[Effect of hypocaloric nutritional support on protein metabolism in patients with gastric cancer after radical gastrectomy]

Abstract

In this study, 17 patients with advanced gastric cancer were randomized into 3 groups to investigate the changes of protein metabolism-and the nitrogen sparing effect of both hypo-and hypercaloric nutrition after radical gastrectomy. Group 1, as control (n = 6) receiving 14 +/- 1.2 kcal/kg/d with no protein; Group 2, as hypercaloric (n = 6) receiving 32 +/- 3.8 kcal/kg/d(by Harris Benedict Equation) and 1.23 g/kg/d of protein; Group 3, hypocaloric (n = 5) with less than 50% of calories and the same amount of protein as in Group 2. 15N-glycine was used to evaluate the protein synthesis and breakdown rates, and the nitrogen balance, nitrogen retention, plasma proteins (albumin, fibronectin), protein catabolic parameters such as nitrogen, creatinine, 3-MH excretion in the urine, and CPK in serum were evaluated. It was found that although in all three groups there was significant protein catabolism after surgery, there was significant reduction of negative nitrogen balance in Group 2 (-2.7 +/- 2.1 g/d) and Group 3 (-2.8 +/- 3.1 g/d) as compared with Group 1 (-9.6 +/- 1.73 g/d). Nitrogen retention rate was 75 +/- 4.5% in Group 3 and 78.6 +/- 3.9% in Group 2. Postoperative fibronectin concentration in Group 1 was also statistically different from Group 2 or Group 3. Protein synthesis was increased by 57.7% and 60.6%, and breakdown by 14.9% and 18.9% respectively in Group 2 and 3. It was concluded that hypocaloric nutrition was as effective as hypercaloric support in this situation.