Bioelectrical Impedance Measurements Research Articles

Measures of Body Size and Composition and Risk of Incident Atrial Fibrillation in Older People: The Cardiovascular Health Study.

Various anthropometric measures, including height, have been associated with atrial fibrillation (AF). This raises questions about the appropriateness of using ratio measures such as body mass index (BMI), which contains height squared in its denominator, in the evaluation of AF risk. Among older adults, the optimal anthropometric approach to risk stratification of AF remains uncertain. Anthropometric and bioelectrical impedance measures were obtained from 4,276 participants (mean age = 72.4 years) free of cardiovascular disease in the Cardiovascular Health Study. During follow-up (1989-2008), 1,050 cases of AF occurred. BMI showed a U-shaped association, whereas height, weight, waist circumference, hip circumference, fat mass, and fat-free mass were linearly related to incident AF. The strongest adjusted association occurred for height (per each 1-standard-deviation increment, hazard ratio = 1.38, 95% confidence interval: 1.25, 1.51), which exceeded all other measures, including weight (hazard ratio = 1.21, 95% confidence interval: 1.13, 1.29). Combined assessment of log-transformed weight and height showed regression coefficients that departed from the 1 to -2 ratio inherent in BMI, indicating a loss of predictive information. Risk estimates for AF tended to be stronger for hip circumference than for waist circumference and for fat-free mass than for fat mass, which was explained largely by height. These findings highlight the prominent role of body size and the inadequacy of BMI as determinants of AF in older adults.

Arterial Stiffness and Cardiovascular Hemodynamics After Life-Long Endurance and Resistance Training in Aged Athletes

Despite the established health benefits of exercise, it is presently unknown whether a life-long endurance or resistance training regimen exhibits greater benefits on arterial stiffness and cardiovascular hemodynamics in aged athletes. PURPOSE: To compare the effects of life-long endurance and resistance training on arterial stiffness and cardiovascular hemodynamics in aged athletes. METHODS: Twenty-four endurance (END) and twenty resistance (RES) trained elderly athletes, with nine age-matched sedentary controls (CON), underwent resting pulse wave velocity and thoracic electrical bio-impedance measurements to assess arterial stiffness and cardiovascular hemodynamics, respectively. Participants were life-long athletes actively participating in masters athletic competitions. Participant characteristics were as follows (mean±SD): END 71±7 yrs, 174±5 cm, 72±8 kg, and 44.9±9.7 training years; RES 70±8 yrs, 173±7 cm, 84±13 kg, and 32.4±20.1 training years; CON 74±5 yrs, 171±5 cm, 80±11 kg, and 0±0 training years. Kruskal-Wallis test with Tukey’s post hoc analysis were used to assess differences between groups. RESULTS: Pulse wave velocity was lower in END and RES vs. CON (8.5±1.1 and 8.4±2.0 vs. 10.7±1.9 m/s; p<0.05). Cardiac index, stroke volume and index, ejection phase contractility index, inotropic state index and left stroke work index were higher, while stroke systemic vascular resistance index was lower in END vs. RES and CON (p<0.05). Central diastolic blood pressure was also lower in END vs. RES and CON (77±10 vs. 84±7 and 84±8 mmHg; p<0.05). Central systolic blood pressure, mean arterial pressure, and heart rate variability parameters were not different between groups (p≥0.05). CONCLUSIONS: While both training regimens exhibited lower arterial stiffness, aged athletes with a training history in endurance sports also demonstrated improved cardiovascular hemodynamics compared to their resistance sports counterparts and sedentary controls, revealing favourable influences on cardiovascular health. Although important musculoskeletal benefits are closely linked to aging and resistance training, our findings further indicate that resistance training may not protect the cardiovascular system to the same extent as life-long endurance training.

Oxygen desaturation in 6-min walk test is a risk factor for adverse outcomes in COPD.

The 6-min walk test (6MWT) is an exercise test that measures functional status in chronic obstructive pulmonary disease (COPD) patients and provides information on oxygen desaturation. We investigated oxygen desaturation during 6MWT as a risk factor for important COPD outcomes: mortality, frequency of exacerbations, decline in lung function and decline in lean body mass.433 COPD patients were included in the Bergen COPD Cohort Study 2006-2009, and followed-up for 3 years. Patients were characterised using spirometry, bioelectrical impedance measurements, Charlson comorbidity score, exacerbation history, smoking and arterial blood gases. 370 patients completed the 6MWT at the baseline of the study. Information on all-cause mortality was collected in 2011.Patients who experienced oxygen desaturation during the 6MWT had an approximately twofold increased risk of death (hazard ratio 2.4, 95% CI 1.2-5.1), a 50% increased risk for experiencing later COPD exacerbations (incidence rate ratio 1.6, 95% CI 1.1-2.2), double the yearly rate of decline in both forced vital capacity and forced expiratory volume in 1 s (3.2% and 1.7% versus 1.7% and 0.9%, respectively) and manifold increased yearly rate of loss of lean body mass (0.18 kg·m(-2) versus 0.03 kg·m(-2) among those who did not desaturate).Desaturating COPD patients had a significantly worse prognosis than non-desaturating COPD patients, for multiple important disease outcomes.

Assessment of storage shelf life of European squid (cephalopod: Loliginidae, Loligo vulgaris) by bioelectrical impedance measurements

The aim of this study was to examine the possibility of storage shelf life assessment of refrigerated squid Loligo vulgaris by bioelectrical impedance measurements.Fresh squid samples were kept in the refrigerator at 4 ± 1 °C during the period of 15 days and were examined every two days, starting on the 4th day post-mortem. The Agilent 4294A Precision Impedance Analyzer with needle-type multi electrode array arranged in bipolar configuration was used to measure impedance magnitude (|Z|) and phase (φ) at 200 frequencies from 100 Hz to 100 MHz. Protein solubility, color parameters and textural parameters have also been determined.Results showed that impedance (phase), color (a*) and protein solubility were highly correlated with the duration of storage, while texture parameters showed only moderate correlation. The correlation between phase and protein solubility was moderate until phase and texture parameters showed no correlation. The phase (φ) measured at 1 MHz showed a potential for the assessment of storage shelf life of the refrigerated European squid by grouping the samples into 3 distinctive groups post rigor mortis.

Bioelectrical Impedance Analysis at Popliteal Regions of Human Body using BIMS

Bioelectrical impedance (BI) at popliteal regions was measured using a bioelectrical impedance measurement system (BIMS), which employs the multi-frequency and the two-electrode method. Experiments were performed as follows. First, a constant AC current of 800 μA was applied to the popliteal regions (left and right) and the BI was measured at eight different frequencies from 10 to 500 kHz. When the applied frequency greater than 50 kHz was applied to human’s popliteal regions, the BI was decreased significantly. Logarithmic plot of impedance vs. frequency indicated two different mechanisms in the impedance phenomena before and after 50 kHz. Second, the relationship between resistance and reactance was obtained with respect to the applied frequency using BI (resistance and reactance) acquired from the popliteal regions. The phase angle (PA) was found to be strongly dependent on frequency. At 50 kHz, the PA at the right popliteal region was 7.8o slightly larger than 7.6o at the left popliteal region. Third, BI values of extracellular fluid (ECF)and intracellular fluid (ICF) were calculated using BIMS. At 10 kHz, the BI values of ECF at the left and right popliteal regions were 1664.14 Ω and 1614.08 Ω, respectively. The BI values of ECF and ICF decreased sharply in the frequency range of 10 to 50 kHz, and gradually decreased up to 500 kHz. Logarithmic plot of BI vs. frequency shows that the BI of ICF decreased noticeably at high frequency above 300 kHz because of a large decrease in the capacitance of the cell membrane.

A method to detect heart rate based on electrical bio-impedance

As a basic health indicator, heart rate has been widely used in clinical measurement and daily health care. Electrical bio-impedance (EBI) measurement provides non-invasive method for heart rate detection. Therefore, this paper proposed a method to detect heart rate based on EBI. With the BIOPAC EBI module, the signal can be de-noised in real-time. Finally, the de-noised EBI signal is used to compute heart rate. Four electrodes are located at radial artery of left upper limb in this method. The result proves that this method has high accuracy on heart rate measurement.

Rapid on-line non-destructive detection of the moisture content of corn ear by bioelectrical impedance spectroscopy

Moisture content of corn directly affects its quality and storage time, and the rapid on-line detection of the moisture content of corn ears not threshed or in vivo in the fields is required. Because of the special shape of corn ear, the rapid, low cost and non-destructive bioelectrical impedance measurement is more suitable for its moisture content detection. Using the four-electrode method with the Agilent E4980A precision LCR meter, the electrical impedance spectroscopies of the sweet corn ears and waxy corn ears at different moisture contents were acquired. The frequency range of the detection was from 20 Hz to 2 MHz and to enhance the contact, the attached-type electrodes were wrapped in cotton soaked with 0.1% NaCl solution. The impedance data over the frequency range from 300 Hz to 5 kHz were used to obtain the parameters of the bio-impedance Cole-Cole model. The results showed a good linear correlation (coefficient of determination R2=0.960) between the equivalent parallel resistance R∞ of sweet corn ear and the moisture content value determined by standard chemical method. The research proved that the bioelectrical impedance spectroscopy can be used for detecting the moisture content of corn ear. Keywords: moisture content, non-destructive detection, bioelectrical impedance spectroscopy, corn ear DOI: 10.3965/j.ijabe.20150806.1238 Citation: Zhao P F, Zhang H L, Zhao D J, Wang Z J, Fan L F, Huang L, et al. Rapid on-line non-destructive detection of the moisture content of corn ear by bioelectrical impedance spectroscopy. Int J Agric & Biol Eng, 2015; 8(6): 37－45.

Effect of Intravenous Infusion Solutions on Bioelectrical Impedance Spectroscopy.

Bioelectrical impedance (BIA) is often used to measure body fluid spaces and thereby body composition. However, in acute animal studies, we found that impedance was driven by the saline content of intravenous (IV) fluids and not by the volume. The aim of the study was to investigate the effect of 3 different fluids acutely administered on the change in impedance, specifically resistance (R). Nine healthy adults participated in 3 treatment (0.9% saline, 5% dextrose, and a mixture of 0.3% saline + 3.3% dextrose) experiments on nonconsecutive days. They all received 1 L of one of the treatments intravenously over a 1-hour period. Repeated BIA measurements were performed prior to IV infusion and then every 5 minutes for the 1-hour infusion period, plus 3 more measurements up to 15 minutes after the completion of the infusion. The change in R in the 0.9% saline infusion experiment was significantly lower than that of the glucose and mixture treatment ( P < .001). Bioelectrical impedance spectroscopy and BIA measure salt rather than the volume changes over the infusion period. Hence, in patients receiving IV fluids, BIA of any kind (single frequency or multifrequency) cannot be used to measure body fluid spaces or body composition.

Determinants of Anemia and Hemoglobin Concentration in Haitian School-Aged Children.

Anemia diminishes oxygen transport in the body, resulting in potentially irreversible growth and developmental consequences for children. Limited evidence for determinants of anemia exists for school-aged children. We conducted a cluster randomized controlled trial in Haiti from 2012 to 2013 to test the efficacy of a fortified school snack. Children (N = 1,047) aged 3-13 years were followed longitudinally at three time points for hemoglobin (Hb) concentrations, anthropometry, and bioelectrical impedance measures. Dietary intakes, infectious disease morbidities, and socioeconomic and demographic factors were collected at baseline and endline. Longitudinal regression modeling with generalized least squares and logit models with random effects identified anemia risk factors beyond the intervention effect. At baseline, 70.6% of children were anemic and 2.6% were severely anemic. Stunting increased the odds of developing anemia (adjusted odds ratio [OR]: 1.48, 95% confidence interval [CI]: 1.05-2.08) and severe anemia (adjusted OR: 2.47, 95% CI: 1.30-4.71). Parent-reported vitamin A supplementation and deworming were positively associated with Hb concentrations, whereas fever and poultry ownership showed a negative relationship with Hb concentration and increased odds of severe anemia, respectively. Further research should explore the full spectrum of anemia etiologies in school children, including genetic causes.

Intake of ruminant trans-fatty acids, assessed by diet history interview, and changes in measured body size, shape and composition.

Studies have suggested that total intake of trans-fatty acids (TFA) is positively associated with changes in body weight and waist circumference, whereas intake of TFA from ruminant dairy and meat products (R-TFA) has not been associated with weight gain. However, these previous studies are limited by self-reported measures of body weight and waist circumference or by a cross-sectional design. The objective of the present study was to investigate if R-TFA intake was associated with subsequent changes in anthropometry (body weight, waist and hip circumference) measured by technicians and body composition (body fat percentage). A 6-year follow-up study. Information on dietary intake was collected through diet history interviews, and anthropometric and bioelectrical impedance measurements were obtained by trained technicians at baseline (1987-1988) and at follow-up (1993-1994). Multiple regression with cubic spline modelling was used to analyse the data. Copenhagen County, Denmark. Two hundred and sixty-seven men and women aged 35-65 years from the Danish MONICA (MONItoring of trends and determinants in CArdiovascular diseases) cohort. The median R-TFA intake was 1.3 g/d (5th, 95th percentile: 0.4, 2.7 g/d) or 0.6% of the total energy intake (5th, 95th percentile: 0.2, 1.1%). No significant associations were observed between R-TFA intake and changes in body weight, waist and hip circumference or body fat percentage. R-TFA intake within the range present in the Danish population was not significantly associated with subsequent changes in body size, shape or composition and the 95% confidence intervals indicate that any relevant associations are unlikely to have produced these observations.

Body Composition, Physical Activity And Physical Function Outcomes 12 To 24 Months After Bariatric Surgery.

Physical activity post bariatric surgery is associated with greater weight loss outcomes. However, long-term data on patients’ physical activity and physical function levels are currently scarce. PURPOSE: To examine associations between body composition, physical activity, and physical function among obese adults 12–24 months post bariatric surgery. METHODS: Baseline data from patients recruited into an ongoing exercise intervention were analysed. Body composition was assessed using bioelectrical impedance, and waist and hip circumference measurements. Physical activity was estimated using a triaxial accelerometer worn at the waist for 7 days, and physical function was assessed by an incremental shuttle walk test (ISWT), grip strength, and a sit to stand test (STS). Results are presented as mean ± SD. RESULTS: A total of 22 patients with a mean age of 48.1 ± 9.19 years and BMI of 39 ± 5.1kg·m2 were recruited. Mean daily moderate to vigorous physical activity was 33 ± 19.3 min. Grip strength (right: 27.2 ± 8.5 kg; left: 26.8 ± 9.8 kg) was positively correlated with body mass (right: r = 0.621, p = 0.002; left: r = 0.540, p = 0.009) and fat free mass (right: r = 0.838, p < 0.001; left: r = 0.768, p < 0.001) but not fat mass. ISWT (325.9 ± 90.4 cm) was negatively correlated with fat mass (r = -0.520, p = 0.013), hip (r = 0.-486, p = 0.022) and waist (r = -0.521, p = 0.013) circumferences, and the STS test (13.2 ± 5.4 s) was positively correlated with waist circumference (r = 0.422, p = 0.05) but not fat free mass. When sub-divided by median split into high and low performers, the ISWT displayed a significant difference between groups in fat mass (t (20) -2.829, p = 0.010): high performers had a lower fat mass (42.0 ± 6.5 kg) than low performers (53.1 ± 10.9 kg). A significant difference was also observed between low and high performers in the STS test (t (11.5) 2.276, p = 0.043): high performers had a greater fat free mass (63.9 ± 12.5 kg) than low performers (54.3 ± 5.1 kg). CONCLUSION: Higher physical function was associated with favourable body composition assessments 12–24 months after obesity surgery. The role of post-operative physical activity in contributing to body composition and physical function warrants further attention.

Bioimpedance vector analysis as a tool for the determination and adjustment of dry weight in patients undergoing hemodialysis

Overhydration in hemodialysis patients is associated with cardiovascular mortality. Adequate removal of liquids and achievement of dry weight is one of the main goals of therapy. So far there are no clinical or laboratory parameters that are reliable, simple and affordable for its determination. The bioelectrical impedance vector analysis (BIVE) is a tool that allows identifying and monitoring hydration status, so the aim of this study was to use BIVE to adjust the intensity of ultrafiltration and achieve dry weight in hemodialysis patients. We studied 26 patients on hemodialysis, which were performed monthly measurements of bioelectrical impedance for four months. Corresponding vectors were plotted to know in an individual way the state of hydration, according to which the dry weight was adjusted when necessary. Dry weight adjustment was performed in 13 patients, 7 of which required increase and 6 decrease of dry weight. The displacement of vectors on the ellipses corresponded to the type of intervention made. Dry weight was reached in 84.6% of patients at the end of the study with a significant decrease in mean arterial blood pressure and an increase in phase angle in the group of decrease of dry weight. Bioelectrical impedance vector analysis is an useful tool for adjusting the dry weight in patients undergoing hemodialysis.

Persistent Low Grade Inflammation is linked to Metabolic Dysfunction in HIV‐positive South African Females

Protease inhibitors (PIs) is linked to adverse metabolic/anthropometric derangements, increasing the risk for cardiovascular diseases (CVD) onset in HIV‐infected individuals. As limited information is available regarding such PI‐mediated effects in the South African context, this cross‐sectional study evaluated an HIV‐positive female population (20‐40 years) in the Cape Winelands Health District. Participants were classed into: a) HIV‐negative, b) HAART‐naïve, and c) PI‐treated groups that underwent basic anthropometrical evaluations (weight, height, body mass index [BMI], hip circumference, waist circumference), and bioelectrical impedance measurements (fat mass, visceral adipose tissue and subcutaneous adipose tissue). An assessment of circulating biomarkers for inflammation (C‐reactive protein [CRP]) and metabolic dysfunction (leptin) was also completed. These data reveal that females from all three groups displayed elevated waist‐to‐hip ratios, with those on PI treatment exhibiting increased vs. matched controls. Moreover, HIV‐positive individuals displayed strong positive correlations between CRP and leptin (r=0.71) and leptin and BMI (r=0.85; p&lt;0.05), and moderate positive correlations between leptin and total fat (r=0.61), CRP and total fat (r=0.49), as well as CRP and BMI (r=0.67). Our data show that persistent low grade inflammation is strongly linked to metabolic dysfunction and obesity in relatively young HIV‐positive South African females. Such changes therefore place female HIV‐positive individuals at increased risk for the future development of CVD that will require an integrated clinical strategy to help counter this growing threat.

Ready-to-Use Supplementary Food Increases Fat Mass and BMI in Haitian School-Aged Children1–3

Background: In Haiti and other countries, large-scale investments in school feeding programs have been made with marginal evidence of nutrition outcomes.Objective: We aimed to examine the effectiveness of a fortified ready-to-use supplementary food (RUSF), Mamba, on reduced anemia and improved body composition in school-aged children compared to an unfortified cereal bar, Tablet Yo, and control groups.Methods: A cluster, randomized trial with children ages 3–13 y (n = 1167) was conducted in the north of Haiti. Six schools were matched and randomized to the control group, Tablet Yo group (42 g, 165 kcal), or Mamba group (50 g, 260 kcal, and >75% of the RDA for critical micronutrients). Children in the supplementation groups received the snack daily for 100 d, and all were followed longitudinally for hemoglobin concentrations, anthropometry, and bioelectrical impedance measures: baseline (December 2012), midline (March 2013), and endline (June 2013). Parent surveys were conducted at baseline and endline to examine secondary outcomes of morbidities and dietary intakes. Longitudinal regression modeling using generalized least squares and logit with random effects tested the main effects.Results: At baseline,14.0% of children were stunted, 14.5% underweight, 9.1% thin, and 73% anemic. Fat mass percentage (mean ± SD) was 8.1% ± 4.3% for boys and 12.5% ± 4.4% for girls. In longitudinal modeling, Mamba supplementation increased body mass index z score (regression coefficient ± SEE) 0.25 ± 0.06, fat mass 0.45 ± 0.14 kg, and percentage fat mass 1.28% ± 0.27% compared with control at each time point (P < 0.001). Among boys, Mamba increased fat mass (regression coefficient ± SEE) 0.73 ± 0.19 kg and fat-free mass 0.62 ± 0.34 kg compared with control (P < 0.001). Mamba reduced the odds of developing anemia by 28% compared to control (adjusted OR: 0.72; 95% CI: 0.57, 0.91; P < 0.001). No treatment effect was found for hemoglobin concentration.Conclusion: To our knowledge, this is the first study to give evidence of body composition effects from an RUSF in school-aged children.

Mo1102 Bioelectric Impedance and Anthropometric Measurements in Patients With GERD

Mo1102 Bioelectric Impedance and Anthropometric Measurements in Patients With GERD

Vitamin D, vitamin D binding protein, and longitudinal outcomes in COPD.

BackgroundAssociations between Vitamin D3 [25(OH)D], vitamin D binding protein (VDBP) and chronic obstructive pulmonary disease (COPD) are previously reported. We aimed to further investigate these associations on longitudinal outcomes.Methods426 COPD patients from western Norway, GOLD stage II-IV, aged 40–76, were followed every six-month from 2006 through 2009 with spirometry, bioelectrical impedance measurements and registration of exacerbation frequency. Serum 25(OH)D and VDBP levels were determined at study-entry by high-performance liquid chromatography coupled with mass spectrometry and enzyme immunoassays respectively. Yearly change in lung function and body composition was assessed by generalized estimating equations (GEE), yearly exacerbation rate by negative binomial regression models, and 5 years all-cause mortality by Cox proportional-hazard regression.Results1/3 of the patients had vitamin D deficiency (<20ng/mL) and a greater decline in both FEV1 and FVC, compared to patients with normal levels; for FEV1 this difference only reached statistical significance in the 28 patients with the lowest levels (<10ng/mL, p = 0.01). Neither 25(OH)D nor VDBP levels predicted exacerbation rate, change in fat free mass index or risk of death.ConclusionSevere vitamin D deficiency may affect decline in lung function parameters in COPD. Neither 25(OH)D nor VDBP levels did otherwise predict markers of disease progression.

Bioelectrical impedance outperforms waist circumference for predicting cardiometabolic risk in Congolese hypertensive subjects: a cross-sectional study.

BackgroundWaist circumference threshold values used in sub-Saharan Africa correspond to those of European populations and are therefore inappropriate. Thus, they may over predict insulin resistance, especially in hypertensive Africans, in whom there is often no association between blood pressure and insulin resistance. Using bioelectrical impedance measurement in sub-Saharan Africa could possibly be advantageous to overcome the shortcomings of waist circumference measurement. The aim of this study was to evaluate the contribution of body composition estimation by bioelectrical impedance to predict cardiometabolic risk in Congolese hypertensive subjects.MethodsCardiovascular profiling and body composition analysis by bioelectrical impedance was measured in 400 patients (men = 40%; age = 51.1 ± 12.6 years). Patients were diagnosed with a metabolic syndrome (MS) according to the IDF Criteria with and without the “blood pressure” criterion to remove any confounding autocorrelation bias, a visceral fat-MS (with and without the “blood pressure” criterion) being defined by the presence of ≥ 2 criteria with the precondition of excess visceral fat defined by a bio impedance measurement score >10/30. Total cardiovascular risk was assessed using the criteria of Framingham-2008.ResultsThe frequencies of enlarged waist circumference (71.9% vs 68.9%, p = 0.52) and IDF-MS without blood pressure criterion (24.9% vs 21.9%, p = 0.48) were similar among hypertensive vs. non hypertensive however excess visceral fat (57.6% vs 33.8%, p <0.0001) as well as visceral fat-MS without blood pressure criterion (18.9% vs 11.3%, p = 0.04) were more prevalent among hypertensive. Finally, total cardiovascular risk as well as arterial hypertension risk were associated with visceral fat, but not with waist circumference (p > 0.05).ConclusionsPending the determination of thresholds values for pathological waist circumference adapted to sub-Saharan populations, using bioelectrical impedance measurement may contribute to better characterize the cardiometabolic risk and the insulin resistant phenotype of hypertensive sub-Saharan Africans.

Body composition in Nepalese children using isotope dilution: the production of ethnic-specific calibration equations and an exploration of methodological issues.

Background. Body composition is important as a marker of both current and future health. Bioelectrical impedance (BIA) is a simple and accurate method for estimating body composition, but requires population-specific calibration equations.Objectives. (1) To generate population specific calibration equations to predict lean mass (LM) from BIA in Nepalese children aged 7–9 years. (2) To explore methodological changes that may extend the range and improve accuracy.Methods. BIA measurements were obtained from 102 Nepalese children (52 girls) using the Tanita BC-418. Isotope dilution with deuterium oxide was used to measure total body water and to estimate LM. Prediction equations for estimating LM from BIA data were developed using linear regression, and estimates were compared with those obtained from the Tanita system. We assessed the effects of flexing the arms of children to extend the range of coverage towards lower weights. We also estimated potential error if the number of children included in the study was reduced.Findings. Prediction equations were generated, incorporating height, impedance index, weight and sex as predictors (R2 93%). The Tanita system tended to under-estimate LM, with a mean error of 2.2%, but extending up to 25.8%. Flexing the arms to 90° increased the lower weight range, but produced a small error that was not significant when applied to children <16 kg (p 0.42). Reducing the number of children increased the error at the tails of the weight distribution.Conclusions. Population-specific isotope calibration of BIA for Nepalese children has high accuracy. Arm position is important and can be used to extend the range of low weight covered. Smaller samples reduce resource requirements, but leads to large errors at the tails of the weight distribution.

Polymorphism G1359A of the cannabinoid receptor gene (CNR1): allelic frequencies and influence on cardiovascular risk factors in a multicentre study of Castilla-Leon.

A polymorphism (1359 G/A) of the CNR1 gene was reported as a common polymorphism in Caucasian populations and was related to cardiovascular risk factors. The present study aimed to investigate the allelic distribution of polymorphism (G1359A) of the CB1 receptor gene in a geographical area of Spain (Community of Castilla y Leon) and to evaluate the influence of this polymorphism on obesity anthropometric parameters and cardiovascular risk factors in the fasted state in obese patients. A population of 341 obese subjects was analysed. Tetrapolar electrical bioimpedance measurement, blood pressure measurement, a serial assessment of nutritional intake with 3days of written food records and a biochemical analysis were all performed. One hundred and seventy-seven patients (51.9%) had the genotype G1359G (wild-type group) and 164 (48.1%) patients were A carriers: G1359A (136 patients; 39.9%) or A1359A (28 patients; 8.2%) (mutant type group). The Health Area of Palencia had a lower frequency of wild-type genotype and G allelic frequency than all the other Health Areas. Segovia and Burgos Areas had a higher frequency of wild-type genotype and G allelic frequency than the other Health Areas. High-density lipoprotein (HDL) cholesterol was higher in the mutant type group and blood tryglicerides were lower in the same group. In conclusion, the novel finding of the present study is the association of the mutant type group G1359A and A1359A with a better lipid profile (triglycerides and HDL cholesterol) than the wild-type group. The frequencies of this polymorphism are different among Health Areas of Castilla y Leon (Spain).

Sarcopenia Is Associated with High Pulse Pressure in Older Women.

Introduction. Sarcopenia is a geriatric syndrome associated with impairment of muscle function, metabolism, and cognition in older women. Recent studies have shown a relationship between changes in muscle mass and the cardiovascular system. However, this relationship has not been fully elucidated. Methods. One hundred and thirty community-dwelling Brazilian older women (65.4 ± 6.3 years) were recruited to participate in this study. Data on body composition (via bioelectrical impedance measurements), cardiovascular parameters (using an automatic and noninvasive monitor), and muscle function (using a 3-meter gait speed test) were measured. Results. Sarcopenic older women (n = 43) presented higher levels of pulse pressure (PP) (60.3 ± 2.6 mmHg) and lower muscle function (0.5 ± 0.0 m/s) compared with nonsarcopenic subjects (n = 87) (53.7 ± 1.5 mmHg; 0.9 ± 0.0 m/s) (P < 0.05). Linear regression analysis demonstrated a significantly negative association between skeletal muscle index (SMI) and PP levels (β = −226, P < 0.05). Furthermore, sarcopenic older women showed a 3.1-fold increased risk of having higher PP levels compared with nonsarcopenic women (IC = 1.323–7.506) (P < 0.05). Conclusion. Sarcopenic older women showed lower muscle function and higher cardiovascular risk due to increased PP levels compared with nonsarcopenic subjects.