Resting energy expenditure in asymptomatic HIV-infected females

The purpose of this study was to investigate whether resting energy expenditure (REE) is elevated in early, asymptomatic human immunodeficiency virus (HIV)-infected females and to study the contribution of a cytokine, tumor necrosis factor-alpha (TNF-alpha), to hypermetabolism. Cross-sectional comparison of REE in asymptomatic HIV+ females and a control group matched for age, body mass index (BMI), and fat-free mass (FFM). Twenty-six females aged 35 +/- 7 years (10 HIV+ [mean CD4+ T cell count 636/mm3] and 16 healthy controls) participated in this study. REE was measured by indirect calorimeter using a Deltatrac ventilated hood with a continuous rate of 40 L/min for 30 minutes after a 40-minute equilibrium period. All tests were performed after a 12-hour overnight fast. Twenty-four-hour urinary nitrogen was calculated to correct for respiratory quotient. Body composition was measured by bioelectrical impedance (BioAnalogics, Beaverton, OR). TNF-alpha was measured by ELISA (R & D Systems, Minneapolis, MN). Absolute REE was 17% higher (1755 kcal/kg +/- 410 versus 1497 kcal/kg +/- 197) in the HIV+ group compared with the control group (p < 0.05). REE remained significantly higher in the HIV+ group when REE was adjusted for body composition differences (p = 0.04). Results revealed a 23% higher level of TNF-alpha in the HIV+ subjects (p < 0.01); however, only a weak correlation existed between TNF-alpha and REE (r = .352). This study documented that hypermetabolism and elevated TNF-alpha exist in HIV+ females in the early stages of disease.     

Resting energy expenditure is not increased in mildly hyperglycaemic obese diabetic patients

Resting energy expenditure (REE) is believed to be increased in type 2 diabetes, an increase that is associated with deteriorating glucose tolerance during its development. Meanwhile, insulin resistance, a state linked to obesity and observed in all type 2 diabetic patients, is associated with reduced REE. Our aim was to compare REE in obese patients with and without diabetes. REE, body composition (total body water, density, percentage fat and fat-free mass: 3-compartment model) and metabolic control were assessed in fifty obese Caucasian patients with diabetes (glycated haemoglobin level 7.6 (SD 1.5) %) and fifty obese patients who were non-diabetic. Despite being more overweight and younger, obese non-diabetic patients had an absolute REE (7.73 (SD 1.44) v. 8.12 (SD 1.37) MJ; P=0.17) and percentage fat-free mass similar to those of obese diabetic patients. Even when adjusted for differences in body composition, REE remained similar in both groups. Furthermore, REE (absolute and adjusted) was unaffected by both glucose level and control (glycated haemoglobin), with fat-free mass being the only determinant of REE. We conclude that REE is not necessarily increased by the presence of diabetes in obese people.     

Resting energy expenditure in injured, septic, and malnourished adult patients on intravenous diets

Energy expenditures of 237 adult patients and 37 normal subjects receiving all nutrition intravenously were analysed retrospectively. Patients were classified as nutritionally depleted (67), post-operative (96), injured (43), or septic/depleted (31). Groups were further divided into those receiving either: (1) only 5% dextrose (D5W); (2) hypocaloric regimens including glucose and amino-acids; and (3) eucaloric or hypercaloric total parenteral nutrition (TPN) which also included fat. Resting energy expenditures (REE) of normal subjects on D5W were only 85% of predicted basal values based on either the Aub-Du Bois or Harris-Benedict equations. During D5W infusions, increases for the patient groups, above these values for normal subjects, varied depending on whether they were based on absolute values or ratios to predicted values. They were: (1) 1-11% for depleted; 1-21% for post-operative; 28-30% for injured; and 18-30% for septic/depleted patients. The average increase in REE with TPN was 10%. Variability within the patient groups was high, reducing the utility of these values as a basis for estimating energy requirements of patients needing artificial nutrition. Coefficients of variation averaged 15% across patient groups when the data were expressed in kJ/kg, and were reduced only slightly, to 12%, when data were expressed as ratios to predicted values. Thus, 1 3 of the patients would differ by more than 12% from mean values, and 1 out of 20 by more than 24%. Properly performed measurements of individual energy expenditure are therefore superior to values predicted from equations or average values previously obtained from patient groups and should be used wherever possible, particularly in the very sick.     

Resting energy expenditure in cancer patients.

In this review, we provide evidence based on our studies, for zinc deficiency and cell mediated immune disorders, and the effects of protein and zinc status on clinical morbidities in patients with head and neck cancer. We investigated subjects with newly diagnosed squamous cell carcinoma of the oral cavity, oropharynx, larynx, and hypopharynx. Patients with metastatic disease and with severe co-morbidity were excluded. Nutritional assessment included dietary history, body composition, and prognostic nutritional index (PNI) determination. Zinc status was determined by zinc assay in plasma, lymphocytes, and granulocytes. Pretreatment zinc status and nutritional status were correlated with clinical outcomes in 47 patients. Assessment of immune functions included production of TH1 and TH2 cytokines, T cell subpopulations and cutaneous delayed hypersensitivity reaction to common antigens.

At baseline approximately 50% of our subjects were zinc-deficient based on cellular zinc criteria and had decreased production of TH1 cytokines but not TH2 cytokines, decreased NK cell lytic activity and decreased proportion of CD4+ CD45RA+ cells in the peripheral blood. The tumor size and overall stage of the disease correlated with baseline zinc status but not with PNI, alcohol intake, or smoking. Zinc deficiency was associated with increased unplanned hospitalizations. The disease-free interval was highest for the group which had both zinc sufficient and nutrition sufficient status.

Zinc deficiency and cell mediated immune dysfunctions were frequently present in patients with head and neck cancer when seen initially. Zinc deficiency resulted in an imbalance of TH1 and TH2 functions. Zinc deficiency was associated with increased tumor size, overall stage of the cancer and increased unplanned hospitalizations. These observations have broad implications in the management of patients with head and neck cancer.     

恶性肿瘤患者静息能量代谢研究现状

能量代谢可以反映人体代谢基本情况,不同生理或病理时期机体代谢特征不同.恶性肿瘤负荷状态下,多数患者处于高能耗状态,但也有部分患者静息能量代谢无明显变化,这种改变可能与肿瘤的类型、病理分期、治疗手段及实验方法等因素密切相关.治疗效果对肿瘤患者静息能量消耗可产生不同影响:治疗有效时,患者静息能量消耗可恢复至正常;治疗无效时,患者静息能量代谢无改善甚至能耗量增加.恶性肿瘤患者能量代谢异常的机制可能与机体营养物质代谢异常及相关细胞因子调控有关.

Abstract：

Energy metabolism varies in different periods during the lifetime or in different pathological states. Resting energy expenditure (REE) may increase in some patients with malignant tumors, but may also show no significant difference when compared with healthy people or patients with benign tumors. The alteration of REE may be related to tumor site, pathologic stage, methods of treatment, and/or laboratory tests. The efficacy of a certain therapy may also affect REE in patients with malignant tumors: when a therapy is effective, the value of REE can return normal; however, when the treatment fails, REE will not be improved or become even higher.Mechanism governing the abnormalities of REE in patients with malignant tumors may be associated with the abnormal nutrition metabolism and the regulations of relevant cytokines.     

Resting energy expenditure in patients with alcoholic hepatitis

Patients with alcoholic hepatitis are typically malnourished. A hypermetabolic state would explain, at least in part, the muscle wasting observed in these patients. However, data on hypermetabolism in liver disease are limited and conflicting. In this study, we evaluated measured energy expenditure (MEE) vs predicted energy expenditure (PEE), and MEE in relation to urinary creatinine excretion in 20 patients with moderate and severe alcoholic hepatitis, and 20 controls. Patients with alcoholic hepatitis had depressed creatinine height index (moderate 66%, severe 78%) demonstrating muscle depletion. Patients with alcoholic hepatitis also had depressed mean serum albumin concentrations, the moderate group 2.6 g/dl and the severe group 2.0 g/dl. The mean values for measured energy expenditure in moderate alcoholic hepatitis patients, severe alcoholic hepatitis patients, and the control group were: 1556 kcal, 1878 kcal, and 1943 kcal, respectively. The mean measured energy expenditures per g of creatinine for the same groups were: 1520 kcal, 1813 kcal, and 1043 kcal, respectively. The mean measured energy expenditure/predicted energy expenditure ratio was not increased in alcoholic hepatitis patients compared to controls. However, when related to urinary creatinine excretion, the alcoholic hepatitis patients had a mean measured energy expenditure that was 55% higher than controls. In conclusion, whereas the measured energy expenditure to predicted energy expenditure ratio was not elevated in alcoholic hepatitis patients compared to controls, the measured energy expenditure per gram of creatinine was significantly increased in alcoholic hepatitis patients, supporting the concept of alcoholic hepatitis as a hypermetabolic state.     

Resting energy expenditure and its determinants in hemodialysis patients

OBJECTIVE: Chronic kidney disease is associated with several metabolic disturbances that can affect energy metabolism. As resting energy expenditure (REE) is scarcely investigated in patients on hemodialysis (HD) therapy, we aimed to evaluate the REE and its determinants in HD patients. DESIGN: Cross-sectional study. SETTING: Dialysis Unit of the Nephrology Division, Federal University of S?o Paulo, Brazil. SUBJECTS: The study included 55 patients (28 male, 41.4+/-12.6 years old) undergoing HD therapy thrice weekly for at least 2 months, and 55 healthy individuals pair matched for age and gender. Subjects underwent fasting blood tests, as well as nutritional assessment, and the REE was assessed by indirect calorimetry. RESULTS: REE of HD patients was similar to that of pair-matched controls (1379+/-272 and 1440+/-259 kcal/day, respectively), even when adjusted for fat-free mass (P=0.24). REE of HD patients correlated positively with fat-free mass (r=0.74; P<0.001) and body mass index (r=0.37; P<0.01), and negatively with dialysis adequacy (r=-0.46; P<0.001). No significant univariate correlation was found between REE and age, dialysis vintage, serum creatinine, urea, albumin, bicarbonate, parathyroid hormone (PTH) or high-sensitivity C-reactive protein (CRP). In the multiple linear regression analysis, using REE as dependent variable, the final model showed that besides the well-recognized determinants of REE such as fat-free mass and age, PTH and CRP were the independent determinants of REE in HD patients (R (2)=0.64). CONCLUSIONS: In this study, the REE of HD patients was similar to that of healthy individuals, even with the positive effect of secondary hyperparathyroidism and inflammation on REE of these patients.     

Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine

BACKGROUND: The effects of food restriction on energy metabolism have been under investigation for more than a century. Data obtained are conflicting and research has failed to provide conclusive results. OBJECTIVE: The objective of this study was to test the hypothesis that in lean subjects under normal living conditions, short-term starvation leads to an increase in serum concentrations of catecholamines and thus to an increase in resting energy expenditure. DESIGN: Resting energy expenditure, measured by indirect calorimetry, and hormone and substrate concentrations were measured in 11 healthy, lean subjects on days 1, 2, 3, and 4 of an 84-h starvation period. RESULTS: Resting energy expenditure increased significantly from 3.97 +/- 0.9 kJ/min on day 1 to 4.53 +/- 0.9 kJ/min on day 3 (P < 0.05). The increase in resting energy expenditure was associated with an increase in the norepinephrine concentration from 1716. +/- 574 pmol/L on day 1 to 3728 +/- 1636 pmol/L on day 4 (P < 0.05). Serum glucose decreased from 4.9 +/- 0.5 to 3.5 +/- 0.5 mmol/L (P < 0.05), whereas insulin did not change significantly. CONCLUSIONS: Resting energy expenditure increases in early starvation, accompanied by an increase in plasma norepinephrine. This increase in norepinephrine seems to be due to a decline in serum glucose and may be the initial signal for metabolic changes in early starvation.     

Resting energy expenditure, activity energy expenditure and total energy expenditure at age 91-96 years

There is a limited knowledge concerning energy requirements of the elderly, especially the oldest old (> 80 years). Energy requirements should be estimated from measurements of energy expenditure. For this purpose twenty-one free-living individuals (eight males, thirteen females) aged 91-96 years living in G?teborg, Sweden were studied. Total body water (TBW) measured by the doubly-labelled-water (DLW) technique was 29.5 (sd 5.4) kg in females and 35.6 (sd 4.3) kg in males. TBW measured using bioelectric impedance (BIA) was 31.6 (sd 6.4) kg in females and 42.0 (sd 7.4) kg in males. The mean difference between TBW measured by BIA and that measured by DLW was 3.54 (sd 3.6) kg (P = 0.0002). Resting metabolic rate (RMR) was measured using a ventilated-hood system and averaged 5.36 (sd 0.71) MJ/d in females (n 12) and 6.09 (sd 0.91) MJ/d in males (n 8). Difference between measured RMR and predicted BMR (n 20) was 0.015 (sd 0.86) MJ/d (NS). Total energy expenditure (TEE) measured by DLW averaged 6.3 (sd 0.81) MJ/d in females and 8.1 (sd 0.73) MJ/d in males. Activity energy expenditure (TEE - RMR), thus including diet-induced thermogenesis (DIT), averaged 0.95 (sd 0.95) MJ/d in females (n 12) and 2.02 (sd 1.13) MJ/d in males. Physical activity level (TEE/BMR) averaged 1.19 (sd 0. 19) in females and 1.36 (sd 0.21) (P = 0.08) in males. If DIT is assumed to be 10 % of the TEE, energy spent on physical activity will be very low in this population.     

Resting energy expenditure of patients with gynecologic malignancies.

To evaluate resting energy expenditure compared to predicted energy expenditure in patients with cervical or ovarian carcinoma who require specialized nutritional support.

Women with biopsy-proven cervical or ovarian carcinoma referred to the Nutrition Support Service were studied. Resting energy expenditure was measured by indirect calorimetry and compared to predicted energy expenditure (PEE) as determined by the Harris-Benedict equation for females.

Sixty one patients were studied. Patients with ovarian cancer (n = 31) had a significantly higher measured resting energy expenditure (% PEE) than patients with cervical cancer (109 +/? 18% vs. 98 +/? 16%, p < 0.02, respectively). This difference in measured resting energy expenditure between groups could not be explained by differences in the extent of disease, nutritional status, body temperature, or nutrient intake between groups. A greater proportion of patients with ovarian cancer were hypermetabolic (> 110% of predicted) in comparison to patients with cervical cancer (55% vs. 13%, p < 0.01, respectively). Measured resting energy expenditure varied between 53% and 157% of predicted for the entire population.

Ovarian cancer patients are more hypermetabolic than cervical cancer patients. The Harris-Benedict equation for females is a unreliable estimate of caloric expenditure in patients with cervical or ovarian cancer receiving specialized nutritional support.     

Resting energy expenditure in patients with chronic obstructive pulmonary disease

Resting energy expenditure (REE) was measured in 68 patients with stable chronic obstructive pulmonary disease (COPD) and in 34 weight-stable, age-matched (65 +/- 8 y; means +/- SD) healthy control subjects. Fat-free mass (FFM) determined by bioelectrical resistance explained 84% of the variation in REE in the control group but only 34% in the COPD patients. REE could not reliably be predicted from regression equations either developed in healthy subjects or in COPD patients. REE adjusted for FFM was significantly higher (P less than 0.05) in weight-losing (n = 34) than in weight-stable (n = 34) patients (6851 +/- 781 and 6495 +/- 650 kJ/d, respectively). Pulmonary function was more compromised in weight-losing patients. Adjusted REE in weight-stable patients was significantly higher (P less than 0.01) than in the healthy control group (6131 +/- 405 kJ/d). In patients with COPD, factors in addition to FFM are important determinants of REE. A disease-related increase in REE develops, which may contribute to weight loss in COPD in combination with a lack of an adaptive response to undernutrition in weight-losing patients.     

Resting and total energy expenditure in patients with inflammatory bowel disease

Patients with inflammatory bowel disease often present with weight loss. Among possible causes, an elevated energy expenditure has frequently been suggested but is the least documented. In this study resting metabolic rate (RMR) and total daily energy expenditure (TDEE) were measured in 15 outpatients with inflammatory bowel diseases and in eight healthy control subjects. Measured RMR as a percentage of that predicted from fat-free mass was not significantly different for control subjects (102 +/- 9.8%, mean +/- SD) and patients (100 +/- 13.3%). TDEE, expressed as a multiple of RMR, was 1.70 +/- 0.31 for control subjects and 1.78 +/- 0.24 for patients. When patients were subgrouped as greater than or equal to 90% or less than 90% desirable body weight, a mean increase over RMR predicted from fat-free mass was seen in the underweight patients (106 +/- 9.3%) but not in normal-weight patients (99.0 +/- 15.6%). Mean TDEE/RMR values for the patient subgroups were 1.70 +/- 0.30 and 1.88 +/- 0.08, respectively. We conclude that stable outpatients with inflammatory bowel disease have only a minimal increase in energy needs.     

Resting energy expenditure in patients with solid tumors undergoing anticancer therapy

OBJECTIVE: Few studies have investigated the resting energy expenditure (REE) of, or determined the individual predictive accuracy of prediction equations in, cancer patients undergoing anticancer therapy. This study compared the measured REE of patients with cancer undergoing anticancer therapy with (1) healthy subjects and (2) REE estimated from commonly used prediction methods. METHODS: Resting energy expenditure was measured in 18 cancer patients and 17 healthy subjects by using indirect calorimetry under standard conditions and was estimated from seven prediction methods. Fat-free mass (FFM) was measured by bioelectrical impedance analysis. Data were analyzed with regression modeling to adjust REE for FFM. Agreement between measured and predicted REE values was analyzed using the Bland-Altman approach. RESULTS: There was no significant difference in FFM-adjusted REE between cancer patients and healthy subjects (mean difference 10%). Limits of agreement were wide for all prediction methods in estimating REE as much as 40% below and up to 30% above measured REE. CONCLUSIONS: REE in cancer patients undergoing anticancer therapies does not appear to be as high as commonly thought. None of the prediction equations examined were acceptable for predicting REE of individual cancer patients or healthy subjects.     

Inflammation is associated with increased energy expenditure in patients with chronic kidney disease

BACKGROUND: Inflammation, a clinical condition observed in patients with chronic kidney disease (CKD), may be related to increased resting energy expenditure (REE). OBJECTIVES: The main objective was to investigate the relation between inflammation and REE in patients with CKD who are not undergoing dialysis. We also aimed to analyze whether a decrease in C-reactive protein (CRP) would result in a reduction in REE. DESIGN: This study enrolled 132 patients with CKD who were not undergoing dialysis, who had creatinine clearance from 5 to 65 mL.min(-1).1.73 m(-2), and who were 53.6 +/- 16 y old; 82 (62.1%) were men. Twenty-nine patients had clinical signs of infection. REE was measured by using indirect calorimetry, and inflammation was evaluated by using high-sensitivity CRP measurement. Patients were divided according to tertiles of CRP with the following intertertile ranges: first tertile, CRP < or = 0.14 mg/dL (n = 43); second tertile, CRP 0.15-0.59 mg/dL (n = 46); and third tertile, CRP > or = 0.60 mg/dL (n = 43). REE was measured before and after treatment in 10 patients who had inflammation or infection. RESULTS: After adjustment for age, sex, and lean body mass, the REE of the third (1395 kcal/d; P = 0.02) and second (1355 kcal/d; P = 0.04) tertiles was significantly higher than that of the first tertile (1286 kcal/d). In the multiple linear regression analysis (n = 132), the independent determinants of REE were lean body mass, CRP, and age (R2 = 0.55). After treatment of infection in a subgroup of 10 patients, it was observed that a significant reduction in CRP concentration was accompanied by a significant reduction of 174 +/- 165 kcal that accounted for 13% of the initial REE. CONCLUSION: This study showed that inflammation is associated with increased REE in patients with CKD.     

Resting and sleeping energy expenditure in the elderly

An estimate of a patient's energy needs is usually derived from equations, which predict energy expenditure (EE) by considering sex, age and body weight. Due to the increasing number of elderly people in a hospital population, more data on energy requirements in this age-group are needed. In this study resting energy expenditure (REE) of 40 healthy men and women, aged 51-82 years, was measured using a ventilated hood system. The results showed that some commonly used prediction equations underestimated REE by approximately 6 per cent. REE was highly correlated with fat free mass (FFM) (r = 0.88; P less than 0.001) and body weight (r = 0.85; P less than 0.001). A stepwise multiple regression analysis showed that the combination of body weight, sex and age resulted in the best prediction for REE; REE (kcal) = 1641 + 10.7 weight (kg)--9.0 age (years)--203 sex (1 = male, 2 = female) (r = 0.92). However, REE of an individual may be over- or underestimated by +/- 225 kcal (10-20 per cent) due to large between-subject variations. We suggest therefore that the energy requirements of elderly people should be measured rather than predicted. Due to small within-subject variations (including measurement error) a single REE measurement would suffice. Sleeping energy expenditure (SEE) was 7 per cent lower than REE.