Association between Advanced Glycation End-Products and Sarcopenia in Patients with Chronic Kidney Disease

Background: In patients with chronic kidney disease (CKD), there is an overproduction and accumulation of advanced glycation end-products (AGEs). Since AGEs may have detrimental effects on muscular trophism and performance, we evaluated whether they may contribute to the onset of sarcopenia in CKD patients. Methods: We enrolled 117 patients. The AGEs were quantified by fluorescence intensity using a fluorescence spectrophotometer and soluble receptor for AGE (sRAGE) isoforms by ELISA. As for the sarcopenia definition, we used the European Working Group on Sarcopenia in Older People (EWGSOP2) criteria. Results: The average age was 80 +/- 11 years, 70% were males, and the mean eGFR was 25 + 11 mL/min/1.73 m(2). Sarcopenia was diagnosed in 26 patients (with a prevalence of 22%). The sarcopenic patients had higher levels of circulating AGEs (3405 +/- 951 vs. 2912 +/- 722 A.U., p = 0.005). AGEs were higher in subjects with a lower midarm muscle circumference (MAMC) (3322 +/- 919 vs. 2883 +/- 700 A.U., respectively; p = 0.005) and were directly correlated with the gait test time (r = 0.180, p = 0.049). The total sRAGE and its different isoforms (esRAGE and cRAGE) did not differ in patients with or without sarcopenia. Conclusions: In older CKD patients, AGEs, but not sRAGE, are associated with the presence of sarcopenia. Therefore, AGEs may contribute to the complex pathophysiology leading to the development of sarcopenia in CKD patients.