Resting VO2, maximal VO2 and metabolic equivalents in free-living healthy elderly women.

BACKGROUND & AIMS: Maximal VO2 (VO2max) and metabolic equivalents (METs) decline with aging due to body composition and cardiovascular modifications. However, a detailed evaluation of these variables for this population has not been done. The aim of this study was to evaluate VO2max and METs in healthy elderly women, and to establish whether the calculated resting VO2 (3.5 ml/min/kg) underestimates the true METs. METHODS: 81 females over 65 years old attending a twice-weekly mild fitness program were studied. Body composition was measured by DEXA. VO2max and resting VO2 (VO(2rest-meas)) were measured by indirect calorimetry. METs were measured (METs-meas) using the VO2max/VO(2rest-meas) ratio, and calculated (METs-cal) from the ratio between measured VO2max and calculated resting VO2 (3.5 ml/min/kg of body weight). RESULTS: The VO(2rest-meas) and VO2max measured by indirect calorimetry were 2.9+/-0.4 ml/min/kg and 17.5+/-2.8 ml/min/kg, respectively. The METs-meas were higher than the METs-cal (6.1+/-1.2 vs 5.0+/-0.8; p<0.001). The 25th-75th percentile range of measured METs was 5.2-6.8. CONCLUSIONS: Our study confirmed that, in elderly women, METs values ranging between 5 and 7 are compatible with an acceptable physical activity. The estimated resting VO2 (3.5 ml/min/kg) does not appear to be applicable to elderly women, because it underestimates the real METs in this population.

Resting energy expenditure and body composition in bedridden institutionalized elderly women with advanced-stage pressure sores.

BACKGROUND: Our study investigated nutritional status, body composition, and resting energy expenditure (REE) in elderly patients with advanced-stage pressure sores (PS), in addition to researching any hypermetabolic condition and its relationship with PS size. METHODS: The study involved 52 institutionalized bedridden elderly women (aged 83.7 +/- 6.3 years), divided into two groups: 23 with advanced-stage (stage 3 and 4) PS and 29 without PS. Albumin, prealbumin, and retinol-binding protein were measured in all patients, and fat-free mass (FFM) and fat mass (FM) were obtained by dual-energy x-ray absorptiometry (DEXA). REE was measured by indirect calorimetry and predicted with the Harris-Benedict formula. PS area and volume were also measured. RESULTS: The elderly women with and without PS were comparable in age, FFM, and FM. Mean albumin, prealbumin, and retinol-binding protein values were lower in cases with PS. Unadjusted mean REE was significantly higher in patients with PS (1212.3 +/- 236.7 vs 1085.5 +/- 161.3 kcal/d; p <.05), even after adjusting for FFM or expressed per kilogram of body weight (25.8 +/- 6.7 vs 21.1 +/- 4.0 kcal/d/kg; p <.01). Hypermetabolism, i.e., a measured REE > 110% of the predicted REE, was seen in 74% of patients with PS and 38% of controls. The difference between measured and predicted REE (DeltaREE) correlated with PS volume (r = 0.58; p <.01), but not with area. CONCLUSION: Advanced-stage PS in elderly women are associated with a hypermetabolic state that is influenced by the volume of the PS.

Body composition and resting energy expenditure in elderly male patients with chronic obstructive pulmonary disease.

STUDY OBJECTIVE: Our study investigates nutritional status, resting energy expenditure (REE) and physical performance in elderly patients with stable COPD to identify any early conditions of hypermetabolism, malnutrition and sarcopenia. METHODS: Eighty-six males (40 stable COPD and 46 healthy subjects) over 65 years old were studied. All subjects underwent spirometry, blood gas analysis and a 6-min walking test (6MWT). Fat-free mass (FFM) and appendicular skeletal muscle mass (ASMM) were measured by dual energy X-ray absorptiometry (DEXA). REE was measured by indirect calorimetry. RESULTS: COPD patients had a lower FFM both expressed in kilograms and after correction for height squared. The prevalence of sarcopenia was higher for COPD subjects (38% vs 31%). REE, both in absolute values and adjusted for FFM was significantly higher in COPD patients. Hypermetabolism was found in 60% of COPD cases and 13.7% (P<0.01) of healthy subjects. No relationship was found in COPD patients between the measured/predicted REE ratio (REE(m)/REE(p)) and FEV1. In the hypermetabolic COPD subgroup, the REE(m)/REE(p) ratio correlated with 6MWT. CONCLUSIONS: Elderly patients with stable COPD develop an increased REE. This hypermetabolism seems to be independent of the severity of the pulmonary obstruction and to influence the patient's physical performance.