Resting energy expenditure and nutritional state in patients with liver cirrhosis before and after liver transplantation

Resting energy expenditure (REE), body composition, and the biochemical parameters of liver function were measured in 26 patients before and 432 days (range: 103-1022 days) after liver transplantation (LTX). PreLTX REE was variable (mean: 1638 +/- 308 kcal/day, range: 1220-2190 kcal/day or +10 +/- 11% of Harris Benedict = HB prediction, range: -19 - +33%) and was closely related to body cell mass (r = 0.66, p < 0.0003). PostLTX REE was variable (mean: 1612 +/- 358 kcal/day, range: 1010-2490 kcal/day or +5 +/- 15% of HB prediction, range: -20 - +37%) and was closely related to body cell mass (r = 0.65, p < 0.0006). When compared with preLTX values only small changes in mean REE (-71 +/- 43 kcal/day) and a close correlation between pre and postLTX REE (r = 0.82, p < 0.001) were observed. In contrast to REE, changes in body weight were highly variable (-16.5 - +32.7 kg/year). This variance was not explained by the number of postoperative complications, pre and postLTX liver function, possible graft rejection and/or hepatitis reinfection. Pre-operative hypermetabolism (i.e. REE >+20% of HB prediction) was associated with postoperative hypermetabolism and a reduced liver function before and after LTX. Hypermetabolic patients had a poorer nutritional outcome after LTX (weight change: 0 +/- 8.4 kg/year) when compared with normometabolic controls (weight change: +5.7 +/- 7.4 kg/year; p < 0.05). There was no significant association between deviations in pre and postLTX REE and changes in body weight. When corrected for changes in the nutritional state our data provide evidence for the persistence of resting energy expenditure in liver transplant patients.     

Short-term overfeeding increases resting energy expenditure in patients with HIV lipodystrophy

BACKGROUND: HIV lipodystrophy and other lipodystrophy syndromes are characterized by extensive loss of subcutaneous adipose tissue. Lipodystrophy syndromes are also associated with increased resting energy expenditure (REE). This hypermetabolism may be an adaptive response to an inability to store triacylglycerol fuel in a normal manner. OBJECTIVE: This study was done to determine whether REE increases significantly after short-term overfeeding in patients with HIV lipodystrophy. DESIGN: REE was measured in HIV-infected patients with lipodystrophy (n = 9) and in HIV-infected (n = 10) and healthy (n = 9) controls after 3 d on a eucaloric diet and again after 3 d on a diet of similar composition but increased in calories by 50%. RESULTS: After 3 d of eucaloric feeding, REE was significantly higher in patients with HIV lipodystrophy [33.2 +/- 0.27 kcal/kg lean body mass (LBM)] than for both HIV-infected and healthy controls (29.9 +/- 0.26 and 29.6 +/- 0.27 kcal/kg LBM, respectively; P < 0.01). Furthermore, after 3 d of overfeeding, REE increased significantly in patients with HIV lipodystrophy but not in the control groups (33.2 +/- 0.27 vs 34.7 +/- 0.27 kcal/kg LBM; P < 0.01). Finally, postprandial thermogenesis did not differ among the groups after a "normal" test meal but tended to be higher in patients with HIV lipodystrophy than in healthy controls after a large test meal. CONCLUSIONS: Adaptive thermogenesis in the resting component of total daily energy expenditure and in the postprandial period may be a feature of the HIV lipodystrophy syndrome and may be due to an inability to store triacylglycerol fuel in a normal manner.     

Resting energy expenditure in cancer patients before and after gastrointestinal surgery.

The aim of this study was to assess the impact of surgical trauma on energy metabolism in cancer patients. Therefore, resting energy expenditure (REE) was determined before and after surgery in patients with newly detection gastric and colorectal cancer. Preoperative REE was measured in 104 patients. In 65 of these 104 patients REE was also measured on the seventh or eighth postoperative day. Postoperative REE was significantly higher than preoperative REE (mean +/- SD: 1471 +/- 238 vs 1376 +/- 231 kcal; p less than 0.001). After surgery 22 patients were hypermetabolic (REE greater than or equal to 115% predicted energy expenditure) compared with seven hypermetabolic patients before surgery. This hypermetabolism in the postoperative state can be explained by the administration of total parenteral nutrition (TPN), by an increased body temperature mainly as a consequence of postoperative complications and by the surgical trauma itself. Patients who received preoperative TPN (n = 12) showed a 10% increase in REE. Thirteen patients suffered from minor and major postoperative complications; postoperative REE in this group was increased by 10%. Forty patients who had undergone uncomplicated surgery showed a slight but significant increase of 3% in REE after operation. We conclude from this study that the increase in REE resulting from surgical trauma itself is modest at the seventh to eighth postoperative day. Therefore, energy requirements for patients undergoing major elective surgical stress are lower than generally presumed.     

Energy balance in elderly patients after surgery for a femoral neck fracture

To study energy and protein balances in elderly patients after surgery, spontaneous energy and protein intake and resting energy expenditure (REE) were measured in 20 elderly female patients with a femoral neck fracture (mean age 81 +/- 4, SD, range 74-87 years; weight 53 +/- 8, range 42-68 kg) during a 5-6 day period following surgery. REE, measured over 20-40 min by indirect calorimetry using a ventilated canopy, averaged 0.98 +/- 0.15 kcal/min on day 3 and decreased to 0.93 +/- 0.15 kcal/min on day 8-9 postsurgery (p less than 0.02). REE was positively correlated with body weight (r = 0.69, p less than 0.005). Mean REE extrapolated to 24 hr (24-REE) was 1283 +/- 194 kcal/day. Mean daily food energy intake measured over the 5-day follow-up period was 1097 +/- 333 kcal/day and was positively correlated with 24-REE (r = 0.50, p less than 0.05). Daily energy balance was -235 +/- 351 kcal/day on day 3 (p less than 0.01 vs zero) and -13 +/- 392 kcal/day on day 8-9 postsurgery (NS vs zero) with a mean over the study period of -185 +/- 289 kcal/day (p less than 0.01 vs zero). When an extra 100 kcal/day was allowed for the energy cost of physical activity, mean daily energy balance over the 5-day study period was calculated to be -285 +/- 289 kcal/day (p less than 0.01 vs zero). Measurements of total 24-hr urinary nitrogen (N) excretion were obtained in a subgroup of 14 patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Resting energy expenditure in patients with end-stage liver disease and in normal population

Resting energy expenditure (REE) was measured in 10 patients with end-stage liver disease (ELD) and in 31 normal controls. Basal energy expenditure (BEE) was also predicted by the Harris-Benedict equation. In order to correlate REE to lean body mass, the 24-hr urinary creatinine was measured in patients with ELD and in normal controls and expressed as kcal/g urinary creatinine. Linear regression analysis showed a statistically significant (p less than 0.0001) correlation (r = 0.72) between the REE and the 24-hr urinary creatinine in normal controls, irrespective of age and sex. Mean BEE (1580 +/- 160 vs 1575 +/- 210) and REE (1755 +/- 215 vs 1800 +/- 330) were not significantly different between patients with ELD and controls. However, the mean REE was 1900 +/- 610 kcal/g creatinine in patients with ELD and 1180 +/- 260 (p less than 0.0001) in controls. When related to lean tissue, patients with ELD had increased energy expenditure, confirming the hypermetabolic state suggested on clinical grounds. The use of urine creatinine to estimate energy expenditure may be a simple clinical technique to predict dietary energy needs in malnourished, unstressed patients. When this estimated energy expenditure/g creatinine (EEE) is compared to measured energy expenditure/g creatinine in malnourished, stressed patients, the EEE provides an index of the extent of hypermetabolism.     

DXA: potential for creating a metabolic map of organ-tissue resting energy expenditure components

OBJECTIVE: This study tested the hypothesis that tissue-organ components can be derived from DXA measurements, and in turn, resting energy expenditure (REE) can be calculated from the summed heat productions of DXA-estimated brain, skeletal muscle mass (SM), adipose tissue, bone, and residual mass (RM). RESEARCH METHODS AND PROCEDURES: Subjects were divided into five groups of adults <50 years of age. The specific metabolic rate of RM was developed in 13 Group I healthy subjects and a DXA-brain mass prediction formula in 52 Group II subjects. SM, adipose tissue, and bone models were developed based on earlier reports. The composite REE prediction model (REEp) was tested in 154 Group III subjects in whom REEp was compared with measured REE (REEm). Features of the developed model were determined in 94 normal-weight men and women (Group IV) and seven spinal cord injury patients and healthy matched controls (Group V). RESULTS: REEp and REEm in Group III were highly correlated (y = 0.85x + 233; r = 0.82, p < 0.001), and no bias was detected. Both REEm (mean +/- SD, 1,579 +/- 324 kcal/d) and REEp (1,585 +/- 316 kcal/d) were also highly correlated (r values = 0.85 to 0.98; p values < 0.001) and provided similar group values to REE estimated by the Harris-Benedict equations (1,597 +/- 279 kcal/d) and Wang's composite fat-free mass-based REE equation (1,547 +/- 248 kcal/d). New insights into the sources and distribution of REE were provided by analysis of the demonstration groups. DISCUSSION: This approach offers a new practical and educational opportunity to examine REE in subject groups using modeling strategies that reveal the magnitude and distribution of fundamental somatic heat-producing units.     

Energy expenditure in patients with multiple organ failure

We measured the level of resting energy expenditure (BEE) and its evolution in patients with multiple organ failure (MOF). We studied 30 patients requiring mechanical ventilation and sedation. REE was measured by means of a closed circuit method on days 1-5, 7, 10 and 14 after initiating the protocol. REE values between 115% and 145% of the REE calculated from the Harris-Benedict's formula were considered as moderate hypermetabolism and values above 145% as severe hypermetabolism. A predictive formula for determining caloric requirements was developed and validated in another 25 MOF patients. In the study group, 25 patients presented moderate hypermetabolism (83%) and two severe hypermetabolism(7%). Mean REE in the whole group was stable but individual patients may have had a large variability in REE. The anthropometric variables, body temperature and reason for admission predicted the REE with a coefficient of determination of 0.73, according to the model: REE= -3295 + 105.5S - 8A + 11.7 W + 7.7 H + 93.2 T + 123.1 Tr - 145.6 Su where: S = sex (male = 1, female = 0); A: age in years; W: weight in Kg; H: height in cm; T: temperature in degrees C; Tr: trauma (Tr = 1); Su: surgical (Su = 1). The reliability of the model, taken from the validation group, showed that the shrinkage was 0.8%. In conclusion, when MOF patients are sedated they present moderate hypermetabolism. Day-to-day variability of REE in the individual patients and the large variability in estimating REE with our formula preclude its clinical utility and we recommend to measure REE in MOF patients.     

Equation to estimate resting energy expenditure in adolescents with sickle cell anemia

BACKGROUND: Basal energy requirements are higher in adolescents with sickle cell anemia (SCA) than in healthy control subjects. However, no equation is available to accurately predict their energy needs. OBJECTIVE: Our objective was to develop a clinically useful equation to estimate resting energy expenditure (REE) in adolescents with SCA. DESIGN: REE and other components of total energy expenditure were measured in adolescents with SCA (n = 37) and in control subjects (n = 23) for 24 h in a whole-room indirect calorimeter. Multiple linear regression analysis was used to describe the relations of REE with independent variables such as sex, weight, height, fat-free mass, fat mass, age, and hemoglobin concentration in adolescents with SCA. The Bland-Altman comparison technique was used to compare values predicted by existing equations with measured REE values. RESULTS: Mean (+/-SD) measured REEs were 7746 +/- 974 and 6332 +/- 869 kJ/d in the male and female subjects with SCA, respectively, and these values were 16% higher than those in the healthy control subjects. Standard equations underestimated REE by 12% (P 相似文献   

Growth velocity, fat-free mass and energy intake are inversely related to viral load in HIV-infected children

The study objectives were to assess the relationships among human immunodeficiency virus (HIV) replication, energy balance, body composition and growth in children with HIV-associated growth failure (GF). Energy intake and expenditure, body composition and level of HIV RNA were measured in 16 HIV-infected children with growth failure (HIV+/GF+), defined as a 12-mo height velocity 相似文献   

Kinetics of sedimentation rate, viral load and TNF-alpha in relation to HIV co-infection in tuberculosis

The kinetics of potential surrogate markers in HIV-positive (HIV+) and HIV-negative (HIV-), smear-positive tuberculosis (Tb+) patients in Gondar, Ethiopia (n = 60) was investigated. Clinical symptoms, sputum conversion, sedimentation rate (SR), HIV viral load and serum levels of TNF-alpha were determined before and 8 weeks after treatment initiation. The co-infection rate of HIV was 45%. There were significantly higher initial levels of SR and TNF-alpha in HIV+/Tb+ patients (79 +/- 29 mm/h and 13.5 +/- 7.6 pg/ml), than in HIV-/Tb+ patients (60 +/- 23 mm/h and 6.8 +/- 5.9 pg/ml, P<0.001). In HIV-/Tb+ patients, there was a marked decrease in SR compared with co-infected patients (46% [33 +/- 24 mm/h at week 8] vs. 24% [61 +/- 27 mm/h at week 8]). The HIV viral load (4.99 [range 3.70-5.92] to 4.90 [range 3.96-5.78] log10 copies/ml from week 0 to 8) and TNF-alpha (13.5 +/- 7.6 to 12.0 +/- 6.0 pg/ml) remained high in HIV+/Tb+ patients. In Tb patients, SR was significantly increased in HIV+ compared with HIV- patients. Additionally, TNF-alpha and HIV viral load remained elevated in HIV+/Tb+ patients following treatment despite clinical improvement comparable to HIV-/Tb+ patients.     

The effect of severe undernutrition and subsequent refeeding on whole-body metabolism and protein synthesis in human subjects

BACKGROUND: To determine the consequences of severe undernutrition and refeeding on whole-body metabolism and protein synthesis. METHODS: Respiratory quotient (RQ), resting energy expenditure (REE), and whole-body protein synthesis (WBPS) were assessed in undernourished patients, with anorexia nervosa (n = 8) or with coexistent disease (n = 17). Results were compared with 17 healthy controls. Six anorexic patients and 13 disease patients consented to study after nutrition support. RESULTS: Mean body mass index was 12.46 +/- 0.53 kg/m2 in the anorexia patients and 13.81 +/- 0.40 kg/m2 in the disease patients (controls 23.71 +/- 0.72 kg/m2; p < .001). Compared with controls, RQ was similar in anorexia patients (0.85 +/- 0.05 vs 0.90 +/- 0.05) but lower in the disease patients (0.76 +/- 0.03 vs 0.90 +/- 0.05; p = .02). REE was lower in the patients (anorexia 1058 +/- 134.0 kcal/d, disease 1189 +/- 101.4 kcal/d vs 1828 +/- 89.76 kcal/d; p < .001); however, expressed as kcal/kg/d, it was higher (anorexia 32.17 +/- 4.25, disease 31.30 +/- 2.14 vs 25.07 +/- 1.00; p < .05). WBPS was lower in the patients (anorexia 140.9 +/- 10.54 g/d, disease 119.8 +/- 8.57 g/d vs 305.0 +/- 21.64 g/d; p < .001); however, when expressed as g/kg/d, the anorexia patients were similar to controls, whereas the disease patients were lower (3.11 +/- 0.24 vs 4.27 +/- 0.32; p < .05). Refeeding increased RQ in the disease patients (0.84 +/- 0.03 vs 0.76 +/- 0.03; p < .05), and normalized REE (anorexia 27.65 +/- 3.05 kcal/kg/d, disease 28.90 +/- 1.85 kcal/kg/d). WBPS increased in the disease patients (173.6 +/- 16.38 g/d vs 116.5 +/- 10.15 g/d; p < .01). CONCLUSIONS: Undernutrition is associated with increased REE (kcal/kg/d). Reduction in RQ and protein synthesis (g/kg/d) was evident in those patients with coexistent disease. Refeeding resulted in normalization of RQ, REE (kcal/kg/d), and protein synthesis (g/kg/d).     

Assessing energy expenditure in cancer patients: a pilot validation of a new wearable device

BACKGROUND: Nutrition problems are common in cancer patients and are frequently due to metabolic derangements. Thus, accurately assessing energy expenditure (EE) is important in planning adequate nutrition support. Indirect calorimetry (IC) represents the gold standard method but is not always available or applicable to all settings. The purpose of this study was to preliminary compare a new wearable device, the SenseWear armband (SWA), to IC in cancer patients. METHODS: Ten (6 M, 4 F) subjects (mean +/- SD: 56.6 +/- 13.3 years) affected by newly diagnosed acute myelogenous leukemia, undergoing induction chemotherapy, were prospectively enrolled. Resting EE (REE) was measured simultaneously by SWA and IC on admission (day 0) and at discharge (end). Total daily EE (TDEE) was determined by SWA 4 times during the stay (days 0, 7, 14, and end) and predicted values were calculated according to IC REE estimates (TDEE = IC x correction factor 1.2). RESULTS: Mean length of stay was 27.1 +/- 6.2 days. Bland-Altman plots revealed no significant differences between overall REE estimates (day 0 + end) performed by IC and SWA (mean +/- SD; 1645 +/- 282 vs 1705 +/- 278 kcal/d) and the correlation was high (r = 0.84; p < .0001). SWA TDEE showed a progressive reduction during the stay. No bias was detected between overall SWA TDEE (1799 +/- 153 kcal/d) and IC predicted TDEE (1974 +/- 176 kcal/d), but there was a wide 95% confidence interval (-672; +321 kcal/d). Moreover, the correlation between these values was significant (r = 0.68; p = .001). CONCLUSIONS: SWA seems to provide accurate and reliable estimation of REE and useful information on TDEE also in cancer patients. Its use appears promising. Validation studies on larger samples and different cancer types should be considered.     

Relationship between blood adipocytokines and resting energy expenditure in young and elderly women

It has been demonstrated in a previous study that resting energy expenditure (REE) is associated with adiponectin levels in the blood. However, body composition was not taken into consideration in that study. The purpose of the present study was to again investigate the relationship between blood adipocytokines and REE, adjusted by body composition, in both young and elderly women. REE and blood adipocytokines were measured in 115 young (age: 22.3+/-2.1 y, BMI: 21.3+/-1.9 kg/m(2)) and 71 elderly (63.4+/-6.5 y, 22.9+/- 2.3 kg/m(2)) women. Dual energy X-ray absorptiometry was used to measure percent body fat. Fat mass and fat free mass (FFM) were calculated. REE (kcal/d and kcal/kg BW/d) was lower in elderly women than in young women, but no significant difference was observed in REE, expressed as kcal/kg FFM/d, between the two groups. Although elderly women had a higher percent body fat and higher serum leptin concentrations than young women, plasma adiponectin concentrations did not differ between young and elderly women. In elderly women, REE (kcal/d) was significantly and inversely correlated with plasma adiponectin concentration (r=-0.386, p<0.001), but REE expressed per kilogram of BW or FFM was not significantly correlated. Furthermore, no significant correlation was observed between REE (kcal/d) and concentrations of plasma adiponectin or serum leptin, after adjusting for potential confounders such as body composition and hormones, in either age group. These results suggest that adipocytokines do not influence REE in adult women.     

Total and regional body composition and energy expenditure in multiple symmetric lipomatosis

AIMS: The aim of the present study was to investigate possible alterations in body composition and resting energy expenditure (REE) in type 1 multiple symmetric lipomatosis (MSL). SUBJECTS AND METHODS: Thirteen men aged from 40 to 78 years affected by type I MSL were compared with 13 healthy control subjects. Fat mass (FM) and fat-free mass (FFM) were determined by DEXA using both standard analysis and specifically for the lipomatous region. REE was measured by indirect calorimetry. RESULTS: FM was higher in MSL subjects at proximal arm level, but significantly lower at distal leg level than in controls (left 1.63+/-0.55 vs. 2.26+/-0.49 kg, P<0.05; right 1.63+/-0.53 vs. 2.40+/-0.54 kg, P<0.01). Arm FFM was similar in the two groups, while distal leg FFM was significantly lower in MSL cases (left: 7.8+/-1.3 vs. 8.7+/-0.8 kg, P<0.05; right: 8.0+/-1.5 vs. 9.2+/-0.9 kg, P<0.05). FFM strongly correlated with REE (r:0.86;P<0.001). REE, expressed as an absolute value and adjusted for FFM (1830+/-215 vs. 1675+/-120 kcal, P<0.05) was higher in MSL patients. CONCLUSION: In conclusion, MSL patients had a marked FFM and FM atrophy in the lower segments of the legs and an altered energy expenditure (hypermetabolism).     

Energy balance in relation to cancer cachexia

The aim of the current study was to determine the contribution of increased resting energy expenditure (REE) and/or decreased energy intake (EI) to the development of weight loss in gastric and colorectal (GCR) and lung cancer patients. REE was measured in 22 GCR cancer patients and 17 lung cancer patients and was compared with REE values in 40 apparently healthy controls. REE in lung cancer patients expressed per kg fat free mass (REE/FFM) was significantly increased when compared to healthy controls (33.5 +/- 5.4 and 29.6 +/- 2.9 kcal, respectively; p < 0.01). GCR cancer patients had no elevated REE compared to these healthy controls. No significant differences in EI were established between the three groups. Eight GCR cancer patients reported a decrease in food intake compared to pre-disease intake, in contrast to only one lung cancer patient. Semi-starving GCR cancer patients showed a significant weight loss (8.7 +/- 8.1%), a low respiratory quoteint (RQ) (0.76 +/- 0.04) and a high beta-hydroxybutyrate level (259 +/- 192 mumol/l), but they showed no difference in REE compared to patients with a normal EI. The current study suggests that weight loss in GCR cancer patients is initiated by decreased food intake, whereas weight loss in lung cancer patients represents a combination of an increased REE and a relatively low EI.     

Energy balance and luteal phase progesterone levels in elite adolescent aesthetic athletes

Menstrual abnormalities are associated with negative energy balance and reduced energy expenditure (REE). To examine this relationship in elite adolescent aesthetic athletes, 3 groups of females (aged 15-18 years) were studied: 10 oligo/amenorrheic athletes (OA), 11 eumenorrheic athletes (EA), and 8 non-athlete controls (C). Components of energy balance, body composition, dietary restraint, pubertal maturation, and luteal phase salivary progesterone were assessed in all groups. Both groups of athletes had a later age of menarche and lower pubertal development score compared to the non-athletes (p < or = .05). With the exception of salivary progesterone (ng/ml; OA = 0. 15 +/- 0.01 相似文献   

Accurate determination of energy needs in hospitalized patients

OBJECTIVE: To evaluate the accuracy of seven predictive equations, including the Harris-Benedict and the Mifflin equations, against measured resting energy expenditure (REE) in hospitalized patients, including patients with obesity and critical illness. DESIGN: A retrospective evaluation using the nutrition support service database of a patient cohort from a similar timeframe as those used to develop the Mifflin equations. SUBJECTS/SETTING: All patients with an ordered nutrition assessment who underwent indirect calorimetry at our institution over a 1-year period were included. INTERVENTION: Available data was applied to REE predictive equations, and results were compared to REE measurements. MAIN OUTCOME MEASURES: Accuracy was defined as predictions within 90% to 110% of the measured REE. Differences >10% or 250 kcal from REE were considered clinically unacceptable. STATISTICAL ANALYSES PERFORMED: Regression analysis was performed to identify variables that may predict accuracy. Limits-of-agreement analysis was carried out to describe the level of bias for each equation. RESULTS: A total of 395 patients, mostly white (61%) and African American (36%), were included in this analysis. Mean age+/-standard deviation was 56+/-18 years (range 16 to 92 years) in this group, and mean body mass index was 24+/-5.6 (range 13 to 53). Measured REE was 1,617+/-355 kcal/day for the entire group, 1,790+/-397 kcal/day in the obese group (n=51), and 1,730+/-402 kcal/day in the critically ill group (n=141). The most accurate prediction was the Harris-Benedict equation when a factor of 1.1 was multiplied to the equation (Harris-Benedict 1.1), but only in 61% of all the patients, with significant under- and over-predictions. In the patients with obesity, the Harris-Benedict equation using actual weight was most accurate, but only in 62% of patients; and in the critically ill patients the Harris-Benedict 1.1 was most accurate, but only in 55% of patients. The bias was also lowest with Harris-Benedict 1.1 (mean error -9 kcal/day, range +403 to -421 kcal/day); but errors across all equations were clinically unacceptable. CONCLUSIONS: No equation accurately predicted REE in most hospitalized patients. Without a reliable predictive equation, only indirect calorimetry will provide accurate assessment of energy needs. Although indirect calorimetry is considered the standard for assessing REE in hospitalized patients, several predictive equations are commonly used in practice. Their accuracy in hospitalized patients has been questioned. This study evaluated several of these equations, and found that even the most accurate equation (the Harris-Benedict 1.1) was inaccurate in 39% of patients and had an unacceptably high error. Without knowing which patient's REE is being accurately predicted, indirect calorimetry may still be necessary in difficult to manage hospitalized patients.     

Effects of exercise training on resting energy expenditure during caloric restriction

Resting energy expenditure (REE), maximum oxygen uptake (VO2max), and body composition were measured in seven moderately obese women during 9 wk of dietary restriction (800 kcal/d). During weeks 4-6, subjects underwent exercise training (30 min cycling/d, 5 d/wk, at 70% VO2max). The first 3 wk of caloric restriction decreased REE by 13% (from 1437 +/- 76 to 1254 +/- 66 kcal/24 h, means +/- SEM, p less than 0.05). Exercise training increased VO2max (from 1717 +/- 108 to 1960 +/- 120 mL/min, means +/- SEM, p less than 0.05) but did not elevate the dietary-depressed REE (from 1254 +/- 66 to 1262 +/- 62 kcal/24 h). The greatest decrease in body fat (3.7 +/- 0.4 kg) occurred during exercise training, resulting in a small apparent increase in REE when expressed per kilogram total body weight. However, expressed per unit lean body mass, REE remained suppressed throughout the period of caloric restriction. We conclude that exercise training of sufficient intensity to substantially increase VO2max does not reverse the dietary-induced depression of REE.     

Resting energy expenditure and plasma leptin levels in anorexia nervosa during acute refeeding

OBJECTIVE: To examine changes in plasma leptin levels and resting energy expenditure (REE) during short-term refeeding of patients with anorexia nervosa (AN). METHOD: This was a longitudinal study of 21 women meeting the DSM-IV criteria for AN who were admitted to the hospital for renutrition. Height, weight, percent body fat (assessed by skin fold thickness), REE (measured by indirect calorimetry), and circulating plasma leptin concentration were assessed at the time of admission and 7 days later. RESULTS: Over the course of 1 week of refeeding, body mass index (BMI) increased 0.75 +/- 0.15 kg/m(2) (p <.0001), body fat increased 0.9 +/- 0.2% (p <.0001), and REE increased 107 +/- 33 kcal/24 hr (p =.0037). The change in mean leptin levels was not statistically significant (0.45 +/- 0.44 ng/ml; p =.32). DISCUSSION: Leptin is unlikely responsible for the increase in REE observed with short-term refeeding.     

Effects of race, cigarette smoking, and use of contraceptive medications on resting energy expenditure in young women

The prevalence of obesity is higher in Black women than in White women (JAMA 1994;272:205-11; Arch Pediatr Adolesc Med 1995;149:1085-91). Although it has been shown that Black women have a lower resting energy expenditure (REE), factors affecting REE remain unclear. This 1996-1997 study in Cincinnati, Ohio, assessed racial differences in REE and their determinants in a biracial cohort of 152 healthy young women aged 18-21 years. Two indirect calorimetric measurements were obtained during two overnight hospital admissions 10-14 days apart. Body composition was measured by using dual-energy x-ray absorptiometry. Mean REE (adjusted for body composition, smoking, and contraceptive medication use) was significantly (p = 0.04) lower by 71 kcal/day in Black women (1,453 (standard error, 21) kcal/day) than in White women (1,524 (standard error, 19) kcal/day). Smoking was associated with a REE that was 68 kcal/day higher for both groups (p = 0.03). A trend (p = 0.07) toward increased REE (by 46 kcal/day) was found with contraceptive medication use. In conclusion, young Black women had a significantly lower REE than did White women. Cigarette smoking significantly increased REE. The apparent presence of a more parsimonious energy metabolism in Black women suggests that maintenance of energy homeostasis requires particular vigilance in this high-risk population.