.77– 0.94) at 30 days and 0.85(0.78 – 0.92) at 30 days to 1 year. The risk of MI at 30 days fell significantly over time (2005 vs 1986) in men HR=0.57 (0.41– 0.77) but not in women 0.76(0.49–1.19). The risk at 1 year in men was 0.69(0.46 – 1.04) and 1.07(0.72–1.57) in women. The strongest predictor of MI at 30 days was a history of coronary heart disease, HR=2.24(2.02–2.49) in men and 2.12(1.84 – 2.25) in women. This remained at 1 year, HR=2.17(1.89 – 2.48) in men and 2.00(1.76 – 2.28) in women.
Conclusion We have quantified the risk of MI at 30 days and 30 days-1 year following a first hospitalization with stroke. Between 1986 – 2005, the risk of a fatal or non-fatal MI at 30 days fell significantly in men but not women. The risk at 30 days - 1 year did not change over time. If favorable trends in risk reduction are to be realized in both men and women then aggressive secondary prevention is required.