Effects of Lowering Dialysate Calcium Concentration on Carotid Intima-Media Thickness and Aortic Stiffness in Patients Undergoing Maintenance Hemodialysis: A Prospective Study.
The study aimed to prospectively evaluate the effects of lowering the dialysate calcium concentration (DCa) to 1.25 mmol/l on Chinese patients undergoing maintenance hemodialysis (MHD), which are largely unknown to date.



A singer-center, prospective, randomized trial was conducted for 2 years. The DCa in one group was decreased from 1.5 to 1.25 mmol/l but there was no change in the other group. The clinical outcomes, biochemical parameters, medicine treatments and markers of vascular change were compared among the 2 groups at different time intervals.



At baseline, the groups were similar with respect to serum levels of calcium, phosphorus, intact parathyroid hormone and fibroblast growth factor-23 as well as carotid intima-media thickness (cIMT) and carotid-femoral pulse wave velocity (cf-PWV). It was found that the serum phosphorus concentration in the lower DCa group had decreased markedly at 2-year follow-up (0-month: 7.13 ± 1.56 mg/dl; 24-month: 5.92 ± 1.73 mg/dl; p = 0.005). Serum calcium (p = 0.018), cIMT (p = 0.029) and cf-PWV (p = 0.024) in DCa 1.25 group were significantly lower than those in 1.5 group at the 24-month visit. Kaplan-Meier curve revealed that patients in DCa 1.25 group had a better rate of survival. In the multivariate Cox regression analysis, cIMT (HR 1.010; 95% CI 1.002-1.217; p = 0.015) and cf-PWV (HR 1.265; 95% CI 1.022-1.567; p = 0.031) were potential risk factors for mortality in those patients. Importantly, we showed that the average change in these 2 risk variables were both associated with the average change in levels of serum calcium and phosphorus.



Our results indicate that lowering DCa to 1.25 mmol/l may be suitable for the MHD patients in our unit.
Department of Nephrology and Hemodialysis, The First Affiliated Hospital of Harbin Medical University, Harbin, China.
Zhangxiu
Z
He
Lei
L
Cui
Chunyuan
C
Ma
Hong
H
Yan
Tanyong
T
Ma
Lirong
L
Hao
D000328:Adult; D000368:Aged; D001011:Aorta / Q000473:pathology*; D015415:Biomarkers; D002118:Calcium / Q000009:adverse effects; D059168:Carotid Intima-Media Thickness; D015314:Dialysis Solutions / Q000737:chemistry; D004573:Electrolytes / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000009:adverse effects; D016896:Treatment Outcome; D059289:Vascular Stiffness / Q000187:drug effects
D015415:Biomarkers; D015314:Dialysis Solutions; D004573:Electrolytes; D002118:Calcium