MO078HEMODIAFILTRATION MAINTAINS A SUSTAINED IMPROVEMENT IN BP COMPARED TO CONVENTIONAL HEMODIALYSIS IN CHILDREN - THE HDF, HEART AND HEIGHT (3H) STUDY

Abstract

Abstract Background and Aims Hypertension is prevalent in children on dialysis and associated with left ventricular hypertrophy, cardiovascular disease and mortality. We studied the effect of different dialysis modalities (conventional hemodialysis [HD] vs hemodiafiltration [HDF]) on BP and risk factors affecting the evolution of BP over a one-year follow-up. Method This is a post-hoc analysis of the “3H - HDF-Hearts-Height” dataset, a multicenter, non-randomized, parallel-arm intervention study. The time–averaged 24-h mean arterial pressure (MAP) was used for the analyses and hypertension defined as 24-h MAP standard deviation score exceeding the 95th percentile. Results All 133 children who completed 12 months follow-up in the 3H study were included in this post - hoc analysis. 78 (74%) were on HD and 55 (77%) on HDF. At baseline MAP-SDS was > 95th percentile in 64 (82%) of children on HD and 23 (41.8%) patients on HDF, but these data are skewed by a high percentage of prevalent dialysis patients in the study. 43 (55%) of HD patients and 23 (42%) of HDF patients were on antihypertensive medications, and uncontrolled hypertension (BP>95th centile on medications) was present in 38 (88%) of HD patients and 6 (25%) of HDF patients. In the stepwise logistic regression at baseline, independent risk factors for hypertension were gender (OR 2.29; 95%CI 1.06–4.96; p=0.04) and inter-dialytic weight gain at baseline (OR 1.3; 95%CI 1.1–1.55; p=0.004). Over the one-year study period, MAP-SDS increased by 39% in HD patients and 12% in HDF patients (p< 0.001) (Figure). Significant risk factors for hypertension over time were dialysis modality (OR for HD compared to HDF 7.65; 95% CI 3.23 – 18.12; p< 0.001), inter-dialytic weight gain (OR 1.21; 95% CI 1.05 – 1.39; p=0.007), and dialysate sodium (for 1 mmol/L increase in dialysate sodium MAP-SDS increased by 1.1mmHg ; 95% CI 1.01 – 1.21; p=0.04). Conclusion Children on HD compared to HDF had a 7.6-fold higher 24-hr MAP-SDS and a sustained increase in BP over the one-year study period. Higher inter-dialytic weight gain and higher dialysate sodium levels were associated with a higher MAP-SDS in both groups.