Longitudinal follow-up of body composition in hematopoietic stem cell transplant patients.

Patients with hematological malignancies are well nourished prior to allogeneic hematopoietic stem cell transplantation (HSCT). HSCT and associated complications can affect body composition. The study evaluated cross-sectionally the prevalence and longitudinally the changes in lean body mass index (LBMI) in HSCT patients. Patients (n=82) were classified as normal or low LBMI. Logistic regression analyses were used to estimate odds ratios (OR) for low vs normal LBMI, between healthy volunteers and patients; for limited or extensive vs no chronic graft-versus-host-disease (GVHD); and for decreased (Karnofsky <80) vs normal functional status (>80). Patients were significantly more likely to have low LBMI at 6, 12 months, 2-3, 4-6 and >6 years than volunteers. In all, 38% of patients were below pre-HSCT LBMI at 4-6 years post-HSCT. Low LBMI was significantly associated with steroid treatment (OR 2.6, confidence intervals (CI) 1.3-5.2, P=0.008); limited (OR 5.5, CI 1.7-18.5, P=0.005) or extensive chronic GVHD (OR 20.3, CI 5.7-71.6, P<0.001); and decreased performance status (Karnofsky scores of < or =80) (OR 2.7, CI 1.3-5.9, P=0.01). Patients were more likely to have low LBMI than volunteers. Chronic GVHD and low performance status were associated with low LBMI; thus, complications and/or treatment increase the likelihood of low LBMI.

Body composition during growth in children: limitations and perspectives of bioelectrical impedance analysis.

There are a number of differences between the body composition of children and adults. Body composition measurements in children are inherently challenging, because of the rapid growth-related changes in height, weight, fat-free mass (FFM) and fat mass (FM), but they are fundamental for the quality of the clinical follow-up. All body composition measurements for clinical use are 'indirect' methods based on assumptions that do not hold true in all situations or subjects. The clinician must primarily rely on two-compartment models (that is, FM and FFM) for routine determination of body composition of children. Bioelectrical impedance analysis (BIA) is promising as a bedside method, because of its low cost and ease of use. This paper gives an overview of the differences in body composition between adults and children in order to understand and appreciate the difference in body composition during growth. It further discusses the use and limitations of BIA/bioelectrical spectroscopy (BIA/BIS) in children. Single-frequency and multi-frequency BIA equations must be refined to better reflect the body composition of children of specific ethnicities and ages but will require development and cross-validation. In conclusion, recent studies suggest that BIA-derived body composition and phase angle measurements are valuable to assess nutritional status and growth in children, and may be useful to determine baseline measurements at hospital admission, and to monitor progress of nutrition treatment or change in nutritional status during hospitalization.

Total body mass, fat mass, fat-free mass, and skeletal muscle in older people: cross-sectional differences in 60-year-old persons.

OBJECTIVES: To evaluate body composition parameters, including fat-free mass (FFM), appendicular skeletal muscle mass (ASMM), relative skeletal muscle mass (RSM) index, body cell mass (BCM), BCM index, total body potassium (TBK), fat mass, percentage fat mass (FM), and their differences between age groups and to evaluate the frequency of sarcopenia in healthy older subjects DESIGN: Cross-sectional, nonrandomized study. SETTING: Outpatient clinic. PARTICIPANTS: Ninety-one healthy men and 100 healthy women age 60 and older. MEASUREMENTS: FFM, ASMM, FM, and percentage fat mass by whole-body dual-energy x-ray absorptiometry; TBK, BCM, and TBK/FFM ratio by whole body potassium-40 counter. RESULTS: All lean body mass parameters were significantly (P <.05) lower in subjects age 80 and older than in those age 70 to 79, except ASMM in women. Mean FFM was 4.2 kg (7.3%) lower in men age 80 and older than in those younger than 70 and 2.9 kg (6.8%) lower in women age 80 and older than in those younger than 70. The skeletal muscle mass, reflected by ASMM, decreased more than FFM. This suggests that nonskeletal muscle mass is proportionally preserved during aging. Forty-five percent of men and 30% of women were sarcopenic by definition of BCM index and 11.0% of men and women by definition of RSM index. CONCLUSIONS: Significant age-related differences exist in body composition of older men and women between age 60 and 95. The greater decrease in TBK and BCM than the decrease in FFM and skeletal muscle mass suggests changing composition of FFM with age. Lack of agreement between two independent sarcopenia indexes suggests that further refinement in the definition of a sarcopenia index is necessary.

Validation of a bioelectrical impedance analysis equation to predict appendicular skeletal muscle mass (ASMM).

RATIONALE: Appendicular skeletal muscle mass (ASMM) is useful in the evaluation of nutritional status because it reflects the body muscle protein mass. The purpose of this study was to validate, against dual-energy X-ray absorptiometry (DEXA), a BIA equation to predict ASMM to be used in volunteers and patients. METHOD: Healthy men (n = 246 men, BMI 25.3+/-2.9 kg/m(2)) and women (n =198, 24.1+/-3.6 kg/m(2)), and heart, lung and liver transplant patients (213 men, BMI of 24.6+/-4.4 kg/m(2); 113 women, BMI 23.0+/-5.2 kg/m(2)) were measured by BIA (Xitron Technologies) and DEXA (Hologic QDR 4500). A BIA equation to predict ASMM (kg) that included height(2)/resistance, weight, gender, age and reactance, was developed by means of multiple regressions. [table: see text] Mean difference (Bland-Altman) for volunteers was 0.1+/-1.1 kg, r =0.95, SEE 1.12 kg and for patients -0.4+/-1.5 kg, r =0.91, SEE 1.5 kg. Best fitted multiple regression equation was -4.211 + (0.267 x height2 / resistance) + (0.095 x weight)+(1.909 x sex (men = 1, women = 0)) + (-0.012 x age) + (0.058 x reactance). CONCLUSIONS: BIA permits the prediction of ASMM in healthy volunteers and patients between 22 and 94 years of age. A slightly larger, though clinically not significant, error was noted in patients.

Energy expenditure in anorexia nervosa: can fat-free mass as measured by bioelectrical impedance predict energy expenditure in hospitalized patients?

Anorexia nervosa (AN) is associated with a reduced metabolically active fat-free mass (FFM) and basal metabolic rate (BMR). Excessive refeeding results in major fat deposition which is not well tolerated by patients. Prediction of BMR is, therefore, a clinical issue during refeeding, but measurement by indirect calorimetry is time-consuming and not widely available. The study aim was to determine if and when BMR could be estimated from prediction formulas based on FFM derived from bioelectrical impedance analysis (BIA) in AN patients during refeeding. Indirect calorimetry and BIA were prospectively measured bi-weekly in 9 AN patients (body mass index 13.7 +/- 0.5 kg/m2) for 10 weeks of refeeding. Initial BMR was 969 +/- 46.7 kcal/d and 27.7 +/- 1.4 kcal/kg FFM, and at week 10 increased to 1360 +/- 44.6 kcal/d and 35.8 +/- 0.8 kcal/kg FFM. While correlations improved with increasing weight, FFM and body mass index, prediction formulas are insufficient to permit prediction of BMR based on weight or FFM, even after 10 weeks of refeeding. To allow for optimal nutritional support, indirect calorimetry measurements may be useful in the early weeks of refeeding because of a large variability of basal metabolic rate between patients.

Food intake in 1707 hospitalised patients: a prospective comprehensive hospital survey.

BACKGROUND & AIMS: This study aimed to assess the ability of the hospital meal service to meet patients' nutritional needs. METHODS: All hospitalised patients who received 3 meals/day without artificial nutritional support were included. The nutritional values of food served, consumed and wasted during a 24 h period were compared to patients' needs estimated as energy: 110% Harris-Benedict formula; protein: 1.2 or 1.0 g/kg bodyweight/day for patients < or = or > 65 years old, respectively. A structured interview recorded patients' evaluation of the meal quality, their reasons for non-consumption of food and the relationship between food intake and disease. RESULTS: Out of 1707 patients included, 1416 were fully assessable (59% women; 68+/-21 years; body mass index: 24.3+/-5.1 kg/m(2)). Daily meals provided 2007+/-479 kcal and 78+/-21 g of protein and exceeded patients' needs by 41% and 15%, respectively. However, 975 patients did not eat enough. Plate waste was 471+/-372 kcal and 21+/-17 g of protein/day/patient. Moreover, the food intake of 572 (59%) of these underfed patients was not predominantly affected by disease. Logistic regression analyses identified as other risk factors: elevated BMI, male gender, modified diet prescription, length of stay <8 or > or = 90 days and inadequate supper. CONCLUSION: Despite sufficient food provision, most of the hospitalised patients did not cover their estimated needs. Since insufficient food intake was often attributed to causes other than disease, there should be potential to improve the hospital meal service.

Prevalence of malnutrition in 1760 patients at hospital admission: a controlled population study of body composition.

OBJECTIVE: Malnutrition, defined as low or excessive body weight, is associated with increased hospital length of stay and cost of care. The purpose of this study was to determine if fat-free mass (FFM) and body fat (BF) differed between patients at hospital admission in Geneva and Berlin and healthy volunteers, and if there is a difference in the prevalence of low FFM (percentile P<10) and high BF (percentile P>90) between patients and volunteers. METHODS: In total, 1760 patients (Geneva: 525 men, 470 women; Berlin: 397 men, 368 women) were evaluated for malnutrition by BMI, serum albumin, and FFM and BF, determined by bioelectrical impedance analysis (BIA), and compared to 1760 healthy volunteers matched for age and height, and further compared to FFM and BF percentiles, previously determined in 5225 healthy adults. RESULTS: The prevalence of FFM P<10 was greater in patients than controls. The prevalence of albumin<35 g/l (14.9% and 11.2% in Geneva and Berlin patients, respectively) and BMI<20.0 kg/m(2) was lower than the prevalence of low FFM (31.3% and 17.3%, respectively). The prevalence of high BF in Berlin patients was three-fold the prevalence of volunteers. Twelve and twenty percent of Geneva and Berlin patients, respectively, with normal BMI had high BF, compared to 4% of volunteers. CONCLUSIONS: Geneva and Berlin patients had lower FFM and higher BF than age-and height-matched volunteers and a higher prevalence of low FFM and high BF. Serum albumin and BMI underestimated the prevalence of malnutrition in patients at hospital admission. Body composition measurements identified patients with low FFM and low or high BF reserves.

Physical activity and fat-free and fat mass by bioelectrical impedance in 3853 adults.

OBJECTIVE: To determine the effects of regular physical activity on body composition, as measured by bioelectrical impedance analysis (BIA), in a large Caucasian population of healthy subjects between 15 and 64 yr of age, and to observe the cross-sectional changes in body composition with increasing age. DESIGN: Cross-sectional comparison between sedentary and physically active adults (at least 3 h x wk(-1) at moderate or hard intensity level activity) during aging. SUBJECTS: A total of 3853 healthy adults (1036 sedentary and 1019 physically active men, and 1280 sedentary and 518 physically active women) between 15 and 64 yr of age. MEASUREMENTS: Height, weight, body mass index (BMI), and fat-free mass (FFM), fat mass, and % fat mass measured by 50-kHz BIA. RESULTS: Higher weight in older sedentary adults was due to a higher fat mass. In 55- to 64-yr-olds compared with 25- to 34-yr-olds, fat mass was 5.5 kg (P < 0.0001) higher in sedentary and 0.6 kg (P < 0.3) higher in physically active men, and 4.5 kg (P < 0.0001) and 2.0 kg (P < 0.04) higher in sedentary and physically active women, respectively. Physical activity was able to limit fat mass and weight gain in men over 25 yr of age and in women until 54 yr of age. Endurance type physical activity was not associated with increased FFM. For the same BMI, sedentary men and women have < 0.7 kg (P < 0.001) higher fat mass than physically active men and women. CONCLUSION: Therefore, the benefits of physical activity seem to include maintenance or prevention of an increase of BMI that in turn correlates with prevention of a fat mass increase for physically active subjects.

Body composition by x-ray absorptiometry and bioelectrical impedance in female runners.

Body composition interests athletes since athletic performance is influenced by and dependent on the proportion and total amount of fat-free mass (FFM) and fat mass. The use of bioelectrical impedance (BIA) has increased recently since portable instruments make the measurements easy to execute and relatively inexpensive. The purpose of this study was to test the degree of relationship between FFM and fat mass calculated in elite female runners with 12 different BIA formulas reported in the literature and measured by dual-energy x-ray absorptiometry (DXA). The present study shows that body composition by BIA is valid in female runners. Prediction equations used to calculate FFM and fat mass must be appropriate for this population subgroup and validated against other methods, such as DXA and hydrodensitometry. Those formulas that performed well in the controls gave poor results in the female runner and vice versa. The below average fat mass noted in female runners suggests that prediction equations for untrained women with average fat mass are inappropriate. The formula by RJL Systems-2 for women: FFM = 5.091 + 0.6483.height2/resistance + 0.1996.weight gave best predictions of FFM in female runners. Further research is necessary to validate BIA prediction formulas in other athletes.

Age-related differences in fat-free mass, skeletal muscle, body cell mass and fat mass between 18 and 94 years.

OBJECTIVE: To determine (1) lean and fat body compartments, reflected by fat-free mass (FFM), appendicular skeletal muscle mass (ASMM), body cell mass (BCM), total body potassium (TBK), fat mass and percentage fat mass, and their differences between age groups in healthy, physically active subjects from 18 to 94 y of age; and (2) if the rate of decrease in any one of the parameters by age might be accelerated compared to others. METHODS: A total of 433 healthy ambulatory Caucasians (253 men and 180 women) aged 18--94 y were measured by dual-energy X-ray absorptiometry (DXA) and whole body scintillation counter (TBK counter) using a large sodium iodide crystal (203 mm diameter). RESULTS: The ASMM change (-16.4 and -12.3% in men and women, respectively) in >75 y-old compared to 18 to 34-y-old subjects was greater than the FFM change (-11.8 and -9.7% in men and women, respectively) and this suggests that skeletal muscle mass decrease in older subjects was proportionally greater than non-skeletal muscle mass. BCM (-25.1 and -23.2% in men and women, respectively) and TBK differences were greater than the differences in FFM or ASMM suggesting altered composition of FFM in older subjects. Women had lower peak FFM, ASMM, BCM and TBK than men. CONCLUSIONS: The decline in FFM, ASMM, BCM and TBK is accelerated in men and women after 60 y of age and FFM, ASMM, BCM and TBK are significantly lower than in younger subjects. Fat mass continued to increase until around 75 y.

Fat-free mass in chronic illness: comparison of bioelectrical impedance and dual-energy x-ray absorptiometry in 480 chronically ill and healthy subjects.

Assessment of fat-free mass (FFM) and fat mass in ambulatory and hospitalized patients permits optimal adaptation of nutrition support. Recent methods for the determination of FFM are dual-energy x-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA). The purpose of this study was to determine if the BIA-determined FFM as estimated by the formula by Kotler et al. and the Geneva formula could be validated when compared to DXA-determined FFM in subjects with various diagnoses. Body composition was measured by BIA and DXA in 480 subjects including healthy young men and women, elite female runners, and patients with various pathologies (including chronic obstructive and restrictive pulmonary disease patients; cystic fibrosis patients; lung, heart, and liver transplantation patients [both pre- and post-], and hemiplegic and AIDS patients). The present results suggest that BIA is relevant in the clinical assessment of body composition, but BIA formulas appropriate to the subject pool must be used for evaluation of FFM and fat mass. The BIA formula by Kotler et al. is appropriate for healthy subjects and patients with AIDS, cystic fibrosis, and pre- or postliver transplantation. The Geneva formula is more appropriate in pulmonary diseases and hemiplegic subjects with normal weight.

Fat-free and fat mass percentiles in 5225 healthy subjects aged 15 to 98 years.

OBJECTIVES: Fat-free mass (FFM) and fat mass (FM) are important in the evaluation of nutritional status. Bioelectrical impedance analysis (BIA) is a simple, reproducible method used to determine FFM and FM. Because normal values for FFM and FM have not yet been established in adults aged 15 to 98 y, its use is limited in the evaluation of nutritional status. The aims of this study were to determine reference values for FFM, FM, and percentage of FM by BIA in a white population of healthy adults, observe their differences with age, and develop percentile distributions for these parameters between ages 15 and 98 y. METHODS: Whole-body resistance and reactance of 2735 healthy white men and 2490 healthy white women, aged 15 to 98 y, was determined by 50-kHz BIA, with four skin electrodes on the right hand and foot. FFM and FM were calculated by a previously validated, single BIA formula and analyzed for age decades. RESULTS: Mean FFM peaked in 35- to 44-y-old men and 45- to 54-y-old women and declined thereafter. Mean FFM was 8.9 kg or 14.8% lower in men older than 85 y than in men 35 to 44 y old and 6.2 kg or 14.3% lower in women older than 85 y than in women 45 to 54 y old. Mean FM and percentage of FM increased progressively in men and women between ages 15 and 98 y. The results suggested that the greater weight noted in older subjects is due to larger FM. CONCLUSIONS: The percentile data presented serve as reference to evaluate deviations from normal values of FFM and FM in healthy adult men and women at a given age.

Reference values of fat-free and fat masses by bioelectrical impedance analysis in 3393 healthy subjects.

Determination of fat-free mass (FFM) and fat mass (FM) is of considerable interest in the evaluation of nutritional status. In recent years, bioelectrical impedance analysis (BIA) has emerged as a simple, reproducible method used for the evaluation of FFM and FM, but the lack of reference values reduces its utility to evaluate nutritional status. The aim of this study was to determine reference values for FFM, FM, and %FM by BIA in a white population of healthy subjects, to observe the changes in these values with age, and to develop percentile distributions for these parameters. Whole-body resistance of 1838 healthy white men and 1555 women, aged 15-64 y, was determined by using four skin electrodes on the right hand and foot. FFM and FM were calculated according to formulas validated for the subject groups and analyzed for age decades. This is the first study to present BIA-determined age- and sex-specific percentiles for FFM, FM, and %FM for healthy subjects, aged 15-64 y. Mean FM and %FM increased progressively in men and after age 45 y in women. The results suggest that any weight gain noted with age is due to a gain in FM. In conclusion, the data presented as percentiles can serve as reference to evaluate the normality of body composition of healthy and ill subject groups at a given age.

Single prediction equation for bioelectrical impedance analysis in adults aged 20--94 years.

Existing equations for bioelectrical impedance analysis (BIA) are of limited use when subjects age or become overweight because these equations were developed in young, normal-weight subjects and are not valid in elderly or overweight people. The purpose of this study was to validate a single BIA equation in healthy white subjects aged 22--94 y with a body mass index between 17.0 and 33.8 kg/m(2). Healthy subjects (202 men and 141 women) aged 20--94 y were measured by two methods: fat-free mass (FFM) was measured by dual-energy x-ray absorptiometry (Hologic QDR-4500) and by a bioelectrical impedance analyzer (Xitron 4000B). Validity of BIA was assessed by double cross validation. Because correlations were high (r = 0.986--0.987) and prediction errors low, a single equation was developed using all subjects, as follows: FFM = -4.104 + (0.518 x height(2)/resistance) + (0.231 x weight) + (0.130 x reactance) + (4.229 x sex: men = 1, women = 0). FFM predicted with dual-energy x-ray absorptiometry was 54.0 +/- 10.7 kg. BIA-predicted FFM was 54.0 +/- 10.5 kg (r = 0.986, standard error of the estimate = 1.72 kg, technical error = 1.74 kg). In conclusion, the new Geneva BIA equation was valid for prediction of FFM in healthy adults aged 22--94 y with body mass indexes between 17.0 and 33.8 kg/m(2). Inclusion of reactance in the single prediction equation appeared to be essential for use of BIA equations in populations with large variations in age or body mass.

Body composition by X-ray absorptiometry and bioelectrical impedance in chronic respiratory insufficiency patients.

Nutrition assessment is important during chronic respiratory insufficiency to evaluate the level of malnutrition or obesity and should include body composition measurements. The appreciation of fat-free and fat reserves in patients with chronic respiratory insufficiency can aid in designing an adapted nutritional support, e.g., nutritional support in malnutrition and food restriction in obesity. The purpose of the present study was to cross-validate fat-free and fat mass obtained by various bioelectric impedance (BIA) formulas with the fat-free and fat mass measured by dual-energy X-ray absorptiometry (DXA) and determine the formulas that are best suited to predict the fat-free and fat mass for a group of patients with severe chronic respiratory insufficiency. Seventy-five patients (15 women and 60 men) with chronic obstructive and restrictive respiratory insufficiency aged 45-86 y were included in this study. Body composition was calculated according to 13 different BIA formulas for women and 12 for men and compared with DXA. Because of the variability, calculated as 2 standard deviations, of +/- 5.0 kg fat-free mass for women and +/- 6.4 kg for men for the best predictive formula, the use of the various existing BIA formulas was considered not clinically relevant. Therefore disease-specific formulas for patients with chronic respiratory insufficiency should be developed to improve the prediction of fat-free and fat mass by BIA in these patients.

Reliable bioelectrical impedance analysis estimate of fat-free mass in liver, lung, and heart transplant patients.

BACKGROUND: Bioelectrical impedance analysis (BIA) can be valuable in evaluating the fat-free (FFM) and fat masses (FM) in patients, provided that the BIA equation is valid in the subjects studied. The purpose of the clinical evaluation was to evaluate the applicability of a single BIA equation to predict FFM in pre- and posttransplant patients and to compare FFM and FM in transplant patients with healthy controls. METHODS: Pre- and posttransplant liver, lung, and heart patients (159 men, 86 women) were measured by two methods-50-kHz BIA-derived FFM (FFM(BIA)) by Xitron instrument and DXA-derived FFM (FFM(DXA)) by Hologic QDR-4500 instrument-and compared with healthy controls (196 men, 129 women), aged 20 to 79 years. RESULTS: The high correlation coefficient (r = .974), small bias (0.3 +/- 2.3 kg), and small SEE (2.3 kg) suggest that BIA using the GENEVA equation is able to predict FFM in pre- and posttransplant patients. The study shows that the lower weight seen in transplant men and women than in controls was due to lower FFM, which was partially offset by higher FM in men but not in women. Furthermore, the higher weights in posttransplant than in pretransplant patients were due to higher FM and % FM that was confirmed by lower FFM/FM ratio in posttransplant patients. CONCLUSIONS: Single 50-kHz frequency BIA permits measurement of FFM in pre- and posttransplant patients.

Fat-free mass change to weight change ratio during refeeding following lung transplantation.

Malnutrition occurs frequently prior to lung transplantation (LTR), but patients gain weight after LTR. The study aimed to determine the ratio changes of fat-free mass (deltaFFM): changes of body weight (deltaBW) during refeeding. A total of 37 LTR patients were measured for weight and FFM and body fat by bioimpedance analysis at 1 month post-LTR, then annually for 3 years. Linear regressions determined the ratio deltaFFM:deltaBW during refeeding. DeltaFFM was: year- 1=1.822+0.389* deltaBW, r(2)=0.397; yr-2=0.611+0.246* deltaBW, r(2)=0.441; yr-3=-0.17+0.208 * deltaBW, r(2)=0.319. Refeeding during year-1 in thin subjects resulted in a ratio deltaFFM:deltaBW of 0.389, whereas the change in ratio deltaFFM:deltaBW during year- 2 and 3 was 0.246 and 0.208, respectively. Refeeding resulted in a larger ratio deltaFFM:deltaBW in thin subjects versus normal and overweight subjects. Thus, refeeding in underweight LTR patients is geared to normalizing depleted FFM, whereas later FFM gains were similar to FFM gains in normal and overweight subjects.

Prevalence of low fat-free mass index and high and very high body fat mass index following lung transplantation.

The aim of this study was to determine the prevalence of low fat-free mass index (FFMI) and high and very high body fat mass index (BFMI) after lung transplantation (LTR). A total of 37 LTR patients were assessed prior to and at 1 month, 1 year and 2 years for FFM and compared to 37 matched volunteers (VOL). FFM was calculated by the Geneva equation and normalized for height (kg/m(2)). Subjects were classified as FFMI "low", 8.2 kg/m(2) in men and >11.8 kg/m(2) in women. In 23 M/14 F, body mass index (BMI) was 22.3+/-4.4 and 20.1+/-4.9 kg/m(2), respectively. The prevalence of low FFMI was 80% at 1 month and 33% at 2 years after LTR. Prevalence of very high BFMI increased and was higher in patients than VOL after LTR. The prevalence of low FFMI was high prior to and remained important 2 years after LTR, whereas BFMI was lower prior to and higher 2 years after LTR.