Prospective study of modifiable risk factors of arterial hypertension and left ventricular hypertrophy in pediatric hemodialysis patients.

Introduction Fluid and salt overload in dialysis patients result in high blood pressure (BP), left ventricular hypertrophy (LVH) and hemodynamic instability, resulting in cardiovascular morbidity and mortality. Methods Analysis of 910 pediatric patients on maintenance hemodialysis/hemodiafiltration (HD/HDF), prospectively followed with 2758 observations recorded every 6-months in the International Pediatric Hemodialysis Network. Results Uncontrolled hypertension was present in 55% of observations, with 27% of patients exhibiting persistently elevated pre-dialysis BP. Systolic and diastolic, height- and age-standardized BP (BP-SDS) were independently associated with number of antihypertensive medications (OR=1.47 [1.39-1.56], 1.36 [1.23-1.36]) and interdialytic weight gain (IDWG; 1.19 [1.14-1.22], 1.09 [1.06-1.11]). IDWG was related to urine output (OR=0.27 [0.23-0.32]) and dialysate sodium (dNa; 1.06 [1.01-1.10]; all p<0.0001). In subjects with pre-dialysis and 24h-BP measurements, the prevalence of masked hypertension was 24%, and HD versus HDF use was an independent risk factor of elevated MAP-SDS (OR=2.28 [1.18-4.41], p=0.01).51% of 1135 echocardiograms demonstrated LVH. Modifiable risk factors included pre-dialysis systolic BP-SDS (OR=1.06 [1.04-1.09], p<0.0001), blood hemoglobin (0.97 [0.95-0.99], HD versus HDF modality (1.09 [1.02-1.18], p=0.01) and IDWG (1.02 [1.02-1.03], p=0.04). Additionally HD modality increased the risk of LVH progression (OR=1.23 [1.03-1.48]). Intradialytic hypotension (IDH) was prevalent in patients progressing to LVH and independently associated with pre-dialysis BP-SDS below 25th percentile, lower number of antihypertensives, HD versus HDF modality, ultrafiltration rate and urine output, but not with dNa. Conclusions Uncontrolled hypertension and LVH are common in pediatric hemodialysis, despite intense pharmacological therapy. Outcome may improve with use of HDF, and superior anemia and IDWG control; the latter via lowering dNa, without increasing the risk of IDH.