Effect of Ascorbic Acid on Mineral and Bone Disorders in Hemodialysis Patients: a Systematic Review and Meta-Analysis

• Published in: Kidney & blood pressure research Vol. 43; no. 5; pp. 1459 - 1471
• Main Authors: Ke, Guibao, Huang, Junlin, Zhu, Yue, Yang, Jia, Zhang, Yamei, Chen, Lvlin, Hu, Juan, Tao, Shaoqiang, Hu, Yao, Yang, Dehua, Liu, Shuangxin
• Format: Journal Article
• Language: English
• Published: Basel, Switzerland S. Karger AG 01.01.2018; Karger Publishers
• Subjects: Ascorbic acid; Ascorbic Acid - pharmacology; Ascorbic Acid - therapeutic use; Bone diseases; Bone Diseases - drug therapy; Bone Diseases - etiology; Calcium; Calcium - blood; Calcium phosphates; Cardiovascular diseases; Chronic kidney disease-mineral bone disorders; Clinical trials; Confidence intervals; Dialysis; Dietary supplements; Disorders; Hemodialysis; Humans; Kidney diseases; Kidney Failure, Chronic - complications; Kidney Failure, Chronic - therapy; Menopause; Meta-analysis; Minerals; Minerals - blood; Mortality; Nutrition; Original Paper; Parathyroid; Parathyroid hormone; Parathyroid Hormone - blood; Peritoneal dialysis; Phosphate; Phosphorus - blood; Randomized Controlled Trials as Topic; Renal Dialysis; Side effects; Systematic review; Vitamin D; Ascorbic acid; Calcium; Hemodialysis; Parathyroid hormone; Chronic kidney disease-mineral bone disorders; Phosphate
• ISSN: 1420-4096; 1423-0143
• DOI: 10.1159/000493661

Background/Aims: Hemodialysis (HD) patients often have inadequate nutrition, especially with respect to ascorbic acid (AA). It is reported that every HD session may cause a 50%– 75% decrease in plasma AA levels. Some studies have shown that supplementation of AA can change the outcome of chronic kidney disease-mineral bone disorders (CKD-MBD), but the effect of AA on HD patients with CKD-MBD remains controversial. Consequently, we decided to perform a meta-analysis to evaluate the efficacy of AA supplementation in CKD-MBD patients requiring dialysis. Methods: A search was conducted using Pubmed, EMBASE, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure (CNKI), Wanfang database and VIP information database up to April 2018 for all English and Chinese language publications. The main indicators of our study were changes in serum phosphate (P), calcium (Ca) and parathyroid hormone (PTH) levels after AA treatment. The efficacy of AA was evaluated by weighted mean difference (WMD) and confidence intervals (CI). Cardiovascular events, mortality and adverse events reported during the experiment were also noted. Results: In total, 371 patients in six studies were involved in this meta-analysis. Compared to placebo, AA treatment had no positive effect on serum P (353 patients; WMD = -0.05; 95% CI, -0.3 to 0.2; I 2 = 28%) or PTH levels (275 patients; WMD = -17.04; 95%CI, -63.79 to 29.72; I 2 = 75%). The pooled mean difference of the change of Ca levels from baseline was higher in the AA therapy group versus placebo (353 patients; WMD = 0.15; 95% CI, 0.01 to 0.3; I 2 = 0%). No side effects were observed. Conclusion: Our systematic review and meta-analysis does not support prescription of AA to HD patients with CKD-MBD. AA had no positive effect on CKD-MBD patients as it couldn’t influence the serum P or PTH levels but did raise serum Ca levels in the short-term.