The effects of non-calcium-based phosphate binders versus calcium-based phosphate binders on cardiovascular calcification and bone remodeling among dialysis patients: a meta-analysis of randomized trials

Background: Vascular calcification significantly increases the rates of cardiovascular mortality in hemodialysis (HD) patients. Abnormalities in mineral metabolism may play a role in the pathogenesis of arterial calcification. Whether patients treated with non-calcium-based phosphate binders had reduced aortic vascular calcification compared to those treated with calcium-based phosphate binders is still unclear. Methods: We searched multiple databases for studies published through August 2013 that evaluated the effects of non-calcium-based phosphate binders (NCBP) versus calcium-based phosphate binders (CBP) on cardiovascular calcification and bone remodeling among dialysis patients. We summarized test performance characteristics with the use of forest plots, fixed and random effects models, and Egger regression test. Results: Eighteen eligible randomized controlled trials totaling 3676 patients were included. Meta-analysis results showed NCBP could significantly attenuate the progression of coronary artery calcification than CBP (WMD: -144.62, 95% CI: -285.62 to -3.63). The serum calcium levels significant lower in NCPB group than in CPB groups (WMD: -0.26, 95% CI: -0.37 to -0.14), but the serum iPTH levels were significantly higher in NCPB groups (WMD: 57.1, 95% CI: 13.42 to 100.78). The osteoid volume and osteoblast numbers were significant higher in NCPB group than in CPB group (WMD: 1.75, 95% CI: 0.78 to 2.73 for osteoid volume; WMD: 4.49, 95% CI: 1.83 to 7.15 for osteoblast numbers). The Egger regression test also showed no potential publication bias (p = 0.725). Conclusions: Based on available data, NCBPs have equally effective with CBPs for serum phosphate control. But there was significantly lower incidence of coronary artery calcification and a significant higher bone formatting rate in NCBP groups than in CBP groups. So we recommend NCBPs as phosphate binders for HD patients.