Serum creatinine to cystatin C ratio is associated with major adverse cardiovascular events in patients with obstructive coronary artery disease.

BACKGROUND & AIMS: Sarcopenia is a clinical syndrome that features muscle atrophy and weakness, and has been associated with cardiovascular events and poor clinical outcomes. Recently, the sarcopenia index (SI) was developed as a simple screening tool based upon the serum creatinine to cystatin C (CysC) ratio. We investigated the association between SI and the prevalence of major adverse cardiovascular events (MACE) in patients with obstructive CAD. METHODS & RESULTS: Between January 2010 and December 2018, patients with angina pectoris and obstructive CAD requiring coronary artery intervention were enrolled. Serum levels of CysC and other biomarkers were assessed. Patients were divided into two groups according to the SI ([Cr/CysC] x 100). Demographic characteristics and clinical outcomes of the two groups were evaluated. A total of 427 patients (79.6% men, mean age 69.55 ± 12.04 years) were enrolled. Patients with SI < 120 (n = 214, 28%) were older, more likely to be of the female gender, and to have more hypertension and congestive heart failure (all p < 0.05). The prevalence of major adverse cardiovascular events (MACE) composed of myocardial infarction, stroke, and all-cause mortality was higher in patients with lower SI (p = 0.026). After adjusting for potential confounding factors, multivariate Cox regression (hazard ratio 2.08, p = 0.045) and Kaplan-Meier analyses (log-rank p = 0.0371) revealed that lower SI was significantly associated with a higher prevalence of MACE. CONCLUSIONS: Serum creatinine to cystatin C ratio (SI) may be a useful surrogate marker to predict the future prevalence of MACE in patients with obstructive CAD.