The hemodialysis (HD) procedure has been implicated as a potential catabolic factor predisposing the chronic HD (CHD) patients to protein calorie malnutrition. To assess the potential effects of HD on protein and energy metabolism, we studied 11 CHD patients 2 h before, during, and 2 h after HD by use of primed constant infusion of L-[1-13C]leucine and L-[ring-2H5]phenylalanine. Our results showed that HD led to increased whole body (10%) and muscle protein (133%) proteolysis. Simultaneously, whole body protein synthesis did not change, and forearm synthesis increased (120%). The net result was increased net whole body protein loss (96%) and net forearm protein loss (164%). During the 2-h post-HD period, the muscle protein breakdown trended toward baseline, whereas whole body protein breakdown increased further. Substrate oxidation during the post-HD was significantly altered, with diminished carbohydrate and accelerated lipid and amino acid oxidation. These data demonstrate that hemodialysis is an overall catabolic event, decreasing the circulating amino acids, accelerating rates of whole body and muscle proteolysis, stimulating muscle release of amino acids, and elevating net whole body and muscle protein loss.

We conclude that the presence of diabetes mellitus is the most significant independent predictor of LBM loss in renal replacement therapy patients, providing a potential explanation as to why ESRD patients with diabetes mellitus are more prone to muscle wasting.

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The nutritional status of CHD patients predicts mortality independent of concomitant presence or absence of inflammatory response. Prevention of, and timely intervention to treat uremic malnutrition by suitable means are necessary independent of the presence and/or therapy of inflammation in terms of improving clinical outcomes in CHD patients.

Objective-We tested the hypothesis that long-term resistance exercise combined with intradialytic oral nutrition (IDON) supplementation will improve markers of muscle mass and strength further compared to IDON alone in chronic hemodialysis (CHD) patients. Design-Randomized controlled trial.Setting-Outpatient Dialysis Unit at an academic center.Main outcome measure-Lean body mass (LBM). Muscle strength and other nutritional parameters were measured as secondary outcomes.Patients-Thirty-two participants (age 43±13 yrs, 21 male) on CHD Design-Subjects were randomly assigned to IDON plus resistance exercise (NS+EX) or IDON (NS) alone for 6 months. IDON consisted of a lactose-free formula consisting of protein, carbohydrate and fat. Three sets of 12 repetitions of leg-press were completed prior to each dialysis session in the NS+EX arm.Results-22 out of 32 participants completed the 6-month intervention. There were no statistically significant differences between the study interventions with respect to changes in LBM and body weight when comparing NS+EX to NS. There were also no statistically significant differences in any of the secondary outcomes measured in the study. Body weight (80.3±16.6 kg, 81.1±17.5 kg and 80.9±18.2 kg at baseline, month 3 and month 6, respectively, P=0.02) and 1-Repetition Maximum (468±148 lb, 535±144 lb, 552±142 lb, respectively, P=0.001) increased statistically significantly during the study for all patients combined.Conclusion-This study did not show further benefits of additional resistance exercise on longterm somatic protein accretion above and beyond nutritional supplementation alone. When both treatments groups were combined, body weight and muscle strength improved during the study.