The Prognostic Role of Phase Angle in Advanced Cancer Patients: A Systematic Review.

Phase angle (PA) is a ratio between the reactance and resistance obtained by bioelectric impedance analysis and has been interpreted as a cell membrane integrity indicator and a predictor of total body cell mass. A low PA may suggest deterioration of the cell membrane, which in advanced cancer patients may result in a reduced overall survival (OS). This systematic review sought to investigate the current evidence regarding whether there is an association between PA and OS in patients with advanced cancer (ie, metastatic disease). The search was conducted on electronic databases in August 2017. A total of 34 articles were identified in the initial literature search. Nine studies reporting on 1496 patients were deemed eligible according to our inclusion criteria. PA data were analyzed as continuous variables or according to different cutoffs, under a frequency of 50 Khz. Low PA was associated with worse nutrition status evaluated by body mass index, serum albumin level, transferrin, and fat-free mass. The median OS of the included papers varied from 25.5-330 days, and all studies analyzed showed a significant association between PA and OS, in that patients with low PA had worse OS. Future studies are necessary to justify the use of PA in therapeutic decisions for this population and to evaluate whether nutrition status can influence the association between PA and survival.

Accuracy of octa-polar bioelectrical impedance analysis for the assessment of total and appendicular body composition in children and adolescents with HIV: comparison with dual energy X-ray absorptiometry and air displacement plethysmography.

BACKGROUND: Body composition analysis has been used to investigate fat mass (FM) and bone mineral content (BMC) in children and adolescents diagnosed with HIV. Investigating the validity of bioelectrical impedance analysis (BIA) is interesting with respect to testing useful techniques for monitoring body composition in children and adolescents in clinical practice. The present study aimed to determine the validity of body composition analysis by BIA compared to dual-energy X-ray absorptiometry (DXA) and air displacement plethysmography (ADP) in children and adolescents an HIV diagnosis. METHODS: Sixty-four children and adolescents (35 females and 29 males) with a mean (SD) age of 12.22 (2.13) years and with an HIV diagnosis participated in the study. Fat-free mass (FFM), FM and body fat percentage (%BF) were obtained by BIA for comparison with DXA and ADP. Segmented FM (trunk, legs and arms), lean soft tissue mass (LSTM) (total and segmented) and BMC were obtained by BIA for comparison with DXA. RESULTS: BIA presented a clinically acceptable correlation with DXA and ADP for FFM. Values found by BIA were underestimated compared to ADP, and overestimated compared to DXA. BIA presented a clinically acceptable correlation with DXA for LSTM estimates (total and segmented parameters) in both sexes (underestimating FM and overestimating LSTM). For other components (%BF, FM and BMC), BIA had a clinically unacceptable correlation with the reference methods in both sexes. CONCLUSIONS: BIA was suitable for evaluating FFM and LSTM in children and adolescents with an HIV diagnosis. For FM, %BF and BMC, BIA was not suitable for performing an evaluation in both sexes.

Association between fat mass and bone mineral density among Brazilian women differs by menopausal status: The Pró-Saúde Study.

OBJECTIVE: The aim of this study was to investigate the association between bone mineral density (BMD) and fat mass (FM) in a multiethnic population of Brazilian women and to evaluate the influence of total body mass and lean mass on this association. METHODS: This was a cross-sectional study nested within the Pro-Saúde Study, a prospective cohort of university civil servants in Rio de Janeiro. Participants were pre- (n = 100) and postmenopausal (n = 166) women. Total fat, lean mass, and BMD of total body, lumbar spine, and femoral neck were measured using dual energy x-ray absorptiometry. The association of BMD with FM was investigated after adjustment for total body mass (model 1) and lean mass (model 2) and potential confounding variables using multivariate linear regression models. RESULTS: In model 1, FM was inversely associated with BMD for total body (B = -0.010; P < 0.01) and for femoral neck (B = -0.009 P < 0.05) in premenopausal women. No association between FM and BMD was observed in postmenopausal women. Model 2 yielded direct associations between FM and BMD (total and specific sites; B = 0.003-0.008; P < 0.01) in postmenopausal women only. CONCLUSIONS: Independently of the adjustment used, the results of the present study suggest the absence of an inverse association between FM and BMD in postmenopausal women. Additionally, when adjusted for lean mass, a direct association between FM and bone mass can be observed, suggesting that for postmenopausal women being slightly obese does not confer excessive risk for bone loss and may even result in a bone density advantage.

Physical activity throughout adolescence and body composition at 18 years: 1993 Pelotas (Brazil) birth cohort study.

BACKGROUND: Adolescence is a period of accelerated development and increases in body composition. Physical activity (PA) practice has been associated with the development of major components of body composition (bone, muscle and fat). However, the longitudinal effects of PA of different intensities during adolescence are still not well understood. Thus, the main goal this study has investigate the association between practice of moderate- and vigorous-intensity physical activity throughout adolescence and body composition, specifically lean mass (LM) and fat mass (FM), at age 18. METHODS: In this cohort study, physical activity was measured at 11, 15 and 18 years, using questionnaires. Thresholds of 300, 150 and 75 min per week, were used for MVPA, moderate- and vigorous-intensity physical activity, respectively. Consistent physical activity was defined as reaching the thresholds at the three follow-ups. FM and LM at age 18 were assessed by DXA and expressed as fat mass (FMI) and lean mass (LMI) indexes. To verify the association between the trajectories of MVPA, moderate- and vigorous-intensity physical activity in adolescence and FM and LM at 18, multivariate analyses were performed through multiple linear regressions adjusted for co-variables. RESULTS: A total of 3,176 adolescents were evaluated. The consistent practice of moderate- and vigorous-intensity physical activity according to thresholds during adolescence were directly related to the LMI in boys (moderate-intensity - ß = 0.40 and CI95 % 0.13; 0.68 and vigorous-intensity - ß = 0.95 and CI95 % 0.69; 1.21) and girls (Moderate-intensity - ß = 0.23 and CI95 % 0.02; 0.45 and vigorous-intensity - ß = 0.80 and CI95 % 0.29; 1.32). Practice of vigorous-intensity physical activity alone showed to be inversely associated with the FMI in boys (ß = -0.53 and CI95 % -0.96;-0.10). CONCLUSION: Consistent physical activity practice during adolescence was associated with greater lean mass in both sexes. In boys, vigorous-intensity physical activity was associated with less fat mass.

Effects of 12 weeks of combined training without caloric restriction on inflammatory markers in overweight girls.

The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13-17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6-10 repetitions at 60-70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50-80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (P < 0.01) and increase in fat-free mass (P < 0.01), VO2peak (P < 0.01), 1 RM for leg press (P < 0.01) and bench press (P < 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (P < 0.05) and leptin (P < 0.05), as well as in insulin resistance (P < 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls.

Bioelectrical impedance vector analysis in obese women before and after bariatric surgery: changes in body composition.

OBJECTIVE: Because of the inefficacy of standard methods for the evaluation of body composition of grade III obese individuals, it is difficult to analyze the quality of weight loss after bariatric surgery in these patients. Electrical bioimpedance vector analysis and the RXc graph uses crude resistance (R) and reactance (Xc) values, like components of the Z vector, to monitor variations in body fluid and the nutritional status of obese individuals. Using bioelectrical impedance vector analysis (BIVA) and the RXc graph, the objective of the present study was to evaluate long-term changes in weight and body composition of obese women after Roux-en-Y bariatric surgery. METHODS: A study was conducted on 43 grade III obese women submitted to bariatric surgery. Anthropometric and bioimpedance (800 mA-50 kHz) data were obtained during the preoperative period and 1, 2, 3, and 4 y after surgery. BIVA was performed by plotting resistance and reactance values corrected for body height (R/H and Xc/H, Ohm/m) as bivariates on the RXc graph. BIVA software was used to plot the vectors of the RXc plane. RESULTS: Surgery promoted changes in body composition, with a reduction of fat mass and of fat-free mass. During the postoperative period, the vectors demonstrated migration to the right lower quadrant of the graph, corresponding to the classification of cachexia and water retention. CONCLUSION: Weight loss due to surgery results in an important reduction of fat-free mass characterized by the position of most individuals in the cachexia quadrant throughout the postoperative period.

Aerobic plus resistance training was more effective in improving the visceral adiposity, metabolic profile and inflammatory markers than aerobic training in obese adolescents.

The purpose of this study was to determine whether aerobic plus resistance training (AT + RT) is more effective than aerobic training (AT) at reducing inflammatory markers and cardiovascular risk in obese adolescents. A total of 139 obese adolescents were enrolled, aged 15-19 years, body mass index (BMI) ≥ 95th percentile and participated in 1 year of interdisciplinary intervention. They were randomised into two groups: AT (n = 55), AT + RT (n = 61). Blood samples were collected to analyse glycaemia, insulin, the lipid profile, leptin and adiponectin concentrations. Insulin resistance was measured by homeostasis model assessment of insulin resistance index (HOMA-IR). The AT + RT group showed better results with regard to decreased body fat mass, low-density lipoprotein concentration (LDL-c) levels, subcutaneous and visceral fat and increased body lean mass. Indeed, a reduction of hyperleptinaemia and an increase in adiponectin concentrations, promoting an improvement in the leptin/adiponectin ratio, was observed. Important clinical parameters were improved in both types of exercise; however, AT + RT was more effective in improving the visceral adiposity, metabolic profile and inflammatory markers than AT alone, suggesting clinical applications for the control of intra-abdominal obesity and cardiovascular risk in the paediatric population.

The impact of nutritional supplementation on quality of life in patients infected with hepatitis C virus.

BACKGROUND: The present study aimed to evaluate the impact of animal and vegetable protein supplementation on health-related quality of life (HRQL) in patients with hepatitis C virus (HCV) and to investigate clinical and nutritional variables related to quality of life in these patients. METHODS: One hundred and forty patients infected with HCV were randomly assigned to one of two groups: the Soy Group (SG; n = 72), where patients received a soy supplement diet and the Casein Group (CG; n = 68), where patients received casein as a supplement. Anthropometric, biochemical and clinical assessments were performed in all patients, and the Short-Form Health Survey was applied at baseline and 12 weeks after study initiation. RESULTS: Before supplementation, poor HRQL scores were associated with female sex (P = 0.004) and advanced fibrosis (F3/F4; P = 0.04). Reduced HRQL scores were correlated with age (r = -0.263; P = 0.002), serum albumin levels (r = 0.245; P = 0.004), lean mass (r = 0.301; P < 0.0001) and body fat percentage (r = -0.262; P = 0.002). After 12 weeks of intervention, patients in both supplementation groups showed significantly increased HRQL scores, with no difference being observed between the SG and the CG. CONCLUSIONS: Nutritional therapy with either soybean or casein supplementation improved quality of life in patients infected with HCV. Quality of life was influenced by anthropometric, biochemical, clinical and sociodemographic factors in patients with HCV before nutritional supplementation.

Body composition in prepubertal, HIV-infected children: a comparison of bioelectrical impedance analysis and dual-energy X-ray absorptiometry.

BACKGROUND: The aim of this study was to compare bioelectrical impedance analysis (BIA) equations developed for healthy pediatric populations and for HIV-infected children using dual-energy X-ray absorptiometry (DXA) as the gold standard. MATERIALS AND METHODS: A cross-sectional study was carried out with 40 prepubertal, HIV-infected children who regularly attended the Pediatric Infectious Disease Clinic at the Universidade Federal de São Paulo, São Paulo, Brazil. The study was conducted from August to November 2008. Demographic data, clinical parameters, immunological status, and use of antiretroviral therapy were obtained from the patients' medical records. We performed anthropometric parameters and body composition analyses, analyzed body composition by BIA and DXA, and compared the results obtained from BIA through using equations for both healthy and HIV-infected populations. RESULTS: The mean ± SD age of the study population was 9.8 ± 1.2 years. Half of the population were females, and 82.5% of the children were clinically classified as B and C. Total body fat, by both absolute mass and by percentage, exhibited high homogeneity between the results obtained from BIA and DXA. However, there was no concordance in fat-free mass. The equation for healthy children showed good sensitivity and specificity when comparing the percentage of total body fat measured by DXA. CONCLUSION: BIA provides reliable data on total body fat but not fat-free mass when compared with DXA. The BIA equation developed for healthy pediatric populations can be used to determine total body fat in HIV-infected children.

Effects of pregnancy and feeding level on carcass and meat quality traits of Nellore cows.

Carcass and meat quality traits of 16 pregnant and 5 non-pregnant cows fed at 1.2 times maintenance and 16 pregnant and 6 non-pregnant fed ad libitum were evaluated. Pregnancy did not affect final body weight (FBW; P=0.0923), cold carcass yield (CCY; P=0.0513), longissimus muscle area (LMA; P=0.8260), rib fat thickness (RFT; P=0.1873) and shear force (WBSF; P=0.9707). A lower FBW (P=0.0028), LMA (P=0.0048) and RFT (P=0.0001) were observed in feed restricted cows. However, no differences were found for CCY (P=0.7243) and WBSF (P=0.0759) among feeding level groups. These data suggests that carcass and meat quality traits are not affected by pregnancy status in Nellore cows. Moreover, although cows experiencing feed restriction did have reduced deposition of subcutaneous fat and lean tissue, there were no major impacts on meat quality traits.

Is a body mass index of 23 kg/m² a reliable marker of protein-energy wasting in hemodialysis patients?

OBJECTIVE: To evaluate the body composition and inflammatory status in patients on hemodialysis (HD) according to the cutoff of 23 kg/m² for the body mass index (BMI). METHODS: Forty-seven patients (30 men, 11 diabetics, 53.8 ± 12.2 y of age, 58.2 ± 50.9 mo on HD) were studied. Anthropometric data and handgrip strength were evaluated. C-reactive protein, tumor necrosis factor-α, leptin, and interleukin-6 were measured. Mortality was assessed after 24 mo of follow-up. RESULTS: Nineteen patients (40.4%) presented BMI values lower than 23 kg/m² and leptin levels, midarm muscle area, and free-fat mass were significantly lower in these patients. The prevalence of functional muscle loss according to handgrip strength was not different between the BMI groups. The sum of skinfold thicknesses, the percentage of body fat, fat mass, the fat mass/free-fat mass ratio, and waist circumference were significantly lower in patients with a BMI lower than 23 kg/m², but the mean values did not indicate energy wasting. Patients with a BMI higher than 23 kg/m² presented a higher prevalence of inflammation and higher waist circumference and body fat values. The adiposity parameters were correlated with C-reactive protein and leptin. A Cox multivariate regression analysis demonstrated that C-reactive protein, tumor necrosis factor-α, and interleukin-6 predict cardiovascular mortality. CONCLUSION: Patients on HD with a BMI lower than 23 kg/m² did not present signs of energy wasting, whereas those with a BMI higher than 23 kg/m² had more inflammation, probably because of a greater adiposity. Thus, the BMI value of 23 kg/m² does not seem to be a reliable marker of protein-energy wasting in patients on HD.

Long-term leucine supplementation reduces fat mass gain without changing body protein status of aging rats.

OBJECTIVE: Aging is characterized by alterations in body composition such as an increase in body fat and decreases in muscle mass (sarcopenia) and bone density (osteopenia). Leucine supplementation has been shown to acutely stimulate protein synthesis and to decrease body fat. However, the long-term effect of consistent leucine supplementation is not well defined. This study investigated the effect of leucine supplementation during aging. METHODS: Six-month-old rats were divided into three groups: an adult group (n = 10) euthanized at 6 mo of age, a leucine group (n = 16) that received a diet supplemented with 4% leucine for 40 wk, and a control group (n = 19) that received the control diet for 40 wk. The following parameters were evaluated: body weight, food intake, chemical carcass composition, indicators of acquired chronic diseases, and indicators of protein nutritional status. RESULTS: Body weight and fat were lower in the leucine group after 40 wk of supplementation compared with the control group but still higher than in the adult group. The lipid and glycemic profiles were equally altered in the control and leucine groups because of aging. In addition, leucine supplementation did not affect the changes in protein status parameters associated with aging, such as decreases in body and muscle protein and total serum protein. CONCLUSION: The results indicate that leucine supplementation attenuates body fat gain during aging but does not affect risk indicators of acquired chronic diseases. Furthermore, supplemented animals did not show signs of a prevention of the decrease in lean mass associated with aging.