Body composition in home haemodialysis versus conventional haemodialysis: a cross-sectional, matched, comparative study

Abstract

Background: Nutritional status predicts outcome in dialysis populations. Increased dialysis time and/or frequency reportedly improves nutritional status. We examined the impact of more intensive dialysis on body composition.

Methods: A cross-sectional, matched study comparing home haemodialysis (HHD) patients (>15 h/week, n = 28) and conventional haemodialysis (CHD) patients (<15 h/ week, n = 28), matched for age, sex, length of time on dialysis and diabetes, was performed. We measured total body protein (TBP) by in vivo neutron activation, total body fat (TBF) and skeletal muscle mass (SKMM) by dual-energy x-ray absorptiometry (DEXA) and biochemical and inflammatory parameters. Visceral (VFA) and subcutaneous fat areas (SFA) were determined from computed tomography.

Results: There was no significant difference in TBP (10.2 +/- 1.9 kg CHD versus 10.8 +/- 1.8 kg HHD, P = 0.18) or SKMM (25.6 +/- 5.6 kg CHD versus 26.2 +/- 4.2 kg HHD). TBF was not different (27.7 +/- 10.7 kg CHD versus 27.8 +/- 16.0 kg HHD), although the HHD group had greater VFA (182.0 +/- 105.6 cm(2) versus 173.8 +/- 90.1 cm(2)) and lower SFA (306.7 +/- 176.4 cm(2) versus 309.7 +/- 138.1 cm(2)), the difference was not statistically significant. Albumin concentrations were significantly increased in the HHD group (37.5 +/- 3.56 g/L versus 35.18 +/- 4.11 g/L, P = 0.03), whilst phosphate concentrations (1.57 +/- 0.41 mmol/LHHD versus 1.92 +/- 0.62 mmol/ LCHD, P = 0.02) and inflammatory parameters were lower. There was a positive relationship between hours of dialysis and TBP (beta = 0.08; P = 0.03).

Conclusion: Surrogate nutritional markers and inflammatory parameters improved with more intensive dialysis, but this was not reflected by improved body composition. Further prospective studies are required to confirm whether more intensive dialysis affects body composition, and whether this impacts on metabolic risk and clinical outcome.