Selenate-supplemented nutritional formula increases plasma selenium in hemodialysis patients

Abstract

Objective: The purpose of this study was to determine the short-term effect of feeding selenium-supplemented formulas on the selenium status of end-stage renal disease patients on hemodialysis. Design and setting: The prospective, randomized, single-blind study of parallel design was conducted at three hemodialysis clinics. Patients: A total of 79 hemodialysis patients were randomly assigned into one of three groups. Intervention: Liquid nutritional formula supplemented with either selenite (28 μg Se/8 oz, n = 26), selenate (28 μg Se/8 oz, n = 26), or nonfortified (7 μg Se/8 oz, n = 27) was fed to hemodialysis patients as their sole source of nutrition for 14 days. Main outcome measure: Plasma and red blood cell (RBC) selenium and glutathione peroxidase (GPX) activities were measured in predialysis blood both before (day 1) and after (day 8) a 7-day baseline period, and after subjects received the formula as the sole source of nutrition (approximately 35 kcal/kg/d) for 14 days (day 22). Results: Selenium intake (Mean ± SEM, μg/d) was 134 ± 9, 140 ± 9, and 35 ± 2 for patients receiving selenite-, selenate-, or non-supplemented formula, respectively. On day 22, plasma selenium (μmol/L) was greater ( P < .032) in the selenate-supplemented group (1.5 ± 0.1) compared with the nonsupplemented group (1.2 ± 0.1), but not compared with the selenite-supplemented group (1.4 ± 0.1). Plasma GPX activity was 44% to 60% that of healthy controls and not different among groups. RBC selenium and GPX activities were within the normal range and were not different among groups. Conclusion: The results of this study indicate that a liquid formula supplemented with selenium as selenate is successful at maintaining selenium concentrations within normal range, as well as significantly increasing plasma selenium levels compared with nonsupplementation.