Influence of fat-free mass and functional status on resting energy expenditure in underweight elders

Association of Reduced Free T3 to Free T4 Ratio with Lower Serum Creatinine in Japanese Hemodialysis Patients

PURPOSE

Low T3 syndrome is defined by a fall in free triiodothyronine (FT3) in spite of normal serum thyroid-stimulating hormone (TSH) and often normal free thyroxin (FT4). A low FT3/FT4 ratio, a relevant marker for low T3 syndrome, is known as a risk of mortality in hemodialysis (HD) patients, as well as low muscle mass in the general population. Because of the local activation of T4 to FT3 in muscle tissue, we examined the association of FT3/FT4 ratio with serum creatinine, a marker of muscle mass and strength in HD patients to investigate the significance of muscle tissue in the development of low T3 syndrome in HD patients.

METHODS

This was a cross-sectional study derived from our prospective cohort study, named DREAM, of Japanese HD patients. After the exclusion of patients with treated and untreated thyroid dysfunction, 332 patients were analyzed in the study.

RESULTS

The serum FT4 and TSH of HD patients (n = 332) were 0.9 ± 0.1 ng/dL. and 2.0 ± 0.9 μIU/mL, which were within the respective normal range, while serum FT3 was 2.2 ± 0.3 pg/mL. As many as 101 out of 332 (30.4%) HD patients exhibited a serum FT3 less than the normal lower limit of 2.2 pg/mL. The serum FT3/FT4 ratio correlated significantly positively with serum creatinine, and inversely with serum log CRP and total cholesterol, while it exhibited a tendency towards positive correlation with serum albumin. Multiple regression analysis, which included serum creatinine, albumin, and log CRP, simultaneously, in addition to sex, age, diabetic kidney disease or not, log HD duration, body mass index, systolic blood pressure, and Kt/V, as independent variables, revealed an independent and significant positive association of serum creatinine, but not serum albumin or CRP, with the serum FT3/FT4 ratio.

CONCLUSIONS

The present study demonstrated an independent and positive correlation of serum creatinine with the serum FT3/FT4 ratio in HD patients. The lack of association of the serum FT3/FT4 ratio with serum albumin and CRP suggested the presence of a creatinine-specific mechanism to associate with serum FT3/FT4 ratio. Because of the local activation of T4 to T3 at muscle tissue, a lower muscle mass may be causatively associated with low T3 syndrome.

Implications of evaluating leg muscle mass and fat mass separately for quadriceps strength in knee osteoarthritis: the SPSS-OK study

OBJECTIVE

To examine the influence of obesity on quadriceps strength by separately analyzing body mass index (BMI) as fat mass and leg muscle mass in patients with knee osteoarthritis (KOA).

METHODS

The Screening for People Suffering Sarcopenia in Orthopedic cohort of Kobe (SPSS-OK) study was a single-center cross-sectional study that recruited 906 patients with KOA. Fat mass and leg muscle mass were measured by bio-impedance. Isometric knee extension torque (Nm) was measured as quadriceps strength. A series of general linear models were fitted to estimate the continuous associations of BMI and fat mass with quadriceps strength, with adjustment of confounders. In the fitted models, both BMI and fat mass were treated as restricted cubic spline functions.

RESULTS

A continuous, non-linear relationship between BMI and quadriceps strength was found (P = 0.008 for non-linearity). In patients with a BMI of 16-25 kg/m², increasing quadriceps strength was observed. However, in patients with a BMI of 25-40 kg/m², quadriceps strength seemed similar. Additionally, an inverted U-shaped relationship between fat mass and quadriceps strength was demonstrated (P = 0.04 for non-linearity). In those with a fat mass of 10-20 kg, increasing quadriceps strength was seen. However, in patients with a fat mass of 20-30 kg, quadriceps strength showed a decreasing trend. Independent of fat mass, leg muscle mass was linearly associated with greater quadriceps strength.

CONCLUSION

Our study suggests that there are independent associations between the leg muscle mass, fat mass, and quadriceps strength. It is difficult to easily predict quadriceps strength using only BMI.

KEY POINTS

• An increase in body mass index (BMI) up to 25 kg/m²was associated with increasing quadriceps strength. • Quadriceps strength remained almost unchanged among patients with a BMI of > 25 kg/m². • The association between fat mass and quadriceps strength had an inverted U-shaped relationship, suggesting the importance of the separate assessment of fat mass and muscle mass in patients with knee osteoarthritis, especially those who are overweight or obese.

Energy Expenditure in Older People Hospitalized for an Acute Episode

Weight loss and worsening of nutritional state is a frequent downfall of acute hospitalization in older people. It is usually accepted that acute inflammation is responsible for hypercatabolism. However, several studies suggest, on the contrary, a reduction in resting energy expenditure (REE). This study aimed to obtain a reliable measure of REE and total energy expenditure (TEE) in older patients hospitalized for an acute episode in order to better assess patients' energy requirements and help understand the mechanisms of weight loss in this situation. Nineteen hospitalized older patients (mean age 83 years) with C-reactive protein (CRP) level >20mg/L were recruited. REE and TEE were measured using gold standard methods of indirect calorimetry and doubly labeled water (DLW), respectively. REE was then compared to data from a previous study on aged volunteers from nursing homes who were free of an acute stressor event. Energy requirements measured by DLW were confirmed at 1.3 × REE. Energy intake covered the needs but did not prevent weight loss in these patients. TEE was not increased in hospitalized patients and was not influenced by inflammation, while the relationship between REE and inflammation was uncertain. Our results suggest that lean mass remains the major determinant of REE in hospitalized older people and that weight loss may not be explained solely by a state of hypercatabolism.

The relationships between sarcopenic skeletal muscle loss during ageing and macronutrient metabolism, obesity and onset of diabetes

Skeletal muscle is integral to the metabolism and utilisation of macronutrients; however, substantial muscle loss and morphological changes occur with ageing. These are associated with loss of muscle function and accelerate rapidly from the age of 60 years, leading to the conditions of sarcopenia and frailty. As the relationship between muscle ageing and macronutrient metabolism and utilisation has seen limited research to date, this review focuses on the interactions between skeletal muscle changes during ageing, metabolism and utilisation of fat, carbohydrates and overall energy expenditure.Skeletal muscle contributes less to resting energy expenditure during ageing, potentially contributing to onset of obesity from middle age. Age-related changes to skeletal muscle lead to glucose dysregulation, with consequent reduction in glycaemic control, increased insulin resistance and ultimately onset of type-2 diabetes. Recent studies indicate that high total fat and SFA intake are detrimental to skeletal muscle, while higher intakes of PUFA are protective. Age-associated changes in skeletal muscle may also reduce total fatty acid utilisation.In conclusion, further research is needed to understand the relationships between macronutrient metabolism and utilisation and age-related changes to skeletal muscle. No dietary recommendations exist specifically for skeletal muscle health during ageing, but we advise individuals to follow healthy eating guidelines, by consuming sufficient protein, fruit and vegetables, and limited SFA and to maintain physically active lifestyles. Clinicians responsible for managing type-2 diabetes need to be aware of growing evidence relating age-related skeletal muscle changes to diabetes onset and progression.

Energy expenditure in women and men with COPD

BACKGROUND

Many patients with chronic obstructive pulmonary disease (COPD) lose weight. Successful nutritional intervention is vital, thus assessment of energy requirement is required. The aim of this study was to present an improved possibility to assess energy requirement in patients with COPD.

METHODS

Pub Med search was conducted for all the studies reporting total energy expenditure (TEE) measured by doubly labeled water (DLW) method in patients with COPD. Four studies were identified, whereof three were conducted in Sweden. The present analysis is based on these three studies of which the data was acquired.

RESULTS

There was a large variation in resting metabolic rate (RMR) and TEE. Body mass index decreased significantly with increase in disease severity (p < .001), and correlated significantly to forced expiratory volume in 1 s (FEV₁) % predicted (r = .627, p < .001). FEV₁% predicted had a significant correlation with RMR/kg body weight (BW)/day (r = -.503, p = .001), RMR/kg fat-free mass (FFM)/day (r = .338, p = .031), and TEE/kg FFM/day (r = .671, p < .001). Compared to men, women had a lower RMR and TEE/kg BW/day (p < .001 respectively p = .002), and higher RMR and TEE/kg FFM/day (p = .080 respectively p = .005). The correlates of: RMR/kg BW were gender and FEV1% predicted; of TEE/kg BW the correlates were age and gender, and of TEE/kg FFM the correlates were age and FEV1% predicted.

CONCLUSION

In this study, we have presented a possibility to assess energy requirement per kg BW/day and per kg FFM/day in patients with COPD in clinical settings. However, gender, age, and disease severity must be considered.

Gender-Specific Associations in Age-Related Changes in Resting Energy Expenditure (REE) and MRI Measured Body Composition in Healthy Caucasians

BACKGROUND

The effect of gender as well as gender-specific changes of fat free mass (FFM) and its metabolic active components (muscle mass and organ masses [OMs]) and fat mass (FM) on age-related changes in resting energy expenditure (REE) are not well defined. We hypothesized that there are gender differences in (1) the age-specific onset of changes in detailed body composition (2); the onset of changes in body composition-REE associations with age.

METHODS

Using a cross-sectional magnetic resonance imaging database of 448 Caucasian participants (females and males) with comprehensive data on skeletal muscle (SM) mass, adipose tissue (AT), OMs, and REE.

RESULTS

We observed gender-specific differences in the onset of age-related changes in metabolic active components and REE. Declines in body composition and REE started earlier in females than in males for SM (29.4 vs 39.6 years), AT (38.2 vs 49.9 years), OM (34.7 vs 45.7 years), and REE (31.9 vs 36.8 years). The age-related decrease of AT was significantly higher in females than in males (-5.69kg/decade vs -0.59kg/decade). In females adjusted REEmFFM&FM (resting energy expenditure measured adjusted for FFM and FM) and REEmSM/OM/AT (resting energy expenditure measured adjusted for skeletal muscle and organ mass and adipose tissue) decreased by -145 kJ/d/decade and -604.8 kJ/d/ decade after the age of 35.2 respectively 34.3 years. SM was main determinant of REEm in females (R (2) = .67) and males (R (2) = .66) with remaining variance mainly explained by kidney mass (R (2) = .07) in females and liver mass (R (2) = .09) in males.

CONCLUSION

We concluded that gender affects the age-related changes in body composition as well as changes in body composition-REE relationship. This trial was registered at linicaltrials.gov as NCT01737034.

The Association between Parameters of Malnutrition and Diagnostic Measures of Sarcopenia in Geriatric Outpatients

Objectives

Diagnostic criteria for sarcopenia include measures of muscle mass, muscle strength and physical performance. Consensus on the definition of sarcopenia has not been reached yet. To improve insight into the most clinically valid definition of sarcopenia, this study aimed to compare the association between parameters of malnutrition, as a risk factor in sarcopenia, and diagnostic measures of sarcopenia in geriatric outpatients.

Material and Methods

This study is based on data from a cross-sectional study conducted in a geriatric outpatient clinic including 185 geriatric outpatients (mean age 82 years). Parameters of malnutrition included risk of malnutrition (assessed by the Short Nutritional Assessment Questionnaire), loss of appetite, unintentional weight loss and underweight (body mass index <22 kg/m²). Diagnostic measures of sarcopenia included relative muscle mass (lean mass and appendicular lean mass [ALM] as percentages), absolute muscle mass (total lean mass and ALM/height²), handgrip strength and walking speed. All diagnostic measures of sarcopenia were standardized. Associations between parameters of malnutrition (independent variables) and diagnostic measures of sarcopenia (dependent variables) were analysed using multivariate linear regression models adjusted for age, body mass, fat mass and height in separate models.

Results

None of the parameters of malnutrition was consistently associated with diagnostic measures of sarcopenia. The strongest associations were found for both relative and absolute muscle mass; less stronger associations were found for muscle strength and physical performance. Underweight (p = <0.001) and unintentional weight loss (p = 0.031) were most strongly associated with higher lean mass percentage after adjusting for age. Loss of appetite (p = 0.003) and underweight (p = 0.021) were most strongly associated with lower total lean mass after adjusting for age and fat mass.

Conclusion

Parameters of malnutrition relate differently to diagnostic measures of sarcopenia in geriatric outpatients. The association between parameters of malnutrition and diagnostic measures of sarcopenia was strongest for both relative and absolute muscle mass, while less strong associations were found with muscle strength and physical performance.

Dietary intake and physical performance in healthy elderly women: a 3-year follow-up

BACKGROUND

Aging is generally accompanied by changes in body composition, muscle mass and strength, leading to a decline in motor and functional performance. Physical activity and eating habits could be involved in modulating this paraphysiological deterioration. Aim of our study was to investigate changes in body composition, diet and physical performance in healthy, elderly females over a 3-year follow-up.

METHODS

92 healthy elderly females (70.9±4.0 years) attending a twice-weekly mild fitness program were eligible for the study. They were assessed at baseline and again after 3 years in terms of clinical history, diet, body composition by DEXA, resting energy expenditure, handgrip strength, knee extensor isometric/isotonic strength, and functional performance measured using the Short Physical Performance Battery (SPPB).

RESULTS

After 3 years, women had a significant decline in muscle strength (∆ isotonic: -1.4±4.3 kg, ∆ isokinetic: -2.0±6.3 kg, ∆ handgrip: -3.2±5.0 kg; p<0.001) and physical performance (∆ walking time: 0.71±0.9 s, ∆ walking speed: -0.25±0.35 m/s; p<0.001), while their weight and body composition parameters did not change, except for a small decrease in appendicular skeletal muscle mass (-0.4±1.4 kg). There was a significant drop in calorie (∆:-345.7±533.1 kcal/d; p<0.001) and protein intake (∆:-0.14±0.23 g/d; p<0.001), while resting energy expenditure remained stable. ∆ calorie intake correlated with the variation in 4-meter walking time (r: 0.34; p<0.01).

CONCLUSIONS

With advancing age, physical performance declines even in healthy, fit females despite a spare of weight and body composition. This decline in physical activity could lead to a lower calorie intake, which would explain why there is no variation in body weight.

Body circumferences are predictors of weight adjusted resting energy expenditure in older people

OBJECTIVE

To evaluate predictors of resting energy expenditure (REE) in older people which are more comfortable for them than indirect calorimetry and which are suitable for field studies.

DESIGN

Cross-sectional study.

SETTING

Department of Human Biology, Kiel University.

PARTICIPANTS

100 (51 males, 49 females) healthy independently-living normal-weight (BMI, males 26.0±2.67 kg/m², females 25.0±3.29 kg/m²) Germans, aged 60-83 years.

MEASUREMENTS

REE, body composition, anthropometry, peak expiratory flow rate (PEF), and physical activity level were determined using indirect calorimetry, bioimpedance analysis, anthropometrics, peak-flow-meter, and standardized questionnaire, respectively. Stepwise linear multiple regression analysis was performed with REE or weight adjusted REE as dependent variables. Independent variables were body height, weight, body mass index (BMI), waist circumference, abdomen circumference, hip circumference, waist-to-hip ratio (WHR), lean body mass (LBM), PEF, and physical activity level.

RESULTS

The only significant predictor of REE was LBM in males and BMI in females. Trunk circumferences emerged as strong predictors of weight adjusted REE. Abdomen circumference and hip circumference explained in males and females 69% and 70% of variation in adjusted REE, respectively. Weaker predictors were LBM in males (R² increased from 0.69 to 0.80) as well as body height and BMI in females (R² increased from 0.70 to 0.91). Waist circumference, WHR, physical activity level, and PEF were no significant determinants of adjusted REE.

CONCLUSION

These findings demonstrate that trunk circumferences, but not WHR, are very strong predictors of weight adjusted REE in non-geriatric older people. This implies that the sex-specific use of abdomen or hip circumference in combination with LBM or body height and BMI seems to be well sufficient to predict weight adjusted REE in the aged. These measures might also be of clinical relevance, because they are more comfortable for older sick people than indirect calorimetry. Further studies are needed to test the applicability of the prediction equations to frail older populations.

Fat-free mass and fat mass reference values by dual-energy X-ray absorptiometry (DEXA) in a 20-80 year-old Italian population

BACKGROUND & AIMS

To establish reference values for fat-free mass (FFM), the FFM index (FFMI), fat mass (FM) and the FM index (FMI) in an Italian adult population, developing percentile distribution curves for age brackets between 20 and 80 years.

METHODS

A multicenter, retrospective study was conducted on a sample of 1866 healthy Italian adults, 1435 females and 431 males. FFM and FM were measured by dual-energy X-ray absorptiometry. FFMI and FMI were calculated as the ratio of FFM and FM to height squared.

RESULTS

The reference range for the FFMI (25-75th percentile) was similar in all age groups, i.e. 18.7-21 kg/m(2) in men and 14.9-17.2 kg/m(2) in women. In both genders, FM, the FMI and FM as a percentage of body weight (FM%) increased with age. The reference values for FM% in the two age brackets 20-29 and 60-69 were, respectively, 13-20% and 22.5-29.3% for men and 26.1-34.9%, 32.5-39.6% for women.

CONCLUSIONS

These body composition ranges can be used by clinicians and nutritionists as reference values for a Caucasian population in the Mediterranean area when evaluating body composition variations occurring in aging, malnutrition and chronic diseases.

Energy requirements in frail elderly people: A review of the literature

This review collates studies of healthy, sick, underweight (BMI < or = 21 kg/m2) and very elderly people (> or = 90 yr), in whom resting energy expenditure (REE) was measured using indirect calorimetry. We have observed the following: (1) REE, when adjusted for differences in both body weight and fat-free mass (FFM), is similar in healthy and in sick elderly people being 20 and 28 kcal/kg of FFM per day, respectively, (2) their nutritional status influences their energy requirements given that weight-adjusted REE increases in line with a decrease in BMI, (3) total energy expenditure is lower in sick elderly people given that their physical activity level, i.e. the ratio of total energy expenditure to REE, is reduced during disease averaging at 1.36, (4) energy intake (EI) being only 1.23 x REE is insufficient to cover energy requirements in sick elderly patients, whereas the EI of healthy elderly people appears sufficient to cover requirements, and finally, (5) gender ceases to be a determinant of REE in people aged 60 yr or over, with the Harris & Benedict equation capable of accurately predicting mean REE in this population, whether healthy or sick.

Role of visceral proteins in detecting malnutrition in the elderly

OBJECTIVE

In the clinical practice, visceral proteins are used as indirect markers of protein energy malnutrition (PEM), but their reliability could be reduced with advancing age. The aim of this work is to investigate the reliability of albumin, prealbumin, retinol-binding protein (RBP) and transferrin in evaluating nutritional status in old patients and their relationship with fat-free mass (FFM).

DESIGN

Cross-sectional study.

SETTING

Padua, Italy.

SUBJECTS

In 44 underweight (body mass index < 20 kg/m(2)) (66-97 years) and 69 normal weight or overweight elderly subjects (62-98 years), albumin, prealbumin, transferrin and RBP were determined in the plasma. Body composition and particularly FFM was obtained by dual X-ray absorptiometry. FFM was also expressed as FFM index (FFMI) calculated as FFM divided by height squared. Subjects affected by acute illnesses and inflammatory states were excluded.

RESULTS

Albumin, prealbumin and RBP mean values were significantly lower in underweight subjects. No differences between two groups were found for transferrin. Albumin prealbumin and RBP resulted under the normal range in 55, 25 and 54% of underweight subjects, respectively. Transferrin's values were low in about 40% of underweight and normal weight subjects, respectively. In all subjects, FFMI shows a significant correlation with albumin (r: 0.52), prealbumin (r: 0.64) and RBP (r: 0.57). No correlation between FFMI and transferrin was found.

CONCLUSIONS

Visceral proteins, except for transferrin, seem to be useful indexes in detecting malnutrition in the elderly; low values still in the normal range should also be carefully evaluated because they could suggest a poor nutritional status.

Body composition in underweight elderly subjects: reliability of bioelectrical impedance analysis

BACKGROUND AND AIMS

In underweight elderly subjects it is important to estimate body composition and particularly fat-free mass (FFM). Bioelectrical impedance analysis (BIA) is a non-invasive method in determining FFM, but its usefulness in these frail subjects should be verified. The aim of this study is to verify in underweight elderly people the reliability of previously published BIA formulas in detecting FFM.

METHODS

Fifty-seven hospitalized elderly subjects (27 males and 30 females) with body mass index <20 kg/m(2) were selected. In all subjects, FFM was detected by dual energy X-ray absorptiometry. Moreover, BIA measurements were performed at standard frequency (50 kHz and 800 microA) and FFM was derived using the main previous published BIA equations.

RESULTS

In men, Kyle and Rising equations gave acceptable estimates of FFM with a mean error, respectively, of 1+/-1.9 and 1.4+/-1.7 kg. Also RJL formula could be used after adjusting for a correction factor. In women, no equation seemed sufficiently reliable to estimate FFM.

CONCLUSIONS

BIA method seems useful to evaluate body composition in underweight elderly men but it seems to have intrinsic limits in women. Nevertheless, the variability in behavior of the different equations suggests to be careful in adopting BIA equations.

Nutritional risk and body composition in free-living elderly participating in congregate meal-site programs

Early detection of nutritional risk in free-living elderly is critical in healthcare, yet comprehensive measurements are time consuming and can be frustrating to both health professionals and elderly. In addition, body composition measurements provide information regarding fat and fat-free mass that have been linked to morbidity and mortality in elderly. In this study, nutritional risk was assessed in 69 elderly, aged 50-90 years, attending congregate meal-site programs, using Mini Nutritional Assessment, and body composition was assessed by bioelectric impedance. Analysis revealed that 31.9% of the elderly were at risk for malnutrition and 2.9% were malnourished. Males had significantly greater body weight, height and fat-free mass, and females had significantly greater body fat as percentage of body weight, but there was no gender difference in nutritional risk. Of elderly, 36.2% had body mass index > 85th percentile and 8.7% < 15th percentile using national population reference standards. Age-related decline in fat-free mass was an early indicator of changes in body composition.

Energetic cost of breathing, body composition, and pulmonary function in horses with recurrent airway obstruction

This study was conducted to determine whether horses with naturally occurring, severe chronic recurrent airway obstruction (RAO) 1) have a greater resting energy expenditure (REE) than control horses, 2) suffer body mass depletion, and 3) have significantly decreased REE after bronchodilation and, therefore, also 4) whether increased work of breathing contributes to the cachexia seen in some horses with RAO. Six RAO horses and six control horses underwent indirect calorimetric measures of REE and pulmonary function testing using the esophageal balloon-pneumotachograph method before and after treatment with ipratropium bromide, a parasympatholytic bronchodilator agent, at 4-h intervals for a 24-h period. Body condition scoring was performed, and an estimate of fat mass was determined via B-mode ultrasonography. O2 and CO2 fractions, respiratory airflow, respiratory rate, and pleural pressure changes were recorded, and O2 consumption, CO2 production, REE, pulmonary resistance, dynamic elastance, and tidal volume were calculated. In addition, we performed lung function testing and calorimetry both before and after sedation in two control horses. RAO horses had significantly lower body condition scores (2.8 ± 1.0 vs. 6.4 ± 1.2) and significantly greater O2 consumption than controls (4.93 ± 1.30 vs. 2.93 ± 0.70 ml·kg−1·min−1). After bronchodilation, there was no significant difference in O2 consumption between RAO horses and controls, although there remained evidence of residual airway obstruction. There was a strong correlation between O2 consumption and indexes of airway obstruction. Xylazine sedation was not associated with changes in pulmonary function but did result in markedly decreased REE in controls.