The impact of kidney function on outcomes following high risk myocardial infarction: findings from 27 610 patients

Abstract

Renal dysfunction is associated with poor cardiovascular outcome. We investigated the relationship of kidney function and long-term cardiovascular outcomes in patients with high risk myocardial infarction. We studied 27 610 patients from four randomized trials of acute myocardial infarction complicated by heart failure and/or LV dysfunction (LVEF ≤40%). Two trials excluded patients with serum creatinine ≥2.5 mg/dL. Patients were grouped by estimated glomerular filtration rate (eGFR) using the four-component Modification of Diet in Renal Disease equation. We used adjusted Cox proportional hazard models to compare mortality and composite cardiovascular events among eGFR groups. Median follow-up was 23 months. The eGFR was approximately normally distributed, with a mean ± SD of 69.1 ± 20.2 mL/min/1.73 m(2) . Co-morbidities were more prevalent with lower eGFR. The risk of death or composite outcome of cardiovascular death, myocardial infarction, stroke, or heart failure hospitalization increased with declining eGFR. Below 75 mL/min/1.73 m(2) , each 10 unit reduction of eGFR was associated with an adjusted hazard ratio for death of 1.13 (95% confidence interval, 1.11-1.15) and composite cardiovascular outcome of 1.09 (95% confidence interval, 1.08-1.10). Older patients (≥75 years) with low LVEF (<30%) had a higher incidence of mortality and adverse cardiovascular events across eGFR categories. Reduced eGFR is strongly and independently associated with poor cardiovascular outcome following high risk myocardial infarction. In these patients, the combination of older age and poor LV systolic function is associated with increased risk of adverse events.