Thiago Gonzalez Barbosa-Silva

Phase angle and its determinants in healthy subjects: influence of body composition

BACKGROUND The phase angle (PA) has been used as a prognostic marker in several clinical situations. Nevertheless, its biological meaning is not completely understood. OBJECTIVE We verified how body-composition components could explain the PA. DESIGN The trial was a cross-sectional study involving 1442 participants (women: 58.5%; Caucasian: 40.2%) from body-composition studies. Labeled tritium dilution and total-body potassium were used to estimate total-body water (TBW) and intracellular water (ICW), respectively. Extracellular water (ECW) and the ECW:ICW ratio were estimated from the difference and the ratio of these values. Fat-free mass (FFM) and fat mass (FM) were estimated with the use of dual-energy X-ray absorptiometry, underwater weighing (UWW), and TBW. The PA was estimated with the use of a single-frequency bioelectrical impedance analysis system. Correlations between the PA and all body-composition variables were evaluated. A multivariate linear regression analysis was performed to adjust for the effects of body-composition variables on the PA variability. All analyses were performed separately by sex. RESULTS Compared with men, women exhibited significantly larger ECW:ICW ratios and FM. The highest positive correlation was shown between the PA and FFM obtained with the use of UWW (both sexes). The highest negative correlation was shown between the PA and ECW:ICW ratios for both sexes. Age, race, height, ECW:ICW, and FFM from UWW were significant PA determinants in a multivariate linear regression model. Even after adjustment for all significant covariates, the explained PA variance was low (adjusted R(2) = 0.539 and 0.421 in men and women, respectively). The greatest impact on the total PA prediction in both men and women were age, FFM, and height. CONCLUSIONS Age is the most significant PA predictor in men and women followed by FFM and height. The ECW:ICW contribution may explain the association of the PA observed in the clinical setting and in people who are obese.

Prevalence of sarcopenia among community-dwelling elderly of a medium-sized South American city: results of the COMO VAI? study

There is insufficient data concerning sarcopenia prevalence in South America. The aim of this study was to estimate sarcopenia prevalence and its clinical subgroups in a Southern Brazilian city.

Adductor pollicis muscle: A study about its use as a nutritional parameter in surgical patients

BACKGROUND & AIMS Body composition is important to identify malnutrition, and several anthropometric measurements are used to estimate muscle mass in the clinical practice. This study aimed to assess the adductor pollicis muscle thickness (APMT), its covariates and association with malnutrition in hospitalized surgical patients. METHODS APMT was measured in 361 surgical patients in both dominant (DAPMT) and non-dominant (NDAPMT) sides. APMT values below the 5th percentile of reference values provided by a healthy population were considered as malnourished. Nutritional status was assessed by Subjective Global Assessment (SGA). The difference in APMT values among nutritional status categories was evaluated, and the association between malnutrition by SGA and APMT was estimated using multivariate linear regression. Sensitivity, specificity and positive and negative predictive values were also calculated. RESULTS Most patients were women (60.4%). APMT values were significantly different among SGA categories. Well-nourished patients had APMT values significantly higher compared to the ones with moderate or severe malnutrition by SGA, with no significant difference between APMT values in moderate or severe malnourished patients. Statistically significant associations between both DAPMT and NDAPMT below the 5th percentile and malnutrition and were found (RR = 3.99, CI 95% = 3.19-5.00; p < 0.001; and RR = 3.92; CI 95% = 3.10-4.96; p < 0.001; respectively). Gender, age, estimated weight and nutritional status were considered associated factors for APMT. APMT showed low sensitivity (DAPMT: 34.9%, NDAPMT: 37.7%) but high specificity (DAPMT: 98.7%, NDAPMT: 97.8%) to identify malnutrition. CONCLUSIONS APMT was significantly associated with nutritional status in a sample of surgical patients. The APMT seems to be a simple and useful anthropometric tool to confirm the diagnosis of malnutrition.

Is adductor pollicis muscle thickness a good predictor of lean mass in adults

Summary Background & aims Lean mass (LM) is an important parameter in clinical outcomes, which highlights the necessity of reliable tools for its estimation. The adductor pollicis muscle thickness (APMT) is easily accessible and suffers minimal interference from the adjacent subcutaneous fat tissue. Objective To assess the relationship between the APMT and LM in a sample of Southern Brazilian adults. Methods Participants were adults from the 1982 Pelotas (Brazil) Birth Cohort. LM was measured by dual energy X-ray absorptiometry (DXA). LM and lean mass index (LMI – LM divided by the square of height – kg/m2) were the outcomes. APMT was measured using a skinfold caliper. The mean of three measurements in the non-dominant hand was used in the analyses. APMT was described according to socio-demographic characteristics and nutritional status. The relationship between APMT and both LM and LMI was evaluated by correlation coefficient and linear regression using APMT as a single anthropometric parameter and also in addition to BMI. Results APMT was assessed in 3485 participants. APMT was higher in males, non-whites, less-schooled and obese individuals. APMT was moderately correlated to LM and LMI (ranged from 0.44 to 0.57). Correlation coefficients were higher for LMI as outcome and in females (LM: 0.51 and LMI: 0.57). APMT explained 19% and 26% of the variance in LM in males and females, respectively, whereas it explained 26% and 33% of the variance in LMI. APMT increased the prediction for LM in 3 and 4 percentage points in males and females, in comparison to explained by BMI. BMI explained 48% and 59% of the variance of LMI in males and females whereas APMT increased it to 51% and 62% for both sexes, respectively. Conclusions Results were not good enough to promote the APMT as a single predictor of LM or LMI in epidemiological studies. APMT has a little predictive capacity in estimating LM or LMI when BMI is also considered.

Estimation of body fat in adults using a portable A-mode ultrasound.

OBJECTIVE This study aimed to develop and validate equations to estimate body fat based on anthropometric measurements of subcutaneous fat thickness (SFT) and muscle thickness (MT) measured by A-mode ultrasound (BodyMetrix) in Brazilian adults. METHODS Individuals (n = 206) underwent air-displacement plethysmography for body composition assessment. Arm, thigh, and calf circumferences were also obtained. SFT from triceps, biceps, subscapular, abdominal, thigh, and calf regions and MT from triceps, biceps, thigh, and calf regions were measured by BodyMetrix. Prediction equations were developed by stepwise multiple linear regression using the circumferences, weight, height, SFT, and MT. Lins concordance correlation coefficient, mean difference, and 95% limits of agreement (95% LOA) were assessed in apparent and internal validity. RESULTS The prediction equation for whole-body fat for men included thigh circumference, triceps and thigh SFT, biceps MT, weight, and height. The equation for women included age, calf circumference, abdominal and calf SFT, weight, and height. The prediction equation overestimated mens whole-body fat by 0.5 percentual points, in average, and the lower and upper 95% LOA were -6.8% and 7.7%, respectively. For women, the prediction equation overestimated whole-body fat by 0.1 percentual points, in average. Lower and upper 95% LOA were -6.5% and 6.7%, respectively. Optimism-adjusted results using 500 repetitions with same size samples have shown similar results. Body fat extremes did not influence the whole-body fat estimation. CONCLUSIONS BodyMetrix A-mode ultrasound, in association with selected conventional anthropometric measurements, proved to be a reliable tool for the estimation of body fat percentage.

Falls among older adults in the South of Brazil: prevalence and determinants

OBJETIVO Avaliar a prevalencia e os fatores associados a ocorrencia de quedas em idosos. METODOS Estudo transversal com amostra representativa de 1.451 idosos residentes na zona urbana de Pelotas, RS, em 2014. Foi realizada analise descritiva dos dados e apresentada a prevalencia de quedas no ultimo ano. A analise de fatores demograficos, socioeconomicos, comportamentais e […]

SARCOPENIA IN BRAZILIAN RURAL AND URBAN ELDERLY WOMEN: IS THERE ANY DIFFERENCE?

OBJECTIVES There are many studies concerning sarcopenia prevalence from all over the world. However, to our knowledge, only two compared urban and rural sarcopenia and to date, none have been conducted in the Americas. The aim of this study was to evaluate the prevalence of sarcopenia in a convenience sample of women ≥60 y of age who underwent bone densitometry and live in urban and rural areas of southern Brazil. METHODS This was a cross-sectional study comprising 205 women ≥60 y of age who had undergone bone densitometry. Sarcopenia was defined according to the criteria recommended by the European Working Group on Sarcopenia in Older People. The diagnosis combined the evaluation of muscle mass (assessed by dual-energy x-ray absorptiometry), muscle strength (measured using a manual digital dynamometer), and muscular performance (evaluated by the 4-m walking speed test). Sociodemographic data, smoking status, chronic conditions, number of falls and fractures in the past year, and level of physical activity also were collected. RESULTS Sarcopenia was present in 2.4% of the total sample. Urban and rural populations significantly differed in terms of schooling (P < 0.001), occupation (P = 0.010), socioeconomic status (P = 0.001), and smoking status (P = 0.006). The environment in which the women lived was independently associated with sarcopenia (odds ratio, 9.561; 95% confidence interval, 1.021-89.523; P = 0.048). The prevalence of sarcopenia was significantly higher in the urban women than in the rural group (5.7 versus 0.7%, respectively; P = 0.047). After multivariate analysis, the environment of the womens residence remained independently associated with sarcopenia. CONCLUSION Urban elderly women are more vulnerable to sarcopenia than rural elderly women.

MON-PP178: Estimation of Body Fat in Adults Using a Portable a-mode Ultrasound

Rationale: Several paediatric nutrition risk screening tools have been developed yet no-one has demonstrated reproducibility and reliability outside of research. We explored nutrition screening in children attending the paediatric assessment unit, compared with standard anthropometric measures. Methods: Prospective study, n = 300 [median 3.15 yrs; SD ±4.97 yrs; 44.6% (n = 134) female; 25.7% (n = 77) 2). In the over 5 year olds 5.8% were thin [BMI-for-age (BAZ) 2).