Abstract 13518: Low Skeletal Muscle Mass Index is Associated With Cardiovascular Events in Patients After ST-segment Elevation Myocardial Infarction

Abstract

Introduction: Although it has been implicated the association between low skeletal muscle mass and cardiovascular diseases, the prognostic value of skeletal muscle mass in patients with ST-segment elevation myocardial infarction (STEMI) is unclear. Hypothesis: We assessed the hypothesis that low skeletal muscle mass index (SMMI) is associated with an increased risk of secondary cardiovascular events in patients with STEMI. Methods: A total of 200 patients with STEMI were enrolled. SMMI was estimated from dual-energy X-ray absorptiometry scan before discharge, and calculated by dividing appendicular skeletal muscle mass (kg) by height squared (m 2 ). The patients were divided into low and high SMMI groups using the first tertile of SMMI. Low SMMI was defined as ≤6.843 kg/m 2 for men and ≤5.321 kg/m 2 for women. All patients were followed for cardiovascular events, which consist of cardiovascular deaths, nonfatal myocardial infarctions, nonfatal ischemic strokes, and congestive heart failure. Results: During follow-up (median 340 days [interquartile ranges 298 and 389]), 15 patients experienced cardiovascular events (1 cardiovascular death, 6 myocardial infarction, 6 stroke, and 3 congestive heart failure). The event rate at 1 year after STEMI was significantly higher in patients with low SMMI (15.5%) than with high SMMI (2.5%) (log-rank p<0.001) (Figure). Even after adjustment for the propensity score which was calculated with age, gender, height, weight, risk factors and medications, patients with low SMMI had 5.8-fold higher risk of subsequent cardiovascular events compared to those without (Adjusted hazard ratio 5.86, 95% confidence interval 1.18 to 35.28, p=0.03). Conclusion: Among patients with STEMI, low SMMI was significantly and independently associated with an increased risk of future cardiovascular events.