Combined association of key risk factors on ischaemic outcomes and bleeding in patients with myocardial infarction

OBJECTIVE: In patients with myocardial infarction (MI), risk factors for bleeding and ischaemic events tend to overlap, but the combined effects of these factors have scarcely been studied in contemporary real-world settings. We aimed to assess the combined associations of established risk factors using nationwide registries. METHODS: Using the Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies registry, patients with invasively managed MI in 2006–2014 were included. Six factors were assessed in relation to cardiovascular death (CVD)/MI/stroke, and major bleeding: age ≥65, chronic kidney disease, diabetes, multivessel disease, prior bleeding and prior MI. RESULTS: We studied 100 879 patients, of whom 20 831 (20.6%) experienced CVD/MI/stroke and 5939 (5.9%) major bleeding, during 3.6 years median follow-up. In adjusted Cox models, all factors were associated with CVD/MI/stroke, and all but prior MI were associated with major bleeding. The majority (53.5%) had ≥2 risk factors. With each added risk factor, there was a marked but gradual increase in incidence of the CVD/MI/stroke. This was seen also for major bleeding, but to a lesser extent, largely driven by prior bleeding as the strongest risk factor. CONCLUSIONS: The majority of patients with MI had two or more established risk factors. Increasing number of risk factors was associated with higher rate of ischaemic events. When excluding patients with prior major bleeding, bleeding incidence rate increased only minimally with increasing number of risk factors. The high ischaemic risk in those with multiple risk factors highlights an unmet need for additional preventive measures.