Effects of feeding on albumin synthesis in hypoalbuminemic hemodialysis patients

Abstract

Background. Hypoalbuminemia is a powerful predictor of morbidity and mortality in hemodialysis (HD) patients and results from a reduction in albumin synthesis. It is not known if this is associated with any impairment of the normal response to feeding. Methods. Protein turnover and albumin synthesis were measured in the fasting and fed state using a primed constant infusion of L-[1-13C]leucine in seven hypoalbuminemic (albumin ≤ 36 g/L) HD patients (HHD), seven normoalbuminemic (albumin ≥ 40 g/L) HD patients (NHD) and nine age-matched normal controls. Results. The increase in albumin synthesis on feeding was impaired in HHD patients (fasting 15.0 ± 1.5 vs. fed 17.7 ± 2.9%, P = NS) compared to NHD (fasting 13.7 ± 0.9 vs. fed 17.4 ± 1.0%, P < 0.05) and controls (fasting 12.9 ± 0.6 vs. fed 15.2 ± 0.6%, P < 0.05). In addition, body mass index and percent body fat were significantly (P < 0.05) lower in HHD (20.8 ± 1.3 kg/m2, 23.4 ± 2.0%) than NHD (26.7 ± 1.3 kg/m2, 33.1 ± 3.2%) or controls (26.2 ± 1.1 kg/m2, 32.6 ± 1.8%). There was no difference in dietary protein or energy intake in the three groups. Conclusions. There are differences of body composition and protein metabolism in HHD patients that may be related to an impaired metabolic response to feeding.