FC 133HEMODIAFILTRATION IS ASSOCIATED WITH REDUCED INFLAMMATION AND INCREASED BONE TURNOVER COMPARED TO CONVENTIONAL HEMODIALYSIS IN CHILDREN - THE HDF, HEART AND HEIGHT (3H) STUDY

Abstract

Abstract Background and Aims Children on dialysis have a high burden of bone related comorbidities and fractures. We report a post-hoc analysis of the HDF-Hearts-Height study to determine the prevalence and risk factors for mineral bone disease in children on hemodiafiltration (HDF) and conventional hemodialysis (HD). Method 144 children were included in baseline cross-sectional analysis, of which 103 (61 HD, 42 HDF) completed 12-month follow-up. Biomarkers of bone formation and resorption, inflammatory markers, fibroblast growth factor-23 (FGF23) and klotho were measured. Results Inflammatory markers interleukin-6 [IL-6], tumor necrosis factor-alfa [TNF-α], and high-sensitivity CRP [hsCRP] were lower in the HDF compared to HD cohorts at baseline and 12 months (p<0.001). Concentrations of bone formation (bone-specific alkaline phosphatase, BAP) and resorption (tartrate-resistant acid phosphatase 5b [TRAP5b]) markers were comparable between cohorts at baseline, but after 12-months the BAP/TRAP5b ratio increased in HDF (p=0.004) and was unchanged in HD (p=0.44). On adjusted analysis the BAP/TRAP5b ratio was 2.66-fold lower (95%CI -3.91, -1.41; p<0.0001) in HD compared to HDF. FGF23 was comparable between groups at baseline (p=0.52) but increased in HD (p<0.0001) and remained static in HDF (p=0.34) at 12-months. Klotho levels were similar between groups and unchanged during follow-up. The FGF23/klotho ratio was 3.86-fold higher (95% CI 2.15, 6.93; p<0.0001) in HD compared to HDF. Conclusion We conclude that children on HDF have increased bone turnover, an attenuated inflammatory profile and lower FGF23/klotho ratios compared to those on HD. Long-term studies are required to determine the effect, if any, of an improved bone biomarker profile on fracture risk and growth.