Impact of Bioelectrical Impedance-Guided Fluid Management and Vitamin D Supplementation on Left Ventricular Mass in Patients Receiving Peritoneal Dialysis: A Randomized Controlled Trial.

ABSTRACT

RATIONALE & OBJECTIVE: Hypervolemia and vitamin D deficiency occur frequently in patients receiving peritoneal dialysis and may contribute to left ventricular (LV) hypertrophy. The effect of bioelectrical impedance analysis (BIA)-guided volume management or vitamin D supplementation on LV mass among those receiving peritoneal dialysis is uncertain. STUDY DESIGN: Two-by-two factorial randomized controlled trial. SETTING & PARTICIPANTS: Sixty-five patients receiving maintenance peritoneal dialysis. INTERVENTION BIA-guided volume management versus usual care and oral cholecalciferol 50,000 U weekly for 8 weeks followed by 10,000 U weekly for 44 weeks or matching placebo. OUTCOME: Change in LV mass at 1 year measured by cardiac magnetic resonance imaging. RESULTS: Total body water decreased by 0.9 + 2.4 (SD) L in the BIA group compared with a 1.5 ± 3.4 L increase in the usual care group (adjusted between-group difference -2.4 [95% CI, -4.1 to -0.68] L, P = 0.01). LV mass increased by 1.3 ± 14.3 g in the BIA group and decreased by 2.4 ± 37.7 g in the usual care group (between-group difference +2.2 [95% CI, -13.9 to 18.3] g, P = 0.8). Serum 25-hydroxyvitamin D concentration increased by a mean of 17.2 ± 30.8 nmol/L in the cholecalciferol group and declined by 8.2 ± 24.3 nmol/L in the placebo group (between-group difference 28.3 [95% CI, 17.2-39.4] nmol/L, P < 0.001). LV mass decreased by 3.0 ± 28.1 g in the cholecalciferol group and increased by 2.0 ± 31.2 g in the placebo group (between-group difference -4.5 [95% CI, -20.4 to 11.5] g, P = 0.6). LIMITATIONS: Relatively small sample size with larger than expected variation in change in LV mass. CONCLUSIONS: BIA-guided volume management had a modest impact on volume status with no effect on the change in LV mass. Vitamin D supplementation increased serum vitamin D concentration but had no effect on LV mass. FUNDING: Unrestricted Baxter International extramural grant and the Kidney Foundation of Canada. TRIAL REGISTRATION Registered at ClinicalTrials.gov with study number NCT01045980.