The Effects of Acetate-Free Citrate-Containing Dialysate on Calcium Metabolism and Fatigue in Patients on Maintenance Hemodialysis

Although the significance of acetate-free citrate with 3.0 mEq/L Ca-containing-dialysate (A(−)D) has been reported, its effective Ca level and the overtreatment needed to correct metabolic acidosis on the basis of serum whole parathyroid hormone (wPTH) and arterial pH have not been evaluated in detail. Furthermore, recent reports have suggested the beneficial effect of citrate on fatigue, which is a significant risk for cardiovascular disease. Thirty-two hemodialysis patients receiving acetate with 2.75 mEq/L Ca-containing dialysate (A(+)D) participated in the present A(+)D to A(–)D one-arm switch study over 4 weeks. Predialysis wPTH increased significantly from 85.1 ± 59.0 pg/mL during hemodialysis A(+)D to 106.8 ± 78.8 pg/mL (p = 0.0015) after 2 weeks of A(–)D treatment. Predialysis arterial pH and bicarbonate levels significantly increased from 7.335 ± 0.037 to 7.370 ± 0.035 (p < 0.0001) and from 19.6 ± 2.1 mEq/L to 21.3 ± 1.7 mEq/L (p = 0.0001), respectively, whereas post-dialysis arterial pH and bicarbonate levels significantly increased from 7.447 ± 0.022 to 7.473 ± 0.027 (p < 0.0001) and from 25.2 ± 1.0 mEq/L to 28.1 ± 1.0 mEq/L (p < 0.0001). When all patients were divided into two equal-sized groups by fatigue score, the improvement in the fatigue score was significantly greater in the high group (∆1.8 ± 3.7) than in the low group (∆–0.8 ± 2.3) (p = 0.0252). This study demonstrated that the effective Ca level might be significantly lower in A(−)D than in A(+)D and metabolic acidosis was improved more strongly in A(–)D relative to that in A(+)D because of the higher bicarbonate concentration in A(–)D. Furthermore, A(–)D had a beneficial effect on intradialytic hemodynamics and fatigue sensation.