4597 REDUCED VO2PEAK IN PATIENTS WITH END-STAGE RENAL DISEASE: UNVEILING THE HIDDEN IMPLICATION OF CEREBRAL AND MUSCULAR HEMODYNAMICS

Abstract Background and Aims Aerobic fitness, as reflected by maximal oxygen (O2) uptake (VO2peak), is impaired in chronic kidney disease (CKD) patients. The mechanisms underlying this impairment remain to be explored. This study aimed to investigate whether CKD influence O2 supply including O2 delivery and release to the brain and active muscles during maximal physical exercise. Method Twenty three male undergoing dialysis therapy (HD group) and twenty three healthy males (CTR group) performed exhaustive incremental exercise to determine VO2peak. Throughout the exercise, near-infrared spectroscopy allowed investigation of changes oxyhemoglobin (∆O2Hb), deoxyhemoglobin (∆HHb), and total hemoglobin (∆THb) in the prefrontal cortex and in the vastus lateralis muscle. Results VO2peak was significantly lower in HD group compared to CTR. Muscular ∆HHb changes was impaired in HD patients (Figure 1). Increase in ∆THb (i.e., muscle blood volume) was significantly blunted in HD in both muscular and cerebral side (Figure 1 and 2). Also, HD patients had impaired changes in ∆O2Hb during the exercise compared to CTR group (Figure 1 and 2). A positive correlation has been observed between VO2peak and muscular blood colume (∆THb) for both groups. Figure 1: Recordings made by NIRS from the vastus lateralis change in ΔO2Hb (A) ΔHHb (B) and ΔTHb (C).Values are means ±SD. HD, black triangles; CTRL, white triangles. ∗p