Changes in bioimpedance analysis after stable refeeding of undernourished anorexic patients

Muscle Mass and Vitamin B6 Are Linked to Negative Body Image in Women with Anorexia Nervosa: A Retrospective Study

INTRODUCTION

Anorexia nervosa severely impacts the physical body and mental body (i.e., body image). In this retrospective study, we investigated the relationship between the perceived body image and body composition in women with anorexia nervosa. Specifically, we aimed to verify what components (i.e., weight, body composition, and micronutrients) may predict a higher number of symptoms of negative body image in this clinical condition.

METHODS

Weight status and body composition, including the expressions of vitamins, and body image concerns were measured in a sample of 112 women with anorexia nervosa (age in years M = 26.78; SD = 12; range = 14-67).

RESULTS

According to the regression analysis, a higher skeletal muscle mass and a higher concentration of vitamin B6 seemed to predict a higher number of symptoms of negative body image in our sample.

CONCLUSIONS

This study pointed out muscle mass and the concentration of vitamin B6 as involved in the psychological expression of body image concerns in anorexia nervosa, especially at the beginning of the disease. Thus, we may suggest including and monitoring these parameters in routine care for anorexia nervosa.

Reference Data of Phase Angle Using Bioelectrical Impedance Analysis in Overweight and Obese Chinese

INTRODUCTION

Phase angle (PhA) is a ratio of reactance and resistance {arctangent (reactance (Xc)/resistance (R)) × (180°/π)}, which can be obtained by bioelectrical impedance analysis (BIA). PhA indicates cellular health and integrity, and it is also considered as a prognostic tool in medical disorders and an indicator of nutritional status (especially of muscle quality) in patients with obesity. However, PhA has limited usefulness in clinical practice because of a lackness of reference values for Chinese overweight and obese populations. The main aim of this study was to show PhA reference data in different age and BMI groups by sex. In addition, we also study the association of age, sex, and BMI on PhA.

METHODS

A total of 1729 overweight and obese participants were included in this study. PhA and body composition were measured using segmental multifrequency BIA. Differences in mean values for variables were tested by one-way analysis of variance. Multiple regression analysis was used to assess the associations of PhA with age, sex and BMI.

RESULTS

Multiple regression analysis showed that age, sex and BMI were significant (P < 0.05) independent influence factors of PhA in Chinese overweight and obese adults when age and BMI were continues variables. The mean PhA value for all participants was 5.5°. Mean BMI, age, weight, height and 50kHz-PhA were significantly higher (P < 0.001) in male participants than female ones. In age groups and BMI groups, mean 50kHz-PhA was significantly higher (P < 0.005) in male participants than female ones. When age groups and BMI groups were categorical variables, multiple regression analysis showed that different age groups (46-55 years and ≥ 56 years) had a significantly lower (P < 0.005) PhA as compared with the baseline group (18-25 years) and different BMI groups (≥ 28 kg/m²) had a significantly higher (P < 0.05) PhA as compared with the baseline group (24-27.9 kg/m²).

CONCLUSION

PhA differed according to age, sex and BMI. Reference data in this study can be taken into consideration when deriving the reference values for overweight and obese Chinese populations.

Potential bioelectrical impedance analysis (BIA) parameters in prediction muscle strength in women with anorexia nervosa

OBJECTIVES

The role of physical activity in anorexia nervosa (AN) treatment has been investigated. Muscle strength (MS) reflects physical condition and can predict AN patients' response to this novel treatment approach. This study was intended to find bioelectrical impedance analysis (BIA) parameters that predict AN patients' MS.

METHODS

The study included 42 AN patients and 42 healthy ones in the control group. BIA parameters that predict MS were assessed by dividing AN patients into groups by their hand grip strength test score (higher/lower than 22.5 kg).

RESULTS

The highest accuracy for distinguishing AN subjects from the control group was achieved by cell membrane capacitance (AUC = 0.916), impedance at 200 kHz and 5 kHz ratio (AUC = 0.924), phase angle (PA) 5 kHz (AUC = 0.906) and PA 50 kHz (AUC = 0.919). The low MS group had significantly lower values of PA 50 kHz (mean: 4.03 ± 0.80° vs. 4.58 ± 0.65°; p = 0.032) and fat-free mass index (mean: 12.22 ± 1.41 kg/m² vs. 13.14 ± 0.94 kg/m²; p = 0.026). In the univariate model, PA 50 kHz ≥4.037° was associated with the lowest chance of muscle weakness (OR = 0.230; p = 0.005). In the multivariate analysis, PA 50 kHz was the only significant factor of MS (OR = 0.01; p = 0.027).

CONCLUSIONS

PA 50 kHz is the best BIA parameter to predict MS in AN patients. It could be useful for assessment before physical activity treatment application.

Validity of Bioimpedance Equations to Evaluate Fat-Free Mass and Muscle Mass in Severely Malnourished Anorectic Patients

BACKGROUND

Bioelectrical impedance analysis (BIA) is a simple and rapid technique to measure body composition (BC). Validity of BIA in patients with low body mass index (BMI) remains controversial. We assessed the validity of several BIA equations to evaluate fat-free mass (FFM), fat mass (FM) and muscle mass in patients with anorexia nervosa (AN) by using dual X ray absorptiometry (DXA) as reference.

METHODS

Sixteen BIA equations developed for FFM and appendicular lean mass (ALM) were applied on electrical data measured by BIA in AN patients with BMI <16 kg/m². BIA and DXA were done the same day after overnight fasting. Results were compared with the Bland-Altman method, Pearson correlation and a Lin concordance test.

RESULTS

Data from 115 female AN patients (14.6 ± 1.2 kg/m^²; 32.3 ± 14.5 years) were included. FM and FFM assessed by DXA were, respectively, 4.2 ± 2.4 kg and 35.5 ± 3.8 kg. The best results were obtained with Sun's equation: respectively for FM and FFM, Bland Altman bias at 0.548 and 0.706 kg, Pearson correlation r at 0.86 and 0.86 and Lin concordance coefficient at 0.81 and 0.84. However, confidence intervals (CI) at 95% were high (-2.73-3.83 kg for FM; -4.55-3.13 kg for FFM). Other equations also showed high 95% CI. Accuracy was acceptable for Sun and Bedogni equations for FFM (approximately 66%) but very low for FM prediction considering all equations (<15%). Concerning ALM evaluated at 14.88 ± 2.04 kg by DXA, only Scafoglieri and Yoshida equations showed acceptable values: bias (-0.2 and 2.8%), Pearson r (0.89 and 0.86), Lin concordance coefficient (0.82 and 0.82) and accuracy (83.5 and 82.6%). Confidence intervals at 95% were high for both equations (-2.1-2.0 for Scafoglieri equation and -1.6-2.4 for Yoshida equation).

CONCLUSION

In AN patients with BMI < 16 kg/m², no BIA equation tested was adapted to evaluate BC at the individual level.

The Predictive Role of Raw Bioelectrical Impedance Variables in Disordered Eating Attitudes in Female Ballet Dance Students

The present study used receiver operating characteristic (ROC) curve analysis to investigate the accuracy of body composition and raw bioelectrical impedance analysis (BIA) in correctly classifying disordered eating attitudes (DEA) in dance students. Participants were 81 female dancers assigned in two groups: beginner training (BT; age (mean ± SD) = 10.09 ± 1.2 years, n = 32) and advanced training (AT; age = 15.37 ± 2.1 years, n = 49). Fat mass (FM) was estimated by Slaughter's equation and skeletal muscle with Poortman's equation. Impedance (Z), resistance (R), reactance (Xc) and phase angle (PhA) were obtained through multifrequency BIA at a frequency of 50 kHz. Fat-free mass (FFM) was assessed using Sun's equation. For evaluation of DEA, the Eating Attitudes Test-26 (EAT-26) questionnaire was performed. We defined an EAT-26 score ≥ 20 as positive for DEA. Comparisons between groups were performed by a one-way ANOVA test or Kruskall-Wallis test. Spearman's rank correlation coefficients were performed to assess associations between variables. ROC curve analysis was utilized to test the accuracy of body composition and BIA variables in predicting DEA. In the BT group, Xc and PhA demonstrated high accuracy in predicting DEA with an area under the curve (AUC) of 0.976 (95% confidence interval (CI): 0.85-1.00) and 0.957 (95% CI: 0.82-0.99), respectively, (both p < 0.0001). FFM Sun had an AUC of 0.836 (95% CI: 0.66-0.94) (p < 0.0001) in the BT group and FFM Slaughter was 0.797 (95% CI: 0.66-0.90) (p < 0.001) in the AT group. Reactance and Phase angle were excellent and useful predictors of DEA in the BT group.

Body composition in anorexia nervosa: Meta-analysis and meta-regression of cross-sectional and longitudinal studies

OBJECTIVE

Clinically, anorexia nervosa (AN) presents with altered body composition. We quantified these alterations and evaluated their relationships with metabolites and hormones in patients with AN longitudinally.

METHOD

In accordance with PRISMA guidelines, we conducted 94 meta-analyses on 62 samples published during 1996-2019, comparing up to 2,319 pretreatment, posttreatment, and weight-recovered female patients with AN with up to 1,879 controls. Primary outcomes were fat mass, fat-free mass, body fat percentage, and their regional distribution. Secondary outcomes were bone mineral density, metabolites, and hormones. Meta-regressions examined relationships among those measures and moderators.

RESULTS

Pretreatment female patients with AN evidenced 50% lower fat mass (mean difference [MD]: -8.80 kg, 95% CI: -9.81, -7.79, Q = 1.01 × 10-63 ) and 4.98 kg (95% CI: -5.85, -4.12, Q = 1.99 × 10-28 ) lower fat-free mass, with fat mass preferentially stored in the trunk region during early weight restoration (4.2%, 95% CI: -2.1, -6.2, Q = 2.30 × 10-4 ). While the majority of traits returned to levels seen in healthy controls after weight restoration, fat-free mass (MD: -1.27 kg, 95% CI: -1.79, -0.75, Q = 5.49 × 10-6 ) and bone mineral density (MD: -0.10 kg, 95% CI: -0.18, -0.03, Q = 0.01) remained significantly altered.

DISCUSSION

Body composition is markedly altered in AN, warranting research into these phenotypes as clinical risk or relapse predictors. Notably, the long-term altered levels of fat-free mass and bone mineral density suggest that these parameters should be investigated as potential AN trait markers.

RESUMENOBJETIVO

Clínicamente, la anorexia nervosa (AN) se presenta con alteraciones en la composición corporal. Cuantificamos estas alteraciones y evaluamos longitudinalmente su relación con metabolitos y hormonas en pacientes con AN. MÉTODO: De acuerdo con las pautas PRISMA, realizamos 94 meta-análisis en 62 muestras publicadas entre 1996-2019, comparando hasta 2,319 pacientes mujeres en pre-tratamiento, post-tratamiento, y recuperadas en base al peso con hasta 1,879 controles. Las principales medidas fueron masa grasa, masa libre de grasa, porcentaje de grasa corporal y su distribución regional. Las medidas secundarias fueron densidad mineral ósea, metabolitos y hormonas. Las meta-regresiones examinaron las relaciones entre esas medidas y moderadores.

RESULTADOS

Las pacientes femeninas con AN pre-tratamiento mostraron un 50% menos de masa grasa (MD: -8.80 kg, CI 95%: -9.81, -7.79, Q = 1.01 × 10-63 ) y 4.98 kg (CI 95%: -5.85, -4.12, Q = 1.99 × 10-28 ) menos de masa libre de grasa, con masa grasa preferentemente almacenada en la región del tronco durante la recuperación temprana del peso (4.2%, CI 95%: -2.1, -6.2, Q = 2.30 × 10-4 ). Aunque la mayoría de los rasgos regresaron a los niveles vistos en los controles sanos después de la restauración del peso, la masa libre de grasa (MD: -1.27 kg, CI 95%: -1.79, -0.75, Q = 5.49 × 10-6 ) y la densidad mineral ósea (MD: -0.10 kg, CI 95%: -0.18, -0.03, Q = 0.01) permanecieron significativamente alteradas. DISCUSIÓN: La composición corporal es marcadamente alterada en la AN, lo que garantiza la investigación en estos fenotipos como predictores de riesgo clínico o de recaída. Notablemente, la alteración a largo plazo de los niveles de masa libre de grasa y densidad mineral ósea sugieren que estos parámetros debe ser investigados como potenciales rasgos indicadores de AN.

Anthropometrical and Bioelectrical Impedance Analysis Parameters in Anorexia Nervosa Patients' Nutritional Status Assessment

Background and Objectives: Body mass index (BMI) is still the only recommended measurable nutritional status assessment parameter in anorexia nervosa (AN). The aim of this study was to measure other anthropometrical and bioelectrical impedance analysis (BIA) parameters in AN patients and to evaluate their nutritional status assessment value. Materials and Methods: The 46 AN female patients were examined at the beginning of hospitalization and followed-up in three measurements (in 6 ± 2 weeks’ intervals). Anthropometrical assessment was based on BMI, circumferences of arm, calf, thigh, hips, waist, their ratio (waist-to-hip ratio (WHR)), and a skinfold test over biceps and triceps muscle, under the scapula, over the hip, and 2 cm from the umbilicus. The BIA parameters included phase angle (PA), membrane capacitance (Cm), and impedance at 200 kHz, and a 5 kHz ratio (Z_200/5). Results: In the 1st measurement, BMI correlated with all anthropometric and BIA parameters (p < 0.05). For BIA parameters, the correlation included arm circumference and WHR (p < 0.05). In the follow-up, significant changes were observed in BMI and all BIA parameters. The correlation between BMI and all BIA parameters was present in the 2nd and 3rd measurements (p < 0.05). In the 4th measurement, BMI correlated only with Cm (p = 0.0114). Comparison of BIA parameters according to the state of starvation (BMI < 16.0 kg/m²) revealed that all studied BIA parameters were characterized by statistically significant sensitivity and specificity in the detection of this condition (p < 0.05), except PA in the 4th measurement (p = 0.2099). Conclusions: Selected BIA and anthropometrical parameters could be used for AN patients’ assessment. The study confirmed dynamic changes of BIA parameters during the follow-up. They could be useful in the detection of the state of starvation.

Assessment of Body Composition in Health and Disease Using Bioelectrical Impedance Analysis (BIA) and Dual Energy X-Ray Absorptiometry (DXA): A Critical Overview

The measurement of body composition (BC) represents a valuable tool to assess nutritional status in health and disease. The most used methods to evaluate BC in the clinical practice are based on bicompartment models and measure, directly or indirectly, fat mass (FM) and fat-free mass (FFM). Bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DXA) (nowadays considered as the reference technique in clinical practice) are extensively used in epidemiological (mainly BIA) and clinical (mainly DXA) settings to evaluate BC. DXA is primarily used for the measurements of bone mineral content (BMC) and density to assess bone health and diagnose osteoporosis in defined anatomical regions (femur and spine). However, total body DXA scans are used to derive a three-compartment BC model, including BMC, FM, and FFM. Both these methods feature some limitations: the accuracy of BIA measurements is reduced when specific predictive equations and standardized measurement protocols are not utilized whereas the limitations of DXA are the safety of repeated measurements (no more than two body scans per year are currently advised), cost, and technical expertise. This review aims to provide useful insights mostly into the use of BC methods in prevention and clinical practice (ambulatory or bedridden patients). We believe that it will stimulate a discussion on the topic and reinvigorate the crucial role of BC evaluation in diagnostic and clinical investigation protocols.

Comparison of body composition assessment by DXA and BIA according to the body mass index: A retrospective study on 3655 measures

BACKGROUND AND AIMS

Body composition assessment is often used in clinical practice for nutritional evaluation and monitoring. The standard method, dual-energy X-ray absorptiometry (DXA), is hardly feasible in routine clinical practice contrary to Bioelectrical Impedance Analysis (BIA) method. We thus aimed to compare body composition assessment by DXA and BIA according to the body mass index (BMI) in a large cohort.

METHODS

Retrospectively, we analysed DXA and BIA measures in patients followed in a Nutrition Unit from 2010 to 2016. Body composition was assessed under standardized conditions in the morning, after a fasting period of 12 h, by DXA (Lunar Prodigy Advance) and BIA (Bodystat QuadScan 4000, Manufacturer's equation). Bland-Altman test was performed for each class of BMI (kg/m2) and fat mass and fat free mass values were compared using Kruskal-Wallis test. Pearson correlations were also performed and the concordance coefficient of Lin was calculated.

RESULTS

Whatever the BMI, BIA and DXA methods reported higher concordance for values of FM than FFM. Body composition values were very closed for patients with BMI between 16 and 18,5 (difference < 1kg). For BMI > 18,5 and BMI < 40, BIA overestimated fat free mass from 3,38 to 8,28 kg, and underestimated fat mass from 2,51 to 5,67 kg compared with DXA method. For BMI ≥ 40, differences vary with BMI. For BMI < 16, BIA underestimated fat free mass by 2,25 kg, and overestimated fat mass by 2,57 kg. However, limits of agreement were very large either for FM and FFM values, irrespective of BMI.

CONCLUSION

The small bias, particularly in patients with BMI between 16 and 18, suggests that BIA and DXA methods are interchangeable at a population level. However, concordance between BIA and DXA methods at the individual level is lacking, irrespective of BMI.

Prediction of body composition in anorexia nervosa: Results from a retrospective study

BACKGROUND & AIMS

The assessment of body composition is crucial in evaluating nutritional status in female subjects with anorexia nervosa (AN) and improving their clinical management. The aim of this retrospective study was to assess the accuracy of selected BIA (bioimpedance analysis) equations for fat-free mass (FFM) in female AN subjects and to formulate a specific equation for these subjects.

METHODS

Eighty-two restrictive female AN subjects (age 20.5 ± 3.7 yrs, BMI 15.7 ± 1.7 kg/m²) were studied. Body composition was determined with dual-energy X-ray absorptiometry (DXA) and estimated by BIA using five different equations. Linear correlation analysis was carried out to evaluate the association of FFM with selected variables. Multiple regression analysis was used to formulate specific equations to predict FFM in AN.

RESULTS

All predictive equations underestimated FFM at the population level with a bias from -5.6 to -11.7%, while the percentage of accurate predictions varied from 12.2% to 35.4%. More interestingly, multiple regression analysis clearly indicates that, in addition to weight, ZI₁₀₀ or RI also emerged as independent predictors of DXA-derived FFM, increasing the prediction power of the equation well above that observed with anthropometric characteristics only.

CONCLUSIONS

This study shows that the selected predictive BIA equations considered exhibit an insufficient accuracy at the population and the individual level. Predictive formulas based on body weight plus BIA parameters such as RI and ZI₁₀₀ offer a rather accurate prediction of FFM (with high R squared).

Body Mass Index and Agreement Between Bioimpedance and Anthropometry Estimates of Body Compartments in Anorexia Nervosa

BACKGROUND

In 74 women with anorexia nervosa (body mass index [BMI] 10-17.5 kg/m(2)), a progressive disagreement between anthropometry and bioelectrical impedance analysis (BIA) estimates of fat (FM) and fat-free mass (FFM) was documented with a BMI <15 kg/m(2). Below this threshold, an abnormal body composition was detected with vector BIA independent on body weight (useful tool at the bedside). Both anthropometry and BIA are used for body composition assessment. We evaluated the agreement between their estimates of FFM and FM in extremely lean subjects with anorexia nervosa.

METHODS

Observational study in 74 women (age 15-45 years; BMI 10.0-17.5 kg/m(2)) with anorexia nervosa. Anthropometry FM and FFM were estimated by skinfold thicknesses. Whole-body impedance vector components, resistance (R) and reactance (X(c)), were measured at the same time (BIA-101 analyzer, 50-kHz frequency; Akern/RJL Systems, Clinton Twp., MI). BIA estimates of FFM and FM were obtained with Sun's equations (BMI 14-39 kg/m(2)). Vector BIA was performed with the RXc graph method. The frequency of disagreement between anthropometry and BIA was evaluated as a function of increasing BMI (receiver operating characteristic curve).

RESULTS

The correlation coefficient between methods was 0.80-0.90. The BMI cutoff value of 15 kg/m(2) predicted disagreement of FM and FFM in patients with a BMI <15 kg/m(2). In the RXc graph, the distribution of vectors from patients with disagreement was significantly shifted out of the right border of the reference tolerance ellipses.

CONCLUSIONS

Anthropometry and BIA equations should not be used in anorexic patients with a BMI <15 kg/m(2). The distribution of vectors from patients with disagreement of methods was shifted out of the right border of the reference tolerance ellipses and was superposed to vectors from patients with a BMI <15 kg/m(2). The identified impedance pattern for anorexia could be useful for feedback in individual patient refeeding (vector back into the 75% reference ellipse).

Anthropometric Predictors of Bio-Impedance Analysis (BIA) Phase Angle in Healthy Adults

INTRODUCTION

Phase Angle (PhA) is a ratio of whole body reactance and resistance obtained from Bioelectrical Impedance Analysis (BIA). It indicates cellular health and integrity and is considered as prognostic tool in medical disorders. In spite of prognostic potentials of PhA, it has limited usefulness in clinical practice and in population studies because of non-availability of normal population reference limits for comparison. Moreover, it is influenced by various factors like age, sex, race and body composition (i.e. body fat, muscle mass, visceral fat, body cell mass, total body water, etc).

AIM

The aim of this study was to evaluate predictors of phase angle which will be useful in formulation of reference values for Indian population.

MATERIALS AND METHODS

BIA was performed by Tanita Body Composition Analyser on healthy adults aged 17-24 years. The inbuilt software measured the phase angle by the formula: Phase angle (PhA) = Reactance (xc)/Resistance (R)* (180/π). Phase angle values were compared across categories of age, sex, weight, height, Body Mass Index (BMI), total fat, visceral fat and muscle mass.

RESULTS

Mean value of phase angle was found to be 5.65. Phase angle was significantly (p< 0.001) higher in male than in female. Phase angle was significantly predicted from height (p< 0.001), weight (p< 0.002), muscle mass (p< 0.002) and visceral fat (p< 0.02) in multiple regression models.

CONCLUSION

Phase angle differs across anthropometric and body composition categories. Thus height, weight and muscle mass should also be taken into consideration while deriving population specific reference limits of phase angle.

Bioelectrical impedance vector analysis (BIVA) for the assessment of two-compartment body composition

This review is directed to define the efficacy of bioelectrical impedance vector analysis (BIVA) for assessing two-compartment body composition. A systematic literature review using MEDLINE database up to 12 February 2014 was performed. The list of papers citing the first description of BIVA, obtained from SCOPUS, and the reference lists of included studies were also searched. Selection criteria included studies comparing the results of BIVA with those of other techniques, and studies analyzing bioelectrical vectors of obese, athletic, cachectic and lean individuals. Thirty articles met the inclusion criteria. The ability of classic BIVA for assessing two-compartment body composition has been mainly evaluated by means of indirect techniques, such as anthropometry and bioelectrical impedance analysis (BIA). Classic BIVA showed a high agreement with body mass index, that can be interpreted in relation to the greater body mass of obese and athletic individuals, whereas the comparison with BIA showed less consistent results, especially in diseased individuals. When a reference method was used, classic BIVA failed to accurately recognize FM% variations, whereas specific BIVA furnished good results. Specific BIVA is a promising alternative to classic BIVA for assessing two-compartment body composition, with potential application in nutritional, sport and geriatric medicine.

Association between phase angle, anthropometric measurements, and lipid profile in HCV-infected patients

OBJECTIVE

The objective of this study was to investigate the associations between phase angle, anthropometric measurements, and lipid profile in patients chronically infected with the hepatitis C virus.

METHODS

A total of 160 consecutive patients chronically infected with the hepatitis C virus and who received treatment at the hepatitis C outpatient unit of our hospital from April 2010 to May 2011 were prospectively evaluated. Bioelectrical impedance analysis, anthropometric measurements, and serum lipid profile analysis were performed.

RESULTS

Twenty-five patients were excluded. A total of 135 patients with a mean age of 49.8±11.4 years were studied. Among these patients, 60% were male. The phase angle and BMI means were 6.5±0.8° and 26.5±4.8 kg/m2, respectively. Regarding anthropometric variables, mid-arm circumference, mid-arm muscle circumference, and arm muscle area had a positive correlation with phase angle. In contrast, when analyzing the lipid profile, only HDL was inversely correlated with phase angle. However, in multiple regression models adjusted for age and gender, only mid-arm circumference (p = 0.005), mid-arm muscle circumference (p = 0.003), and arm muscle circumference (p = 0.001) were associated with phase angle in hepatitis C virus-infected patients.

CONCLUSIONS

In conclusion, phase angle is positively correlated with anthropometric measures in our study. However, there is no association between phase angle and lipid profile in these patients. Our results suggest that phase angle is related to lean body mass in patients chronically infected with hepatitis C virus.

Higher calorie diets increase rate of weight gain and shorten hospital stay in hospitalized adolescents with anorexia nervosa

PURPOSE

Current recommendations for refeeding in anorexia nervosa (AN) are conservative, beginning around 1,200 calories to avoid refeeding syndrome. We previously showed poor weight gain and long hospital stay using this approach and hypothesized that a higher calorie approach would improve outcomes.

METHODS

Adolescents hospitalized for malnutrition due to AN were included in this quasi-experimental study comparing lower and higher calories during refeeding. Participants enrolled between 2002 and 2012; higher calories were prescribed starting around 2008. Daily prospective measures included weight, heart rate, temperature, hydration markers and serum phosphorus. Participants received formula only to replace refused food. Percent Median Body Mass Index (%MBMI) was calculated using 50th percentile body mass index for age and sex. Unpaired t-tests compared two groups split at 1,200 calories.

RESULTS

Fifty-six adolescents with mean (±SEM) age 16.2 (±.3) years and admit %MBMI 79.2% (±1.5%) were hospitalized for 14.9 (±.9) days. The only significant difference between groups (N = 28 each) at baseline was starting calories (1,764 [±60] vs. 1,093 [±28], p < .001). Participants on higher calories had faster weight gain (.46 [±.04] vs. .26 [±.03] %MBMI/day, p < .001), greater daily calorie advances (122 [±8] vs. 98 [±6], p = .024), shorter hospital stay (11.9 [±1.0] vs. 17.6 [±1.2] days, p < .001), and a greater tendency to receive phosphate supplementation (12 vs. 8 participants, p = .273).

CONCLUSIONS

Higher calorie diets produced faster weight gain in hospitalized adolescents with AN as compared with the currently recommended lower calorie diets. No cases of the refeeding syndrome were seen using phosphate supplementation. These findings lend further support to the move toward more aggressive refeeding in AN.

Low phase angle determined by bioelectrical impedance analysis is associated with malnutrition and nutritional risk at hospital admission

BACKGROUND & AIMS

This study determined the association between phase angle (PhA), by bioelectrical impedance analysis (BIA) and nutritional risk by Nutritional Risk Screening (NRS-2002), Subjective Global Assessment (SGA), hospital length of stay (LOS) and 30 day non-survival in patients at hospital admission compared to healthy controls.

METHODS

PhA was determined by BIA in patients (n = 983, 52.7 ± 21.5 yrs, M 520) and compared to healthy age-, sex- and height-matched controls. Low PhA was set at <5.0° (men) and <4.6° (women) as previously determined (Kyle, in press).

RESULTS

PhA was lower in patients (men 6.0 ± 1.4°, women 5.0 ± 1.3°) than controls (men 7.1 ± 1.2°, women 6.0 ± 1.2°, un-paired t-test p < 0.001). Patients were more likely to have low PhA than controls: NRS-2002: no risk (relative risk (RR) 1.7, 95th confidence interval (CI) 1.2-2.3), moderate risk (RR 4.5, CI 3.4-5.8) and severe risk (RR 7.5, CI 5.9-9.4); similar results were obtained by SGA; LOS ≥21 days (RR 6.9, CI 5.1-9.1) and LOS 5-20 days (RR 5.2, CI 3.9-6.9) and non-survivors (RR 3.1, CI 2.1-3.4) compared to survivors.

CONCLUSIONS

There is a significant association between low PhA and nutritional risk, LOS and non-survival. PhA is helpful to identify patients who are at nutritional risk at hospital admission in order to limit the number of in-depth nutritional assessments.

Bioelectrical phase angle and impedance vector analysis--clinical relevance and applicability of impedance parameters

BACKGROUND & AIMS

The use of phase angle (PhA) and raw parameters of bioelectrical impedance analysis (BIA) has gained attention as alternative to conventional error-prone calculation of body composition in disease. This review investigates the clinical relevance and applicability of PhA and Bioelectrical Impedance Vector Analysis (BIVA) which uses the plot of resistance and reactance normalized per height.

METHODS

A comprehensive literature search was conducted using Medline identifying studies relevant to this review until March 2011. We included studies on the use of PhA or BIVA derived from tetrapolar BIA in out- and in-patient settings or institutionalized elderly.

RESULTS

Numerous studies have proven the prognostic impact of PhA regarding mortality or postoperative complications in different clinical settings. BIVA has been shown to provide information about hydration and body cell mass and therefore allows assessment of patients in whom calculation of body composition fails due to altered hydration. Reference values exist for PhA and BIVA facilitating interpretation of data.

CONCLUSION

PhA, a superior prognostic marker, should be considered as a screening tool for the identification of risk patients with impaired nutritional and functional status, BIVA is recommended for further nutritional assessment and monitoring, in particular when calculation of body composition is not feasible.

A prospective examination of weight gain in hospitalized adolescents with anorexia nervosa on a recommended refeeding protocol

PURPOSE

Current refeeding recommendations for adolescents hospitalized with anorexia nervosa (AN) are conservative, starting with low calories and advancing slowly to avoid refeeding syndrome. The purpose of this study was to examine weight change and clinical outcomes in hospitalized adolescents with AN on a recommended refeeding protocol.

METHODS

Adolescents aged 13.1-20.5 years were followed during hospitalization for AN. Weight, vital signs, electrolytes, and 24-hour fluid balance were measured daily. Percent median body mass index (%MBMI) was calculated as 50th percentile BMI for age and gender. Calories were prescribed on admission and were increased every other day.

RESULTS

Thirty-five subjects with a mean (SD) age of 16.2 (1.9) years participated over 16.7 (6.4) days. Calories increased from 1,205 (289) to 2,668 (387). No subjects had refeeding syndrome; 20% had low serum phosphorus. Percent MBMI increased from 80.1 (11.5) to 84.5 (9.6); overall gain was 2.10 (1.98) kg. However, 83% of subjects initially lost weight. Mean %MBMI did not increase significantly until day 8. Higher calories prescribed at baseline were significantly associated with faster weight gain (p = .003) and shorter hospital stay (p = .030) in multivariate regression models adjusted for %MBMI and lowest heart rate on admission.

CONCLUSIONS

Hospitalized adolescents with AN demonstrated initial weight loss and slow weight gain on a recommended refeeding protocol. Higher calorie diets instituted at admission predicted faster weight gain and shorter hospital stay. These findings support the development of more aggressive feeding strategies in adolescents hospitalized with AN. Further research is needed to identify caloric and supplementation regimens to maximize weight gain safely while avoiding refeeding syndrome.

Underweight patients with anorexia nervosa: comparison of bioelectrical impedance analysis using five equations to dual X-ray absorptiometry

BACKGROUND & AIMS

Body weight changes do not reflect the respective changes of body compartments, namely fat-free mass (FFM) and fat mass (FM). Both bioelectrical Impedance Analysis (BIA) and the Dual X-ray absorptiometry (DXA) measure FFM and FM. This study in underweight patients with anorexia nervosa (AN) aims to compare measurements of FM and FFM done by DXA and BIA using 5 different BIA equations already validated in healthy population and to identify the most suitable BIA equation for AN patients.

METHODS

Fifty female patients with AN (BMI=14.3 ± 1.49, age=19.98 ± 5.68yrs) were included in the study. Body composition was measured by DXA (Delphi W, Hologic, Bedford, MA) and by 50 kHz BIA (FORANA, Helios) using 5 different BIA equations validated in healthy population (Sun, Geneva, Kushner, Deurenberg and Roubenoff equations). Comparison between the DXA and the 5 BIA equations was done using the sum of the squares of differences and Bland-Altman plots.

RESULTS

The Deurenberg equation gave the best estimates of FFM when compared to the measurements by DXA (FFM(dxa)=35.80 kg versus FFM(deurenberg)=36.36 kg) and very close estimates of FM (FM(dxa)=9.16 kg and FM(deurenberg)=9.57 kg) The Kushner equation showed slightly better estimates for FM (FM(kushner)=9. 0kg) when compared to the DXA, but not for FFM. Sun equation gave the broadest differences for FM and FFM when compared with DXA.

CONCLUSION

The best available BIA equation to calculate the FFM and the FM in patients with AN is the Deurenberg equation. It takes into account the weight, height and age and is applicable in adults and adolescents AN patients with BMI of 12.8-21.0, and for ages between 13.4 and up to 36.9 years.

Patients with eating disorders and their siblings. An investigation of body image perceptions

Little is known about body images of siblings of patients with eating disorders. In this study we investigated body images of patients with anorexia or bulimia nervosa and of the patients' brothers and sisters. A computer program was employed that allows modeling perceived and desired body images of patients and family members. Patients, siblings and male and female control subjects rated their body images. The selected images were compared with anthropometric data. All subjects also filled out a body image questionnaire. Data from 30 patients, 38 siblings, and 60 control subjects are presented. Siblings did not differ from healthy control subjects. Self-ideal discrepancy was different in patients with anorexia and their sisters. Body image was more negative in patients than in their sisters. Siblings of patients with eating disorders seem to be rather unimpaired in terms of body image disturbances.

Perceptual body image of patients with anorexia or bulimia nervosa and their fathers

PURPOSE

Little is known about how fathers of patients with eating disorders perceive their own body. In this study we investigated body image perception of patients with anorexia and bulimia nervosa and body image perception of their fathers in a computer assisted approach.

METHODS

A computer program, the somatomorphic matrix, is presented that allows modeling of perceived and desired body-images of patients and their relatives. Patients and fathers rated their own body images and fathers additionally rated the body images of their daughters. The images implemented in the program correspond with defined percentages of body fat and muscularity. Selected images were compared with subjects' anthropometric data regarding body fat and muscularity. Data from 42 father-daughter-dyads (27 patients with anorexia, 15 with bulimia nervosa) were examined. Differences between both diagnostic groups were compared and associations between fathers' and daughters' body image perceptions within each group were investigated.

RESULTS

Patients with anorexia nervosa overestimated their bodies on the body fat dimension. Patients with bulimia nervosa wished to have a body with less fat. Fathers of both groups of patients perceived their own bodies correctly but wished to have less body fat and to be more muscular. The wish for a change in body fat of anorexia nervosa patients was highly correlated with fathers' BMI (r=0.49; p=0.009). The wish for a change in body fat of bulimia nervosa patients was correlated with fathers' distorted body image perception in terms of muscularity (r=-0.66, p=0.007) and with fathers' wish for a more muscular body (r=-0.51, p=0.05).

CONCLUSION

Body images of patients with eating disorders and their fathers are related in the group of patients with bulimia nervosa. Perhaps, body images of fathers should be addressed in family therapy with patients with bulimia nervosa.

Body image in patients with eating disorders and their mothers, and the role of family functioning

OBJECTIVE

Little is known about body images of mothers of patients with eating disorders. In this study we investigated body image in patients with eating disorders and in their mothers, and the relationship of their body images with family functioning.

METHODS

A computer program was used that allows modeling perceived and desired body images of patients and their mothers. Patients and mothers estimated their own body images and mothers estimated the images they have of their daughters with eating disorders. The selected images were compared to anthropometric data and family functioning according to the Family Assessment Measure. Data from 29 patients with the diagnosis of anorexia nervosa and 20 patients with bulimia nervosa are presented.

RESULTS

Both in patients with anorexia and in patients with bulimia, aspects of family functioning were associated with mothers' and daughters' perceptual body size distortion and body dissatisfaction. Mothers' perception of family functioning predicted daughters' perceptual body size distortion and body dissatisfaction in the total sample of 49 patients.

CONCLUSION

Body images of mothers and mothers' perceptions of family functioning may provide additional information for the treatment of patients with eating disorders.

Body images of patients with anorexia nervosa, bulimia nervosa and female control subjects: a comparison with male ideals of female attractiveness

Body images of female patients with anorexia nervosa and bulimia nervosa were assessed against females without eating disorders and compared with male ideals of female attractiveness. A computer program was applied to examine body images of 62 patients with anorexia nervosa, 45 patients with bulimia nervosa, and 40 female and 39 male control subjects. Body size overestimation was most distinct in the two patient groups. Self-ideal discrepancy was highest in bulimia nervosa. Estimation of the society's ideal female body in all three female groups did not differ from men's perception of the most attractive female body. Congruence of ideals of female attractiveness in patients, female, and male control subjects and described differences between patients and female controls support the theory that body image disturbance is a problem of processing self-referential information regarding body image rather than a problem of processing body image related information per se.

Energy expenditure adjusted for body composition differentiates constitutional thinness from both normal subjects and anorexia nervosa

Constitutional thinness (CT) is characterized by a low and stable body mass index (BMI) without any hormonal abnormality. To understand the weight steadiness, energetic metabolism was evaluated. Seven CT, seven controls, and six anorexia nervosa (AN) young women were compared. CT and AN had a BMI <16.5 kg/m(2). Four criteria were evaluated: 1) energy balance including diet record, resting metabolic rate (RMR) (indirect calorimetry), total energy expenditure (TEE) (doubly labeled water), physical activity; 2) body composition (dual-energy X-ray absorptiometry); 3) biological markers (leptin, IGF-I, free T3); 4) psychological profile of eating behavior. The normality of free T3 (3.7 +/- 0.5 pmol/l), IGF-I (225 +/- 93 ng/ml), and leptin (8.3 +/- 3.4 ng/ml) confirmed the absence of undernutrition in CT. Their psychological profiles revealed a weight gain desire. TEE (kJ/day) in CT (8,382 +/- 988) was not found significantly different from that of controls (8,793 +/- 845) and AN (8,001 +/- 2,152). CT food intake (7,565 +/- 908 kJ/day) was found similar to that of controls (7,961 +/- 1,452 kJ/day) and higher than in AN (4,894 +/- 703 kJ/day), thus explaining the energy metabolism balance. Fat-free mass (FFM) (kg) was similar in CT and AN (32.5 +/- 2.9 vs. 34.1 +/- 1.9) and higher in controls (37.8 +/- 1.6). While RMR absolute values (kJ/day) were lower in CT (4,839 +/- 473) than in controls (5,576 +/- 209), RMR values adjusted for FFM were the highest in CT. TEE-to-FFM ratio was also higher in CT than in controls. Energetic metabolism balance maintains a stable low weight in CT. An increased energy expenditure-to-FFM ratio differentiates CT from controls and could account for the resistance to weight gain observed in CT.

Phase angle is a predictor of basal metabolic rate in female patients with anorexia nervosa

The aim of the study was to evaluate the relationship between basal metabolic rate (BMR) and bioelectrical impedance analysis (BIA) in undernourished female patients with anorexia nervosa. Participants were 86 female patients with anorexia nervosa (age 20.8+/-4.7 years; weight 39.3+/-5.2 kg; body mass index 15.4+/-1.6 kg m-2). BMR was measured by indirect calorimetry and single-frequency BIA was determined at 50 kHz on the whole body. The BIA variables considered were resistance, reactance, phase angle and the bioimpedance index (height2/resistance). Fat-free mass was calculated from subcutaneous skin fold thickness. In the study group BMR was 3782+/-661 kJ d-1 while bioimpedance index varied between 27.6 and 49.9 cm2 Omega-1 and phase angle between 2.54 degrees and 6.49 degrees. BMR was significantly correlated with weight, height, body mass index and fat-free mass, and, among BIA variables, with reactance and phase angle. Multiple regression analysis indicated that phase angle was a predictor of BMR not only when solely BIA variables were considered, but also in combination with either weight and age or fat-free mass. In conclusion, phase angle emerged as a strong predictor of BMR in female patients with anorexia nervosa. Nevertheless, further studies are necessary to confirm this finding in other forms of protein energy malnutrition and justify the inclusion of BIA variables in the equations used to predict BMR in the clinical setting.

Improvement of nutritional status as assessed by multifrequency BIA during 15 weeks of refeeding in adolescent girls with anorexia nervosa

In patients with anorexia nervosa (AN), an assessment of changes in body composition and nutritional status is crucial for adequate nutritional management during refeeding therapies. Phase-sensitive multifrequency bioelectrical impedance analysis (BIA) is an inexpensive and noninvasive technique with which to determine nutritional status and body composition. We investigated 21 female adolescents with AN (initial BMI 15.5 +/- 1.1 kg/m(2)) 4 times between wk 3 and 15 of inpatient refeeding and 19 normal-weight, age-matched female controls. From wk 3 to 15, BMI, fat mass, body cell mass (BCM), total body water (TBW), intracellular water (ICW) but not extracellular mass (ECM), and extracellular water (ECW) increased significantly. Reactance (Xc), phase angle (PhA), and the ECM/BCM index as parameters of nutritional status improved significantly in patients and no longer differed from controls in wk 15, although the BMI of patients was significantly lower than those of controls. Changes in the ECM/BCM index were due to accretion of BCM, which was associated with an increase of ICW. Multifrequency phase-sensitive BIA seems to be a promising tool for the assessment of changes in nutritional status and body composition in patients with AN. An individually determined and controlled hyperenergetic diet as part of a multidimensional, interdisciplinary treatment program for eating disorders seems to quickly improve the nutritional status of AN patients.

Long-Term Nutritional and Digestive Consequences of Pelvic Radiation

OBJECTIVE

To study long-term changes in nutritional status and gastrointestinal (GI) functions of 15 women previously treated with radiotherapy for gynecological cancer. Two years prior to this research, these patients had been assessed twice: before external radiotherapy and 5 weeks later, at the completion of the external dose (45-50 Gy).

METHODS

Each patient was given complete clinical evaluation, consisting of dietary, physical activity and digestive symptoms questionnaires. Blood was drawn for routine clinical laboratory tests (hemoglobin, white blood cell count, creatinine, lipoproteins, glucose, total proteins, albumin, and C reactive protein). Body composition was assessed by classical anthropometric indicators and double beam X-ray absorptiometry (DEXA), while muscle strength was measured through a hand dynamometer. Resting energy expenditure (REE), obtained by indirect calorimetry, was subtracted from energy ingestion, derived from dietary records, to calculate energy balance.

RESULTS

This third evaluation included fifteen patients. A significant increase in body mass index (BMI), % body fat and waist circumference were observed in comparison to earlier evaluations. The lean compartment decreased significantly, and REE descended in parallel. Meanwhile, total energy, fat and protein intake increased, compared to previous measurements. The changes in bowel habits observed during radiotherapy persisted at this third evaluation, with the exception of diarrhea, which was less reported. Abdominal bloating and rectal symptoms were the most prevalent complaints.

CONCLUSIONS

After radiation treatment for gynecological cancer, patients gained more body fat than expected in Chilean women around menopause. In spite of high protein ingestion, the loss of fat-free mass observed during radiation treatment was not recovered along with weight increase. This is probably associated with infrequent physical activity, both during and after treatment, and hyperphagia.

History of anorexia nervosa in bulimic patients: its influence on body composition

OBJECTIVE

To analyze the body composition of a group of patients fulfilling DSM-IV criteria for bulimia nervosa (BN), comparing the patients who had a history of DSM-IV anorexia nervosa (AN) with those without such a history to determine (1) whether both groups differed in terms of body composition and (2) whether the differences between groups could be the consequence of the past condition.

METHODS

The sample consisted of 104 patients, 43 with prior AN (BN-AN group) and 61 without a history of AN (BN-nonAN). The patients were assessed using anthropometric and bioelectrical methods: height and weight, body circumferences, abdominal diameter, skinfold thickness, and body impedance analysis. In a later phase and to test the influence of current low weight on the results, two experimental groups were created: the first group was composed of the patients from the BN-AN group who had a normal body mass index (BMI range in this group, 20.1-23.4 kg/m2; n = 23); the second group consisted of 23 patients from the BN-nonAN group in the same BMI range. In both phases unpaired sample t tests were performed for statistical analysis.

RESULTS

More than 40% of the bulimic patients with a history of AN had a BMI less than 20. They had a lower percentage of body fat, lower muscle mass, and higher percentage of extracellular water. Nevertheless, most of these differences disappeared in the second phase of the analysis, when only the patients within a normal weight range were compared.

DISCUSSION

According to these results, a significant number of bulimic patients with a history of AN tend to retain some clinical traits of the past condition and could be viewed as remaining in a "subclinical anorexic status": they are thinner and seem to have less difficulties in maintaining low weight than patients without a history of AN. Nevertheless, in patients who have reached a normal weight after AN, all these differences disappear. This fact raises some important questions related to the boundaries between AN and BN, the shifting from one to another, or when AN patients really recover.

Body composition changes in patients with anorexia nervosa after complete weight recovery

OBJECTIVE

To assess body composition changes occurring in female anorectic patients after complete weight recovery.

DESIGN

Longitudinal study.

SUBJECTS

: Ten female patients with anorexia nervosa (age at baseline: 19.7+/-5.8 y) were studied both when undernourished (body mass index, BMI 14.8+/-1.3 kg/ m(2)) and after the achievement of a BMI >18.5 kg/m(2). The control group comprised 18 well-nourished women (age 20.1+/-4.4 y; BMI 19.0-23.0 kg/ m(2)).

INTERVENTIONS

Fat mass and fat-free mass were determined by dual-energy X-ray absorptiometry. Skinfold thicknesses and circumferences were also measured. Arm muscle area and arm fat area were calculated by standard formulas.

RESULTS

The undernourished patients had lower fat-free mass, fat mass, skinfold thicknesses and circumferences. After refeeding, fat mass represented 25-71% (mean 56%) of the mass regained, this percentage being directly related to the extent of weight gain. The increases in skinfolds and circumferences depended upon the site considered and were correlated to a various extent with those in weight or BMI. Skinfolds at biceps and abdominal sites and the waist-to-hip ratio remained significantly higher, whereas arm muscle circumference was significantly lower, in the refed group than in the control one.

CONCLUSION

The percentage of fat in the weight regained by refed female anorectic patients was directly related to the extent of body mass increase. Refed anorectic patients appear to preferentially regain fat in the abdominal and triceps regions. Abnormalities in skinfolds (at biceps and abdominal sites), arm muscle area and waist-to-hip ratio still persist in refed anorectic patients in comparison to control healthy controls.