EFFICACY OF HYPOCALORIC TOTAL PARENTERAL-NUTRITION IN HOSPITALIZED OBESE PATIENTS - A PROSPECTIVE, DOUBLE-BLIND RANDOMIZED TRIAL

Obesity is a major health problem in the United States today. Traditionally, management of obese hospitalized patients has not differed from that of normal-weight patients, with calorie and protein needs based on current body weight and weight loss postponed until the acute illness has subsided. This study was undertaken to determine whether obese hospitalized patients (>130% ideal body weight) requiring total parenteral nutrition and given hypocaloric (HC) feedings with adequate protein intake could achieve nitrogen balance comparable with that of controls (C) given isonitrogenous nonnocaloric formulas. Sixteen obese patients (HC = 9, C = 7) were randomized to either HC (50% resting metabolic energy expenditure, plus protein; calories:nitrogen = 75:1) or C (100% resting metabolic energy expenditure, plus protein; calories:nitrogen = 150:1) formulas. Resting metabolic energy expenditure was determined by indirect calorimetry on day 0 and weekly, and nitrogen balance was determined daily. The two groups were similar in Harris-Benedict predicted energy expenditure and metabolic energy expenditure, initial and final serum albumin, total iron-binding capacity, and weight loss. Total daily calorie and nonprotein calorie intake per Kilogram body weight were 14 +/- 4.1 (HC) vs 25 +/- 4 (C) and 7 +/-1.9 (HC) vs 20 +/- 3 (C), respectively. Protein intake was 1.23 +/- 0.4 (HC) vs 1.31 +/- 0.2 (C) g/kg per day. Initial respiratory quotients were similar and consistent with fasting (HC = 0.7 +/- 0.09 vs C = 0.66 +/- 0.09); final respiratory quotients in C patients reflected mixed fuel use (C = 0.82 +/- 0.11 vs HC = 0.7 +/- 0.12). Mean net nitrogen balance was similar (HC = 1.3 +/- 3.6 g of nitrogen per day compared with C = 2.8 +/- 6.9 g/d). Eight of nine HC patients achieved positive nitrogen balance as did six of seven C patients. Duration of treatment averaged 9.6 +/- 3.0 days. These data indicate that HC feedings can be effectively administered to mildly-to-moderately stressed hospitalized obese patients and can achieve nitrogen balance comparable with that of patients given conventional total parenteral nutrition formulas.