Showing papers on "Body water published in 2011"
TL;DR: FO defined by m-BIA is significantly correlated with markers of malnutrition, inflammation and atherosclerosis in PD patients, and correlated well with volume overload as assessed by echocardiography.
Abstract: Background Chronic fluid overload (FO) is frequently present in peritoneal dialysis (PD) patients and is associated with hypertension and left ventricular hypertrophy and dysfunction, which are important predictors of death in dialysis patients. In the present study, we investigated the relationship between nutrition, inflammation, atherosclerosis and body fluid volumes measured by multi-frequency bioimpedance analysis (m-BIA) in PD patients. In addition, we analysed the relationship of extracellular volume values by m-BIA to echocardiographic parameters in order to define its usefulness as a measure of FO. Methods Ninety-five prevalent PD patients (mean age 50 ± 13 years, 10 of them diabetic) were enrolled. Extracellular water (ECW), total body water (TBW), dry lean mass (DLM) and phase angle (PA) were measured by m-BIA. Volume status was determined by measuring left atrium diameter (LAD) and left ventricular end-diastolic diameter (LVEDD). Measurement of carotid artery intima-media thickness (CA-IMT) was used to assess the presence of subclinical atherosclerosis. Serum albumin was used as a nutritional marker, and serum C-reactive protein (CRP) was used as an inflammatory marker. Results Mean ECW/height was 10.0 ± 1.0 L/m for whole group and 9.3 ± 0.6 L/m in patients with normal clinical hydration parameters. In correlation analysis, markers of nutrition, inflammation and atherosclerosis correlated well with m-BIA parameters. When we used echographically measured LAD (> 40 mm) or LVEDD (> 55 mm) as a confirmatory parameter, a cut-off value of 10.48 L/m ECW/height (78% specificity, with a sensitivity of 77% for LAD and 72% specificity, with a sensitivity of 70% for LVEDD) was found in ROC analysis for the diagnosis of FO. Patients with FO were older and had higher systolic blood pressure, cardiothoracic index, serum CRP level and mean CA-IMT than patients without FO. Patients with inflammation had higher CA-IMT values. In multivariate analysis, only two factors-low urine output and ECW/height-were independently associated with the presence of inflammation. Conclusions FO defined by m-BIA is significantly correlated with markers of malnutrition, inflammation and atherosclerosis in PD patients. The indices obtained from m-BIA, especially ECW/height, correlated well with volume overload as assessed by echocardiography and might be a measure worth testing in a properly designed clinical study.
116 citations
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TL;DR: It is unclear whether the health benefits of water and fluid ingestion are a function of the process of frequent fluid intake or the maintenance of a potentially expanded state of hydration.
Abstract: Daily adequate water intake to maintain euhydration is arguably the most important nutrient requirement for humans. Within a margin of error, the body regulates the maintenance of body fluid balanc...
76 citations
TL;DR: BIA is more accurate at assessing nutritional status in this population than is the measurement of skinfold thickness and the newly developed TEE equation, which uses body composition, provides a reasonable estimate of energy expenditure in these children despite its variability.
67 citations
01 Jan 2011
TL;DR: In this paper, the authors describe the rate of absorption of water in the body water pool and the volume and rate of renewal of this pool and show that water appeared in plasma and blood cells within 5 min following ingestion and was entirely distributed in the water pool within ~75-120 min.
Abstract: This study describes the rate of absorption of water in the body water pool and the volume and rate of renewal of this pool. The experiment was conducted on 36 healthy male subjects (18-35 yo, 76.9 kg, BMI = 23.3 kg/m2) drinking ad libitum, with 2 L/day of natural mineral water in their beverages. Following ingestion of natural mineral water with deuterium oxide (D2O) as tracer, the deuterium to hydrogen ratio (D/H) was measured in blood over the following hour and in urine over the following 9 days. Pharmacokinetic analysis of D/H show that water appeared in plasma and blood cells within 5 min following ingestion and was entirely distributed in the body water pool within ~75-120 min. The volume of the body water pool was 46.6 L (60.7 % body mass) and its turnover (or water clearance, i.e., the volume added in the pool from water in food and drinks and metabolic water, and removed from the pool through urine, feces, sweat, perspiration, and respiration, was 4.58 L/day. The mean residence time of water in the body water pool was 10.3 days indicating that half of the pool (i.e., the half-life) was replaced in 7.2 days. Water ingested under the form of natural mineral waters, with a low mineral content, appears in plasma and blood cells in less than 5 min, and is distributed in the entire body water pool in less than 2 hours. In the young healthy male subjects studied who remained well hydrated by drinking 2 L of natural mineral water/day, the entire body water pool was completely renewed in ~50 days.
62 citations
TL;DR: It is proposed that total body energy equilibrium is maintained during treatment of hypothyroidism and that weight loss observed during such treatment is caused by excretion of excess body water associated with untreated myxoedema.
Abstract: Context: In hypothyroidism, resting energy expenditure (REE) is reduced and weight gain is common. Physical activity contributes to the total daily energy expenditure, and changes in physical activity might contribute to hypothyroid-associated weight changes. Objective: The objective of the present study was to evaluate mechanisms involved in body weight changes associated with hypothyroidism. Design, Setting, and Participants: We conducted a 1-yr controlled follow-up study on outpatients newly diagnosed with hypothyroidism (n = 12) and a euthyroid measurement control group (n = 10). Main Outcome and Interventions: Changes in body mass and composition (dual-energy x-ray analysis scan), REE (indirect calorimetry), and spontaneous physical activity (pedometers and two different questionnaires) were studied before and after 12 months of l-T4 therapy or observation (control group). Results: TSH changed from 102 (85) to 2.2 (2.1) mU/liter mean (SD) and free T4 from 4.5 (2.1) to 18 (3.3) pmol/liter after 1 yr o...
61 citations
01 Jan 2011
TL;DR: The concentrations of various electrolytes, pH, and water balance are determined by many interwoven systems to maintain homeostasis and any imbalance results in metabolic and respiratory acid–base disorders.
Abstract: The concentrations of various electrolytes, pH, and water balance are determined by many interwoven systems to maintain homeostasis. The composition and volume of extracellular fluid are regulated by complex hormonal and nervous system mechanisms that coordinate to control osmolality, volume, and pH. The osmolality of extracellular fluid is due mainly to Na + and accompanying anions. The kidneys are the major organs that regulate extracellular fluid composition and volume via their functional units known as nephrons. Kidneys regulate acid–base balance by excreting nonvolatile acids and conserving HCO 3 – . Lungs regulate volatile acid CO 2 excretion. These functions are coordinated and any imbalance results in metabolic and respiratory acid–base disorders. The acid–base disorders are assessed by measuring arterial blood gases and pH values, venous blood electrolyte concentrations, and serum and urinary anion gap values. These disorders often occur as complex conditions. Despite considerable variation in fluid intake, an individual maintains water balance and a constant composition of body fluids. The homeostatic regulation of water is also discussed in the chapter.
56 citations
TL;DR: The findings support the interpretation that the body primarily defends p[Na+] and not BM during exercise and that a reduction in BM can occur without an equivalent reduction in TBW during prolonged exercise and support that drinking without controlling for BM loss may allow athletes to complete these events.
Abstract: OBJECTIVE To measure changes in body mass (BM), total body water (TBW), fluid intake, and blood biochemistry in athletes during 21.1-km and 56-km foot races. DESIGN Observational study. SETTING 2009 Two Oceans Marathon, South Africa. PARTICIPANTS Twenty-one (21.1 km) and 12 (56 km) participants were advised to drink according to thirst or their own race drink plan (ad libitum). MAIN OUTCOME MEASURES Body mass, TBW, plasma osmolality, plasma sodium (p[Na]), and plasma total protein ([TP]) concentrations were measured before and after race. Fluid intake was recorded from recall after race. RESULTS Significant BM loss occurred in both races (21.1 km; -1.4 ± 0.6 kg; P < 0.000 and 56 km; -2.5 ± 1.1 kg; P < 0.000). Total body water was reduced in the 56-km race (-1.4 ± 1.1 kg; P < 0.001). A negative linear relationship was found between percentage change (%Δ) in TBW and %Δ in BM in the 56-km runners (r = 0.6; P < 0.01). Plasma osmolality and [TP] increased significantly in the 56-km runners (6.8 ± 8.2 mOsm/kg H2O; P < 0.05 and 5.4 ± 4.4 g/L; P < 0.01, respectively), but all other biochemical measures were within the normal range. CONCLUSIONS Although TBW decreased in the 56-km race and was maintained in the 21.1-km race, the change in TBW over both races was less than the BM, suggesting that not all BM lost during endurance exercise is a result purely of an equivalent reduction in TBW. These findings support the interpretation that the body primarily defends p[Na] and not BM during exercise and that a reduction in BM can occur without an equivalent reduction in TBW during prolonged exercise. Furthermore, these data support that drinking without controlling for BM loss may allow athletes to complete these events.
55 citations
TL;DR: Fuid administration in patients with septic shock produced a minimal increase in intrathoracic blood volume, and the percentage of volume retained in this space was not correlated with the interstitial/plasma volume ratio.
Abstract: Our objective was to study the response to a fluid load in patients with and without septic shock, the relationship between the response and baseline fluid distributions and the ratios of the various compartments A total of 18 patients with septic shock and 14 control patients without pathologies that increase capillary permeability were evaluated prospectively We used transpulmonary thermodilution to measure the extravascular lung water index, intrathoracic blood volume index and pulmonary blood volume For the measurement of the initial distribution volume of glucose, plasma volume and extracellular water we used dilutions of glucose, indocyanine green and sinistrin respectively Transpulmonary thermodilution and dilutions of glucose were repeated 75 minutes after the beginning of the fluid load The patients in the septic group had higher volumes of extracellular water (median 295 vs 234 ml/kg, P < 0001), lower intrathoracic blood volume index (median 894 vs 1157 ml/m2, P < 0003), higher pulmonary permeability ratios (extravascular lung water/pulmonary blood volume) (P < 0003) and higher systemic permeability ratios (interstitial/plasma volume) (P < 004) The intrathoracic blood volume index increase after fluid loading was lower in the septic group (10 vs 145 ml/m2) The pulmonary permeability ratios did not correlate with the systemic permeability ratios, and in the septic group, the percentage volume retained in the intrathoracic blood volumes after fluid loading did not correlate with the systemic permeability ratios Septic shock can cause a redistribution of fluids Fluid administration in these patients produced a minimal increase in intrathoracic blood volume, and the percentage of volume retained in this space was not correlated with the interstitial/plasma volume ratio
49 citations
TL;DR: Ingesting a low dose of creatine for 6 wk significantly increased plasma creatine concentration and enhanced resistance to fatigue during repeated bouts of high-intensity contractions.
48 citations
TL;DR: The use of ρ(N)(,5) as a new comparator allowing a clinician to incrementally monitor removal of extracellular fluid from patients over the course of dialysis treatments is established.
Abstract: Prescription of an appropriate dialysis target weight (dry weight) requires accurate evaluation of the degree of hydration. The aim of this study was to investigate whether a state of normal hydration (DWcBIS) as defined by calf bioimpedance spectroscopy (cBIS) and conventional whole body bioimpedance spectroscopy (wBIS) could be characterized in hemodialysis (HD) patients and normal subjects (NS). wBIS and cBIS were performed in 62 NS (33 m/29 f) and 30 HD patients (16 m/14 f) pre- and post-dialysis treatments to measure extracellular resistance and fluid volume (ECV) by the whole body and calf bioimpedance methods. Normalized calf resistivity (ρN,5) was defined as resistivity at 5 kHz divided by the body mass index. The ratio of wECV to total body water (wECV/TBW) was calculated. Measurements were made at baseline (BL) and at DWcBIS following the progressive reduction of post-HD weight over successive dialysis treatments until the curve of calf extracellular resistance is flattened (stabilization) and the ρN,5 was in the range of NS. Blood pressures were measured pre- and post-HD treatment. ρN,5 in males and females differed significantly in NS. In patients, ρN,5 notably increased with progressive decrease in body weight, and systolic blood pressure significantly decreased pre- and post-HD between BL and DWcBIS respectively. Although wECV/TBW decreased between BL and DWcBIS, the percentage of change in wECV/TBW was significantly less than that in ρN,5 (−5.21 ± 3.2% versus 28 ± 27%, p < 0.001). This establishes the use of ρN,5 as a new comparator allowing a clinician to incrementally monitor removal of extracellular fluid from patients over the course of dialysis treatments. The conventional whole body technique using wECV/TBW was less sensitive than the use of ρN,5 to measure differences in body hydration between BL and DWcBIS.
47 citations
TL;DR: The finding that TBW was protected by ad libitum drinking despite ∼2% body mass loss suggests that the concept of ‘voluntary dehydration’ may require revision, and the extent to which humans need to replace fluid losses during exercise remains contentious.
Abstract: The extent to which humans need to replace fluid losses during exercise remains contentious despite years of focused research. The primary objective was to evaluate ad libitum drinking on hydration status to determine whether body mass loss can be used as an accurate surrogate for changes in total body water (TBW) during exercise. Data were collected during a 14.6-km route march (wet bulb globe temperature of 14.1°C ). 18 subjects with an average age of 26 ± 2.5 (SD) years participated. Their mean ad libitum total fluid intake was 2.1 ± 1.4 litres during the exercise. Predicted sweat rate was 1.289 ± 0.530 l/h. There were no significant changes (p>0.05) in TBW, urine specific gravity or urine osmolality despite an average body mass loss (p<0.05) of 1.3 ± 0.45 kg during the march. Core temperature rose as a function of marching speed and was unrelated to the % change in body mass. This suggests that changes in mass do not accurately predict changes in TBW (r=-0.16) because either the body mass loss during exercise includes losses other than water or there is an endogenous body water source that is released during exercise not requiring replacement during exercise, or both. Ad libitum water replacement between 65% and 70% of sweat losses maintained safe levels of hydration during the experiment. The finding that TBW was protected by ad libitum drinking despite approximately 2% body mass loss suggests that the concept of 'voluntary dehydration' may require revision.
TL;DR: This study provides the first validation of the D(2) O dilution method for the minimally-invasive, accurate, repeatable and objective measurement of body water and fat in living equids.
Abstract: REASONS FOR PERFORMING THE STUDY: Excessive accumulations or depletions of body fat have been associated with increased morbidity and mortality in horses and ponies. An objective, minimally-invasive method to accurately quantify body fat in living animals is required to aid nutritional management and define welfare/performance limits. OBJECTIVES: To compare deuterium oxide (D(2) O) dilution-derived estimates of total body water (TBW) and body fat with values obtained by 'gold standard' proximate analysis and cadaver dissection. HYPOTHESIS: D(2) O dilution offers a valid method for the determination of TBW and body fat in equids. METHODS: Seven mature (mean ± s.e. 13 ± 3 years, 212 ± 14 kg, body condition scores 1.25-7/9), healthy, Welsh Mountain pony mares, destined for euthanasia (for nonresearch purposes) were used. Blood samples were collected before and 4 h after D(2) O (0.11-0.13 g/kg bwt, 99.8 atom percent excess) administration. Plasma was analysed by gas isotope ratio mass spectrometry following filtration and zinc reduction. After euthanasia, white adipose tissue (WAT) mass was recorded before all body tissues were analysed by proximate chemical analyses. RESULTS: D(2) O-derived estimates of TBW and body fat were strongly associated with proximate analysis- and dissection-derived values (all r(2) >0.97, P≤0.0001). Bland-Altman analyses demonstrated good agreements between methods. D(2) O dilution slightly overestimated TBW (0.79%, limits of agreement (LoA) -3.75-2.17%) and underestimated total body lipid (1.78%, LoA -0.59-4.15%) and dissected WAT (0.72%, LoA -2.77-4.21%). CONCLUSIONS AND POTENTIAL RELEVANCE: This study provides the first validation of the D(2) O dilution method for the minimally-invasive, accurate, repeatable and objective measurement of body water and fat in living equids.
TL;DR: Waist-to-height ratio is emerging as a new anthropometric index with a potential for global use in different ethnic groups and in adults and children.
Abstract: Fat and lean components of the body including total body fat, fat-free mass and total body water and ectopic fat accumulation are important constituents that link obesity, aging, and chronic disease to subsequent morbidity and mortality. The methodology of body composition is based on a series of models characterized by progressive levels of anatomical complexity. A commonly used example is five-level model: atomic, molecular, cellular, tissue-system, whole body. Each body composition analysis method targets a component or a subcomponent of the five-level model of body composition. The choice of body composition analysis method greatly depends on the question being asked, the setting where the measurement is performed and the availability of measuring devices. Body composition analysis methods vary in complexity and precision, and range from simple field based methods to more technically challenging, laboratory based methods. Although several methods have been developed to assess body composition, anthropometric indices are simple, safe and cheap measures to quantify obesity. Body mass index, calculated from height and weight, is the most frequently used, quickest and the easiest measure. As body mass index does not differentiate peripheral from abdominal obesity, the use of waist circumference and waist-to-hip ratio was proposed in various guidelines. Waist-to-height ratio is emerging as a new anthropometric index with a potential for global use in different ethnic groups and in adults and children. The minimum measurements to be made in the basal evaluation of overweight patients are weight, height and waist circumference to calculate body mass index and waist-to-height ratio.
TL;DR: Overestimation of TBW by anthropomorphic-based equations would lead to a lower calculation of Kt/V(urea), which may lead to changes in peritoneal dialysis prescription to achieve clinical standard targets and also affect studies examining the relationship between KT/V and survival.
Abstract: Summary Background and objectives Peritoneal dialysis adequacy is typically assessed by urea clearance corrected for total body water (TBW) on the basis of anthropomorphic equations, which do not readily take into account changes in body composition, which may vary between ethnic groups. To determine whether ethnicity could affect estimates of peritoneal dialysis adequacy, we compared TBW estimated by anthropomorphic equations and that measured by multifrequency bioimpedance spectroscopy. Design, setting, participants, & measurements We calculated TBW in 600 healthy adult peritoneal dialysis outpatient attending two tertiary university hospitals serving an inner-city multiethnic population who had TBW measured by multifrequency bioimpedance spectroscopy performed. Results 600 adult peritoneal dialysis patients were studied: mean age, 56.7 0.6 years; 54.2% men; 29.7% diabetic; mean body mass index, 26.1 0.2; 47.3% Caucasian; 29.2% South Asian; 12.8% African/Afro-Caribbean. Total body water was calculated using several anthropomorphic equations and was higher than that calculated MEASURED BY MF-BIS for all ethnic groups, apart from African/Afro-Caribbeans, with the greatest difference between Watson calculated TBW and multifrequency bioelectrical impedance spectroscopy 12.3 0.6% for the South Asians, 9.0 2.6% for Far Eastern Asians, 2.8 0.6% Caucasians, and 0.2 1.5% for African/Afro-Caribbeans. Conclusions In this United Kingdom–based multiethnic population, body composition differed particularly for the South Asian patients compared with Caucasians and African/Afro-Caribbeans. Overestimation of TBW by anthropomorphic-based equations would lead to a lower calculation of Kt/Vurea, which may lead to changes in peritoneal dialysis prescription to achieve clinical standard targets and also affect studies examining the relationship between Kt/V and survival. Clin J Am Soc Nephrol 6: 2492–2498, 2011. doi: 10.2215/CJN.04130511
TL;DR: It is concluded that the improvement of body composition affects the number of stem/progenitor cells in circulation and the changes in body composition correlated with the level of lipoproteins responsible for the increased cardiovascular risk factors.
Abstract: Being overweight or obese is associated with an increased risk for the development of non-insulin-dependent diabetes mellitus, hypertension, and cardiovascular disease. Dyslipidemia of obesity is characterized by elevated fasting triglycerides and decreased high-density lipoprotein-cholesterol concentrations. Endothelial damage and dysfunction is considered to be a major underlying mechanism for the elevated cardiovascular risk associated with increased adiposity. Alterations in endothelial cells and stem/endothelial progenitor cell function associated with overweight and obesity predispose to atherosclerosis and thrombosis. In our study, we analyzed the effect of a low calorie diet in combination with oral supplementation by vitamins, minerals, probiotics and human chorionic gonadotropin (hCG, 125-180 IUs) on the body composition, lipid profile and CD34-positive cells in circulation. During this dieting program, the following parameters were assessed weekly for all participants: fat free mass, body fat, BMI, extracellular/intracellular water, total body water and basal metabolic rate. For part of participants blood chemistry parameters and circulating CD34-positive cells were determined before and after dieting. The data indicated that the treatments not only reduced body fat mass and total mass but also improved the lipid profile. The changes in body composition correlated with the level of lipoproteins responsible for the increased cardiovascular risk factors. These changes in body composition and lipid profile parameters coincided with the improvement of circulatory progenitor cell numbers. As the result of our study, we concluded that the improvement of body composition affects the number of stem/progenitor cells in circulation.
TL;DR: The results demonstrate that the postpartum period is associated with a preferential accumulation of adipose tissue in the visceral compartment, even though overall body weight is decreased.
Abstract: Parity is associated with weight retention and has long-lasting and detrimental effects on the health of women. Previous studies have shown that increasing parity was independently associated with an increased prevalence of metabolic syndrome. Postpartum weight is made up of several components including uterine and mammary tissues, body water (intracellular (ICW) and extracellular water (ECW)), and fat. These components change in variable amounts postpartum, thereby distinctly affecting the interpretation of individual weight retention; however, it is unclear which components contribute to weight retention. The aims of this longitudinal study were to evaluate changes in body composition during the postpartum period and to investigate their effects on weight retention. This prospective study examined 41 healthy, pregnant women who gave birth at Korea University Guro Hospital. We measured body composition at 2 days, 2 weeks, and 6 weeks postpartum using bioelectrical impedance analysis. Weight decreased during this postpartum period (P < 0.001); the postpartum weight retention from prepregnancy to 6 weeks postpartum was 4.43 ± 4.0 kg. Among various body composition components, ECW, ICW, total body water, and fat-free mass (FFM) decreased postpartum. However, fat mass (FM) and visceral fat area, the components that experienced the greatest changes, increased postpartum. Our results demonstrate that the postpartum period is associated with a preferential accumulation of adipose tissue in the visceral compartment, even though overall body weight is decreased. Further studies are needed to evaluate the changes in body composition over longer time periods and their long-term effects on health.
TL;DR: The study indicated that BCSE provided a better point estimation of ICW and TBW than XE and HE in body fluid volume point estimation in maintenance hemodialysis patients.
Abstract: Background. The accurate assessment of body fluid volume is important in many clinical situations. Hannan et al. proposed a single-frequency bioimpedance equation (HE) to calculate extracellular water (ECW) and total body water (TBW). There are two equations based on the bioimpedance spectroscopy (BIS) method for the evaluation of body fluid volume: Xitron equations (XE) and body composition spectroscopy equations (BCSE). The aim of the study was to compare the accuracy of these three equations in body fluid volume point estimation in maintenance hemodialysis (MHD) patients. Methods. The BIS method was performed in MHD patients before and after a hemodialysis (HD) session. TBW, ECW and intracellular water (ICW) were calculated by XE, BCSE and HE, respectively. Hydration status (HS) was calculated using inputs of XE, BCSE and HE. ICW before dialysis was compared to ICW after dialysis. The change of TBW and HS using different equations was compared to actual ultrafiltration volume (AUV) that was calculated as weight difference of pre- to postdialysis. Results. Fifty MHD patients (27 females) were included in the study. Significant changes in ICW were observed using the XE and HE method with ultrafiltration (XE: 15.51 6 5.07 versus 16.17 6 5.34 L, P 0.05). DTBW_XE and DTBW_HE were significantly different from AUV (XE 1.76 6 0.89 versus 2.46 6 0.89 L, P < 0.01; HE 4.16 6 1.36 versus 2.46 6 0.89 L, P < 0.01); however, DTBW_BCSE was much closer to AUV (2.27 6 0.90 versus 2.46 6 0.89 L, P ¼ 0.129). The change of HS using inputs of BCSE was also closer to AUV (2.41 6 0.86 versus 2.46 6 0.89 L, P ¼ 1.0). Conclusion. Our study indicated that BCSE provided a better point estimation of ICW and TBW.
TL;DR: The hypothesis that humans are the mammals with the greatest capacity for exercising in extreme heat is supported, by adopting a pacing strategy, high rates of ad libitum water intake, and by a small reduction in total body water to maintain serum sodium concentration.
Abstract: Guidelines to establish safe environmental exercise conditions are partly based on thermal prescriptive zones. Yet there are reports of self-paced human athletic performances in extreme heat. Eighteen participants undertook a 25-km route march in a dry bulb temperature reaching 44.3°C. The mean (± s) age of the participants was 26.0 ± 3.7 years. Their mean ad libitum water intake was 1264 ± 229 mL · h−1. Predicted sweat rate was 1789 ± 267 mL · h−1. Despite an average body mass loss of 2.73 ± 0.98 kg, plasma osmolality and serum sodium concentration did not change significantly during exercise. Total body water fell 1.47 kg during exercise. However, change in body mass did not accurately predict changes in total body water as a 1:1 ratio. There was a significant relationship (negative slope) between post-exercise serum sodium concentration and changes in both body mass and percent total body water. There was no relationship between percent body mass loss and peak exercise core temperature (39 ± 0...
TL;DR: There was moderate inter-observer agreement of overall clinical volaemic assessment of elderly hyponatraemic patients, and total body water estimation by bioelectrical impedance analysis correlates well with estimation by measurement of dilution of deuterium oxide, providing a potentially useful tool to improve the management of the elderly hyp onatraemic patient.
Abstract: Background: Hyponatraemia is the commonest electrolyte disturbance of hospital inpatients. Assessment of volaemic status is an important part of diagnosis and management.
Aim: To determine reliability of clinical assessment of volaemic state by assessing inter-observer variability of clinical measures of volaemic state. To assess validity of bioelectrical impedance analysis as a tool to measure total body water in elderly hyponatraemic patients.
Design: Observational study conducted in a Department of Medicine for the Elderly.
Methods: Hospital inpatients >65 years old ( n = 22) with serum sodium concentration <130 mmol/l were included. Two assessors determined volaemic state on two occasions 72 h apart. Level of agreement between observers was determined on each occasion. Total body water estimation was undertaken with bioelectrical impedance analysis and measurement of dilution of deuterium oxide. Correlation between these two measures was then analysed.
Results: Cohen’s κ for agreement between two observers for overall assessment of volaemic state was 0.59 ( P < 0.01). Values for agreement between individual clinical markers of volaemic state ranged between 0.16 and 0.45. Pearson correlation coefficient ( r ) for correlation between estimation of total body water undertaken by bioelectrical impedance analysis and by measurement of dilution of deuterium oxide was 0.69 ( P < 0.001).
Conclusion: There was moderate inter-observer agreement of overall clinical volaemic assessment of elderly hyponatraemic patients. Total body water estimation by bioelectrical impedance analysis correlates well with estimation by measurement of dilution of deuterium oxide, providing a potentially useful tool to improve the management of the elderly hyponatraemic patient.
TL;DR: The upper limits of human EE were determined and it was found that some elite humans are able to sustain PALs above 5.0 for a minimum of 10 d, suggesting catabolism of body tissue may be preventable in situations with proper energy intake.
Abstract: Migrating birds have been able to sustain an energy expenditure (EE) that is five times their basal metabolic rate. Although humans can readily reach these levels, it is not yet clear what levels can be sustained for several days.
Purpose: The study�s purposes were 1) to determine the upper limits of human EE and whether or not those levels can be sustained without inducing catabolism of body tissues and 2) to determine whether initial body weight is related to the levels that can be sustained.
Methods: We compiled data on documented EE as measured by doubly labeled water during high levels of physical activity (minimum of five consecutive days). We calculated the physical activity level (PAL) of each individual studied (PAL = total EE / basal metabolic rate) from the published data. Correlations were run to examine the relationship between initial body weight and body weight lost with both total EE and PAL.
Results: The uppermost limit of EE was a peak PAL of 6.94 that was sustained for 10 consecutive days of a 95-d race. Only two studies reported PALs above 5.0; however, significant decreases in body mass were found in each study (0.45�1.39 kg·wk-1 of weight loss). To test whether initial weight affects the ability to sustain high PALs, we found a significant positive correlation between TEE and initial body weight (r = 0.46, P < 0.05) but no correlation between PAL and body weight (r = 0.27, not statistically significant).
Conclusions: Some elite humans are able to sustain PALs above 5.0 for a minimum of 10 d. Although significant decreases in body weight occur at this level, catabolism of body tissue may be preventable in situations with proper energy intake. Further, initial body weight does not seem to affect the sustainability of PALs.
TL;DR: In this paper, the authors investigated whether multifrequency bioimpedance could detect differences in fluid distribution in the arms with haemodialysis in patients with different vascular access modalities.
Abstract: Introduction. Intradialytic hypotension remains the commonest complication of routine outpatient haemodialysis treatments. Multifrequency bioimpedance allows assessment of body fluid volumes. Multifrequency bioimpedance can potentially monitor changes in extracellular volume during dialysis and may therefore help to reduce intradialytic hypotension. Hypotension-prone patients have been reported to start dialysis with relatively more fluid distributed in the trunk than the arms. However, as arterio-venous fistulae are the preferred form of vascular access and fistulae could potentially affect fluid retention in the arm, we investigated whether multifrequency bioimpedance could detect differences in fluid distribution in the arms with haemodialysis in patients with different vascular access modalities.Methods. We audited the change in extracellular water (ECW) and total body water (TBW) in the arms following haemodialysis in 100 patients attending for routine outpatient haemodialysis at a university centre by multifrequency bioimpedance using an eight-electrode contact technique.Results. Patients with fistulae had greater ECW/TBW % in the fistula arm both prior to and post dialysis compared with central venous catheter (CVC) (pre 38.9 ± 0.1 vs 38.3 ± 0.1 and post 38.4 ± 0.1 vs 37.8 ± 0.1, P < 0.01), with a greater absolute difference between arms (0.53 ± 0.01 vs 0.05 ± 0.01, P < 0.01) and greater arm ECW/TBW % compared with total body ECW/TBW % predialysis (forearm fistula 99.4 ± 0.4 vs CVC 97.2 ± 0.3, P < 0.01).Conclusion. Absolute and also relative extracellular fluid volumes are increased in the fistula arm of haemodialysis patients. Thus, if algorithms are to be developed to monitor relative segmental changes in extracellular volumes to help prevent intradialytic hypotension using bioimpedance, then the dialysis vascular access and site will have to be considered, particularly if using relative changes in the upper limbs. Thus, alterative sites which are not so affected by vascular access, such as the calf, may prove advantageous.
TL;DR: Recalibration and cross-validation enables enhanced assessment of body composition in (pre)school children for use in epidemiological field studies and indicates that BIA underestimates total body water by 0.51 kg in ( pre-school children, when using the Kushner equation.
Abstract: Summary Background & aims Accurate field methods to assess body composition in young children are scarce. The aim of this study was to validate bioelectrical impedance analysis with deuterium based total body water analysis in (pre)school children. Methods We examined fifty-six 4–7 year old children, 36% boys. Total body water estimated with standardized single frequency bioelectrical impedance analysis was compared with deuterium dilution technique. An established equation (Kushner) was tested, recalibrated and subsequently cross-validated in an independent sample. Results Compared to deuterium dilution (mean total body water 12.66 kg, n = 56), bioelectrical impedance analysis underestimated total body water by 0.51 kg (p = 0.002) and this varied across the range of total body water (r = 0.41; p = 0.002). Recalibration of the equation yielded: total body water (kg) = 0.439 Height2 (cm2)/Resistance (Ω) + 0.027 Weight (kg) + 4.014 (R2 = 0.74, SEE = 0.96 kg). Application of this equation in the independent sample (n = 20) showed a non-significant bias in total body water (mean bias −0.30 kg, p = 0.17). Conclusions These data indicate that BIA underestimates total body water by 0.51 kg in (pre)school children, when using the Kushner equation. Recalibration and cross-validation enables enhanced assessment of body composition in (pre)school children for use in epidemiological field studies.
TL;DR: The two methodologies appear to produce similar Posm values when measured in most individuals, however, the potential for significant dilution (>3 mmol/kg) should be considered when choosing the pre-hydration methodology.
Abstract: A methodological discrepancy exists in the hydration assessment literature regarding the establishment of euhydration, as some investigations utilize a pre-hydration technique, while others do not (overnight fluid/food fast). However, the degree that plasma osmolality (Posm) dilutes when using the pre-hydration method and how body mass/composition might influence the results is not known. Thirty subjects (22 M, 8 F; 20 ± 2 years (mean ± SD); 1.8 ± 0.1 m; 75.8 ± 13.5 kg) had Posm measured after an 8-h food and fluid fast (overnight fast) and 90 min after a 500-mL (4–9 mL/kg) water bolus (pre-hydration). From pre- to post-bolus, participants’ Posm declined from 297 ± 3.5 to 295 ± 3.8 mmol/kg (p 0.05). The correlation between body mass or total body water and change in Posm was weak (p > 0.05), as was the correlation between relative fluid intake based on mass and change in Posm (p > 0.05). The two methodologies appear to produce similar Posm values when measured in most individuals. However, the potential for significant dilution (>3 mmol/kg) should be considered when choosing the pre-hydration methodology.
TL;DR: Fluid volumes in neonatal foals were found to be substantially larger than fluid volumes in adult horses and Multifrequency bioelectrical impedance analysis may be a useful technique for predicting TBW, ICFV, and ECFV in neonnatal foals.
Abstract: Objective—To determine values for total body water (TBW), extracellular fluid volume (ECFV), intracellular fluid volume (ICFV), and plasma volume (PV) in healthy neonatal (< 24 hours old) foals and to create a multifrequency bioelectrical impedance analysis (MF-BIA) model for use in neonatal foals. Animals—7 healthy neonatal foals. Procedures—Deuterium oxide (0.4 g/kg, IV), sodium bromide (30 mg/kg, IV), and Evans blue dye (1 mg/kg, IV) were administered to each foal. Plasma samples were obtained following an equilibration period, and the TBW, ECFV, ICFV, and PV were calculated for each foal. An MF-BIA model was created by use of morphometric measurements from each foal. Results—Mean ± SD values were obtained for TBW (0.744 ± 0.024 L/kg), ICFV (0.381 ± 0.018 L/kg), ECFV (0.363 ± 0.014 L/kg), and PV (0.096 ± 0.015 L/kg). The 95% limits of agreement between the MF-BIA and indicator dilution techniques were within ± 2 L for TBW and ECFV. Conclusions and Clinical Relevance—Fluid volumes in neonatal foals were...
TL;DR: There is a considerable association between severe forms of periodontal disease in males and their body composition, but this preliminary finding needs to be confirmed in more extensive studies.
Abstract: Obesity in humans might increase the risk of periodontitis. The aim of the present study was to examine the relationship between body composition of males and their periodontal status. AS total of 150 males (aged 30–60) were selected: 31 were periodontally healthy, 45 had gingivitis, 39 had initial periodontitis, and 35 suffered from established periodontitis. BMI (body mass index), WC (waist circumference), and body composition parameters (consisting of body water, body fat, and skeletal muscle and bone mass) were measured. After adjusting for age, history of diabetes, smoking, physical activity status, and socioeconomic status, statistically significant correlations were found between periodontitis and BMI, WC, and body composition. There was only a statistically significant difference between the periodontal health and established periodontitis; that is, periodontal disease in mild forms (gingivitis) and initial periodontitis do not influence these variables (BMI, WC, and body composition parameters) and only the severe form of the disease influences the variables. These data suggest that there is a considerable association between severe forms of periodontal disease in males and their body composition, but this preliminary finding needs to be confirmed in more extensive studies.
TL;DR: The correlation between BMI and body fat and WH ratio were much higher than the correlation between weight and fat andWH ratio.
Abstract: This study was carried out to investigate distribution of obesity, body composition, weight control and dietary behaviors, and to analyze the relationship between Body Mass Index (BMI) and physical characteristics, body composition and dietary behaviors by anthropmetric measurement and questionnaires. The 199 study subjects were divided into 3 age groups; 30's (78), 40's (77) and 50's (44) and 4 groups by BMI ; under weight (4.5%), normal (51.3%), over weight (26.1%) and obese (18.1%). Amount of skeletal muscle, body water, mineral and body fat were significantly increased with BMI. There were especially significant increase skeletal muscle 5.3 kg (19.1→ 23.5 kg), body water 5.3 kg (26.3→ 31.6 kg) and fat 15.2 kg (11.2→ 26.4 kg) from under weight to obesity group, respectively (p < 0.01). There were significantly decreased in the ratio of body water (10.3%), protein (2.7%) and body mineral (1.1%) from under weight to obesity, but significant increase 14.1% in body fat (p < 0.001). About 44.4% of under weight group and 40.1% of normal group and 50% of over and obesity group had dissatisfaction on their body images. Most of the women were concerned about their body images and experienced weight control. Dietary behavior scores of obesity group were significant lower than the other four groups (p < 0.001). There were significant positive correlation between BMI and body water (r = 0.62), protein (r = 0.52), skeletal muscle (r = 0.63), body fat (r = 0.91) and WH ratio (r = 0.91), respectively (p < 0.001). The correlation between BMI and body fat and WH ratio were much higher than the correlation between weight and fat and WH ratio. (Korean J Community Nutr 16(4) : 454~465, 2011) KEY WORD : BMI·body composition·body fat·weight control·dietary behavior
TL;DR: The total body fat in male diabetics of both age groups to be greater than that in controls, and the relative percentage of active body mass was greater in the healthy individuals than in diabetic patients.
Abstract: Introduction Type 2 diabetes is a metabolic disorder and as such should affect the components of body composition of diabetics. The changes it induces in patients complement the anthropological characteristics of this disease. The AIM of the present study was to assess the effect type 2 diabetes has on some of the body composition components in male diabetics. Material and methods The study included 169 male patients with type 2 diabetes. All patients (ethnical Bulgarian) were allocated into two age groups: group 1--patients aged 40-60 years and group 2--patients aged 61-80 years. Direct measurements of parameters were performed with a Tanita body composition analyser. The bioimpedance parameters we measured were body fat percentage (%BF), total body water percentage (%TBW), muscle mass (MM), bone mass (BM), and visceral fat (VF). The derived parameters were total body fat (TBF) (kg), active body mass (ABM) (kg), active body mass percentage. Results Body composition of male diabetics aged 40-60 years: %BF, VF and TBF were statistically significantly higher in diabetics than in healthy controls. Body composition of male diabetic patients aged 61-80 years: BM and VF were significantly higher in diabetic patients than in controls. %BF and MM did not have a high statistical significance. Inter-age comparison of body composition in male diabetics: we found that %BF, %TBW, MM and BM tend to be higher in 40-60-year-olds. Visceral fat was increased in the 61-80-year-olds, the difference reaching high statistical significance. Conclusion Bioimpedance analysis (BIA) of body composition showed the total body fat in male diabetics of both age groups to be greater than that in controls. TBF was greater in the younger age group at the expense of the subcutaneous fat, while in the more elderly patients it was the visceral fat that was increased, which makes their body composition correlate rather adversely with the prognosis, course and outcome of the disease. The relative percentage of active body mass was greater in the healthy individuals than in diabetic patients. This parameter was higher in the younger age group of diabetic patients than in the more elderly patients; this finding is probably due to the longer duration of the disease and also to aging changes such as osteoporosis, muscle atrophy and decreased quantities of body water.
TL;DR: The exclusion of suprailiac skinfold in the calculation, yielding to non-significant (P < 0.05) bias, improved the prediction of body composition in Cameroonian lactating women using the Durnin-Womersley and Siri equations.
TL;DR: It is concluded that multifrequency whole-body BIA may have clinical value in the estimation of dry weight and other haemodynamic parameters of haemodialysis and so may protect patients from the risks associated with under- or over-hydration.
Abstract: Adequate fluid management plays an important role in the treatment of haemodialysis patients and the assessment of dry weight is important for efficient therapy. Fluid volume parameters were assessed in adults undergoing haemodialysis for end-stage renal disease, using whole-body multifrequency bioimpedance analysis (BIA), and their relationship to haemodynamic and biochemical parameters of haemodialysis was evaluated. Ultrafiltration volume was correlated with age, sodium, haemoglobin, extracellular water (ECW)/total body water (TBW) ratio and ECW/intracellular water (ICW) ratio. The ECW/TBW ratio was correlated with age, body mass index, dry weight, predialysis systolic and diastolic blood pressure, and ECW/total body weight ratio. The ECW/ICW ratio correlated with age, dry weight, TBW, albumin, adequacy of dialysis and urea removal ratio. The study demonstrated a close relationship between bioimpedance-derived fluid volume parameters and the haemodynamic and biochemical parameters of haemodialysis. It ...
TL;DR: No steady state in metabolism was observed and no regular decrease of subcutaneous adipose tissue resulted, and this result is backed up by the nuclear magnetic resonance (NMR) urine analysis.
Abstract: We evaluated the change in body mass including fat mass and skeletal muscle mass in one ultracyclist whilst cycling 1,000 km in 48 hours at a constant intensity of ∼48% VO2max, corresponding to a heart rate frequency of ∼105 ± 5 bpm. A 1 kg fat mass decrease resulted, with the largest decrease occurring between the 12th and the 24th hour. No steady state in metabolism was observed and no regular decrease of subcutaneous adipose tissue resulted. This result is backed up by the nuclear magnetic resonance (NMR) urine analysis. Body water increase with simultaneous dehydration is possibly due to endocrine-induced renal water retention, in order to maintain metabolism processes that are required for energy supply and blood flow during very prolonged exercise. Both applied methods, the anthropometric and the bioelectrical impedance analysis, analyse fluid accumulation—especially in the skinfolds of the lower extremities—apparently incorrectly as an increase in body mass and not as an increase in fluids.