Effect of dialysate sodium concentration on intradialytic blood pressure variability and related clinical outcomes: A single-center prospective cohort study.

Dialysate sodium concentration (dNa) is a key determinant of hemodynamic stability during hemodialysis. However, the clinical relevance of small reductions in dNa remains uncertain, particularly regarding intradialytic blood pressure variability and ultrafiltration efficiency. This study aimed to evaluate the effect of reducing dialysate sodium from 140 mmol/L to 138 mmol/L on intradialytic systolic and diastolic blood pressure variability, interdialytic weight change, and ultrafiltration adequacy. This prospective, single-center cross-over study included ten adult hemodialysis patients (N = 10) treated sequentially with dNa concentrations of 140 and 138 mmol/L for 2 consecutive months (12 sessions per phase). Paired comparisons were performed using Wilcoxon signed-rank tests. No significant differences were observed between 140 mmol/L and 138 mmol/L dialysate sodium in systolic or diastolic BP variability, interdialytic weight gain, intradialytic weight loss, or ultrafiltration adequacy (all P > .05). Median systolic BP variability was 15.9 mm Hg (IQR 13.0-18.2) vs 14.3 mm Hg (IQR 12.4-18.4) (HL diff 2.00 [95 % CI-7.44, 6.53]); diastolic BP variability 7.9 mm Hg (IQR 6.8-11.0) vs 7.9 mm Hg (IQR 7.7-8.8) (HL diff-0.15 [95 % CI-3.90, 3.35]). Exploratory subgroup trends (greater systolic variability in females, lower in CAD patients under 138 mmol/L) were not statistically reliable due to small group sizes. A modest 2 mmol/L reduction in dialysate sodium was not associated with clear short-term changes in hemodynamic or fluid-related effects. Larger multicenter studies are needed to clarify the clinical impact of individualized sodium prescriptions.