Prediction of stature in the Italian elderly

Adequate quantification of weight and stature is essential in order to determine levels of nutritional support and to monitor the effects of nutritional intervention. Traditional anthropometric techniques are difficult to apply in elderly or handicapped patients chair or bed-bound. The purpose of the present study is to elaborate regression equations for the estimation of stature in the italian elderly population from other anthropometric measures that can be more easily determined. We have found a single model valid for both sexes (in which the value of the variable "sex" equals 0 if woman and 1 if man) to predict stature in italian elderly: Stature = 94.87 + 1.58 knee-height - 0.23 age + 4.8 sex. Cross validation on a control sample of 30 males and 54 females yielded pure errors of 3.1 cm for men and 2.74 cm for women.     

Height and body weight in the elderly. I. A 25-year longitudinal study of a population aged 70 to 95 years

OBJECTIVE: To describe longitudinal changes in height and body weight between the ages of 70 and 95 y. DESIGN: Longitudinal cohort study with representative sample of 70-y-olds. SETTING: Department of Geriatric Medicine, G?teborg University, Sweden. SUBJECTS: 449 males and 524 females, aged 70 y, living in G?teborg were examined in 1971-72 and this study population participated on 11 occasions during a 25-year follow-up. RESULTS: Mean height decreased 4 and 4.9 cm in males and females respectively and the trend was significant between the ages of 70 and 95 y in both sexes. Between 70 and 75 y of age, a significant difference was found between quintiles of body height where in the highest quintile height was lowered by 0.4 and 0. 3 cm/y, in males and females respectively, and in the lowest quintile by 0.1 cm/y in both sexes. Mean body weight decreased 3.2 and 5.1 kg in males and females respectively, from age 70 to 95 y. The trend was significant over 22 and 20 y for males and females, respectively. Between the ages of 70 and 80 y, individuals in highest quintile of body weight decreased at a rate of 0.8 and 0.6 kg/y, three times higher than those in lowest quintile. Due to the decrease in both height and weight over time, body mass index (BMI) was less affected. CONCLUSION: Height, body weight and BMI decreased significantly in both sexes after age 70 y, and there was a gender difference in the trend. The results can be used as reference data for Swedish elderly and might be of importance to the understanding of anthropometry with the ageing process. SPONSORSHIP: See acknowledgements.     

A new predictive equation for resting energy expenditure in healthy individuals

A predictive equation for resting energy expenditure (REE) was derived from data from 498 healthy subjects, including females (n = 247) and males (n = 251), aged 19-78 y (45 +/- 14 y, mean +/- SD). Normal-weight (n = 264) and obese (n = 234) individuals were studied and REE was measured by indirect calorimetry. Multiple-regression analyses were employed to drive relationships between REE and weight, height, and age for both men and women (R2 = 0.71): REE = 9.99 x weight + 6.25 x height - 4.92 x age + 166 x sex (males, 1; females, 0) - 161. Simplification of this formula and separation by sex did not affect its predictive value: REE (males) = 10 x weight (kg) + 6.25 x height (cm) - 5 x age (y) + 5; REE (females) = 10 x weight (kg) + 6.25 x height (cm) - 5 x age (y) - 161. The inclusion of relative body weight and body-weight distribution did not significantly improve the predictive value of these equations. The Harris-Benedict Equations derived in 1919 overestimated measured REE by 5% (p less than 0.01). Fat-free mass (FFM) was the best single predictor of REE (R2 = 0.64): REE = 19.7 x FFM + 413. Weight also was closely correlated with REE (R2 = 0.56): REE = 15.1 x weight + 371.     

Relationships between structural and functional measures of nutritional status in a normally nourished population

BACKGROUND AND AIMS: Both anthropometric and functional measurements have been used in nutritional assessment and monitoring. Hand dynamometry is a predictor of surgical outcome and peak expiratory flow rate has been used as an index of respiratory muscle function. This study aims to measure in normal subjects the relationship between anthropometric measurements, voluntary muscle strength by hand grip dynamometry and respiratory muscle function by peak expiratory flow rate. METHODS: Ninety-eight subjects (46 male, 52 female) with a mean age of 45.9 years were studied. Hand grip strength was measured in the dominant and non-dominant hands with a portable strain-gauge dynamometer. Peak expiratory flow rate was measured using a mini-Wright peak flow meter. Three readings were taken, each 1 min apart, and the average recorded. Midarm muscle circumference (MAMC) was derived from triceps skin fold thickness and midarm circumference (MAC) using standard anthropometric techniques. Statistical relationships were measured with Pearson's coefficient of correlation. RESULTS: In both sexes there was significant correlation between hand grip strength in the dominant and non-dominant hands and peak expiratory flow rate (P<0.001). In men, there was a positive correlation between MAMC, hand grip strength (P<0.001) and peak expiratory flow rate (P<0.001). In women muscle function correlated with height (P<0.001) but not MAMC (P>0.05). CONCLUSIONS: In normal subjects bedside tests of skeletal and respiratory muscle function correlated with each other in both sexes, and with muscle mass in men but not in women.     

Development of bioelectrical impedance analysis prediction equations for body composition with the use of a multicomponent model for use in epidemiologic surveys

BACKGROUND: Previous studies to develop and validate bioelectrical impedance analysis (BIA) equations to predict body composition were limited by small sample sizes, sex specificity, and reliance on reference methods that use a 2-component model. OBJECTIVE: This study was designed to develop sex-specific BIA equations to predict total body water (TBW) and fat-free mass (FFM) with the use of a multicomponent model for children and adults. DESIGN: Data from 5 centers were pooled to create a sample of 1474 whites and 355 blacks aged 12-94 y. TBW was measured by dilution, and FFM was estimated with a multicomponent model based on densitometry, isotope dilution, and dual-energy X-ray absorptiometry. RESULTS: The final race-combined TBW prediction equations included stature(2)/resistance and body weight (R(2) = 0.84 and 0.79 and root mean square errors of 3.8 and 2.6 L for males and females, respectively; CV: 8%) and tended to underpredict TBW in black males (2.0 L) and females (1.4 L) and to overpredict TBW in white males (0.5 L) and females (0.3 L). The race-combined FFM prediction equations contained the same independent variables (R(2) = 0.90 and 0.83 and root mean square errors of 3.9 and 2.9 kg for males and females, respectively; CV: approximately 6%) and tended to underpredict FFM in black males (2.1 kg) and females (1.6 kg) and to overpredict FFM in white males (0.4 kg) and females (0.3 kg). CONCLUSION: These equations have excellent precision and are recommended for use in epidemiologic studies to describe normal levels of body composition.     

Assessment of body composition by bioelectrical impedance in a population aged greater than 60 y

Body composition was measured in a group of 35 healthy men and 37 healthy women aged 60-83 y. Body mass index (BMI) in men was 25.0 +/- 2.2 kg/m2 (means +/- SD) and in women, 25.9 +/- 3.2 kg/m2. BMI was low in relation to body fat percentage as determined by skinfold-thickness measurements or densitometry in comparison with the relation found in younger adults. Mean body fat percentage of the male subjects (aged 70.4 +/- 5.2 y) as determined by densitometry was 31.0 +/- 4.5%, whereas in women (aged 68.0 +/- 5.2 y) it was 43.9 +/- 4.3%. Body impedance correlated with fat-free mass (FFM). The best prediction formulas for the FFM from body impedance and anthropometric variables were 1) FFM (kg) = (0.671 x 10(4) x H2/R) + 3.1S + 3.9 where H is body height (m), R is resistance (omega), and S is gender (females, 0; males, 1) (r = 0.94; SEE = 3.1 kg) and 2) FFM (kg) = (0.360 x 10(4) x H2/R) + 0.359BW + 4.5S - 20T + 7.0 where BW is body weight (kg) and T is thigh circumference (m) (r = 0.96; SEE = 2.5 kg). The prediction equations from the literature, generally determined in younger populations, overestimated FFM in elderly subjects by approximately 6 kg and are not applicable to elderly subjects.     

Weight, body composition and handgrip strength among pulmonary tuberculosis patients: a matched cross-sectional study in Mwanza, Tanzania

This study aimed to estimate deficits in weight, arm fat area (AFA), arm muscle area (AMA) and handgrip strength among smear-positive pulmonary TB (PTB+) patients starting treatment. We conducted a cross-sectional study among PTB+ patients and age- and sex-matched neighborhood controls. HIV status, anthropometric measurements and handgrip strength were determined. Deficits in weight, AFA, AMA and handgrip strength associated with PTB+ and HIV were estimated using multiple regression analysis.We recruited 355 pairs of PTB+ patients and controls. PTB+ was associated with deficits of 10.0 kg (95% CI 7.3; 12.7) in weight and 6.8 kg (95% CI 5.2; 8.3) in handgrip strength among females and 9.1 kg (95% CI 7.3; 10.9) in weight and 6.8 kg (95% CI 5.2; 8.4) in handgrip strength among males. In both sexes, PTB+ was associated with deficits in AFA and AMA. Among females, HIV was associated with deficits in AMA and handgrip strength, but the deficit in handgrip strength was larger among PTB+ patients (3.2 kg 95% CI 1.3; 5.2) than controls (-1.6 kg 95% CI -4.8; 1.5) (interaction, P = 0.009).These findings suggest that deficits in weight and handgrip strength among patients starting TB treatment are severe. Thus, nutritional support may be necessary to ensure reversal of the deficits, and may improve treatment outcomes.     

Relationship of total body fatness and five anthropometric indices in Chinese aged 20-40 years: different effects of age and gender

OBJECTIVES: We aim to evaluate the ethnic-specific relationship of total fat mass and anthropometric indices in Chinese. DESIGN: Cross-section study. SETTING: This study was performed at the College of Life Sciences, Hunan Normal University, P.R. China. SUBJECTS AND METHOD: To increase our understanding of the relationship of total fat mass and anthropometric indices in Chinese, 793 females and 1091 males aged 20-40 years were randomly recruited from Changsha city of P. R. China. Hip circumference (HC) and waist circumference (WC) were measured using standardized equipments, and other three anthropometric indices of body mass index (BMI), waist-to-hip ratio (WHR), and conicity index (CI) were calculated using weight, height, HC and WC. Total body fatness (TBF) in kg was measured using a Hologic QDR 4500 W dual-energy X-ray absorptiometry (DEXA) scanner. RESULTS: There was an increasing trend of TBF, %TBF (percent total body fatness) and the five anthropometric indices in successively older age groups. Compared with females, males generally had high average BMI, WC, HC, WHR and CI, but had low average TBF and %TBF. Except for some correlations in 25-29 years age groups, TBF and %TBF were significantly correlated with five anthropometric indices with the Pearson's correlation coefficients ranging from 0.07 to 0.87. Principal component analysis (PCA) was performed to form four principal components (PCs) that interpreted over 99% of the total variation of the five related anthropometric indices in all age groups, with over 53% of the total variation accounted for by the PC1. Multiple regression analyses showed that four PCs combined explained a greater variance (R (2)=55.2-80.8%) in TBF than did BMI alone (R (2)=40-74.9%). CONCLUSION: Our results suggest that there is an increasing trend of total fat mass and five anthropometric indices with aging; that age and sex have the important effects on influencing the correlations of TBF and the studied anthropometric indices; and that the accuracy of predicting the TBF using five anthropometric indices is higher than using BMI alone.     

Estimating geriatric patient's body weight using the knee height caliper and mid-arm circumference in Hong Kong Chinese

The use of the knee height caliper is a convenient way to estimate a patient's body weight. However, the equation devised to estimate an individual's body weight was specifically designed for Caucasians and Blacks. Therefore, this study is to assess the suitability of the knee height caliper among Chinese geriatric patients residing in Hong Kong. Over a six-month period, all geriatric patients from an acute care hospital and private nursing home in the Kwun Tong were recruited into the study. Only patients/residents that were considered unstable with ascites; low blood pressure; on cardiac monitors or had respiratory difficulties were excluded. Measurements from the knee height caliper and mid-arm muscle circumference of the patients were necessary for estimating their body weights. The actual body weights measured with calibrated bed, chair or portable scales was compared with the calculated body weights from the equation. A comparison of the mean and linear regression was performed for analysis of the results. A total of 300 geriatric patients (200 females and 100 males) were recruited. The mean MAC and knee height results were as follows: 25.1 cm (SD 3.9) for females and 26.2 cm (SD 3.2) for males; and 45.75 cm (SD 2.09) for females and 48.98 cm (SD 2.09) for males respectively. The mean difference among the male group was 0.4222 (95% CI: -0.54, 1.39) with a mean estimated body weight of 58.1 kg (SD 10.1) and a mean actual body weight of 57.7 kg (SD 9.9). The mean difference among the female group was 2.9649 (95% CI: 2.30, 3.63) with a mean estimated body weight of 51.6 kg (SD 10.9) and a mean actual body weight of 48.6 kg (SD 10.1). A new equation devised from the data is as follows: Chinese males (over 60 years of age) (R-square -0.81) Weight = [knee height (cm) x 0.928 + mid-arm circumference (cm) x 2.508 - age (years) x 0.144] - 42.543 +/-9.9kg of actual weight for 95% of Chinese males; Chinese females (over 60 years of age) (R-square - 0.82) Weight (kg) = [knee height (cm) x 0.826 + mid-arm circumference (cm) x 2.116 - age (years) x 0.133] - 31.486 +/-10.1kg of actual weight for 95% of Chinese females. The results showed that the mean estimated body weight calculated from the knee height equation (for Caucasians) was significantly larger than the mean actual body weight for the Chinese subjects. This study suggests that the knee height caliper is a useful tool for estimating the body weights. However, a multi-center study is necessary to validate the new equation for the elderly Chinese population.     

Salt overload in fructose-fed insulin-resistant rats decreases paraoxonase-1 activity

Background

Current validated neonatal body composition methods are limited/impractical for use outside of a clinical setting because they are labor intensive, time consuming, and require expensive equipment. The purpose of this study was to develop an anthropometric model to estimate neonatal fat mass (kg) using an air displacement plethysmography (PEA POD^? Infant Body Composition System) as the criterion.

Methods

A total of 128 healthy term infants, 60 females and 68 males, from a multiethnic cohort were included in the analyses. Gender, race/ethnicity, gestational age, age (in days), anthropometric measurements of weight, length, abdominal circumference, skin-fold thicknesses (triceps, biceps, sub scapular, and thigh), and body composition by PEA POD^? were collected within 1-3 days of birth. Backward stepwise linear regression was used to determine the model that best predicted neonatal fat mass.

Results

The statistical model that best predicted neonatal fat mass (kg) was: -0.012 -0.064*gender + 0.024*day of measurement post-delivery -0.150*weight (kg) + 0.055*weight (kg)² + 0.046*ethnicity + 0.020*sum of three skin-fold thicknesses (triceps, sub scapular, and thigh); R² = 0.81, MSE = 0.08 kg.

Conclusions

Our anthropometric model explained 81% of the variance in neonatal fat mass. Future studies with a greater variety of neonatal anthropometric measurements may provide equations that explain more of the variance.     

Anthropometric predictors of body fat as measured by hydrostatic weighing in Guatemalan adults

BACKGROUND: Most predictive equations currently used to assess percentage body fat (%BF) were derived from persons in industrialized Western societies. OBJECTIVE: We developed equations to predict %BF from anthropometric measurements in rural and urban Guatemalan adults. DESIGN: Body density was measured in 123 women and 114 men by using hydrostatic weighing and simultaneous measurement of residual lung volume. Anthropometric measures included weight (in kg), height (in cm), 4 skinfold thicknesses [(STs) in mm], and 6 circumferences (in cm). Sex-specific multiple linear regression models were developed with %BF as the dependent variable and age, residence (rural or urban), and all anthropometric measures as independent variables (the "full" model). A "simplified" model was developed by using age, residence, weight, height, and arm, abdominal, and calf circumferences as independent variables. RESULTS: The preferred full models were %BF = -80.261 - (weight x 0.623) + (height x 0.214) + (tricipital ST x 0.379) + (abdominal ST x 0.202) + (abdominal circumference x 0.940) + (thigh circumference x 0.316); root mean square error (RMSE) = 3.0; and pure error (PE) = 3.4 for men and %BF = -15.471 + (tricipital ST x 0.332) + (subscapular ST x 0.154) + (abdominal ST x 0.119) + (hip circumference x 0.356); RMSE = 2.4; and PE = 2.9 for women. The preferred simplified models were %BF = -48.472 - (weight x 0.257) + (abdominal circumference x 0.989); RMSE = 3.8; and PE = 3.7 for men and %BF = 19.420 + (weight x 0.385) - (height x 0.215) + (abdominal circumference x 0.265); RMSE = 3.5; and PE = 3.5 for women. CONCLUSION: These equations performed better in this developing-country population than did previously published equations.     

Anthropometric measurements in the elderly: age and gender differences

In clinical practice and epidemiological surveys, anthropometric measurements represent an important component of nutritional assessment in the elderly. The anthropometric standards derived from adult populations may not be appropriate for the elderly because of body composition changes occurring during ageing. Specific anthropometric reference data for the elderly are necessary. In the present study we investigated anthropometric characteristics and their relationship to gender and age in a cross-sectional sample of 3,356 subjects, randomly selected from an elderly Italian population. In both sexes, weight and height significantly decreased with age while knee height did not. The BMI was significantly higher in women than in men (27.6 SD 5.7 v. 26.4 SD 3.7; P<0.001) and it was lower in the oldest than in the youngest subjects (P<0.05) of both genders. The 75th year of age was a turning point for BMI as for other anthropometric measurements. According to BMI values, the prevalence of malnutrition was lower than 5 % in both genders, whereas obesity was shown to have a higher prevalence in women than in men (28% v. 16%; P<0.001). Waist circumference and waist: hip ratio values were higher for the youngest men than for the oldest men (P<0.05), whereas in women the waist: hip ratio values were higher in the oldest women, suggesting that visceral redistribution in old age predominantly affects females. In conclusion, in the elderly the oldest subjects showed a thinner body frame than the youngest of both genders, and there was a more marked fat redistribution in women.     

Effect of an oral contraceptive containing 30 microg ethinylestradiol plus 3 mg drospirenone on body composition of young women affected by premenstrual syndrome with symptoms of water retention

PURPOSE: This study was conducted to evaluate body weight and composition during oral contraception with 30 microg ethinylestradiol plus 3 mg drospirenone (30EE+DRSP) in women affected by premenstrual syndrome (PMS) with somatic symptoms related to water retention. DESIGN: This prospective study was performed using multifrequency bioelectrical impedance analysis in 18 normally cycling PMS patients (mean age, 28.8 years) evaluated at baseline, during the luteal phase of the menstrual cycle and after 3 and 6 cycles of 30EE+DRSP. Total body water (TBW), intracellular water (ICW), extracellular water (ECW), fat mass and fat-free mass were evaluated. Body weight, waist-to-hip ratio and blood pressure were also determined at each visit. Basal values were compared with those measured in 31 healthy females without PMS (controls). RESULTS: PMS patients have higher levels of TBW and ICW than controls. After 6 months of 30EE+DRSP, TBW and ECW were significantly lower than before treatment. No significant variations in ICW or in the other parameters were observed. CONCLUSION: In women with PMS, 30EE+DRSP reduces the concentrations in TBW and ECW. This effect is likely due to the antimineralocorticoid activity of DRSP. Whether these changes may account for the improvement of premenstrual fluid-related symptoms reported with this formulation is discussed.     

Estimation of total-body and limb muscle mass in hemodialysis patients by using multifrequency bioimpedance spectroscopy

BACKGROUND: Skeletal muscle mass can be measured noninvasively with magnetic resonance imaging (MRI), but this is time-consuming and expensive. OBJECTIVE: We evaluated the use of multifrequency bioimpedance spectroscopy (BIS) measurements of intracellular volume (ICV) to model total-body skeletal muscle mass (TBMM) and limb skeletal muscle mass in hemodialysis patients. DESIGN: TBMM was measured by MRI in 20 male and 18 female hemodialysis patients with a median (range) age of 54 y (33-73 y), weight of 78.9 kg (43.2-120 kg), and body mass index (BMI; in kg/m2) of 27.3 (19.4-46.6). We measured total body water (TBW) by using D2O dilution, extracellular volume (ECV) as bromide space, and ICV as TBW minus bromide space. Total body potassium (TBK) measured as 40K was used as an independent model of TBMM. BIS was used to measure whole-body TBW (ankle to wrist) and TBW in the arms and legs. BIS-estimated ICV was used to construct models to calculate limb muscle mass and TBMM. The latter was compared with models derived from isotopic methods. RESULTS: BIS yielded a model for TBMM [TBMM = 9.52 + 0.331 x ICV + 2.77 (male) + 0.180 x weight (kg) - 0.133 x age] (R2 = 0.937, P < 0.0001) as precise as TBK-measured TBMM [TBMM = 1.29 + 0.00453 x TBK (mEq) + 1.46 (male) + 0.144 x weight (kg) - 0.0565 x age] (R2 = 0.930, P < 0.0001) or isotopic methods. BIS models were also developed for measuring leg and arm muscle mass. CONCLUSION: BIS provides an estimate of TBMM that correlates well with isotopic methods in approximating values obtained by MRI and can be used to estimate limb muscle mass.     

Estimation of body fatness from body mass index and bioelectrical impedance: comparison of New Zealand European, Maori and Pacific Island children

OBJECTIVE: To compare percentage body fat (%BF) for a given body mass index (BMI) among New Zealand European, Maori and Pacific Island children. To develop prediction equations based on bioimpedance measurements for the estimation of fat-free mass (FFM) appropriate to children in these three ethnic groups. DESIGN: Cross-sectional study. Purposive sampling of schoolchildren aimed at recruiting three children of each sex and ethnicity for each year of age. Double cross-validation of FFM prediction equations developed by multiple regression. SETTING: Local schools in Auckland. SUBJECTS: Healthy European, Maori and Pacific Island children (n=172, 83 M, 89 F, mean age 9.4+/-2.8(s.d.), range 5-14 y). MEASUREMENTS: Height, weight, age, sex and ethnicity were recorded. FFM was derived from measurements of total body water by deuterium dilution and resistance and reactance were measured by bioimpedance analysis. RESULTS: For fixed BMI, the Maori and Pacific Island girls averaged 3.7% lower %BF than European girls. For boys a similar relation was not found since BMI did not significantly influence %BF of European boys (P=0.18). Based on bioimpedance measurements a single prediction equation was developed for all children: FFM (kg)=0.622 height (cm)(2)/resistance+0.234 weight (kg)+1.166, R(2)=0.96, s.e.e.=2.44 kg. Ethnicity, age and sex were not significant predictors. CONCLUSIONS: A robust equation for estimation of FFM in New Zealand European, Maori and Pacific Island children in the 5-14 y age range that is more suitable than BMI for the determination of body fatness in field studies has been developed.     

博山地区4780名成年人身高、体重调查及体重指数、肥胖发生率的统计分析(人群肥胖症研究之一)

作者采用较准确的方法,对博山地区20岁以上不同职业的4780人(男3216,女1564),进行了年龄、身高和体重的调查,并对调查结果作了性别、年龄、身高与体重之问关系的相关、回归分析,得出推算标准体重的回归方程式、“正常成年男女身高与体重表”。按公式计算出体重指数,并拟定了20岁以上男女体重指数的正常范围(男0.1933～0.2525,女0.1951～0.2563)和体重超重、肥胖的体重指数界限值。按这个体重指数标准,本次调查结果男性属超重者占7.71％,肥胖占5.22％;女性超重占6.96％,肥胖占4.73％。本调查资料所载博山地区20岁以上人群年龄、身高与体重之间的关系及推算标准体重的方法,对国内其它地区也会有一定参考价值。     

Body composition in patients with short bowel syndrome: an assessment by bioelectric impedance spectroscopy (BIS) and dual-energy absorptiometry (DXA)

OBJECTIVE: To describe body composition in patients with short bowel syndrome (SBS) by using bioelectric impedance spectroscopy (BIS), dual-energy X-ray absorptiometry (DXA) measurements and anthropometrical-derived estimates. SUBJECTS: In all, 19 patients were included, mean age 54 y, range 36-77 (F/M=11/8). Mean BMI was 21.5 kg/m(2). Eight patients were on home parenteral nutrition (HPN). METHODS: Total body water (TBW), intracellular water and extracellular water were assessed by BIS. TBW were derived from DXA. Fat-free mass (FFM) was assessed by BIS and DXA. TBW and FFM were predicted according to an empirical formula. Differences were analysed using the Bland-Altman method. RESULTS: The mean difference between TBW (DXA) and TBW (BIS) was -1.1 l in women and -1.8 l in men. For FFM, the mean difference between FFM (DXA) and FFM (BIS) was -1.7 kg in women and -2.5 kg in men. The mean difference between TBW (DXA) and TBW (BIS) for all patients was -1.2 l and limits of agreement were (-7.80-5.40). Hydration of FFM assessed by BIS gave a mean of 0.75 (0.08). CONCLUSION: The limits of agreement (Bland-Altman) between DXA and BIS were wide, indicating that methods are not interchangeable, which limits its clinical utility. Most of our patients with SBS were maintained in a stable clinical condition within normal limits of body weight and BMI. FFM and TBW did not appear to be altered in ileostomates or those on HPN.     

Comparison of isotope dilution with bioimpedance spectroscopy and anthropometry for assessment of body composition in asymptomatic HIV-infected and HIV-uninfected breastfeeding mothers

BACKGROUND: The effect of breastfeeding on the nutrition of HIV-infected (HIV+) mothers is unknown. Simple, valid methods are needed for body-composition assessment of HIV+ women. OBJECTIVE: We compared the ability of bioimpedance spectroscopy (BIS) and anthropometry with that of isotope dilution (2H2O) to measure fat-free mass (FFM) and fat mass (FM) in HIV+ and HIV-uninfected (HIV-) breastfeeding South African mothers. DESIGN: Total body water (TBW) content of 68 lactating mothers (20 HIV+, 48 HIV-) was measured 10 wk after delivery by using BIS and 2H2O to measure FFM and FM. Anthropometric measurements included body mass index (BMI; in kg/m2), midupper arm circumference (MUAC), and 4 skinfold thicknesses. RESULTS: TBW, FFM, and FM measurements determined by BIS were correlated with 2H2O measurements in HIV+ (r = 0.664, 0.621, and 0.872, respectively; P < 0.01) and HIV- (r = 0.876, 0.868, and 0.932, respectively; P < 0.001) mothers. TBW measured by BIS was greater than that measured by the 2H2O method in both HIV+ (1.8 L) and HIV- (1.5 L) women; FM or FFM did not differ significantly by method. BMI, MUAC, and all skinfold-thickness measurements correlated strongly (r > 0.62, P < 0.001) with FM measured by 2H2O in both groups. BMI and MUAC correlated (r > 0.64, P < 0.001) with FFM in HIV- mothers but not in HIV+ mothers. CONCLUSIONS: In HIV+ and HIV- breastfeeding mothers, BIS provides an estimate of body composition comparable to that obtained with the 2H2O method. BMI and MUAC are useful in predicting FM in both groups but are not valid measures of FFM in HIV+ mothers.     

Body composition obtained from the body mass index

Background  Since obesity and related diseases are now considered epidemic, new and more accurate formulas for epidemiological studies are of interest to the scientific community. Several equations have been proposed to estimate the body composition simply from anthropometric measurements. However, with time, the body composition of the populations studied changes in relation to their food habits and lifestyle, and, therefore, the equations must be regularly updated and corrected. Aim of the study  The aim of the study was to develop new equations to determine the body composition among the Italian population using the body mass index and independently by variables such as age and body structure. Methods  Bioelectrical impedance and anthropometric analysis of 764 Italian Caucasian subjects (342 females and 422 males), 11 to 80 years of age, were analysed. Females and males were analysed separately. Multiple regression analyses were performed in order to estimate the body composition of the subjects. The estimated masses were then compared with the measured masses using Bland and Altman plots. We also calculated the differences between the estimated and measured masses, reported as % of the body weight, for the 95, 85 and 75° percentile of the female and male groups. Finally we compared our formulas with the Watson equations, which are used to estimate the total body water. Results  All body masses estimated were positively correlated to the measured values. Moreover, at any percentile analysed, our formulas resulted more precise than the Watson formula. Equations: Females: FM = 1.9337 BMI – 26.422; FFM = BW – FM; BCM = 0.3655 FFM + 4.865; TBW = 0.5863 FFM + 7.1732; Males: FM = 1.407 BMI – 21.389; FFM = BW – FM; BCM = 0.4485 FFM + 3.3534; TBW = 0.6997 + 1.4567. Conclusions  Although an inevitable inaccuracy must be expected in epidemiological studies, our equations are adequate to analyze the body composition state and changes occurring among the Italian population by simply considering weight and height.