DIAGNOSTIC DISCREPANCY AND STAGING RECLASSIFICATION BETWEEN CYSTATIN C AND CREATININE-BASED EGFR IN SARCOPENIC ADULTS: A CROSS-SECTIONAL STUDY

Background: Sarcopenia leads to reduced skeletal muscle mass, causing lower endogenously generated serum creatinine and subsequent overestimation of renal clearance when using creatinine based estimated glomerular filtration rate (〖eGFR 〗_cr ). Serum cystatin C, produced at a constant rate by nucleated cells, is largely independent of muscle mass. This study aimed to evaluate the extent of diagnostic discordance and stage reclassification between 〖eGFR 〗_cr and cystatin C-based eGFR (〖eGFR 〗_cys ) in sarcopenic older adults. Methods: An analytical cross-sectional study was conducted among 260 sarcopenic patients aged ≥60 years recruited from a tertiary-care hospital. Sarcopenia was defined using standard criteria combining reduced handgrip strength and low appendicular skeletal muscle mass index. Serum creatinineand cystatin C were determined. 〖eGFR〗-cr