Increased energy intake in hip fracture patients affects nutritional biochemical markers.

BACKGROUND AND AIMS: We have previously shown that nutritional guidelines decreased the incidence of pressure ulcers in hip fracture patients. In the present study, we evaluate whether the nutritional biochemical markers S-IGF-1 (Insulin-like Growth Factor 1), S-Transthyretin and S-Albumin are affected by patients' energy intake, and whether the markers are useful as predictors of postoperative complications. MATERIAL AND METHODS: Quasi-experimental design, with one intervention and one control group, as well as pre- and post-study measurements. Eighty-eight hip fracture patients were included: 42 in the control group and 46 in the intervention group. The control group received regular nutritional support pre- and postoperatively, while the intervention group received nutritional support that followed new, improved clinical guidelines from admission to five days postoperatively. S-Albumin, S-Transthyretin, C-Reactive Protein (S-CRP) and S-IGF-1 were analysed at admission and five days postoperatively as well as complications like pressure ulcer and infection. RESULTS: The intervention group had a significantly higher energy intake; for example, 1636 kcal versus 852 kcal postoperative day 1. S-IGF-1 levels decreased significantly in the control group, while no decrease in the intervention group. S-Albumin and S-Transthyretin decreased and S-CRP increased significantly in both groups, indicating that those markers were not affected short-term by a high-energy intake. There was no correlation between short-term post-operative complications and S-IGF-1, S-Transthyretin or S-Albumin at admission. CONCLUSION: The results of our study showed that S-IGF-1 can be used as a short-term nutritional biochemical marker, as it was affected by a five-day high-energy regimen. However, neither S-IGF-1, S-Transthyretin or S-Albumin were useful in predicting postoperative complications within five days postoperatively.

Inverse relationship between protein intake and plasma free amino acids in healthy men at physical exercise.

The effect of a "normal" (n = 8) and "high" (n = 6) protein intake (1 and 2.5 g x kg(-1) x day(-1), respectively) and of exercise on plasma amino acid (AA) concentrations, insulin, and glucagon concentrations was followed throughout a continuous 24-h period in adult male subjects at energy balance after six days on a standardized diet and exercise program. Subjects were fasting from 2100 on day 6 to 1200 on day 7 and then fed 10 identical meals hourly until 2100. Physical exercise was performed (46% maximal oxygen uptake) between 0830 and 1000 (fasting) and in a fed state (1600-1730) on each day. The normal-protein group showed fasting plasma AA concentrations that were higher (P < 0.05) than those for the high-protein group, except for leucine, methionine, and tyrosine. Glutamine, glycine, alanine, taurine, and threonine concentrations were distinctly higher ( approximately 30% or greater) throughout the 24-h period in subjects consuming the normal- vs. the high-protein diets. Exercise appeared to increase, although not profoundly, the plasma concentrations of amino acids except for glutamate, histidine, ornithine, and tryptophan. The profound diet-related differences in plasma AA concentrations are only partially explained by differences in the renal clearance of the amino acids. We speculate on the possible metabolic basis for these findings.