Biomedical subjects

K R Westerterp

Publications and source records attributed to K R Westerterp.

At least 91 records · Page 5Linked to original sources

PubMed1997

The effect of fat composition of the diet on energy metabolism.

Animal and human studies show that polyunsaturated fatty acids (P) are oxidized more rapidly than saturated fatty acids (S). There are indications that diets high in P/S ratio result in a relatively high resting metabolic rate (RMR) and high diet induced thermogenesis (DIT). However, studies with human subjects are limited. The effect of dietary fatty acid composition on energy metabolism was studied in 6 male subjects, age 25-48 y. Two diets were supplied, each over a period of 14 days, in a randomized crossover design with a washout period of 14 days. P/S ratios of the diets were 0.19 and 1.67. On day 14, RMR was determined in the morning in fasting state by means of indirect calorimetry (ventilated hood), followed by a 4 hour measurement of the DIT after consumption of a standardized meal of 3.3 MJ with the same fatty acid composition as during the dietary period. The meal contained 46, 37, and 17 % energy as fat, carbohydrate, and protein, respectively. RMR after the period with the high P/S diet was significantly higher than after the period of the low P/S diet. The average difference (+/- SD) was 0.17 +/- 0.14 kJ/min or 3.6 +/- 2.7 % of RMR. The DIT was also higher in all subjects during a breakfast with a high P/S ratio. The average difference was 0.29 +/- 0.16 kJ/min, which is 22.1 +/- 12.6 % of DIT. The study showed that a prolonged food intake of a diet with a high P/S ratio results in a relatively high RMR and DIT. These results indicate the importance of dietary lipid profile in the treatment of obesity.

Adult↗

PubMed1997

The adaptation of nutrient oxidation to nutrient intake on a high-fat diet.

Intervention studies have shown that the adaptation of fat oxidation to fat intake, when changing the dietary fat content, is not abrupt. This study was conducted to measure the time course of adaptation of oxidation rates to increases in the fat content of the diet, when feeding subjects at energy balance. Twelve healthy, non-obese males and females (age: 26 +/- 2, BMI: 21.4 +/- 0.5, habitual fat intake: 29 +/- 1% energy) consumed a low-fat diet for 6 days (days 1-6) followed by a high-fat diet for 7 days (day 7-13). Days 5-9 and day 13 were spent in a respiration chamber. After adjusting energy intake to 24h energy expenditure on day 5, subjects were in energy balance (range -0.15 to +0.23 kJ/day) on days 6-9 and day 13. Fat balance was zero on day 6 but became positive after changing to the high-fat diet (1.06 +/- 0.15, 0.75 +/- 0.15, and 0.55 +/- 0.14 MJ/day for days 7, 8, and 9 respectively, p. < 0.05), reaching a new balance on day 13, 7 days afterwards. Thus, in case of energy balance, lean subjects are capable of adjusting fat oxidation to fat intake within 7 days, when dietary fat content is increased.

Acclimatization↗

PubMed1997

Total energy expenditure in infants with bronchopulmonary dysplasia is associated with respiratory status.

UNLABELLED: Growth failure is a well-known problem in infants with bronchopulmonary dysplasia (BPD). We studied BPD infants' total daily energy expenditure (Ee), nutritional balance, and growth in relation to their past and current clinical status. Applying the doubly labelled water technique, Ee was measured in nine preterm infants with BPD receiving supplemental oxygen (postnatal age 61 +/- 13 days) and nine matched controls (36 +/- 21 days) during a 6-day period. Energy and protein balance, past and present respiratory status, and growth were assessed as well. The results show that Ee was higher in the BPD infants compared to controls (73 +/- 9 vs 63 +/- 8 kcal/kg/day, P < 0.05), but their faecal energy loss was lower (P < 0.01). Weight gain, energy intake, energy cost of growth, protein retention, and physical activity were not different. The respiratory frequency (RR) in the BPD infants was elevated in comparison with controls (P < 0.01). Within the BPD group, RR was positively correlated with energy expenditure (regression equation: Ee [kcal/kg/day] = 26.3 + 0.71*RR [min-1]; r2 = 0.82, P < 0.001), and was the single most significant determinant of Ee. CONCLUSION: Total energy expenditure in BPD infants is elevated and is strongly associated with their respiratory status. These findings could be of practical value for the nutritional management in infants with severe BPD.

Anthropometry↗

PubMed1997

Effect of diet composition on leptin concentration in lean subjects.

The recently discovered leptin is thought to be a satiety signal regulating food intake. In mice, it has been shown that on a high-fat diet leptin concentration increases, but the increase was explained by increased fat mass. It is yet unknown whether leptin is influenced by other nutritional factors. Here, leptin levels were measured in human volunteers on a high-fat diet, while maintaining energy balance. Twelve healthy, non-obese males and females (age, 26 +/- 2 years; 21.4 +/- 0.5 body mass index, habitual fat intake, 29 +/- 1 energy % [en%]) consumed a high-fat diet (60 en% fat) for 7 days (days 1 to 7). Subjects were in energy balance (range, -0.15 to +0.23 MJ/d) as measured in a respiration chamber on days 1 to 3 and 7. Fasting baseline plasma leptin concentrations correlated with body fat percentage (R2 = .64, P < .005). On average, no changes in leptin concentration on the high-fat diet were observed. However, on an individual basis, changes in leptin concentrations in response to the high-fat diet correlated with changes in insulin concentrations. In conclusion, in the case of energy balance, short-term changes in diet composition have no effect on fasting leptin concentration in lean subjects.

Blood Glucose↗

PubMed1997

Assessment of fat-mass loss during weight reduction in obese women.

Methods for assessing body fat mass (FM) loss were compared in 32 obese (body mass index [BMI], 29 to 41 kg/m2) premenopausal women before and after a weight loss of 13.0 +/- 3.4 kg (mean +/- SD). A four-component (4C) model was used as the criterion. The other methods were as follows: three-component models (body density with total body water [3W] or bone minerals [3M]), underwater weighing, dual-energy x-ray absorptiometry ([DXA] XR-26, software 2.5.2; Norland, Ft Atkinson, WI), bioelectric impedance analysis (BIA) with an obese-specific equation [Segal et al), skinfolds (Durnin and Womersley), and an equation with BMI (Deurenberg et al). The 3W model (bias +/- SD, 0.5 +/- 0.4 kg), XR-26 (0.6 +/- 2.1 kg), and BMI equation (-0.3 +/- 2.1 kg) gave practically unbiased mean estimations of fat loss. All other methods underestimated fat loss by at least 1.6 kg (range of bias, -2.7 to -1.6 kg). The small bias (0.7 +/- 1.0 kg) between underwater weighing and model 4C before weight reduction indicates that the two-component assumptions were valid in premenopausal, weight-stable obese women. However, particularly the water fraction of the fat-free body component (4C model) was increased after weight reduction (before, 72.9% +/- 1.4%; after, 75.7% +/- 2.2%), making both underwater weighing and the 3M model uncertain for assessment of body composition changes. A general tendency for overestimating FM was seen before and more clearly after weight reduction. However, most methods underestimated fat loss, apparently because of unexpected changes in hydration of the fat-free body component.

Absorptiometry, Photon↗

PubMed1997

Total energy expenditure in human immunodeficiency virus-infected men and healthy controls.

Total daily energy expenditure (TEE) has been reported to be slightly decreased in weight-stable acquired immune deficiency syndrome (AIDS) patients. This conclusion is based on a comparison of TEE measurements to the data reported by others. We measured TEE in nine weight-stable human immunodeficiency virus (HIV)-infected homosexual men (Centers for Disease Control [CDC]-II to -IV) without active opportunistic disease and nine age-, sex-, and height-matched healthy controls using the doubly labeled water technique for 2 weeks, and resting energy expenditure (REE) using the ventilated-hood technique. TEE in HIV-Infected patients was not significantly different from that in healthy controls (221 +/- 12.5 and 210 +/- 9 kJ.kg lean body mass [LBM]-1.d-1, respectively, NS). REE was approximately 10% higher in HIV patients than in healthy controls (134 +/- 4 and 125 +/- 4 kJ.kg LBM-1.d-1, respectively, P = .02). The energy spent in relation to physical activity was not different between HIV-Infected patients and the controls (66 +/- 10 and 64 +/- 5 kJ.kg LBM-1.d-1, respectively, NS). In conclusion, REE is increased by about 10% in weight-stable HIV-infected men without active opportunistic disease. TEE and the energy spent during physical activity are not different in this group of patients versus healthy controls. This is in contrast to the previously reported decrease of TEE in weight-losing AIDS patients. Therefore, the energy requirements of stable HIV-infected patients are not decreased compared with those of healthy subjects.

Adult↗

PubMed1997

Validity of the Physical Activity Scale for the Elderly (PASE): according to energy expenditure assessed by the doubly labeled water method.

The study investigates the validity of the Physical Activity Scale for the Elderly (PASE) in 21 Dutch elderly men and women. The PASE is an easily scored, brief questionnaire for elderly, suitable for large epidemiologic studies. The PASE score was compared with physical activity measured with the doubly labeled water method. The correlation coefficient of the PASE score with the residuals from the regression analysis using total energy expenditure as dependent and resting metabolic rate as independent variate was 0.58 (95% CI = 0.50-0.81). Women had greater engagement in extremely high scoring activities as housework and taking care of others, resulting in higher PASE scores than men (97.9 and 71.9). The higher scores in women were not linked to higher activity levels, which suggests that the mentioned activities may be overvalued. Sex specific correlation coefficients were 0.79 (CI = 0.32-0.95) and 0.68 (CI = 0.15-0.90) for men and women, respectively. In conclusion, the PASE proved to be a reasonable valid method to classify healthy elderly men and women into categories of physical activity. Some possible refinements were suggested, which may improve the accuracy of the PASE questionnaire.

Activities of Daily Living↗

PubMed1997

Energy expenditure and physical activity in relation to bone mineral density in women with anorexia nervosa.

OBJECTIVES: To assess sleeping metabolic rate (SMR), average daily metabolic rate (ADMR), and total bone mineral density (TBMD) in women with anorexia nervosa, and to evaluate the effect of daily physical activity on TBMD. DESIGN: We compared women with anorexia nervosa and controls using measurements on body composition, and energy expenditure. Relations between these measurements were investigated. SETTING: Daily living environments in The Netherlands, and body composition and energy expenditure laboratory of the Department of Human Biology. SUBJECTS: Twelve adult, non-hospitalized women with anorexia nervosa, and sixteen adult normal weight women. INTERVENTIONS: Average daily metabolic rate was measured with the doubly labeled water method and sleeping metabolic rate in a respiration chamber. TBMD was measured by dual energy X-ray absorptiometry, and percentage body fat was calculated combining the results from underwater weighing and deuterium dilution. RESULTS: TBMD was significantly lower in anorexia than in controls (0.989 +/- 0.081 vs 1.144 +/- 0.054 g/cm2). Also ADMR and SMR were reduced in anorexia. The physical activity index (PAI = ADMR/SMR) was not significantly different from PAI in controls. In anorexia, TBMD was related to the PAI (R2 = 0.35, P < 0.05). Finally, stepwise multiple regression revealed that PAI together with the study groups as dummy variables could explain 69% of the variation in TBMD. CONCLUSION: These findings show that in anorexia TBMD is reduced, but that nonetheless physical activity has a significant positive effect on bone density.

Absorptiometry, Photon↗

PubMed1997

Relationship between physical activity related energy expenditure and body composition: a gender difference.

OBJECTIVE: The doubly labeled water method for the measurement of average daily metabolic rate (ADMR), combined with a measurement of basal metabolic rate (BMR), permits the calculation of energy expenditure for physical activity. Thus, the relation between physical activity and body composition (%body fat) can be determined. METHOD: We analyzed existing data sets with observations on ADMR, BMR, and %body fat including 290 healthy subjects, age 18-49 y, 146 females and 144 males, from 22 different studies. RESULTS: In a regression analysis, age explained 3-7% and 5-20% of the variation in %body fat in females and males, respectively. Adding physical activity to the model raised the explained variation in %body fat in males (partial r = -0.35, P < 0.01). A higher level of physical activity was related to a lower %body fat. In females, there was no relationship between physical activity and body composition (partial r = 0.00, n.s.). CONCLUSION: In males, there is a significant inverse cross-sectional relationship between activity energy expenditure and percent body fat, whereas no such relationship was apparent in females.

Adipose Tissue↗

PubMed1997

Energy balance in a respiration chamber: individual adjustment of energy intake to energy expenditure.

OBJECTIVES: In studies on substrate utilization, a state of energy balance is often required. Energy requirements are based on measured or calculated sleeping metabolic rate (SMR) or basal metabolic rate (BMR). A study was performed to compare this protocol with adjustment of energy intake (EI) to 24 h energy expenditure (24 h EE). DESIGN: In part one, eight subjects spent one night and the subsequent three days in a respiration chamber. On day 1 EI was set at 1.5*SMR. On day 2 and 3 EI was set at 24 h EE of day 1. In part two of the study, an activity protocol was provided while staying in the chamber. 12 subjects spent one night and the subsequent two days in the respiration chamber. On day 1 EI was set at 1.55*SMR and on day 2 EI was set at 24 h EE of day 1. MEASUREMENTS: Sleeping metabolic rate, diet induced thermogenesis, physical activity index and 24 h expenditure were measured using a respiration chamber. SUBJECTS: Eight healthy normal-weight females (age: 22 +/- 3, BMI: 20.9 +/- 1.8) in part one and twelve healthy normal-weight males and females (age: 26 +/- 2, BMI: 21.4 +/- 0.5) in part two of the study. RESULTS: Physical activity index (PAI = 24 h EE/SMR) on day 1 (part 1) was 1.55 +/- 0.04, close to the predicted value of 1.5, but between-subject variation was large (range: 1.39-1.68). Absolute deviation from energy balance reduced significantly from 1.35 +/- 0.30 MJ/d on day 1 to 0.51 +/- 0.21 and 0.31 +/- 0.10 MJ/d on day 2 and 3 respectively (P < 0.05). The latter can be considered as near to energy balance. With the activity protocol (part 2) absolute deviation from energy balance reduced significantly from 0.93 +/- 0.20 MJ/d on day 1 to 0.27 +/- 0.11 MJ/d on day 2 (P < 0.05). CONCLUSION: A three day stay in the chamber allows adjustment of energy intake to energy expenditure, in this way achieving a state close to energy balance. When prescribing an activity protocol the same results can be obtained within two days.

Adaptation, Physiological↗

PubMed1997

Calcium excretion, apparent calcium absorption and calcium balance in young and elderly subjects: influence of protein intake.

The present study was conducted to investigate the effect of dietary protein on urinary Ca excretion, apparent Ca absorption and Ca balance in young and elderly subjects. Young adults (n 29) and elderly persons (n 26) consumed diets containing 12% (diet A) and 21% (diet B) of total energy as protein for 3 weeks according to a randomized crossover design. Results showed no differences between the two age groups with respect to the interaction between protein intake and Ca excretion (both in urine and in faeces), apparent Ca absorption and Ca balance. Therefore analyses were done for both age groups separately and also for the whole group. In elderly persons and in the whole group the Ca excretion in faeces (as a percentage of Ca intake) was lower during the higher protein intake (elderly: diet A, 106 (SEM 7)%; diet B, 86 (SEM 7)%; P = 0.018; whole group: diet A, 99 (SEM 4)%; diet B, 84 (SEM 4)%; P = 0.003). In young adults faecal Ca excretion tended to be lower when they consumed diet B (diet A: 94 (SEM 5)%; diet B: 83 (SEM 6)%; P = 0.093). Relative urinary Ca excretion was greater during the higher protein intake in young adults and in the whole group while relative urinary Ca excretion was not different in the elderly (diet A: 15 (SEM 1)%, 14 (SEM 1)%, 15 (SEM 1)%; diet B: 16 (SEM 1)%, 16 (SEM 1)%, 17 (SEM 2)% for the whole group, the young and elderly subjects respectively, P = 0.019; P = 0.016; P = 0.243). The resulting Ca balance was not influenced by the amount of protein in the diet in young adults. Values for the elderly and for the whole group showed that the Ca balance during diet A was significantly more negative compared with Ca balance during diet B, despite the higher urinary Ca excretion during diet B. It can be concluded that increasing the protein intake from 12 to 21% of total energy intake had no negative effect on Ca balance.

Adult↗

PubMed1997

Changes in fat oxidation in response to a high-fat diet.

Intervention studies have shown that the adaptation of fat oxidation to fat intake, when the dietary fat content is changed, is not abrupt. This study was conducted to measure the time course of adaptation of oxidation rates to increases in the fat content of the diet while subjects were fed at energy balance. Twelve healthy, nonobese males and females [age: 26 +/- 2 y, body mass index (in kg/m2): 21.4 +/- 0.5; and habitual fat intake: 29 +/- 1% of energy] consumed a low-fat diet for 6 d (days 1-6) followed by a high-fat diet for 7 d (days 7-13). Days 5-9 and 13 were spent in a respiration chamber. After adjustment for energy intake to 24-h energy expenditure on day 5, subjects were in energy balance (range: -0.15 to 0.23 kJ/d) on days 6-9 and 13. Fat balance was zero on day 6 but became positive after subjects changed to the high-fat diet (1.06 +/- 0.15, 0.75 +/- 0.15, and 0.55 +/- 0.14 MJ/d for days 7, 8, and 9, respectively, P < 0.05), reaching a new balance on day 13, 7 d afterward. In conclusion, when in energy balance, lean subjects are capable of adjusting fat oxidation to fat intake within 7 d of when dietary fat content is increased.

Adaptation, Physiological↗

PubMed1997

The effect of an increase of protein intake on whole-body protein turnover in elderly women is tracer dependent.

To compare the response of whole-body protein turnover with variations in dietary protein level, whole-body protein turnover was measured by different stable isotope methods in six elderly women (69 +/- 5 y) consuming two levels of protein (10 and 20% of total energy, diets A and B, respectively). Protein turnover was measured during 12 h of overnight fasting with 15N-glycine with urea and ammonia as end products. During the last 4 h of the interval, protein turnover was also estimated by -[1-13C]-leucine infusion. Nitrogen balance [diet A, -0.040 +/- 0.015 g/(kg.d); diet B, 0.002 +/- 0.053 g/(kg.d); mean +/- ] did not differ significantly between the diet periods, although all subjects were in negative nitrogen balance at the end of diet A. Protein breakdown, as measured with 15N-glycine, did not differ from results obtained using -[1-13C]-leucine, whereas protein synthesis was found to be significantly lower using the former isotope. The 15N-glycine method indicated that protein turnover (both synthesis and breakdown) was higher in fasting elderly women when they consumed a 20% rather than a 10% protein diet, whereas the -[1-13C]-leucine method did not show significant differences between the diet periods in the last 4 h of the overnight fasting period. However, the relative increase in net protein breakdown when comparing diet B with diet A, was comparable for both tracers. These data indicate that care is needed with the choice of the tracer used in measuring the components of protein turnover in elderly women with the aim of understanding the physiological basis behind the adequacy of the level of protein intake.

Aged↗

PubMed1997

Total daily energy expenditure relative to resting energy expenditure in clinically stable patients with COPD.

BACKGROUND: An elevated resting energy expenditure (REE) commonly occurs in patients with chronic obstructive pulmonary (COPD). The purpose of this study was to investigate the effect of an increased REE on total daily energy expenditure (TDE) in 20 patients with COPD (19 men) with mean (SD) forced expiratory volume in one second of 37 (14)% predicted. METHODS: TDE was measured over a two week interval using doubly labelled water. Fat-free mass (FFM) was calculated from total body water assessed by deuterium dilution. REE was measured by indirect calorimetry using a ventilated hood system. RESULTS: The patients (10 men) with a significantly higher REE than those with a normal REE (median difference 205 kcal/ 24 h, p < 0.05) had a comparable TDE (hypermetabolic at rest: median 2593; range 2127-3083 kcal/24 h, normometabolic at rest: median 2629; range 2032-3179 kcal/ 24 h). There was no difference in mean daily heart rate (HR) between the groups (hypermetabolic at rest: median 92 (range 82-98), normometabolic at rest: median 98 (range 75-116) beats/min) or in the variation in the heart rate during the day. By means of multiple regression analysis it was shown that REE did not correlate significantly with TDE when FEM was taken into account. CONCLUSIONS: This study shows that there is no significant difference in free living TDE between clinically stable patients with COPD with a normal REE and those with an increased REE. The variation in TDE in patients with COPD appears to reflect differences in energy expenditure for activities, but not differences in REE.

Aged↗

PubMed1997

Role of glycogen-lowering exercise in the change of fat oxidation in response to a high-fat diet.

One of the candidate factors for determining the increase of fat oxidation after a switch from a reduced-fat diet to a high-fat diet is the size of the glycogen storage. Therefore, we studied the effect of low glycogen stores on fat oxidation after a switch from a reduced-fat diet to a high-fat diet. Twelve healthy, nonobese males and females (age: 22 +/- 1 yr, body mass index: 21.0 +/- 0.7, maximal power output: 254 +/- 11 W) consumed a reduced-fat (RF) diet (30, 55, and 15% of energy from fat, carbohydrate, and protein, respectively) three times a day at home for 3 days (days 1-3). On two occasions subjects came to the laboratory on day 3 at 1500 to perform an exhaustive glycogen-lowering exercise (EX), after which they went into the respiration chamber for a 36-h stay. On one occasion, subjects directly entered the respiration chamber at 1800 for a 36-h stay. In the respiration chamber they were given either a high-fat (HF) diet (60, 25, and 15% of energy from fat, carbohydrate, and protein, respectively) or a RF diet. In both cases they were fed at energy balance. All diets were consumed as breakfast, lunch, dinner, and two or more snacks per day. On the HF treatment, fat oxidation was below fat intake, indicating the slow change of oxidation to intake on a HF diet. After the HF+EX treatment, however, fat oxidation matched fat intake. In conclusion, lean subjects are capable of rapidly adjusting fat oxidation to fat intake when glycogen stores are lowered by exhaustive exercise.

Acclimatization↗

PubMed1997

Effect of an 18-wk weight-training program on energy expenditure and physical activity.

The purpose of this study was to examine the effect of an 18-wk weight-training program on average daily metabolic rate (ADMR). Before the intervention and in weeks 8 and 18 (T0, T8, and T18, respectively) data on body composition, sleeping metabolic rate (SMR), food intake, energy cost of the weight-training program (EEex), and nontraining physical activity (accelerometer) were collected in the exercise group (EXER, n = 18 males). ADMR was determined in a subgroup (EX12, n = 12) by using doubly labeled water. At T0 and T18, data (except ADMR) were also collected in a control group (Con, n = 8). Body mass did not change in EXER or Con. Fat-free mass increased only in EXER with 2.1 +/- 1.2 kg, whereas fat mass decreased in EXER as well as Con (2.0 +/- 1.8 and 1.4 +/- 1.0 kg, respectively). Initial ADMR (12.4 +/- 1.2 MJ/day) increased at T8 (13.5 +/- 1.3 MJ/day, P < 0.001) with no further increase at T18 (13.5 +/- 1.9 MJ/day). SMR did not change in EXER (4.8 +/- 0.5, 4.9 +/- 0.5, 4.8 +/- 0.5 kJ/min) or Con (4.7 +/- 0.4, 4.8 +/- 0.4 kJ/min). Energy intake did not change in EXER (10.1 +/- 1.8, 9.7 +/- 1.8, 9.2 +/- 1.9 MJ/day) or Con (10.2 +/- 2.6, 9.4 +/- 1.8, 10.1 +/- 1.5 MJ/day) and was systematically underreported in EX12 (-21 +/- 14, -28 +/- 18, -34 +/- 14%, P < 0.001). EEex (0.47 +/- 0.20, 0.50 +/- 0.18 MJ/day) could only explain 40% of the increase in ADMR. Nontraining physical activity did not change in both groups. In conclusion, although of modest energy cost, weight-training induces a significant increase in ADMR.

Adult↗

PubMed1997

A dual-respiration chamber system with automated calibration.

This study characterizes respiration chambers with fully automated calibration. The system consists of two 14-m3 pull-type chambers. Care was taken to provide a friendly environment for the subjects, with the possibility of social contact during the experiment. Gas analysis was automated to correct for analyzer drift and barometric pressure variations and to provide ease of use. Methods used for checking the system's performance are described. The gas-analysis repeatability was within 0.002%. Results of alcohol combustion (50-350 ml/min CO2) show an accuracy of 0.5 +/- 2.0 (SD) % for O2 consumption and -0.3 +/- 1.6% for CO2 production for 2- to 24-h experiments. It is concluded that response time is not the main factor with respect to the smallest practical measurement interval (duration); volume, mixing, gas-analysis accuracy, and levels of O2 consumption and CO2 production are at least equally important. The smallest practical interval was 15-25 min, as also found with most chamber systems described in the literature. We chose to standardize 0.5 h as the minimum measurement interval.

Atmosphere Exposure Chambers↗

PubMed1997

Total free living energy expenditure in patients with severe chronic obstructive pulmonary disease.

Resting energy expenditure (REE) is often elevated in patients with chronic obstructive pulmonary disease (COPD), but no data are available regarding total energy expenditure in free living conditions. We compared total daily energy expenditure (TDE) in eight COPD patients (FEV1 36 +/- 13%) admitted to a pulmonary rehabilitation center and eight independently living healthy subjects, matched for sex, age, and body mass index (BMI). TDE was measured over a 2-wk interval using doubly labeled water in combination with measurement of REE and body composition. The COPD patients had a significantly higher TDE than the healthy subjects (2,499 +/- 320 kcal/d and 2,107 +/- 88 kcal/d, respectively, p < 0.01). The nonresting component of TDE (TDE-REE: physical activity and diet-induced thermogenesis [DIT]) was significantly higher in the COPD patients than in the healthy subjects, resulting in a ratio between TDE and REE of 1.7 +/- 0.2 and 1.4 +/- 0.1, respectively (p < 0.01). The results indicate that COPD patients exhibit an increased TDE in comparison with healthy subjects. The difference could by attributed to an increase in the nonresting component of TDE, since REE was comparable between the groups.

Activities of Daily Living↗