Bioimpedância elétrica e sua aplicação em avaliação nutricional

Phase angle is a predictor of overall 5-year survival after head and neck cancer surgery

OBJECTIVE

To evaluate the ability of the variables Muscle Mass percentage (%MM), Body Fat percentage (%BF), Phase Angle (PhA), and Standardized Phase Angle (SPhA) to predict overall survival rates in individuals with surgically treated HNC.

METHODS

A prospective cohort study of surgically treated HNC patients was carried out between 2017 and 2022 at a cancer referral center in Feira de Santana, Bahia. All subjects were seen by an experienced dietitian the week before surgery. During this visit, patients had their sociodemographic and clinical data collected, as well as anthropometric measurements (weight and height) and BIA variables. In this study, postoperative overall 5-year survival was defined as the time in months between the date of surgery and the date of death, regardless of the cause of death. Patients were followed up after surgery until death.

RESULTS

Seventy-eight older adult patients were consecutively included. Patients had a median age of 65.5-years, were mostly men (83.3%), and most had low education levels (62.3%) and low household income, ranging from zero (19.2%) to the minimum wage (60.2%). They were mostly alcohol drinkers (91%) and tobacco smokers (87.2%). Glottic cancer was diagnosed in 48.7% of patients, with 44.8% of cases with stage-IV disease. Forty (51.2%) deaths were recorded in the follow-up period, with a median survival time of 39 months. Variables %MM, %BF, and SPhA were not significantly different between groups (alive vs. dead patients). PhA was considered an independent predictor of overall survival, with an accuracy of 69% (95% CI 0.57‒0.80). When comparing survival curves, patients with a preoperative PhA < 6.8° were more than twice as likely to die during follow-up (HR = 2.38; p =  0.02; 95% CI 1.14‒4.97).

CONCLUSION

Out of the assessed BIA variables, preoperative PhA was considered a good predictor of overall survival after HNC surgery.

LEVEL OF EVIDENCE: 3

Phase angle and anthropometric indicators of cardiometabolic risk in children and adolescents

RATIONALE/OBJECTIVE

The phase angle (PhA) is a measurement obtained from the resistance and reactance found in the bioelectrical impedance examination and is useful in assessing nutritional status and in assessing cardiometabolic diseases. Therefore, the objective was to correlate the phase angle to the anthropometric variables of cardiometabolic risk (CMR) in children and adolescents.

SUBJECTS/METHODS

Weight, height, body mass index (BMI), waist circumference (WC) and neck circumference (NC), waist-to-height ratio (WHtR), and PhA of 1231 children and adolescents aged between 5 and 18 years were assessed. PhA was assessed in tertiles and CMR was identified using the anthropometric variables BMI, WC, NC, and WHtR. Linear regression models were used to verify the association between PhA tertiles and CMR anthropometric variables, stratified by sex.

RESULTS

No relationship was found between PhA and CMR variables in children. In adolescents, lower values of NC (β = -0.019, p = 0.005) and BMI (β = -0.025, p = 0.023) were found in boys, WC (β = -0.017, p = 0.020), WHtR (β = -0.017, p = 0.020), NC (β = -0.011, p = 0.027) and BMI (β = -0.026, p = 0.009) in girls when they were in tertile 1 when compared to tertile 3 of the PhA, even after adjusting for age.

CONCLUSION

The PhA was directly associated with CMR in the assessed adolescents.

Body Composition and Phase Angle: How to Improve Nutritional Evaluation in Juvenile Dermatomyositis Patients

(1) Background: This study aimed to assess body composition (BC) using bioelectrical impedance and food intake in juvenile dermatomyositis (JDM) patients. Associations between BC and physical activity, disease activity/cumulative damage and health-related quality of life parameters were also evaluated; (2) Methods: This was a cross-sectional study with 30 consecutive JDM patients (18 female and 12 male) and 24 healthy volunteers (14 female and 10 male) of both sexes followed at our pediatric rheumatology unit. The gathering of anthropometric and dietary data, and the performance of physical activity and bioelectrical impedance were undertaken in face-to-face meetings and through questionnaires. Clinical and therapeutic data were collected from medical records according to information from routine medical appointments; (3) Results: The frequency of high/very high body fat was significantly higher in controls compared with JDM patients (66.7% vs. 91.7%; p = 0.046). The median phase angle was significantly lower in patients compared with controls (5.2 ± 1.3 vs. 6.1 ± 1.0; p = 0.016). Body fat and lean mass were positively correlated with disease duration (rs = +0.629, p < 0.001 and rs = +0.716, p < 0.001, respectively) and phase angle (PhA) (rs = +0.400, p = 0.029 and rs = +0.619, p < 0.001, respectively). JDM patients with PhA ≥ 5.5 presented higher lean mass when compared with patients with PhA < 5.5 (p = 0.001); (4) Conclusions: Bioelectrical impedance can be a useful auxiliary exam in the medical and nutritional follow-up of JDM patients, because it seems to impact functional ability. These findings may assist professionals when advising JDM patients about the importance of physical activity and healthy eating in the preservation of lean mass.

Application of bioelectrical impedance in newborns: an integrative review

OBJECTIVE

the objective of this study was to identify the use of bioelectrical impedance in newborns (NB), as this is an easy-to-apply and non-invasive method of measurement that can be used for distinguishing fat-free mass (FFM), fat mass (FM), and total body water (TBW).

METHOD

this was an integrative review of the literature using the PUBMED/MEDLINE, EMBASE, Web of Science, and Virtual Health Library databases to search for original articles between 2010-2020. A total of 900 articles were retrieved; after checking for duplicity and applying the eligibility criteria, 9 were further analyzed.

RESULTS

about the results, five studies used single frequency bioimpedance, with a specific population of neonates, preterm and/or full term, and different clinical conditions. Resistance was the most studied bioelectric indicator, the phase angle is little explored, and four studies investigated body composition (FFM, FM and TBW). Studies found that preterm newborns had lower amounts of TBW, FFM, and FM than term newborns, and there were differences in body composition between sex. The phase angle was lower for preterm newborns and fed babies with high protein formulas had increases in the FFM.

CONCLUSION

there is a need for multicenter studies to define standardized methods to be used with this public.

Genotyped indigenous Kiwcha adults at high altitude are lighter and shorter than their low altitude counterparts

Background

Anthropometric measures have been classically used to understand the impact of environmental factors on the living conditions of individuals and populations. Most reference studies on development and growth in which anthropometric measures were used were carried out in populations that are located at sea level, but there are few studies carried out in high altitude populations.

Objective

The objective of this study was to evaluate the anthropometric and body composition in autochthonous Kiwcha permanently living at low and high altitudes.

Methodology

A cross-sectional study of anthropometric and body composition between genetically matched lowland Kiwcha from Limoncocha (n = 117), 230 m in the Amazonian basin, and high-altitude Kiwcha from Oyacachi (n = 95), 3800 m in Andean highlands. Student’s t-test was used to analyze the differences between continuous variables, and the chi-square test was performed to check the association or independence of categorical variables. Fisher’s exact test or Spearman’s test was used when the variable had evident asymmetries with histograms prior to the selection of the test.

Results

This study shows that high altitude men are shorter than their counterparts who live at low altitude, with p = 0.019. About body muscle percentage, women at high altitudes have less body muscle percentage (− 24.8%). In comparison, men at high altitudes have significantly more muscle body mass percentage (+ 13.5%) than their lowland counterparts. Body fat percentage was lower among low altitude women (− 15.5%), and no differences were found among men.

Conclusions

This is the first study to be performed in two genotyped controlled matching populations located at different altitudes to our best knowledge. The anthropometric differences vary according to sex, demonstrating that high altitude populations are, in general, lighter and shorter than their low altitude controls. Men at high altitude have more muscled bodies compared to their lowland counterparts, but their body age was older than their actual age.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40101-022-00280-6.

Efficacy of neuromuscular electrical stimulation with combined low and high frequencies on body composition, peripheral muscle function and exercise tolerance in patients with chronic kidney disease undergoing haemodialysis: a protocol for a randomised, double-blind clinical trial

INTRODUCTION

Neuromuscular electrical stimulation (NMES) as an adjunctive strategy to increase isolated muscular strength or endurance has been widely investigated in patients with chronic kidney disease (CKD) undergoing haemodialysis (HD). However, the efficacy of combined low and high frequencies, to improve both muscular strength and endurance, is unknown. This trial aims to evaluate the efficacy of this combined NMES strategy in this population.

METHODS AND ANALYSIS

This is a randomised controlled trial with blinded assessments and analysis. A total of 56 patients with CKD undergoing HD will be recruited and randomised to an NMES protocol. The evaluations will be performed on three different days at baseline and after 24 sessions of follow-up. Assessments will include the background, insulin-like growth factor, lactate measurement, malnutrition and inflammation score evaluation, an electrical bioimpedance examination, global muscular evaluation by means of the Medical Research Council scale, handgrip strength evaluation, muscular isokinetic evaluation of lower limbs, 6 min step test performance and quality of life (QoL) questionnaire with emphasis on physical function. The patients will be allocated in one of the following four groups: 1) combined low and high frequencies; 2) low frequency; 3) high frequency; and 4) sham stimulation with minimal intensity to generate only sensory perception (with no visible contraction). In all groups, the intensity throughout the session will be the highest tolerated by patient (except for control group). The primary endpoint is the change of peripheral muscle function (muscular strength and endurance). The secondary endpoints will be the changes of body composition; muscle trophism; exercise tolerance; QoL; and nutritional, inflammatory, and metabolic markers. The findings of this study are expected to provide valuable knowledge on how to optimise the NMES intervention, with improvements in both muscle strength and endurance.

ETHICS AND DISSEMINATION

This protocol has been approved by the Ethics Committee on Research with Humans of Hospital Sírio-Libanês (approval no. 24337707). Written informed consent will be obtained from each participant. The results of the study will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03779126.

Association between phase angle and adverse clinical outcomes in hospitalized patients with COVID-19: A systematic review

Phase angle, obtained by bioelectrical impedance, is an indicator of cellular integrity and has been proposed as a prognostic parameter in patients who are critically ill. This systematic review aimed to evaluate the association between phase angle and adverse clinical outcomes in hospitalized patients with coronavirus disease–2019 (COVID‐19). An extensive literature search was performed in the MEDLINE/PubMed, Embase, and Web of Science databases, with interest in observational studies evaluating the association between phase angle and adverse clinical outcomes in individuals aged ≥18 years hospitalized with COVID‐19. Studies were independently selected by two reviewers, according to eligibility criteria. Subsequently, data were extracted and presented in a qualitative synthesis. The evaluation of the quality of the studies was performed according to the Newcastle‐Ottawa scale. The full methodology was published in PROSPERO (ID CRD42022306177). A total of 392 articles were identified, resulting in seven selected studies, of which six were prospective cohorts and one was retrospective. In the quality assessment, six studies obtained scores equal to or greater than seven, indicating a low risk of bias. A total of 750 participants composed the samples of the selected studies. Five studies reported an independent association between phase angle and adverse clinical outcomes during hospitalization for COVID‐19, with emphasis on prolonged hospitalization and mechanical ventilation and higher mortality in patients with a lower phase angle. Thus, phase angle measurement can be useful in the early identification of risks in patients hospitalized with COVID‐19, for the purpose of adequacy of clinical management.

Nutritional status and eating habits of patients with hereditary ataxias: a case-control study

INTRODUCTION

Hereditary Ataxias (HAs) comprise a wide spectrum of genetically determined neurodegenerative diseases with progressive ataxia as the main symptom. Few studies have evaluated nutritional profile in HA patients and most of these focused on specific ataxia subtypes. The objectives of this study were: (1) to investigate whether hereditary ataxias were associated with changes in energy expenditure, body composition and dietary intake; (2) to verify differences in these variables according to ataxia subtype, sex, age, and disease severity.

METHODS

Thirty-eight hereditary ataxia patients from two neurology centers in Northeastern Brazil and 38 controls were evaluated. Body composition was assessed with bio-impedance analysis and dietary intake was estimated with a validated questionnaire (24-hour dietary recall).

RESULTS

Mean body mass index (BMI) was lower in HA compared to controls (p = 0.032). Hereditary ataxia patients showed lower protein intake, higher frequency of dysphagia and higher incidence of nausea and diarrhea. The difference in average estimated caloric intake did not reach statistical significance (2359kcal ± 622 in patients × 2713kcal ± 804 in controls, p = 0.08). Disease severity measured by the SARA scale was not associated with BMI, nor was ataxia subtype (autosomal dominant × non-autosomal dominant ataxias).

CONCLUSION

Hereditary ataxia patients have lower BMI compared to healthy controls. There was no difference in this cohort between dominant or non-dominant ataxia regarding BMI. Weight loss may be a common finding among hereditary ataxias and may affect the quality of life in these patients.

Evaluation of the bioimpedance technique in newborns with a focus on electrode positioning: A prospective, randomized, crossover study

BACKGROUND

Bioelectrical impedance analysis (BIA) is a good alternative for assessing total body water in newborns. However, the lack of standardization of the method for its use in the neonatal population raises doubts about its reliability and external validation.

OBJECTIVE

To compare resistance (R) and reactance (Xc) values measured by BIA with electrodes placed in the anatomical position and with electrodes placed at 5-cm intervals.

METHOD

Prospective, randomized, crossover study, in which R and Xc values were measured using monofrequency BIA. The choice of the first position of the electrodes to be analyzed in each NB was performed by a simple randomization, and subsequent measurements were performed in rapid succession. The calculated sample size was 203 evaluations. The paired t test was used to compare the means of R and Xc, and the Bland-Altman plot and linear regression were used to analyze how much the measured values were influenced by the electrode position.

RESULTS

Significant differences were found in the R (855.25 ± 147.79 vs 618.95 ± 93.28 Ω) and Xc (50.94 ± 17.34 vs 39.76 ± 18.35 Ω) values measured with electrodes in the anatomical position and at 5-cm intervals, respectively. The electrodes in the anatomical position produced R and Xc values 37.7% and 16.6%, respectively, higher on average when compared with 5-cm intervals.

CONCLUSIONS

The distance between the electrodes influences the measurement of R and Xc by BIA. These results highlight the importance of defining a standard for the placement of electrodes in newborns for the use of these measures in neonatal clinical practice.

Comparison of Bioelectrical Impedance Vector Analysis (BIVA) to 7-point Subjective Global Assessment for the diagnosis of malnutrition

INTRODUCTION

Bioelectrical impedance vector analysis (BIVA) is a non-invasive and low-cost strategy. The methods used to assess malnutrition in patients undergoing HD are still a challenge. The aim of the present study was to compare BIVA to 7-Point Subjective Global Assessment (7-point SGA) to identify malnutrition. We also investigated the sensitivity and specificity of the previously proposed cutoffs point for BIVA parameters.

METHODS

Patients of both sexes, over 20 years of age, on HD treatment were included. Anthropometric parameters, laboratory data, and bioelectrical impedance analysis (BIA) were evaluated. Values of resistance (R) and reactance (Xc) obtained by mono-frequency BIA were normalized to body height (H) to generate a graph of the bioimpedance vector with the BIVA software. The analysis of the area under the receiver operating curve ROC (AUC) was performed.

RESULTS

Among the included 104 patients, the mean age was 51.70 (±15.10) years, and 52% were male. The BIVA had a sensitivity of 35% for diagnosing malnutrition. The specificity of BIVA for identifying the well-nourished patients was 85.7%. The diagnostic accuracy between the BIVA and 7-point SGA was AUC=0.604; 95%CI 0.490-0.726, higher than the previously established cutoff values (AUC=0.514; 95%CI: 0.369-0.631). The 95% confidence ellipses did not overlap (p<0.05).

CONCLUSION

Our study showed low accuracy of BIVA for diagnosing malnutrition using a 7-point SGA as a reference standard. However, it is a complementary method for assessing nutritional status as it provides data on cellularity and hydration, which are important aspects for the HD population.

Sarcopenia

Objective: To assess the prevalence of sarcopenia and associated factors among older women from the local community and older women living in Long-Term Care (LTC) institutions.Methods: A cross-sectional study conducted with 423 older women aged 60 or more, from the local community and older women aged 60 or more, living in LTC institutions. Sarcopenia was defined, according to the consensus of the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), including three criteria: low muscle strength (LMS) (<16kg); low muscle mass (LMM) (≤6.75kg/m2) assessed by a skeletal muscle mass index, and low physical performance (LPP) (≤0,8m/s) assessed by gait speed test. Older women who only showed LMS were considered to have pre-sarcopenia, those with LMS associated with LMM were diagnosed with sarcopenia and those who met all three criteria, were diagnosed with severe sarcopenia.Results: Among the community-dwelling older women, the prevalence of sarcopenia was 2.0% (from 60 to 69), 8.6% (from 70 to 79) and 12.9% (80 or more) and among the ones living in LTC Institutions, 3.3% (from 60 to 69), 14.8% (from 70 to 79) and 34.2% (80 or more). After multivariate logistic regression, age and low body mass index (BMI) were associated with sarcopenia in both groups.Conclusion: The prevalence of sarcopenia is higher among LTC older women. However, this is not an independent factor. In addition, regardless of residence, low BMI and advanced age are predictive for sarcopenia.

The use of bioelectrical impedance vector analysis for a nutritional evaluation of older adults in the community

INTRODUCTION

The body composition of an older adult person is characterized by an increase in body fat, as well as by a reduction in both muscle mass and total body water. The bioelectrical impedance vector analysis (BIVA) overcomes the limits imposed by bioelectrical impedance, since it only requires the resistance (R) and reactance (Xc) values, standardized by the individual's height, which makes the method more individualized and accurate. The aim of this study was to evaluate the body composition using the BIVA of the community-living older adults, with regard to sex and body mass index (BMI) classification, and compare the results with the reference population.

METHODS

Cross-sectional study with the community-living older adults of both sexes. Bioimpedance was carried out and the R and Xc data analyzed, based on height, and plotted on RXc graphs.

RESULTS

One hundred and forty-four older adults (n = 33 men; n = 111 women; mean age of 80.2 ± 9.2 years) participated in the study. Low weight (<23 kg/m²) was the most prevalent in BMI classification. The older adult women presented a higher average BMI, body fat percentage and R/Height values, while the older adult men presented a higher average for fat-free mass and the phase angle (p < 0.05). The older adult, regardless of their BMI, located in the right quadrant, indicated cachexia; those with low weight were dehydrated, and those with overweight (BMI ≥ 28 kg/m²) presented hyperhydration.

CONCLUSION

The majority of the older adults with normal weight or overweight has impedance vectors indicating loss of muscle mass and water imbalance (dehydration or hyperhydration).

Cell integrity indicators in university athletes: comparison among playing positions in indoor football

BACKGROUND

The aim of this study was to compare cell integrity indicators according to the playing position in university indoor football athletes.

METHODS

The sample consisted of 34 university athletes (20 female and 14 male). Dependent variables were cell integrity indicators: total body water (TBW), intracellular water (ICW), extracellular water (ECW), ECW/ICW ratio, body cell mass (BCM), ECW/BCM ratio, phase angle (PhA), resistance (R), Xc (reactance) and impedance (Z), evaluated by the electrical bioimpedance method. Independent variable was the playing position: goalkeeper (a), defender (a), winger (left and right) and pivot collected through questionnaire. Control variables were age, time of sport practice, participation in competitions per year and training load obtained by applying the anamnesis form, and body fat and fat and bone-free mass were obtained through dual emission X-ray absorptiometry (DXA). Covariance analysis (ANCOVA) was used, with post-roc Tukey's test, to identify difference between groups, with p <0.05.

RESULTS

In the adjusted analysis, female athletes in the defense position had BCM values (31.1 ±2.1) higher than those in the wing position (25.8 ±1.1) (p <0.01). In males, pivots showed higher ICW values (31.47 ±0.77) when compared to defenders (25.7 ±0.8) (p = 0.02). In addition, goalkeepers had higher TBW values (52.7 ±2.5) compared to wingers (42.3 ±1.2) (p = 0.03).

CONCLUSIONS

Cell integrity indicators may vary according to the playing position in indoor football.

Analysis of Body Composition and Pain Intensity in Women with Chronic Pelvic Pain Secondary to Endometriosis

OBJECTIVE

 To determine the average body composition (percentage of body fat), the anthropometric markers, and the intensity of clinical pain in women with a clinical diagnosis of chronic pelvic pain (CPP) secondary to endometriosis.

METHODS

 A case-control study performed with 91 women, 46 of whom with CPP secondary to endometriosis and 45 of whom with CPP secondary to other causes. They underwent an evaluation of the anthropometric parameters by means of the body mass index (BMI), the perimeters (waist, abdomen, hip), and the percentage of body fat (%BF), which were assessed on a body composition monitor by bioimpedance; the intensity of the clinical pain was evaluated using the visual analog scale (VAS), and the symptoms of anxiety and depression, using the hospital's anxiety and depression scale (HAD).

RESULTS

 The groups did not differ in terms of mean age, BMI, %BF or regarding the available waist-to-hip ratio (WHR). The mean intensity of the clinical pain by the VAS was of 7.2 ± 2.06 in the group with CPP secondary to endometriosis, and of 5.93 ± 2.64 in the group with CPP secondary to other causes (p = 0.03), revealing significant differences between the groups.

CONCLUSION

 We concluded that, despite the difference in the pain score assessed between the two groups, there was no difference regarding body composition and anthropometry.

Can Phase Angle in Newborns at Neonatal Intensive Care Units Be an Indicator of Mortality and Prognosis?

BACKGROUND

The bioelectrical impedance (BI) phase angle (PA), analyzed directly through BI analysis (BIA), is determined by tissue cellularity, representing a direct measure of cellular stability and, for this reason, has been studied and considered as an indicator of prognosis and nutrition status in adults and children.

OBJECTIVE

We aimed to determine if PA can be an indicator of mortality and prognosis in newborns admitted to the neonatal intensive care unit (NICU).

METHODS

Transversal study conducted at a public NICU in Curitiba, Paraná, Brazil. All newborns, preterm and term, were considered eligible for the study if admission to the NICU occurred by the first hour of life. The Score for Neonatal Acute Physiology II, as well as the Perinatal Extension version, were developed to assess the risk of mortality for all newborns, measured within 12 hours of admission. BIA measurements were conducted using the tetrapolar BioScan Maltron 916, with single-frequency (50 kHz) tetrapolar BI. PA was calculated as the arc tangent: (Xc/R) x 180°/π.

RESULTS

BIA was measured during the first 24 hours of admission for all newborns (n = 93), repeated between 24 and 48 hours (n = 79) and again after 7 days (n = 55), always when possible. PA measurements decreased in the first 48 hours in premature newborns, particularly among those who died. The premature newborns also showed a significant decrease from the first to the last PA measurement (P = .001). In addition, whereas full-term newborns showed an increase of PA at 1 week of life, preterm infants continued to have a decrease in values. For preterm newborns, PA measurements decreased and more sharply so for those who died. This result should be viewed with caution given the small number of deaths, but it should be investigated to understand the role of PA in the prognosis of NICU newborns.

CONCLUSIONS

The absolute value of PA during the first 24 hours of life was not a good marker for severity or mortality. However, the decrease of PA between different moments of evaluation was a good marker of severity. The decrease of PA in the first 48 hours in premature newborns, and that when the decrease is more pronounced, may be indicative of mortality. The difference in PA values between these newborns is probably a significant variable for mortality and prognosis and not a cutoff value.

Anthropometry, bioimpedance and densitometry: Comparative methods for lean mass body analysis in elderly outpatients from a tertiary hospital

OBJECTIVES

To evaluate lean mass index (LMI) measured by bioimpedance (BIA) and anthropometry compared to densitometry (DXA) in elderly outpatients from a tertiary care hospital.

METHODS

Participants were over 60-year-old men, presenting no dementia or disability, from a tertiary geriatric ambulatory. LMI obtained by BIA, anthropometry and DXA were submitted to Baumgartner, Janssen and Delmonico calculations respectively. Sarcopenia was calculated as LMI by DXA and handgrip strength. Data were analyzed by T student's test, ANOVA for repeated measures and pos hoc Bonferroni test, Pearson's correlation test, regression equation and Bland Altman analysis, ROC curve and contingency table 2 × 2 for sensitivity, specificity and predictive values.

RESULTS

A total of 92 participants completed the study. Most of them were married, aged 72.9 ± 6.6, lived a sedentary lifestyle, presented multiple morbidities, and in use of polypharmacy. Appendicular lean mass was lower in sarcopenic participants when compared to that in nonsarcopenic ones (20.2 kg/m² and 23 kg/m² respectively, p < 0.0001). BIA sensitivity, specificity and correlation to DXA were 37%, 98% and r = 0.81 (p < 0.001), and for anthropometry 67%, 92% and r = 0.77 (p < 0.0001) respectively. Bland Altman's analysis showed congruence between methods and DXA (anthropometry: bias = -0,05 ± 0,66, limits of agreement (LoA) = -1.37 and 1.26; BIA: bias = 2,2; LoA = 0,7 and 3,7).

CONCLUSION

Aging and multiple chronic and degenerative morbidities affect LM in vulnerable elderly patients. Both anthropometry and BIA, are accurate to measure LMI independently in this population but Anthropometry presented better agreement to DXA than Bioimpedance and has the advantage of lower price, easier application and cheaper equipment to be applied.

[Profile of body composition in women with class III obesity by multipolar bioimpedance method]

OBJECTIVE

To analyze a body composition profile in women with class III obesity using the multipolar bioimpedance method.

METHODS

Thirteen sedentary women aged between 20 and 40 years were evaluated.

RESULTS

The results show that the patients had a fat percentage of 51.9±1.50 % and lean mass of 48.1±1.50 %. Regarding fat mass and lean mass per body region, figures of 26.3±3.62kg and 26.2±2.91kg in the upper body, 9.1±0.06kg and 8.4±0.14kg in the lower limbs, and 3.3±0.02kg and 7.6±0.01kg in the upper limbs were obtained. Patients had a good symmetry between the left and right sides in both upper and lower limbs, besides of a muscular mass of 32.1±5.08kg, with a muscular mass index of 12.7±1.05kg/m2.

CONCLUSION

Higher fat accumulation was observed in the upper body region, followed by lower and upper limbs. Total muscular mass was apparently preserved, although sarcopenic obesity was not verified. Since this is a group of people that is still understudied, there is a need for further research on genetic and physical profile and caloric expenditure during exercise and rest.

Diagnostic Accuracy of Bioelectrical Impedance Analysis Parameters for the Evaluation of Malnutrition in Patients Receiving Hemodialysis

BACKGROUND

In the absence of a gold standard technique for assessing nutrition status in patients receiving hemodialysis (HD), we aimed to determine the diagnostic accuracy of single-frequency (50 kHz) bioelectrical impedance analysis parameters, resistance/height (R/H), reactance/height (Xc/H), and impedance/height (Z/H), and their cutoff points for malnutrition.

METHODS

The reference standards, Subjective Global Assessment (SGA), Malnutrition Inflammation Score, and Nutritional Risk Screening 2002, were performed at baseline and then once a year for 2 years. At least 2 assessments for each reference standard were performed during the monitoring period, and those patients who were assessed as malnourished on at least 2 consecutive occasions were classified as malnourished.

RESULTS

A total 101 patients receiving HD were evaluated. R/H and Z/H demonstrated low to moderate accuracy to diagnose malnutrition in men and low accuracy in women, whereas the accuracy of Xc/H was uncertain. The cutoff points of bioelectrical impedance vector analysis (BIVA) parameters, determined based on the SGA to maximize sensitivity and specificity simultaneously, were: R/H ≥330.05 and ≥420.92 ohms/m for men and women, respectively; Z/H ≥332.71 and ≥423.19 ohms/m for men and women, respectively. In men, sensitivity based on the cutoff points of R/H and Z/H together ranged from 73% to 89% and specificity ranged from 49% to 50%. In women, sensitivity ranged from 58% to 80% and specificity from 48% to 55%.

CONCLUSION

BIVA parameters demonstrated low to moderate accuracy in men and low accuracy in women for the diagnosis of malnutrition.

Prevalence, temporal trend and associated factors with excess body weight in mothers of children under five years

ABSTRACT Objective This study aims to evaluate the prevalence, temporal trends and associated factors with excess weight in mothers of children under five years of age. Methods This is a time-series study using data from two household surveys conducted in 2005 and 2015. A total of 1,436 mothers were evaluated in 2005, and 690 were evaluated in 2015. The dependent variables were excess body weight (Body Mass Index [BMI] ≥25.0kg/m2), high percentage of Body Fat (%BF ≥33%) and abdominal obesity (waist circumference >80cm). The independent variables were the socioeconomic and demographic factors. The changes that occurred between the two surveys were expressed in percentages, and the measure of association was the Prevalence Ratio, calculated by Poisson regression, in both the crude and multivariate analyses. Results There were increases of 33.2%, 59.2% and 31.0%, respectively, for the prevalence of excess weight (PR=1.33, 95% Confidence Interval [CI]:1.21-1.46), abdominal obesity (PR=1.59, 95% CI:1.43-1.77) and high %BF (PR=1.31, 95% CI:1.07-1.60). The factors independently associated with excess weight and abdominal obesity were the highest age group (>30 years), menarche ≤12 years and higher parity (>2 children). The same was observed for high %BF, except for the loss of significance in the adjusted analysis for the variable menarche ≤12 years. Conclusion The prevalence of high body adiposity is a problem of relevant importance in the studied population and has presented an upward trend in the last 10 years. Women over 30 years and with more than two children should be given priority in prevention and control.

Interference of heart and transcutaneous oxygen monitoring in the measurement of bioelectrical impedance analysis in preterm newborns

OBJECTIVE

To verify if the connection of electrodes for heart and transcutaneous oxygen monitoring interfere with the measurement of electrical bioimpedance in preterm newborns.

METHODS

This was a prospective, blinded, controlled, cross-sectional, crossover study that assessed and compared paired measures of resistance (R) and reactance (Xc) by BIA, obtained with and without monitoring wires attached to the preterm newborn. The measurements were performed in immediate sequence, after randomization to the presence or absence of electrodes. The sample size calculated was 114 measurements or tests with monitoring wires and 114 without monitoring wires, considering for a difference between the averages of 0.1 ohms, with an alpha error of 10% and beta error of 20%, with significance <0.05.

RESULTS

No differences were observed between the R (677.37±196.07 vs. 677.46±194.86) and Xc (31.15±9.36 vs. 31.01±9.56) values obtained with and without monitoring wires, respectively, with good correlation between them (R: 0.997 and Xc: 0.968).

CONCLUSION

The presence of heart and/or transcutaneous oxygen monitoring wires connected to the preterm newborn did not affect the values of R or Xc measured by BIA, allowing them to be carried out in this population without risks.

Effect of glycemic index on obesity control

OBJECTIVE

Evaluate the effect of glycemic index (GI) on biochemical parameters, food intake, energy metabolism, anthropometric measures and body composition in overweight subjects.

MATERIALS AND METHODS

Simple blind study, in which nineteen subjects were randomly assigned to consume in the laboratory two daily low GI (n = 10) or high GI (n = 9) meals, for forty-five consecutive days. Habitual food intake was assessed at baseline. Food intake, anthropometric measures and body composition were assessed at each 15 days. Energy metabolism and biochemical parameters were evaluated at baseline and the end of the study.

RESULTS

Low GI meals increased fat oxidation, and reduced waist circumference and HOMA-IR, while high GI meals increased daily dietary fiber and energy intake compared to baseline. There was a higher reduction on waist circumference and body fat, and a higher increase on postprandial fat oxidation in response to the LGI meals than after high GI meals. High GI meals increased fasting respiratory coefficient compared to baseline and low GI meals.

CONCLUSION

The results of the present study showed that the consumption of two daily low GI meals for forty-five consecutive days has a positive effect on obesity control, whereas, the consumption of high GI meals result has the opposite effect.

Nutritional status according to the stages of Alzheimer's disease

OBJECTIVE

To assess the nutritional status of Alzheimer's disease (AD) patients with no other associated dementia, according to disease stage.

DESIGN

Cross-sectional observational study.

SETTING

Neurobehavioral Diseases Outpatient Clinic, Clinical Hospital, Ribeirao Preto Medical School (University of São Paulo).

PARTICIPANTS

The sample consisted of 36 individuals of both genders with AD diagnosis, and no other associated type of dementia, in various stages of the disease, according to the Clinical Dementia Rating (CDR 0.5-3).

MEASUREMENTS

Nutritional status was evaluated using the Mini Nutritional Assessment (MNA) and anthropometric measurements such as weight, body mass index (BMI) and arm, waist, abdomen and hip circumferences. In addition, body composition was assessed by bioelectrical impedance analysis (BIA).

RESULTS

The mean age of the group was 74.2 ± 10.1 years, 72.2 % of them were women. The MNA showed that most of these individuals were at risk for malnutrition (55.5 %) and many of them (43.7 %) were underweight according to BMI. Data from BIA analysis revealed that 41.7 % of these individuals had a quantity of body fat classified as malnutrition and 11.1 % had a phase angle (PA) below recommended values for age group. There was a negative and significant correlation of lean mass and PA with age, and of global MNA evaluation with CDR, as well as a positive correlation of MNA total score with fat mass and BMI. Worse classifications of nutritional status obtained by MNA scores were also observed in the more severe stages of the disease, according to the CDR.

CONCLUSION

Patients with AD are mostly elderly with changes in body composition that are typical of aging, with signs of peripheral malnutrition and preservation of abdominal fat. However, greater impairment of general nutritional status was observed in the more advanced stages of AD, creating a situation of greater vulnerability for these patients.

Predictive capacity of different bioelectrical impedance analysis devices, with and without protocol, in the evaluation of adolescents

OBJECTIVE

this study was performed to determine the predictive capacity of four different bioelectrical impedance analysis (BIA) devices in the assessment of adolescents, with and without a protocol.

METHODS

a cross-sectional study was performed with 215 adolescents aged 10 to 14 years, of both genders, evaluated through anthropometry and body composition by dual energy X-ray absorptiometry (DXA) and by four different BIA devices, with and without a protocol. The following tests were used: Kolmogorov-Smirnov's, chi-squared, Student's t or Mann-Whitney's, Kruskal-Wallis's, Wilcoxon's, and kappa index. The ROC curves were constructed and the sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

of the 215 adolescents, 44.2% had excessive body fat. The tetrapolar BIA device equipped with eight tactile electrodes showed more sensitivity and results that were closer to those obtained by DXA (area under the ROC curve [AUC] = 0.964 with protocol and AUC = 0.973 without protocol, p < 0.001), as well as greater agreement (k = 0.67 with protocol and k = 0.63 without protocol, p < 0.001). The evaluation without protocol was similar to that by DXA in most investigated situations (p > 0.05).

CONCLUSION

BIA is capable of predicting alterations in adolescents' body composition. When it is impossible to perform the assessment with a protocol, its results may be useful in population studies.

Bioimpedância elétrica e gordura visceral: uma comparação com a tomografia computadorizada em adultos e idosos

OBJETIVO: Avaliar a associação entre bioimpedância elétrica (BIA) e gordura visceral (GV) em adultos e idosos. SUJEITOS E MÉTODOS: Estudo transversal, 191 indivíduos (52% mulheres, 49% idosos), estratificados por sexo, grupo etário e massa corporal. Obtiveram-se dados sobre tomografia computadorizada (área de GV) e BIA (percentual de gordura corporal total (%GCT-BIA), ângulo de fase, reactância e resistência). Análise estatística: Coeficiente de Correlação de Pearson, Anova, Qui-quadrado de Pearson, Curva ROC. RESULTADOS: Áreas de GV > 130 cm² foram mais observadas em idosos e em homens. Entre as mulheres adultas, mostrou-se correlação mais forte entre GV e %GCT-BIA. Os demais grupos apresentaram resultados semelhantes e correlações estatisticamente significantes. As correlações entre GV e ângulo de fase foram fracas e sem significância estatística. As análises da Curva ROC indicaram os seguintes %GCT-BIA que identificaram excesso de GV: homens: 21,5% (adultos), 24,25% (idosos); mulheres: 35,05% (adultas), 38,45% (idosas), com sensibilidade de 78,6%, 82,1%, 83,3%, 66,7% e especificidade de 70,6%, 62,5%, 79,1%, 69%, respectivamente. CONCLUSÃO: BIA apresentou satisfatória sensibilidade e especificidade para predizer GV, entretanto, outros aparelhos e técnicas devem ser investigados para melhorar essa predição.