Analysis of hemodynamics and impedance using bioelectrical impedance analysis in hypovolemic shock-induced swine model.

To treat hypovolemic shock, fluid infusion or blood transfusion is essential to address insufficient volume. Much controversy surrounds resuscitation in hypovolemic shock. We aimed to identify the ideal fluid combination for treating hypovolemic shock-induced swine model, analyzing bioelectrical impedance and hemodynamics. Fifteen female three-way crossbred pigs were divided into three different groups. The three resuscitation fluids were (1) balanced crystalloid, (2) balanced crystalloid + 5% dextrose water, and (3) balanced crystalloid + 20% albumin. The experiment was divided into three phases and conducted sequentially: (1) controlled hemorrhage (1 L bleeding, 60 min), (2) resuscitation phase 1 (1 L fluid infusion, 60 min), and (3) resuscitation phase 2 (1 L fluid infusion, 60 min). Bioelectrical impedance analysis was implemented with a segmental multifrequency bioelectrical impedance analyzer. A total of 61 impedance measurements were assessed for each pig at six different frequencies in five segments of the pig. Pulse rate (PR), mean arterial pressure (MAP), stroke volume (SV), and stroke volume variation (SVV) were measured using a minimally invasive hemodynamic monitoring device. The three-dimensional graph showed a curved pattern when infused with 1 L of balanced crystalloid + 1 L of 5% dextrose water and 1.6 L of balanced crystalloid + 400 ml of 20% albumin. The 1M impedance increased in all groups during the controlled hemorrhage, and continuously decreased from fluid infusion to the end of the experiment. Only balanced crystalloid + 20% albumin significantly restored MAP and SV to the same level as the start of the experiment after the end of fluid infusion. There were no significant differences in MAP and SV from the time of recovery to the initial value of 1M impedance to the end of fluid infusion in all groups. The change and the recovery of hemodynamic indices such as MAP and SV coincide with the change and the recovery of 1M impedance. Using balanced crystalloid mixed with 20% albumin in hypovolemic shock-induced swine model may be helpful in securing hemodynamic stability, compared with balanced crystalloid single administration.

Comparison of body composition measures assessed by bioelectrical impedance analysis versus dual-energy X-ray absorptiometry in the United Kingdom Biobank.

BACKGROUND: Bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA) serves as common modalities for body composition assessment. This study was aimed to evaluate the agreement between BIA and DXA measures in UK Biobank. METHODS: UK Biobank participants with body fat mass (FM) and fat-free mass (FFM) estimates obtained through BIA (Tanita BC418MA) and DXA concurrently were included. Correlation between BIA and DXA-derived estimates were assessed with Lin's concordance correlation coefficients. Bland-Altman and Passing-Boblok analyses were performed to quantify the difference and agreement between BIA and DXA. Multivariable linear regression was used to identify predictors influencing the differences. Finally, prediction models were developed to calibrate BIA measures against DXA. RESULTS: The analysis included 34437 participants (female 51.4%, mean age 64.1 years at imaging assessment). BIA and DXA measurements were highly correlated (Lin's concordance correlation coefficient 0.94 for FM and 0.94 for FFM). BIA (Tanita BC418MA) underestimates FM overall by 1.84 kg (23.77 vs. 25.61, p < 0.01), and overestimated FFM overall by 2.56 kg (52.49 vs. 49.93, p < 0.01). The BIA-DXA differences were associated with FM, FFM, BMI and waist circumference. The developed prediction models showed overall good performance in calibrating BIA data. CONCLUSION: Our analysis exhibited strong correlation between BIA (Tanita BC418MA)- and DXA-derived body composition measures at a population level in UK Biobank. However, the BIA-DXA differences were observed at individual level and associated with individual anthropometric measures. Future studies may explore the use of prediction models to enhance the calibration of BIA measures for more accurate assessments in UK Biobank.

A 3 MHz Low-Error Adaptive Howland Current Source for High-Frequency Bioimpedance Applications.

Bioimpedance is a diagnostic sensing method used in medical applications, ranging from body composition assessment to detecting skin cancer. Commonly, discrete-component (and at times integrated) circuit variants of the Howland Current Source (HCS) topology are employed for injection of an AC current. Ideally, its amplitude should remain within 1% of its nominal value across a frequency range, and that nominal value should be programmable. However, the method's applicability and accuracy are hindered due to the current amplitude diminishing at frequencies above 100 kHz, with very few designs accomplishing 1 MHz, and only at a single nominal amplitude. This paper presents the design and implementation of an adaptive current source for bioimpedance applications employing automatic gain control (AGC). The "Adaptive Howland Current Source" (AHCS) was experimentally tested, and the results indicate that the design can achieve less than 1% amplitude error for both 1 mA and 100 µA currents for bandwidths up to 3 MHz. Simulations also indicate that the system can be designed to achieve up to 19% noise reduction relative to the most common HCS design. AHCS addresses the need for high bandwidth AC current sources in bioimpedance spectroscopy, offering automatic output current compensation without constant recalibration. The novel structure of AHCS proves crucial in applications requiring higher ß-dispersion frequencies exceeding 1 MHz, where greater penetration depths and better cell status assessment can be achieved, e.g., in the detection of skin or breast cancer.

Bioimpedance analysis predicts worsening events in outpatients with heart failure and reduced ejection fraction.

AIMS: Heart failure (HF) with reduced left ventricle ejection fraction (LVEF) is an entity with poor prognosis characterized by decompensations. Bioelectrical impedance analysis (BIA) is used to assess volume overload (VO) and may be useful to identify apparently stable HF outpatients at risk of decompensation. The aim of this study is to analyse whether VO assessed by BIA is associated with worsening heart failure (WHF) in stable outpatients with HF and reduced LVEF (HFrEF). METHODS AND RESULTS: This is a prospective single-centre observational study. Consecutive stable HF outpatients with LVEF below 40% underwent BIA, transthoracic echocardiography, blood sampling, and physical examination and were followed up for 3 months. VO was defined as the difference between the measured weight and the dry weight assessed by BIA. Demographic, clinical, anthropometric, echocardiographic, and analytical parameters were recorded. The primary endpoint was WHF, defined by visits to the emergency department for HF or hospitalization for HF. A total of 100 patients were included. The median VO was 0.5 L (interquartile range 0-1.6 L). Eleven patients met the primary endpoint. Univariate binary logistic regression analysis showed that left ventricle filling pressures assessed by E/e', N-terminal pro B-type natriuretic peptide, inferior vena cava dilatation (≥21 mm), signs of congestion, and VO were associated with the primary endpoint. Binary logistic regression multivariate analysis showed that VO was the only independent predictor for the primary endpoint (adjusted OR 2.7; 95% CI 1.30-5.63, P = 0.008). Multivariate Cox regression analysis also showed an adjusted hazard ratio (HR) for VO of 2.03; 95% CI 1.37-3.02, P < 0.001. Receiver-operating characteristic curve analysis showed an area under the curve for VO of 0.88 (95% CI 0.79-0.97, P < 0.001) with an optimal cut-off of 1.2 L. CONCLUSIONS: VO assessed by BIA is independently associated with WHF in stable outpatients with HFrEF at 3 months.

Assessing the nutritional status and impact of a series of nutritional interventions on elderly inpatients using bioelectrical impedance analysis: A service evaluation.

BACKGROUND: The aim of the study was to use bioelectrical impedance analysis (BIA) to assess nutritional status of elderly patients admitted to hospital and quantitatively measure the impact of the Cardiff and Vale University Health Board (CAVUHB) model ward. Secondary objectives were to assess the feasibility of using BIA in this patient population and compare nutrition risk screening tools against fat-free mass index (FFMI). METHODS: A prospective, comparative, single-centre, service evaluation of a 'model ward for nutrition and hydration' undertaken in medical and rehabilitation beds in a large UK teaching hospital. RESULTS: A total of 450 BIA measurements were taken using a Bodystat Multiscan 5000 on 162 patients; several patients had repeated measurements during their hospital stay. Patients tolerated the procedure well, but lack of accurate weight, implanted medical devices and tissue viability precluded some participants. CONCLUSIONS: BIA is quick, non-invasive, simple to complete and can elicit huge data about an individual's body composition. In a larger cohort of medical admissions, BIA could assist in identifying the sensitivity and specificity of the nutrition screening tools. The collective benefit of a series of nutritional interventions preserved nutritional status better in this elderly inpatient population than usual models of care. Although results were not statistically significant, there is an opportunity with the new model of care to better support frail patients and prevent deconditioning.

Association of Body Water Balance, Nutritional Risk, and Sarcopenia with Outcome in Patients with Acute Ischemic Stroke: A Single-Center Prospective Study.

In the present study, we examined the inter-relationships between body water balance, nutritional risk, sarcopenia, and outcome after acute ischemic stroke (AIS) in patients who were living independently. We defined abnormal body water balance as overhydration, with an extracellular fluid/total body water ratio > 0.390. A geriatric nutritional risk index (GNRI) < 98 was considered low GNRI. Sarcopenia was defined according to the 2019 Asian Working Group for sarcopenia criteria. Poor outcome was defined as a modified Rankin scale (mRS) score ≥ 3 at discharge. Among 111 eligible patients (40 females, median age: 77 years), 43 had a poor prognosis, 31 exhibited overhydration, 25 had low GNRI, and 44 experienced sarcopenia. Patients with poor outcomes had significantly higher National Institutes of Health Stroke Scale (NIHSS) scores, which were significantly more common with overhydration, low GNRI, and sarcopenia (p < 0.001 for all). Concomitant overhydration, low GNRI, and sarcopenia were associated with poorer outcomes. In multivariate analysis, overhydration [odds ratio (OR) 5.504, 95% confidence interval (CI) 1.717-17.648; p = 0.004], age (OR 1.062, 95%CI 1.010-1.117; p = 0.020), and NIHSS score (OR 1.790, 95%CI 1.307-2.451; p < 0.001) were independent prognostic factors for poor outcome. The results indicated that the combination of overhydration, low GNRI, and sarcopenia predict poor outcomes following AIS. Overhydration was particularly associated with poor outcomes.

Factors associated with an improvement in extracellular water-to-total body water ratio in older adults with hip fractures: A decision tree analysis.

BACKGROUND & AIMS: The extracellular water-to-total body water ratio (ECW/TBW) increases with age and after fractures. A high ECW/TBW may hinder improvements in physical function and skeletal muscle mass. However, the effects of ECW/TBW improvement have not been properly investigated. The aim of this study was to investigate the factors associated with ECW/TBW improvement in older adults with hip fractures. METHODS: This retrospective cohort study included 203 patients with hip fractures who were admitted to a convalescent rehabilitation ward. ECW/TBW and skeletal muscle mass index (SMI) were measured using bioelectrical impedance analysis. The patients were classified into two groups: those with an improvement in ECW/TBW (n = 123) and those without an improvement (n = 80). Decision tree analysis was performed to examine the factors associated with ECW/TBW improvement. As a secondary objective, a multiple regression analysis was performed to identify the factors associated with SMI gain. RESULTS: Decision tree analysis identified rehabilitation volume and protein intake as the first and second factors most significantly associated with an improvement in ECW/TBW, respectively. Multiple regression analysis showed that improved ECW/TBW (ß: 0.400, p < 0.001) was significantly associated with SMI gain. CONCLUSIONS: Rehabilitation volume and protein intake are clinically important for improving ECW/TBW in older adults with hip fractures.

Impact of volume indices in bioelectrical impedance measurement on the assessment of cardiac function indices by echocardiography in hemodialysis patients.

INTRODUCTION: Cardiovascular events resulting from volume overload are a primary cause of mortality in hemodialysis patients. Bioelectrical impedance analysis (BIA) is significantly valuable for assessing the volume status of hemodialysis (HD) patients. In this article, we explore the correlation between the volume index measured by BIA and the cardiac function index assessed by echocardiography (ECG) in HD patients. METHODS: Between April and November 2018, we conducted a cross-sectional study involving randomly selected 126 maintenance HD patients. Comprehensive data on medical history and laboratory test results were collected. Subsequently, we investigated the correlation between volume indices measured by BIA and cardiac function parameters by ECG. RESULTS: We discovered a significant correlation between the volume indices measured by BIA and various parameter of cardiac function. The Left Ventricular Hypertrophy (LVH) group exhibited higher levels of the percentage of Extracellular Water (ECW%) and the percentage of Total Body Water (TBW%) compared to the Non-LVH group. Extracellular Water (ECW) and Third Interstitial Fluid Volume (TSFV) were identified as independent risk factors for Left Ventricular Mass (LVM), and both demonstrated a high predictive value for LVM. ECW% emerged as an independent risk factor for the Left Ventricular Mass Index (LVMI), with a high predictive value for LVMI. CONCLUSION: ECW and TSFV were found to be positively associated with cardiac function parameters in HD patients.

Influence of the COVID-19 pandemic on the incidence of eating disorders.

INTRODUCTION: Eating disorders (EDs) develop more frequently in young females. Following the COVID-19 pandemic, there has been evidence of an increase in children and adolescents, with an earlier onset and a worse body weight and nutritional status. The aim of this study was to determine whether this trend has also been observed in our region over the past 6 years. MATERIAL AND METHODS: We conducted a retrospective and descriptive cohort study in paediatric patients with a diagnosis of ED, referred during the 3 years preceding and following the declaration of the state of alarm due to the pandemic. We analysed and compared clinical, anthropometric and laboratory variables and bioelectrical impedance and bone density data. RESULTS: Of the 129 patients in the sample, 28 were referred before the lockdown period and 101 after. When we compared these groups, we found a longer time elapsed from onset to the initial assessment (mean delay, 11.87 [SD, 6.75] vs. 6.64 [SD, 4.36] months), a greater hospitalization rate (14.1% vs. 10.1%), and lower vitamin D values (mean level, 28.19 [SD, 9.95] vs. 34.39 [SD, 11.87] ng/mL) in the post-lockdown group. We also found a greater frequency of self-harm suicide attempts in these patients. CONCLUSIONS: This study confirms the increasing trend in EDs in children and adolescents in our area. Moreover, we found differences in the clinical characteristics and time elapsed to diagnosis compared to the patients referred to the hospital before the pandemic.

The Influence of the Energy Intake Variability During the Week on the Body Composition in an Adult Population.

Background: The regularity of eating, together with other nutritional factors, is one of the important determinants of health. According to previous studies, it is not clear if a greater fluctuation in energy intake is associated with higher body fat and weight gain, or if the weight of people is stable despite these fluctuations in the energy intake. The aim of the study was to verify if a higher variability in the energy intake each day of the week is related to the amount of body fat and other anthropometric parameters. Methods: A total of 220 (151 women, 69 men) individuals of Czech Caucasian origin with a BMI of 18.3-58 kg/m2, aged 21.7-79.7 were included in the study. Selected anthropometric characteristics were measured using a bioelectrical impedance analysis. 7-day food records were completed and analyzed using nutritional software. The measured values were statistically evaluated by multiple linear regression analysis. Results: The results of the multiple linear regression showed the statistically significant dependence of the percentage of body fat (p<0.01), BMI (p<0.01), and waist circumference (p<0.05) on the relative variability of the daily energy intake. Conclusions: The results of our study suggest that people with more regular energy intake also have better anthropometric parameters related to their cardiometabolic health.

Usefulness of bioelectrical impedance analysis in multiple sclerosis patients-the interrelationship to the body mass index.

Background: Patients with multiple sclerosis (MS) have many potential factors (disease duration, spasticity, immobilization, or glucocorticoid use) that can deteriorate their nutritional status and impact both the progression and prognosis of the disease. Body mass index (BMI), the most widely used nutritional status assessment tool, has important limitations because it does not provide any data on body composition. Aim: This study aimed to assess the interrelationship between nutritional status assessment by both body mass index (BMI) and body composition using bioelectrical impedance analysis (BIA) and the consistency of diagnosis for underweight/underfat, normal weight/healthy, overweight/overfat, and obesity/obese MS patients. Methods: Anthropometric [BMI and waist-to-height ratio (WHtR)] and body composition (BIA) data were evaluated in 176 patients with MS. Patients were categorized into four nutritional status subgroups (underweight, normal weight, overweight, obese according to BMI, and underfat, healthy, overfat, and obese according to fat mass% by BIA). The median Expanded Disability Status Scale score was 4.5. Patients were then divided according to EDSS score as mild (EDSS 1.0-4.0) or moderate (EDSS 4.5-6.5) disability subgroups. Results: Based on BIA assessment, there was a significantly higher prevalence of overfat than of overweight based on BMI [n = 50 (28.41%) vs. n = 38 (21.59%); p < 0.05]. However, the prevalence of obesity did not differ significantly regardless of the mode of diagnosis and was not significantly lower when assessed using BIA [n = 26 (14.77%) vs. n = 30 (17.05%), respectively]. The overall compatibility rates (CR) of diagnoses made using both BMI and BIA were 75.6, 77.0, and 70.1% for all patients with MS and the mild and moderate subgroups, respectively. The lowest CR was observed in the overweight group. Adiposity significantly underestimated BMI in all subgroups. In the moderate MS subgroup, BMI significantly overcategorized patients with MS as having a normal weight (p < 0.05). Stratification for abdominal obesity (WHtR > 0.5) showed that BMI significantly underestimated the prevalence of MS in overweight and obese vs. overfat and obese patients, as assessed using BIA (60.5 vs. 67%; p < 0.05). Clinical status (EDSS and ΔEDSS) was more closely related to the nutritional status categorized by FAT% assessed using BIA than using BMI cutoff points. However, the relationship was not statistically significant. Conclusion: Using the BMI cutoff point for nutritional status assessment in patients with MS is associated with a significant underestimation of excess fat mass. BIA-based FAT% based on BIA have a better relationship with abdominal obesity and disability status than with BMI in patients with MS. The highest rate of false-negative diagnoses was based on the BMI in patients with MS and moderate disability. Adiposity assessment using BIA appears to be a useful method for proper nutritional status assessment in the patients group.

Preoperative body composition measured by bioelectrical impedance analysis can predict pancreatic fistula after pancreatic surgery.

BACKGROUND: Postoperative pancreatic fistula (POPF) remains one of the most severe complications after pancreatic surgery. The methods for predicting pancreatic fistula are limited. We aimed to investigate the predictive value of body composition parameters measured by preoperative bioelectrical impedance analysis (BIA) on the development of POPF. METHODS: A total of 168 consecutive patients undergoing pancreatic surgery from March 2022 to December 2022 at our institution were included in the study and randomly assigned at a 3:2 ratio to the training group and the validation group. All data, including previously reported risk factors for POPF and parameters measured by BIA, were collected. Risk factors were analyzed by univariable and multivariable logistic regression analysis. A prediction model was established to predict the development of POPF based on these parameters. RESULTS: POPF occurred in 41 of 168 (24.4%) patients. In the training group of 101 enrolled patients, visceral fat area (VFA) (odds ratio [OR] = 1.077, P = 0.001) and fat mass index (FMI) (OR = 0.628, P = 0.027) were found to be independently associated with POPF according to multivariable analysis. A prediction model including VFA and FMI was established to predict the development of POPF with an area under the receiver operating characteristic curve (AUC) of 0.753. The efficacy of the prediction model was also confirmed in the internal validation group (AUC 0.785, 95% CI 0.659-0.911). CONCLUSIONS: Preoperative assessment of body fat distribution by BIA can predict the risk of POPF after pancreatic surgery.

Body Fat Distribution and Left Atrial Reverse Remodeling After Catheter Ablation for Atrial Fibrillation.

Background: Emerging evidence suggests a pathophysiological link between obesity and atrial fibrillation (AF). However, the contribution of body fat distribution to left atrial (LA) remodeling and its reversibility remain unclear in nonobese AF patients. Objectives: The purpose of this study was to investigate the association of body fat distribution with LA size and reverse remodeling (LARR). Methods: In total, 116 nonobese patients with AF (88 men, age 63 ± 11 years) who underwent first catheter ablation (CA) were included. Body fat distribution was assessed with bioelectrical impedance, and body fat percentage (BF%) and central fat percentage (CF%) were calculated. Patients were categorized by body size metrics (body mass index [BMI] and waist-to-hip [W/H] ratio) and fat parameters (BF% and CF%). Echocardiography was performed before and 6 months after CA. Multivariable logistic regression was used to examine the association between the 4 metrics (ie, BMI, W/H ratio, BF%, and CF%) and a lack of LARR (<15% reduction or increase in the LA volume index). Results: Body size metrics and adiposity measures were not independently associated with baseline LA size. Six months after CA, the higher W/H ratio and CF% groups exhibited persistent LA enlargement compared to their counterparts (both P < 0.01). In the multivariable analysis, W/H ratio and CF% were associated with a lack of LARR (adjusted ORs of 3.86 and 2.81 per 0.10 and 10% increase, respectively, both P < 0.01). The combined assessment of CF% with W/H ratio provided complementary risk stratification for persistent LA enlargement. Conclusions: Central adiposity was associated with a lack of LARR after CA, highlighting the importance of assessing body fat distribution even in nonobese patients.

Agreement between fat-free mass from bioelectrical impedance analysis and dual-energy X-ray absorptiometry and their use in estimating resting metabolic rate in resistance-trained men.

BACKGROUND: This study aimed to determine the agreement between fat-free mass (FFM) estimates from bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA) and their use in estimating resting metabolic rate (RMR) in men undergoing resistance training. METHODS: Thirty healthy resistance-trained men (22.7 ± 4.4 years, 70.0 ± 8.7 kg, 174.6 ± 6.7 cm, and 22.9 ± 2.3 kg/m2) were evaluated. The equation developed by Tinsley et al. (RMR = 25.9 × fat-free mass [FFM] + 284) was adopted to calculate the RMR. DXA was used as the reference method for FFM. RESULTS: Furthermore, FFM was also estimated by BIA using a spectral device. No significant difference (p > 0.05) was observed between DXA (1884.2 ± 145.5 kcal) and BIA (1849.4 ± 167.7 kcal) to estimate RMR. A positive and significant correlation (r = 0.89, p < 0.05) was observed between DXA and BIA estimates of RMR. The mean difference between methods indicated that BIA presented a bias of -34.8 kcal. CONCLUSION: These findings suggest that using FFM derived from DXA or BIA results in similar RMR estimates in resistance-trained men.

Associations of upper- and lower-limb muscle strength, mass, and quality with health-related quality of life in community-dwelling older adults.

AIM: This study aimed to investigate the associations between upper- and lower-limb muscle strength, mass, and quality and health-related quality of life (HRQoL) among community-dwelling older adults. METHODS: A cross-sectional study was conducted with 428 Brazilian community-dwelling older adults aged 60 to 80 years. Upper- and lower-limb muscle strength were evaluated through the handgrip strength (HGS) test and the 30-s chair stand test, respectively. Muscle mass was assessed by dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA). Muscle quality was evaluated using the muscle quality index (MQI). HRQoL was assessed using the World Health Organization Quality of Life Brief Version questionnaire. RESULTS: Lower-limb, but not upper-limb, muscle strength and quality were independently associated with HRQoL, particularly within the domains of physical capacity, environment, and overall HRQoL for both males and females (P < 0.05). DXA- and BIA-derived analyses provided similar results in relation to muscle mass and muscle quality. CONCLUSIONS: Lower-limb, but not upper-limb, muscle strength and quality were independently associated with HRQoL among community-dwelling older adults. Moreover, the results obtained from both BIA and DXA were similar, highlighting that BIA can serve as a viable surrogate method for estimating body composition in resource-limited clinical settings. Geriatr Gerontol Int 2024; 24: 683-692.

Water temperature affects somatic growth, body condition and oxygen and carbon otolith isotopes of stout whiting (Sillago robusta).

Ocean warming will continue to affect the growth, body condition and geographic distributions of marine fishes and understanding these effects is an urgent challenge for fisheries research and management. Determining how temperature is recorded in fish otolith carbonate, provides an additional chronological tool to investigate thermal histories, preferences and patterns of movement throughout an individual's life history. The influence of three water temperature treatments (22°C, 25°C, and 28°C) on hatchery-reared juvenile stout whiting, Sillago robusta, was tested using a controlled outdoor mesocosm system. Fish were measured for change in length and weight, and body condition was determined using bioelectrical impedance analysis. Sagittal otoliths were analysed for stable oxygen (δ18Ootolith) and carbon (δ13Cotolith) isotopes via isotope ratio mass spectrometry. Whiting kept at 22°C were significantly smaller and had diminished body condition compared to fish in 25°C and 28°C, which did not significantly differ from each other. The δ18O otolith values of stout whiting demonstrated a negative temperature-dependent fractionation relationship which was similar in slope but had a different intercept to the relationships reported for inorganic aragonite and other marine fish species. The δ13C otolith values also showed a negative relationship with water temperature, and the calculated proportion of metabolic carbon M in otoliths differed between fish reared in the coolest (22°C) and warmest (28°C) temperature treatments. Overall, the results suggest that stout whiting may have reached an upper growth threshold between 25°C and 28°C, and that growth and body condition may be optimised during warmer seasons and toward the northerly regions of their distribution. Otolith oxygen thermometry shows promise as a natural tracer of thermal life history, and species-specific fractionation equations should be utilised when possible to prevent errors in temperature reconstructions of wild-caught fish.

A Cross-Sectional Validation Study of Camry EH101 versus JAMAR Plus Handheld Dynamometers in Colorectal Cancer Patients and Their Correlations with Bioelectrical Impedance and Nutritional Status.

BACKGROUND: Reduced muscle strength (dynapenia) and mass (atrophy) are prognostic factors in oncology. Measuring maximal handgrip strength with dynamometers is feasible but limited by the cost of the reference device (JAMAR). METHODS: A cross-sectional study was conducted on colorectal cancer outpatients treated with chemotherapy or under active surveillance in our center from September 2022 to July 2023. Accuracy, reliability, and concordance were compared for two handheld dynamometers: the JAMAR Plus (the gold-standard device) and the Camry EH101 (a low-cost index device). A simultaneous nutritional diagnosis with GLIM criteria and bioelectrical impedance analysis (BIA) was carried out. RESULTS: A total of 134 participants were included. The median of maximal strength for the JAMAR Plus had a non-significant difference of 1.4 kg from the Camry EH101. The accuracy and reliability of the devices were high. Bland-Altman analysis showed a 0.8 kg bias and -4.1 to 5.6 kg limits of agreement (LoA); a 0.1 kg bias and -5.3 to 5.4 kg LoA in men; a 1.5 kg bias and -2.2 to 5.3 kg LoA in women. In total, 29.85% of the participants were malnourished. Prevalence of dynapenia increased from 3.67% with the JAMAR Plus to 5.14% with the Camry EH101. Both devices had a moderate and significant correlation with BIA-estimated muscle mass. CONCLUSIONS: The Camry EH101 was a cost-effective alternative to JAMAR Plus in our sample.

Assessing the Role of Bioelectrical Impedance Vector Analysis in Prognosis and Prevention of Contrast-Associated Acute Kidney Injury After Percutaneous Coronary Intervention.

This study evaluated the impact of Bioelectrical Impedance Vector Analysis (BIVA)-guided hydration therapy on contrast-associated acute kidney injury (CA-AKI) in patients undergoing percutaneous coronary intervention (PCI). From April 2022 to January 2023, this prospective study at the Eastern General Hospital of the Chinese People's Liberation Army involved 902 adults with stable coronary artery disease (CAD) scheduled for PCI. BIVA measurements were performed pre-contrast, followed by a standard hydration regimen. The study focused on the development of CA-AKI and major adverse cardiovascular events (MACE, including all-cause death, nonfatal myocardial infarction, and target vessel revascularization) within 1 year post-PCI. Among the 902 patients (average age: 60.8 years, 65.2% men), CA-AKI post-PCI was observed in 10.8%. Those with CA-AKI had more comorbidities and higher baseline creatinine levels. The contrast volume-to-estimated Glomerular Filtration Rate (eGFR) ratio was higher in CA-AKI patients, with a significantly increased resistance/height ratio (R/H). High R/H values correlated with a greater risk of MACE and all-cause mortality within a year. The study underscores the importance of BIVA-guided hydration therapy and R/H ratio in predicting CA-AKI in PCI patients with stable CAD. Incorporating R/H ratio assessments may enhance pre-procedural risk assessment and improve long-term outcomes (P = .0017).

Volume control strategy and patient survival in sepsis-associated acute kidney injury receiving continuous renal replacement therapy: a randomized controlled trial with secondary analysis.

Optimal strategy for volume control and the clinical implication of achieved volume control are unknown in patients with sepsis-associated acute kidney injury (AKI) receiving continuous renal replacement therapy (CRRT). This randomized controlled trial aimed to compare the survival according to conventional or bioelectrical impedance analysis (BIA)-guided volume control strategy in patients with sepsis-associated AKI receiving CRRT. We also compared patient survival according to achieved volume accumulation rate ([cumulative fluid balance during 3 days × 100]/fluid overload measured by BIA at enrollment) as a post-hoc analysis. We randomly assigned patients to conventional volume control strategy (n = 39) or to BIA-guided volume control strategy (n = 34). There were no differences in 28-day mortality (HR, 1.19; 95% CI, 0.63-2.23) or 90-day mortality (HR, 0.99; 95% CI 0.57-1.75) between conventional and BIA-guided volume control group. In the secondary analysis, achieved volume accumulation rate was significantly associated with patient survival. Compared with the achieved volume accumulation rate of ≤ - 50%, the HRs (95% CIs) for the risk of 90-day mortality were 1.21 (0.29-5.01), 0.55 (0.12-2.48), and 7.18 (1.58-32.51) in that of - 50-0%, 1-50%, and > 50%, respectively. Hence, BIA-guided volume control in patients with sepsis-associated AKI receiving CRRT did not improve patient outcomes. In the secondary analysis, achieved volume accumulation rate was associated with patient survival.

Fat-free mass predictive equation using multifrequency bioelectrical impedance data in adolescent soccer athletes: development and cross-validation.

OBJECTIVES: This study aimed to develop and cross-validate a fat-free mass (FFM) predictive equation using multifrequency bioelectrical impedance analysis (BIA) data in adolescent soccer athletes. METHODS: Male adolescent soccer athletes (n = 149; 13-19 y old) were randomly sorted using Excel and independently selected for development group (n = 100) or cross-validation group (n = 49). The FFM reference values were determined using dual-energy X-ray absorptiometry. Single-frequency BIA was used to plot tolerance ellipses. Multifrequency-BIA raw data were used as independent variables in regression models. Student's independent t-test was used to compare development and cross-validation groups. Stepwise multiple regression was used to develop the FFM predictive equation. Bland-Altman plots, Lin's concordance correlation coefficient, according to McBride criteria, precision, accuracy, and standard error of estimate (SEE) were calculated to evaluate the concordance and reliability of estimates. Bioelectrical impedance vector analysis was plotted to assess hydration status. RESULTS: No differences (P > 0.05) were observed between development and validation groups in chronological age, anthropometric data, bioelectrical impedance data, and FFM values obtained using dual-energy X-ray absorptiometry. Bioelectrical impedance vector analysis tolerance showed that all participants presented adequate hydration status compared to the reference population. The new FFM predictive equation developed and validated: FFM (kg) = -7.064 + 0.592 × chronological age (y) + 0.554 × weight (kg) + 0.365 × height²/resistance (cm²/Ω), presented R² = 0.95; SEE = 1.76 kg; concordance correlation coefficient = 0.95, accuracy = 0.98, and strength of concordance = 0.99. CONCLUSIONS: The present study developed and cross-validated an FFM predictive equation based on multifrequency bioelectrical data providing substantial FFM accuracy for male adolescent soccer athletes.