Abstract 11784: The Estimated Appendicular Skeletal Muscle Mass Predicts Adverse Outcomes in Patients Under 65 Years With Coronary Artery Disease

Background: The impact of frailty, evaluated by the appendicular skeletal muscle mass (ASM) has been recognized as a predictor of adverse prognosis in elder patients with coronary artery disease (CAD). In recent years, formulas for estimating ASM using height, weight, sex, and age have been proposed for Asian population. However, a simple equation for estimating ASM has not been well validated in clinical, especially in younger patients. Methods: We enrolled 811 patients under 65 years with CAD who underwent percutaneous coronary intervention (PCI) at our hospital between 2010 and 2017. The mean age was 57 years and 89.6% were men. Patients were divided into 2 groups based on each ASM index (ASMI). Low ASMI was defined as the 20% lowest percentile of the study population (low ASMI; male <7.6 and female <5.5, high ASMI; male 7.6≤ and female 5.5≤). ASM was calculated by the following formula: 0.193 х bodyweight + 0.107хheight – 4.157 х gender – 0.037 х age – 2.631. Primary endpoint was 4P MACE (cardiovascular death, non-fatal myocardial infarction and non-fatal stroke and admission for heart failure). Results: During the median follow-up period of 5.2 years, cumulative incidence of events were significantly higher in the low ASMI group (Figure). After adjustment for important covariates, patients in the low ASMI groups had significantly higher all-cause mortality and MACE than those in the high ASMI groups (Crude; HR 1.98, 95% CI 1.16-3.24, p = 0.014, Model 1; HR 1.91, 95% CI 1.11-3.16, p = 0.02, Model 2; HR 2.23, 95% CI 1.18-4.02, p = 0.015) Conclusions: A low ASMI evaluated by a simple equation is an independent predictor of 4P MACE in younger patients with CAD.