Phase angle as an indicator of body composition and physical performance in handball players.

BACKGROUND: Phase angle (PhA), obtained from the bioimpedance analysis, is widely used in clinical situations and in sports. This study evaluated the association between PhA with body composition and physical performance of handball athletes. METHODS: 43 national-level players (22.19 ± 3.86 years) of both sexes were evaluated regarding anthropometry, body composition, squat (SJ) and countermovement (CMJ) jumps, handgrip strength, and cardiorespiratory fitness. RESULTS: We verified a correlation between PhA of the whole body and fat-free mass (r = 0.511), body mass index (r = 0.307), and body fat % (r = -0.303). There was a positive correlation between PhA of the whole body and SJ (r = 0.376), CMJ (r = 0.419), and handgrip for the dominant hand (r = 0.448). Moreover, PhA of the upper limbs was more strongly correlated with handgrip for the dominant (r = 0.630) and non-dominant hand (r = 0.575) compared to PhA of the whole body considering both sexes. Similarly, segmental PhA had a stronger significant correlation with SJ (r = 0.402) and handgrip for the dominant hand (r = 0.482) in males, as well as CMJ (r = 0.602) in females, compared to PhA of the whole body. CONCLUSION: PhA of the whole body was positively related to fat-free mass, body mass index, body fat %, and lower- and upper-limbs strength in handball athletes. Segmental PhA might be used as a tool for estimating lower and upper limbs performance considering the sex, in preference to the PhA of the whole body.

Phase Angle in Head and Neck Cancer: A Sex-Differential Analysis from Biological and Clinical Behavior to Health-Related Quality of Life.

Head and neck cancer (H&NC) is a diverse category of tumors related to malignancies in the common aerodigestive pathway, with high metabolic rate, poor nutritional and treatment outcomes, and elevated mortality despite the best standard treatment. Herein, we focus on determining how the phase angle (PA) differs across sex as a predictor of poor prognosis, low quality-of-life (QoL) scores, and mortality in patients with head and neck cancer. This follow-up study presents a sex-differential analysis in a prospective cohort of 139 head and neck cancer patients categorized by sex as male (n = 107) and female (n = 32). Patients were compared in terms of nutritional, biochemical, and quality-of-life indicators between low and normal PA in women (<3.9° (n = 14, 43.75%) and ≥3.9°) and men (<4.5° (n = 62, 57.9%) and ≥4.5°). Our results show that most patients were in locally advanced clinical stages (women: n = 21 (65.7%); men: n = 67 (62.6%)) and that patients with low PA had a lower punctuation in parameters such as handgrip strength, four-meter walking speed, albumin, C-reactive protein (CRP), and CRP/albumin ratio (CAR), as well as the worst QoL scores in functional and symptomatic scales in both the male and female groups. A comparison between sexes revealed significant disparities; malnourishment and tumor cachexia related to an inflammatory state was more evident in the women's group.

External validation of BIA equations to estimate appendicular skeletal muscle mass in older adults: Importance of the bias analysis and derivation of correction factors to achieve agreement.

There are several equations based on bioelectrical impedance analysis (BIA) to estimate with high precision appendicular skeletal muscle mass (ASM). However, most of the external validation studies have reported that these equations are inaccurate or biased when applied to different populations. Furthermore, none of the published studies has derived correction factors (CFs) in samples of community-dwelling older adults, and none of the published studies have assessed the influence of the dual-energy X-ray absorptiometry (DXA) model on the validation process. This study assessed the agreement between six BIA equations and DXA to estimate ASM in non-Caucasian older adults considering the DXA model and proposed a CF for three of them. This analysis included 547 non-institutionalized subjects over 60 years old from the northwest of Mexico who were physically independent and without cognitive impairment: 192 subjects were measured using DXA Hologic, while 355 were measured by DXA Lunar. The agreement between each of the equations and DXA was tested considering the DXA model used as a reference method for the design of each equation, using the Bland and Altman procedure, a paired t test, and simple linear regression as objective tests. This process was supported by the differences reported in the literature and confirmed in a subsample of 70 subjects measured with both models. Only six published BIA equations were included. The results showed that four equations overestimated ASMDXA, and two underestimated it (p < 0.001, 95% CI for Kim's equation:-5.86--5.45, Toselli's:-0.51--0.15, Kyle's: 1.43-1.84, Rangel-Peniche's: 0.32-0.74, Sergi's: 0.83-1.23, and Yoshida's: 4.16-4.63 kg). However, Toselli's, Kyle's and Rangel-Peniche's equations were the only ones that complied with having a homogeneous bias. This finding allowed the derivation of CFs, which consisted of subtracting or adding the mean of the differences from the original equation. After estimating ASM applying the respective CF, the new ASM estimations showed no significant bias and its distribution remained homogeneously distributed. Therefore, agreement with DXA in the sample of non-Caucasian was achieved. Adding valid CFs to some BIA equations allowed to reduce the bias of some equations, making them valid to estimate the mean values of ASM at group level.

Agreement Between Body Composition Assessed by Bioelectrical Impedance Analysis and Doubly Labeled Water in Obese Women Submitted to Bariatric Surgery : Body Composition, BIA, and DLW.

INTRODUCTION: Bariatric surgery has a significant influence on body composition (BC), which should be monitored. However, there is a need to recommend low-cost practical methods, with good estimation of BC for class III obese and/or bariatric patients. OBJECTIVE: The aim of this study was to determine accuracy and agreement between BC assessed by direct segmental multifrequency bioelectrical impedance analysis (DSM-BIA) and doubly labeled water (DLW) as reference method. MATERIAL AND METHODS: Twenty class III obese women (age 29.3 ± 5.1 years; body mass index 44.8 ± 2.4 kg/m2) underwent Roux-en-Y gastric bypass surgery. BC (fat mass [FM], fat-free mass [FFM], and total body water [TBW]) was assessed by InBody 230 and DLW in the following periods: before and 6 and 12 months after surgery. Accuracy between the methods was evaluated by the bias and root mean square error. Pearson's correlation, concordance correlation coefficient (CCC), and Bland-Altman method were used to evaluate agreement between the methods. RESULTS: Correlations were significant (p < 0.001) and CCC was good/excellent between both methods for the evaluation of FM (r = 0.84-0.92, CCC = 0.84-0.95), FFM (r = 0.73-0.90, CCC = 0.68-0.80), and TBW (r = 0.76-0.91, CCC = 0.72-0.81) before and after bariatric surgery. In addition, no significant bias was observed between DSM-BIA and DLW for FM (mean error [ME] = - 1.40 to 0.06 kg), FFM (ME = 0.91-1.86 kg), and TBW (ME = 0.71-1.24 kg) measurements. CONCLUSION: The DSM-BIA was able to estimate the BC of class III obese women submitted to bariatric surgery with values consistent with those of the DLW method.

Bioimpedance as a tool for evaluating the body composition of suruvi (Steindachneridion scriptum) / Bioimpedância como ferramenta de análise da composição corporal do suruvi (Steindachneridion scriptum)

Bioelectrical impedance analysis (BIA) is regarded as an important tool for evaluating the body composition of different animals in a rapid, non-destructive, and low-cost manner. A South American fish species, Steindachneridion scriptum, known as suruvi, was selected for study in this investigation. A protocol to produce fish with different body composition was used to allow BIA to adequately predict the body composition of suruvi. The fish were fed twice each day with two different diets; a low lipid diet (8.90%), and a high lipid diet (18.68%). These dietary differences allowed suruvi specimens with different body compositions to be produced. The BIA readings were determined using a Quantum X Bioelectrical Body Composition Analyzer. Two readings (dorsal and ventral) were obtained for each fish. After BIA readings were obtained, the proximate composition of the fish bodies for each individual was determined. All of the study data were used to establish correlation equations between proximate analyses and BIA values. Strong correlations were found for S. scriptum. The highest correlations were obtained for the following pairs of quantities, using BIA data from dorsal readings: moisture and resistance in series (R2 = 0.87); protein and resistance in series (R2 = 0.87); and ash and reactance in parallel (R2 = 0.82). We conclude that BIA is an effective method in determining the body composition of S. scriptum without sacrificing the fish. However, to expand the use of this new technology it is important to define strict BIA protocols to guarantee accurate estimates.(AU)

A análise da impedância bioelétrica (BIA) é considerada uma importante ferramenta para avaliar a composição corporal de diferentes animais de uma maneira rápida, não-destrutiva e de baixo custo. A espécie Sul-americana Steindachneridion scriptum, popularmente conhecida como suruvi, foi selecionada para este estudo. Foi utilizado um protocolo para produzir peixes com distintas composições corporais, permitindo a validação da BIA para análise adequada da composição corporal do suruvi. Os peixes foram alimentados duas vezes ao dia com duas dietas diferentes: uma de baixo teor lipídico (8,90%) e outra de alto teor lipídico (18,68%). Essa diferença nas dietas possibilitou a produção de indivíduos com diferentes composições corporais. As leituras da BIA foram determinadas utilizando-se o equipamento Quantum X Bioelectrical Body Composition Analyzer. Duas leituras (dorsal e ventral) foram obtidas para cada peixe. Após as leituras, para cada peixe individualmente, a composição proximal dos peixes foi determinada. Todos os dados obtidos foram utilizados para estabelecer as equações de correlação entre as análises proximais e os valores da BIA. Fortes correlações foram encontradas para S. scriptum. As maiores correlações foram obtidas para as análises dorsais a seguir: umidade e resistência em série (R2 = 0,87); proteína e resistência em série (R2 = 0,87); cinzas e reactância em paralelo (R2 = 0,82). Pode-se concluir que o método BIA é eficiente em determinar a composição corporal do suruvi S. scriptum sem sacrificar o animal. No entanto, para expandir o uso desta nova tecnologia é necessário definir protocolos rigorosos para garantir estimativas precisas.(AU)

Bioimpedance as a tool for evaluating the body composition of suruvi (Steindachneridion scriptum) / Bioimpedância como ferramenta de análise da composição corporal do suruvi (Steindachneridion scriptum)

Abstract Bioelectrical impedance analysis (BIA) is regarded as an important tool for evaluating the body composition of different animals in a rapid, non-destructive, and low-cost manner. A South American fish species, Steindachneridion scriptum, known as suruvi, was selected for study in this investigation. A protocol to produce fish with different body composition was used to allow BIA to adequately predict the body composition of suruvi. The fish were fed twice each day with two different diets; a low lipid diet (8.90%), and a high lipid diet (18.68%). These dietary differences allowed suruvi specimens with different body compositions to be produced. The BIA readings were determined using a Quantum X Bioelectrical Body Composition Analyzer. Two readings (dorsal and ventral) were obtained for each fish. After BIA readings were obtained, the proximate composition of the fish bodies for each individual was determined. All of the study data were used to establish correlation equations between proximate analyses and BIA values. Strong correlations were found for S. scriptum. The highest correlations were obtained for the following pairs of quantities, using BIA data from dorsal readings: moisture and resistance in series (R2 = 0.87); protein and resistance in series (R2 = 0.87); and ash and reactance in parallel (R2 = 0.82). We conclude that BIA is an effective method in determining the body composition of S. scriptum without sacrificing the fish. However, to expand the use of this new technology it is important to define strict BIA protocols to guarantee accurate estimates.

Resumo A análise da impedância bioelétrica (BIA) é considerada uma importante ferramenta para avaliar a composição corporal de diferentes animais de uma maneira rápida, não-destrutiva e de baixo custo. A espécie Sul-americana Steindachneridion scriptum, popularmente conhecida como suruvi, foi selecionada para este estudo. Foi utilizado um protocolo para produzir peixes com distintas composições corporais, permitindo a validação da BIA para análise adequada da composição corporal do suruvi. Os peixes foram alimentados duas vezes ao dia com duas dietas diferentes: uma de baixo teor lipídico (8,90%) e outra de alto teor lipídico (18,68%). Essa diferença nas dietas possibilitou a produção de indivíduos com diferentes composições corporais. As leituras da BIA foram determinadas utilizando-se o equipamento Quantum X Bioelectrical Body Composition Analyzer. Duas leituras (dorsal e ventral) foram obtidas para cada peixe. Após as leituras, para cada peixe individualmente, a composição proximal dos peixes foi determinada. Todos os dados obtidos foram utilizados para estabelecer as equações de correlação entre as análises proximais e os valores da BIA. Fortes correlações foram encontradas para S. scriptum. As maiores correlações foram obtidas para as análises dorsais a seguir: umidade e resistência em série (R2 = 0,87); proteína e resistência em série (R2 = 0,87); cinzas e reactância em paralelo (R2 = 0,82). Pode-se concluir que o método BIA é eficiente em determinar a composição corporal do suruvi S. scriptum sem sacrificar o animal. No entanto, para expandir o uso desta nova tecnologia é necessário definir protocolos rigorosos para garantir estimativas precisas.

Bioimpedance as a tool for evaluating the body composition of suruvi (Steindachneridion scriptum)

Abstract Bioelectrical impedance analysis (BIA) is regarded as an important tool for evaluating the body composition of different animals in a rapid, non-destructive, and low-cost manner. A South American fish species, Steindachneridion scriptum, known as suruvi, was selected for study in this investigation. A protocol to produce fish with different body composition was used to allow BIA to adequately predict the body composition of suruvi. The fish were fed twice each day with two different diets; a low lipid diet (8.90%), and a high lipid diet (18.68%). These dietary differences allowed suruvi specimens with different body compositions to be produced. The BIA readings were determined using a Quantum X Bioelectrical Body Composition Analyzer. Two readings (dorsal and ventral) were obtained for each fish. After BIA readings were obtained, the proximate composition of the fish bodies for each individual was determined. All of the study data were used to establish correlation equations between proximate analyses and BIA values. Strong correlations were found for S. scriptum. The highest correlations were obtained for the following pairs of quantities, using BIA data from dorsal readings: moisture and resistance in series (R2 = 0.87); protein and resistance in series (R2 = 0.87); and ash and reactance in parallel (R2 = 0.82). We conclude that BIA is an effective method in determining the body composition of S. scriptum without sacrificing the fish. However, to expand the use of this new technology it is important to define strict BIA protocols to guarantee accurate estimates.

Resumo A análise da impedância bioelétrica (BIA) é considerada uma importante ferramenta para avaliar a composição corporal de diferentes animais de uma maneira rápida, não-destrutiva e de baixo custo. A espécie Sul-americana Steindachneridion scriptum, popularmente conhecida como suruvi, foi selecionada para este estudo. Foi utilizado um protocolo para produzir peixes com distintas composições corporais, permitindo a validação da BIA para análise adequada da composição corporal do suruvi. Os peixes foram alimentados duas vezes ao dia com duas dietas diferentes: uma de baixo teor lipídico (8,90%) e outra de alto teor lipídico (18,68%). Essa diferença nas dietas possibilitou a produção de indivíduos com diferentes composições corporais. As leituras da BIA foram determinadas utilizando-se o equipamento Quantum X Bioelectrical Body Composition Analyzer. Duas leituras (dorsal e ventral) foram obtidas para cada peixe. Após as leituras, para cada peixe individualmente, a composição proximal dos peixes foi determinada. Todos os dados obtidos foram utilizados para estabelecer as equações de correlação entre as análises proximais e os valores da BIA. Fortes correlações foram encontradas para S. scriptum. As maiores correlações foram obtidas para as análises dorsais a seguir: umidade e resistência em série (R2 = 0,87); proteína e resistência em série (R2 = 0,87); cinzas e reactância em paralelo (R2 = 0,82). Pode-se concluir que o método BIA é eficiente em determinar a composição corporal do suruvi S. scriptum sem sacrificar o animal. No entanto, para expandir o uso desta nova tecnologia é necessário definir protocolos rigorosos para garantir estimativas precisas.

Total body water and failure to control blood pressure by medication in hemodialysis patients.

BACKGROUND: Volume overload is the main factor responsible for the pathogenesis of hypertension in dialysis patients. Few studies have evaluated the interpretation of the parameters obtained by bioelectrical impedance (BIA) to manage these patients. The aim of this study was to assess the best cutoff level of volume overload obtained by BIA able to predict the absence of hypertension control in hemodialysis patients. METHODS: Volume overload was calculated as the difference between total body water (TBW) measured by bioimpedance and TBW estimated by the Watson formula in chronic stable hemodialysis patients. Inadequate control of blood pressure (BP) was defined as the mean of measurements obtained before five hemodialysis sessions ≥140 × 90 mm Hg. The best cutoff level of volume overload assessed by BIA able to predict the absence of BP control in patients on chronic hemodialysis was determined by the receiver operating characteristic (ROC) curve using the Youden method. RESULTS: We included 205 patients, 53% male, aged 56 ± 14.5 years. The largest area under the ROC curve was found for predialysis volume overload (0.660, 95% CI 0.556-0.765, p = 0.004). The ROC curve of postdialysis volume overload also reaches statistical significance. The best cutoff point was found for predialysis volume overload ≥1.4 liters with a sensitivity of 69% and a specificity of 67%. CONCLUSION: The association of TBW and inadequate BP control highlights the importance of volume management in hemodialysis patients. Predialysis volume overload of 1.4 liters was the parameter that best discriminated the presence of inadequate BP control.

Associação entre ângulo de fase, PRISM I e gravidade da sepse / Association between phase angle, PRISM I and sepsis severity

JUSTIFICATIVA E OBJETIVOS: Ângulo de fase (AF) é a diferença entre a voltagem e a corrente e pode ser usado como indicador de massa celular corporal. Estudos clínicos mostram que baixos AF estão associados com morbidade e mortalidade em pacientes críticos. O objetivo deste estudo foi conhecer a relação entre AF e o escore pediátrico de risco de mortalidade (PRISM I) em pacientes pediátricos sépticos críticos, associando esse indicador c om a gravidade da sepse. MÉTODO: Estudo transversal realizado na Unidade de Terapia Intensiva (UTI) Pediátrica do Instituto Fernandes Figueira. Os pacientes foram caracterizados de acordo com faixa etária, sexo, gravidade da sepse, etiologia da insuficiência respiratória, escore de PRISM I, grau de disfunção de múltiplos órgãos e sistemas (DMOS). A análise de bioimpedância elétrica (BIA) foi realizada em todos os pacientes e, através da razão dos valores de reactância (Xc) e resistência (R), foi calculado o AF (AF = arco-tangente da reactância/resistência x 180º /Pi). RESULTADOS: Foram avaliados 75 pacientes, sendo 68 (90,7 por cento) com sepse. A incidência de choque séptico foi 39,7 por cento, sepse grave 42,6 por cento e sepse 17,6 por cento. Não houve diferença estatística significativa entre as médias de ângulo de fase e as categorias de PRISM I, porém observou-se uma relação inversa entre os valores de AF e as categorias de PRISM I, DMOS e tempo de internação. Os valores mais baixos de AF (1,5º-2,2º) foram observados no maior escore de PRISM I (> 30 por cento). CONCLUSÕES: Os pacientes pediátricos críticos apresentaram baixos valores de angulo de fase, portanto deve ter a sua importância prognóstica estudada.

BACKGROUND AND OBJECTIVES: Phase angle (PA) is the difference between voltage and current and can be used as an indicator of body cell mass. Clinical studies show that low phase angle is associated with morbidity and mortality of critical patients. The purpose of this study was to know the relation between phase angle and the Pediatric Risk of Mortality I (PRISM I) score, associating this score with the severity of sepsis. METHODS: A transversal study was performed at the Pediatric Intensive Care Unit (PICU) in Instituto Fernandes Figueira. The patients were classified according to age, gender, sepsis severity, cause of respiratory failure, PRISM I score, multiple organ dysfunction syndromes (MODS). Electrical bioimpedance analysis (BIA) was performed in all patients. Phase angle was calculated directly from reactance (Xc) and resistance (R). AF = arc-tangent reactance/resistance x 180º/Pi. RESULTS: 75 patients (68 septic) were evaluated. The incidence of septic shock was 39.7 percent, severe sepsis 42.6 percent and sepsis 17.6 percent. There was no significative statistical difference between the mean values of BIA and the categories of PRISM I, MODS, or the length of stay the PICU. The PA's lowest values (1.5º-2.2º) were associated to the greatest PRISM's scores (> 30 percent). CONCLUSIONS: Pediatric critical patients show low phase angle values, which might have prognostic implication.