Effects of in-center nocturnal versus conventional hemodialysis on endothelial dysfunction

Cardiovascular disease is the leading cause of morbidity and mortality in patients with end-stage renal disease who undergo hemodialysis and endothelial dysfunction is an early key step in the development of atherosclerosis. The aim of this study was to investigate the effect of thrice-weekly in-center nocturnal hemodialysis (INHD, 8 h per session and three sessions per week) and conventional hemodialysis (CHD, 4 h per session and three sessions per week) on endothelial dysfunction in patients with end-stage renal disease. 32 INHD and 58 matched CHD patients were enrolled, baseline and 12-month measures of blood pressure (BP), serum calcium and phosphorus, serum intact PTH (iPTH) and brachial artery flow-mediated dilation (FMD) were collected and analyzed. Baseline characteristics were similar between groups except that serum phosphorus and calcium × phosphorus were higher in the INHD group. At the 12-month follow-up, there was a significant increase in FMD (6.0 ± 1.5% to 7.1 ± 1.8%, P < 0.01) in INHD patients. Multivariate analysis showed that FMD was inversely correlated with systolic BP (SBP) (β = -0.485, P < 0.01), diastolic BP (DBP) (β = -0.428, P < 0.01), iPTH (β = -0.405, P < 0.01) and serum phosphorus level (β = -0.375, P < 0.01). There was no significant change in FMD in the CHD group. Compared with CHD, INHD improves endothelial function, and control of serum phosphorus is associated with the improvement of endothelial function.