Multifrequency Bioelectrical Impedance Analysis Research Articles

Associations of body composition with physical activity, nutritional intake status, and chronotype among female university students in Japan

BackgroundHaving higher muscle mass in early adulthood is an important factor in preventing sarcopenia. However, university students undergo lifestyle changes compared to their high school years, which may lead to changes in body composition, such as an increase in body fat and a decrease in muscle mass. The study aimed to investigate the association between body composition and lifestyle behaviors, including chronotype, among Japanese female university students, due to the prevalence of underweight among young females in the country.MethodsThe physical activity level (PAL), daily dietary intake status, morningness-eveningness questionnaire (MEQ) score, and body composition of 230 students were assessed in this cross-sectional study. Body composition was measured using a multifrequency bioelectrical impedance analyzer, and body mass index (BMI), body fat percentage (%BF), and skeletal muscle mass index (SMI) were determined.ResultsIndividuals who were evening type (ET) had a higher %BF and lower SMI than those who were non-ET, but no differences in body weight or BMI were found. Although ET individuals had lower total energy intake, protein intake, and PALs than non-ETs, the differences were small. However, multiple regression analyses showed that SMI was significantly positively associated with MEQ and PAL, and %BF was significantly negatively associated with MEQ and PAL.ConclusionThese results suggest that female university students with lateness of chronotype and low physical activity have a body composition imbalance resulting in higher body fat and lower muscle mass. Therefore, young females may need to take chronotype-specific measures (especially ET individuals) to help them maintain an appropriate body composition.

Comparison between Discrete Multi-Wavelength Near-Infrared Spectroscopy and Bioelectrical Impedance Analysis in the Assessment of Muscle Mass for Community-Dwelling Older People.

(1) Background: This study evaluated the clinical implications of a new measurement technique for muscle mass using discrete multi-wavelength near-infrared spectroscopy (DMW-NIRS) compared with multifrequency bioelectrical impedance analysis (BIA) in older adults. (2) Methods: In a cross-sectional study involving 91 participants aged 65 years, the agreement of total lean mass for each measurement was assessed using the intraclass correlation coefficient (ICC) and Pearson's correlation analysis. The study was conducted at a university hospital from 10 July 2023 to 1 November 2023. (3) Results: A total of 45 men (mean age, 74.1) and 46 women (mean age, 73.6) were analyzed. In the comparisons of total lean mass between DMW-NIRS and BIA, ICC (2.1) was 0.943 and Cronbach's α coefficient was 0.949 (p < 0.001). Across all segments of lean mass, we found excellent agreement with the ICCs (>0.90) and acceptable values of the correlation coefficients (>0.6) between DMW-NIRS and BIA. (4) Conclusions: This study confirmed agreement in the measurements of muscle mass between portable devices using DMW-NIRS and BIA among community-dwelling older adults. A simple screening of muscle mass in a home setting would help to detect early decreases in muscle mass.

Blood Concentration of Macro- and Microelements in Women Who Are Overweight/Obesity and Their Associations with Serum Biochemistry.

Risk elements in blood matrices can affect human health status through associations with biomarkers at multiple levels. The aim of this study was to analyze 15 macro- and microelements in the blood serum of women with overweight (BMI of ≥25 kg/m2) and obesity (BMI of ≥30 kg/m2) and to examine possible associations with biochemical, liver enzymatic parameters, and markers of oxidative stress. Based on the power calculation, the study involved women (in the postmenopausal stage) with overweight (n = 26) and obesity (n = 22), aged between 50-65 years. Multifrequency bioelectrical impedance analysis was used to measure body composition parameters. Concentrations of elements were determined by inductively coupled plasma optical emission spectrometry, and Hg was measured using cold-vapor atomic absorption spectroscopy. Individuals with obesity, as indicated by a higher BMI, percentage of body fat, and visceral fat area, had elevated serum levels of Ca, Mg, Fe, Al, Sr, Pb, and Hg. Concentrations of Al, Cu, K, Sb, Zn, and Pb significantly affected biochemical and liver function markers in women with overweight or obesity. Elements such as Cu and Al were associated with increased total cholesterol. The correlation analysis between total antioxidant status and Cu, Al, and Ni confirmed associations in both groups. Our findings underscore the importance of addressing excess body weight and obesity in relation to risk elements. The results of the research could be beneficial in identifying potential targets for the treatment or prevention of comorbidities in people with obesity.

Body Composition Analyses in Older Adults May Vary Significantly Depending on the Bioelectrical Impedance Analyzer Modality

This study aimed to investigate the effects of aging on body composition analyses detected by a single-frequency (SF-BIA) and a multifrequency bioelectrical impedance analyzer (MF-BIA). Forty older patients and 42 young subjects were included in the study. Body composition was measured using an SF-BIA and an MF-BIA consecutively. Significant differences were found between the analyses of SF-BIA and MF-BIA in older patients. Handgrip strength values were found to correlate more strongly with the skeletal muscle mass index detected by MF-BIA. MF-BIA may be preferable to SF-BIA in older adults due to its higher correlation coefficient with handgrip strength.

Bioelectrical Impedance Phase Angle Value and Prolongations of PR and Corrected QT Intervals in Patients Undergoing Dialysis.

Phase angle value, derived from bioelectrical impedance analysis, represents the body cell mass and nutritional status of patients undergoing hemodialysis. Although phase angle value has clinical significance in these patients, its relationship with electrocardiogram (ECG), another clinically relevant bioelectrical examination, has not yet been well clarified. Two hundred and twenty-four patients undergoing dialysis (80 females and 144 males; mean ± SD, 72.2 ± 12.0 years old; 117 diabetic and 107 non-diabetic patients) were studied retrospectively. Multi-frequency bioelectrical impedance analysis was performed immediately after the end of dialysis therapy. The phase shift was geometrically converted into a phase angle value. The ECG was recorded simultaneously, and the upper limits of the PR interval, QRS width, and corrected QT interval (QTc) were set at 0.20, 0.12, and 0.44 sec, respectively. The geriatric nutritional risk index (GNRI), a representative nutritional index, was also determined. In addition, we examined the incidence of cardiac events, including heart failure, myocardial infarction, cardiac revascularization procedure, cardiac arrhythmia, and cardiac death, or all-cause death. Of 224 patients undergoing dialysis, the prolongation of the PR interval, QRS width, and QTc were found in 30.7, 17.4, and 62.1 %, respectively. The prevalence of QTc prolongation was higher in females and diabetic patients than in males and non-diabetic patients. An inverse relationship between phase angle value and QTc was observed only in males and non-diabetic patients. The relationships of GNRI both with phase angle value and QTc were stronger in males and non-diabetic patients. In addition, PR interval was inversely correlated with phase angle value only in non-diabetic patients. No significant correlation was found between phase angle value and QRS width. Five-year survival probability for the composite endpoints was significantly worse in patients with lower phase angle values. QTc prolongation was associated with survival in males and non-diabetic patients. Prolonged PR was associated with survival in non-diabetic patients. Relationships between phase angle value and ECG findings were demonstrated in patients undergoing dialysis, especially in males and non-diabetic patients. Although phase angle value has been considered as an index for evaluating nutritional status, another clinical application of phase angle value in predicting cardiac complications seems to be useful.

Serum afamin and its implications in adult growth hormone deficiency: a prospective GH-withdrawal study.

Adult growth hormone deficiency (AGHD) is associated with a high prevalence of metabolic syndrome (MS), which contributes to the unfavorable cardiovascular risk profile in these patients. Insulin like growth factor-1 (IGF-1) is a widely used biomarker, however it does not always reflect the cardiometabolic risk and has a poor relationship with clinical efficacy endpoints. Consequently, there is an unmet need for biomarkers to monitor responses to GH-replacement. Afamin is a hormone-like glycoprotein, expressed in the liver. Higher afamin levels are strongly associated with MS and insulin resistance (IR). Although both MS and IR are very common in AGHD, afamin has not been investigated in these patients. To investigate afamin as a potential biomarker in patients with AGHD. Participants included 20 AGHD patients (11 GH-substituted and 9 GH-unsubstituted) and 37 healthy controls. Subjects underwent routine laboratory examinations, anthropometric measurements, body composition analysis using multi-frequency bioelectrical impedance analysis (InBody720) and measurement of serum afamin concentrations. In GH-substituted subjects, GH-substitution was withdrawn for 2 months. Measurements were carried out right before GH-withdrawal, at the end of the 2-month withdrawal period, and 1 month after reinstituting GH-replacement therapy (GHRT). GH-unsubstituted patients demonstrated higher afamin levels compared to controls (p=0.03). Afamin positively correlated with skeletal muscle mass, bone mineral content, total body water, extracellular- and intracellular water content, insulin (all, p<0.01), HOMA-IR (p=0.01) and C-peptide (p=0.03) levels in AGHD but not in healthy controls. In GH-substituted patients 2-month of GH-withdrawal caused significant changes in body composition, including decreased fat-free mass, skeletal muscle mass, total body water, and intracellular water content (all, p<0.01); but these changes almost fully recovered 1 month after reinstituting GHRT. Unexpectedly, afamin levels decreased after GH-withdrawal (p=0.03) and increased with reinstitution (p<0.01). Changes of afamin levels during GH-withdrawal positively correlated with changes of HOMA-IR (r=0.80; p<0.01) and changes of insulin (r=0.71; p=0.02). Higher afamin levels in unsubstituted AGHD patients might indicate severe metabolic dysregulation. Significant changes accompanying GH-withdrawal and reinstitution, along with strong correlations with measures of IR, suggest that afamin could be a promising biomarker to monitor GHRT-associated changes of insulin sensitivity.

Estimation of the appendicular skeletal muscle mass and phase angle cut-off values from a young Turkish reference population using multifrequency bioelectrical impedance analysis.

Population-specific muscle mass cut-off values are recommended for the diagnosis of sarcopenia. In this study, we aimed to determine the appendicular muscle mass index (ASMI) and phase angle (PA) cut-off values for the Turkish population using multi-frequency bioelectrical impedance analysis (mBIA). A total of 250 healthy volunteers aged 18-40 years were included in the study between September 2020 and December 2021. PA was measured by mBIA, and appendicular skeletal muscle mass (ASM) was calculated by the Sergi formula using the resistance and reactance measurements from mBIA. ASMI was calculated as ASM (kg)/(height in meters)2. Two standard deviations (SD) below the mean values were accepted as cut-off points. 134 women and 116 men were included in the study (26.0±5.6 years). The ASMI cut-offs for men and women were 5.86 and 4.36 kg/m2, respectively. The PA cut-offs were 5.66° in men and 4.38° in women. The present study reported the ASMI and PA cut-off values specific to the Turkish population using the Sergi formula, which was suggested by the European Working Group on Sarcopenia in Older People (EWGSOP).

COMPARISON OF FOUR BODY COMPOSITION METHODS

BACKGROUND High-frequency (500Khz) direct segmental multifrequency bioelectrical impedance analysis (BIA) accurately calculates total water mass and body fat% (BF%), but it is unknown whether higher frequencies (1000Khz) increase measurement accuracy. PURPOSE: This study compared BIA 500Khz, BIA 1000Khz, the Department of Defense DoD Circumference Method (CM), and the reference standard DEXA. METHODS A total of 62 participants from the military healthcare system (n=25 males, 38.8±11.4yrs, n=37 females 43.7±15.95yrs) were measured. BF% was estimated via DEXA, BIA 500, BIA 1000, and CM to identify the relationship between methods using Pearson Correlation, Intraclass Correlation Coefficients, and Bland Altman Plots (p &amp;lt;.05). RESULTS CM BF% estimates displayed significant moderate correlations with BIA 500 (males r=.63, ICC=.76; females r=.77, ICC=.85), BIA 1000 (males r=.59, ICC=. 74; females r=.77, ICC=.85), and DEXA (males r=.62, ICC=.62; females r=.73, ICC=.82). BIA 500 BF% displayed significant strong correlations with BIA 1000 (males r=.99, ICC=.99; females r=.99, ICC=.99) and DEXA (males r=.93, ICC=.94; females r=.89, ICC=.89). Lastly, BIA 1000 BF% also showed a significant strong correlation DEXA (males r=.93, ICC=.94; females r=.84, ICC=.90). Evaluating proportional bias using a Bland-Altman analysis confirmed an overall mean bias of -1.72% (CM and DEXA) in the female group, indicating the tendency of DEXA to underestimate BF% compared to CM, limits of agreement from -14.24 to 10.8. There was an upward slope of .33 as the CM BF% decreased and the DEXA BF% increased. There was agreement of BF% to 32%, but after 32%, there was more dispersion from the mean and outliers and with a significant trend for a greater difference in BF% between CM and DEXA (p&amp;lt;.05). CONCLUSIONS The correlation was higher between BIA 500 and BIA 1000 to DEXA when compared to CM. There was proportional bias between DEXA and CM in the female group with CM underestimating BF% compared to DEXA.When compared to BIA methods, BF% estimated via CM methods do not correlate well with BF% from DEXA. However, it does not seem as though higher BIA frequencies better predict BF%. The views expressed in this abstract are those of the author(s) and do not necessarily reflect the official policy of the Department of Army, Navy, Defense, or any other agency of the U.S. Government, nor should any official endorsement be inferred by the Department of Defense, or the U.S. Government.

Co-Occurrence of Sarcopenia and Frailty in Acutely Admitted Older Medical Patients: Results from the Copenhagen PROTECT Study

BackgroundSarcopenia and frailty are often used interchangeably in clinical practice yet represent two distinct conditions and require different therapeutic approaches. The literature regarding the co-occurrence of both conditions in older patients is scarce as most studies have investigated the prevalence of sarcopenia and frailty separately.ObjectivesWe aim to evaluate the prevalence and co-occurrence of sarcopenia and frailty in a large sample of acutely admitted older medical patients.DesignSecondary analyses using cross-sectional data from the Copenhagen PROTECT study.SettingPatients were included from the acute medical ward at Copenhagen University Hospital, Bispebjerg and Frederiksberg, Copenhagen, Denmark, between November 2019 and November 2021.ParticipantsAcutely admitted older medical patients (≥65 years).MeasurementsHandgrip strength (HGS) was investigated using a handheld dynamometer. Lean mass (SMI) was investigated using direct-segmental multifrequency bioelectrical impedance analyses (DSM-BIA). Low HGS, low SMI, and sarcopenia were defined according to the recent definitions from the European Working Group on Sarcopenia in Older People (EWGSOP2). The Clinical Frailty Scale (CFS) was used to evaluate frailty, with a value > 5 indicating the presence of frailty. Patients were enrolled and tested within 24 hours of admission.ResultsThis study included 638 patients (mean age: 78.2±7.6, 55% female) with complete records of SMI, HGS, and the CFS. The prevalence of low HGS, low SMI, sarcopenia, and frailty were 39.0%, 33.1%, 19.7%, and 39.0%, respectively. Sarcopenia and frailty co-occurred in 12.1% of the patients.ConclusionsIt is well-known that sarcopenia and frailty represent clinical manifestations of ageing and overlap in terms of the impairment in physical function observed in both conditions. Our results demonstrate that sarcopenia and frailty do not necessarily co-occur within the older acutely admitted patient, highlighting the need for separate assessments of frailty and sarcopenia to ensure the accurate characterization of the health status of older patients.

Phase angle of bioelectrical impedance analysis as an indicator for diabetic polyneuropathy in type 2 diabetes mellitus.

Due to the heterogenous clinical symptoms and deficits, the diagnosis of diabetic polyneuropathy (DPN) is still difficult in clinical routine leading to increased morbidity and mortality. We studied the correlation of phase angle (PhA) of bioelectrical impedance analysis (BIA) with clinical, laboratory and physical markers of DPN to evaluate PhA as possible diagnostic method for DPN. In this cross-sectional observational study as part of the Heidelberg Study on Diabetes and Complications we examined 104 healthy individuals and 205 patients with type 2 diabetes mellitus (T2D), amongst which 63 had DPN. The PhA was calculated from multi-frequency BIA. Nerve conduction studies (NCS), quantitative sensory testing (QST) and diffusion-weighted magnetic resonance neurography (MRN) to determine fractional anisotropy (FA) reflecting peripheral nerve integrity were performed. T2D patients with DPN had lower PhA values (5.71 ± 0.10) compared to T2D patients without DPN (6.07 ± 0.08, p = 0.007,  + 6.1%) and healthy controls (6.18 ± 0.08, p < 0.001,  + 7.9%). Confounder-adjusted analyses showed correlations of the PhA with conduction velocities and amplitudes of the peroneal (β=0.28; β=0.31, p < 0.001) and tibial nerves (β=0.28; β=0.32, p < 0.001), Z-scores of QST (thermal detection β=0.30, p < 0.05) and the FA (β=0.60, p < 0.001). ROC analysis showed similar performance of PhA in comparison to mentioned diagnostic methods. The study shows that PhA is in comparison to other test systems used, at least an equally good and much easier to handle, investigator independent marker for detection of DPN.

The choice of diagnostic modality influences the proportion of low muscle strength, low muscle mass, and sarcopenia in colorectal cancer patients

Low muscle strength, low muscle mass, and sarcopenia have a negative impact on health outcomes in colorectal cancer (CRC) patients. Different diagnostic modalities are used to identify these conditions but it is unknown how well the modalities agree. The aim of this study was to compare different diagnostic modalities by means of calculating the proportion of low muscle strength, low muscle mass, and sarcopenia in CRC patients, and to investigate the agreement for sarcopenia between the various modalities. Men and women participating in the Norwegian Dietary Guidelines and colorectal cancer Survival (CRC-NORDIET) study were included in the analyses. Cut-off values for low muscle strength, low muscle mass, and sarcopenia were defined according to the second consensus set by the European Working Group on Sarcopenia in Older People (EWGSOP2). The diagnostic modalities used to assess muscle strength were handgrip strength and the sit-to-stand test. For muscle mass, computed tomography, dual-energy X-ray absorptiometry (DXA), multi-frequency bioelectrical impedance analysis (MF-BIA), and single-frequency BIA (SF-BIA) were applied. Cohen's kappa was calculated to determine the agreement for low muscle strength and confirmed sarcopenia between diagnostic modalities. Five hundred and three men and women (54% men, mean age of 66 (range 50-80) years old) were included in the analysis. As much as 99% (n=70) of the population was identified with low muscle mass by MF-BIA, while the other modalities identified 9-49% as having low muscle mass. Handgrip strength identified a lower proportion of low muscle strength as compared with the sit-to-stand test (4% vs. 8%). When applying various combinations of diagnostic modalities for low muscle strength and low muscle mass, the proportion of sarcopenia was found to be between 0.3 and 11.4%. There was relatively poor agreement between the different diagnostic modalities with Cohen's Kappa ranging from 0.0 to 0.55, except for the agreement between SF-BIASergi and MF-BIASergi, which was 1. The proportion of low muscle strength, low muscle mass, and sarcopenia in CRC patients varied considerably depending on the diagnostic modalities used. Further studies are needed to provide modality-specific cut-off values, adjusted to sex, age and body size.

Effect of body fat mass loss on prognosis of radical resection for pancreatic ductal adenocarcinoma based on bioelectrical impedance analysis

BackgroundFew reports have performed a prognostic analysis based on bioelectrical impedance analysis in patients with radical resection of pancreatic ductal adenocarcinoma (PDAC), and its usefulness in prognostic analysis remains unclear. This study aimed to evaluate body composition changes in patients undergoing radical resection for PDAC and analyze its impact on prognosis.MethodsThe medical records of radical resection for patients with PDAC were retrospectively reviewed, and the parameters of body composition, including body weight, skeletal muscle mass, body fat mass (BFM), and extracellular water-total body water ratio, from preoperatively to 12 months postoperatively, for each surgical procedure were measured based on direct segmental multifrequency bioelectrical impedance analysis with an InBody 770 (InBody Inc., Tokyo, Japan) device. The clinicopathological and prognostic factors were analyzed.ResultsAmong 79 patients who underwent radical resection for PDAC, 36 (46%), 7 (8%), and 36 (46%) underwent pancreatoduodenectomy, total pancreatectomy, and distal pancreatectomy, respectively. The multivariate overall survival analysis demonstrated that BFM loss percentage at 1 month postoperatively ≧14% (p = 0.021), lymph node metastasis (p = 0.014), and non-adjuvant chemotherapy (p <  0.001) were independent poor prognostic factors. Multivariate analysis revealed that preoperative BFM < 12 kg and preoperative albumin < 3.5 g/dL were independently associated with BFM loss percentage at 1 month postoperatively ≧14% (p = 0.021 and p = 0.047, respectively).ConclusionsLoss of BFM in the early postoperative period may have a poor prognosis in radical resection of PDAC.

Exploring the Relationship between Physical Activity and Segmental Body Composition Parameters in Office Workers: A Multi-Frequency Bioelectrical Impedance Analysis Approach

This research aimed to determine the relationship between physical activity levels and body composition parameters in office workers. The study was carried out with 60 individuals who agreed to participate in the study and met the inclusion criteria, among the office workers who had sedentary jobs, at the Rector's Office of a university in the Eastern Region of the Republic of Turkey between June 2021 and January 2022. Informed Voluntary Consent Forms and the International Physical Activity Questionnaire were administered to participants. Body compositions were measured with the TANITA MC-780 Bioelectrical impedance device. The study found a positive relationship between lean body mass (kg), muscle mass in the right leg (kg), muscle mass in the left leg (kg), muscle mass in the right arm (kg), muscle mass in the left arm (kg), and trunk muscle (kg) with all Phase Angle (PhA) measures (p&amp;lt;0.05). Moreover, the study determined a correlation between lean mass in the right leg (kg), lean mass in the left leg (kg), lean mass in the right arm (kg), and lean mass in the left arm (kg) with vigorous activity scores (p&amp;lt;0.05). The study's results add to the existing literature on segmental body composition values in individuals with prolonged sedentary behavior.

Evaluation of Multi-Frequency Bioelectrical Impedance Analysis against Dual-Energy X-ray Absorptiometry for Estimation of Low Muscle Mass in Older Hospitalized Patients.

The accuracy of multi-frequency (MF) bioelectrical impedance analysis (BIA) to estimate low muscle mass in older hospitalized patients remains unclear. This study aimed to describe the ability of MF-BIA to identify low muscle mass as proposed by The Global Leadership Initiative on Malnutrition (GLIM) and The European Working Group on Sarcopenia in Older People (EWGSOP-2) and examine the association between muscle mass, dehydration, malnutrition, and poor appetite in older hospitalized patients. In this prospective exploratory cohort study, low muscle mass was estimated with MF-BIA against dual-energy X-ray absorptiometry (DXA) in 42 older hospitalized adults (≥65 years). The primary variable for muscle mass was appendicular skeletal muscle mass (ASM), and secondary variables were appendicular skeletal muscle mass index (ASMI) and fat-free mass index (FFMI). Cut-off values for low muscle mass were based on recommendations by GLIM and EWGSOP-2. MF-BIA was evaluated against DXA on the ability to estimate absolute values of muscle mass by mean bias, limits of agreement (LOA), and accuracy (5% and 10% levels). Agreement between MF-BIA and DXA to identify low muscle mass was evaluated with sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV). The association between muscle mass, dehydration, malnutrition, and poor appetite was visually examined with boxplots. MF-BIA overestimated absolute values of ASM with a mean bias of 0.63 kg (CI: -0.20:1.46, LOA: -4.61:5.87). Agreement between MF-BIA and DXA measures of ASM showed a sensitivity of 86%, specificity of 94%, PPV of 75% and NPV of 97%. Boxplots indicate that ASM is lower in patients with malnutrition. This was not observed in patients with poor appetite. We observed a tendency toward higher ASM in patients with dehydration. Estimation of absolute ASM values with MF-BIA should be interpreted with caution, but MF-BIA might identify low muscle mass in older hospitalized patients.

Association between fat-free mass and survival in critically ill patients with COVID-19: A prospective cohort study.

Most critically ill patients with COVID-19 experience malnutrition and weight loss associated with negative clinical outcomes. Our primary aim was to assess body composition during acute and late phase of illness in these patients in relation to clinical outcome and secondary to tailored nutrition support. This prospective cohort study included adult critically ill patients with COVID-19. Body composition (fat-free mass [FFM] [exposure of interest], fat mass [FM], skeletal muscle mass [SMM], and phase angle [PA]) was determined with multifrequency bioelectrical impedance analyses in the acute and late phase. Nutrition support data were collected simultaneously. Clinical outcome was defined as intensive care unit (ICU) survival (primary outcome) and 30-90 days thereafter, duration of mechanical ventilation, and length of ICU stay and length of hospital stay (LOS). Nonparametric tests and regression analyses were performed. We included 70 patients (73% male, median age 60 years). Upon admission, median BMI was 30 kg/m2 , 54% had obesity (BMI > 30 kg/m2 ). Median weight change during ICU stay was -3 kg: +3 kg FM and -6 kg FFM (-4 kg SMM). Body composition changed significantly (P < 0.001). Regarding clinical outcome, only low PA was associated with prolonged LOS (odds ratio = 0.83, 95% CI = 0.72-0.96; P = 0.015). Patients with optimal protein intake (>80%) during acute phase maintained significantly more FFM (2.7 kg, P = 0.047) in the late phase compared with patients who received <80%. FFM decreased significantly during acute and late phase of illness, but we observed no association with ICU survival. Only low PA was associated with prolonged LOS. FFM wasting likely occurred because of disease severity and immobility.

Sedentary Behavior and Phase Angle: An Objective Assessment in Physically Active and Inactive Older Adults.

The purpose of the present study was to investigate the associations of the objectively assessed total sedentary behavior (SB) amount and SB patterns with phase angle (PhA) in older populations and to conduct a comparison analysis for those who are physically active (meet 150 min/week) and inactive (less than 150 min/week). During May to August 2023, a convenience sampling was used to recruit older adults (aged ≥ 65 years) living in a community in Taiwan. The total SB amount (minutes/day), SB patterns (including SB bouts and breaks), and physical activity were assessed by a triaxial accelerometer. A multifrequency bioelectrical impedance analyzer (BIA) was used to measure PhA. Multiple linear regression analysis was employed to examine the associations between SB and PhA in the total number of participants and stratified in the physically active and inactive groups. For the whole sample (n = 166; mean age: 72.1 ± 5.5 years), the total SB amount and patterns of SB were not associated with PhA. For those physically active, the total SB amount and SB patterns were not associated with PhA. Among those physically inactive, the total SB amount was negatively related to PhA (B: -0.059, 95% CI: -0.118, 0.000). This study underscores the importance of minimizing the total SB amount in physically inactive older adults, providing evidence for future interventions targeting SB and PhA in this population.

EXAMINING THE ASSOCIATION BETWEEN HYDRATION STATUS AND OBESITY IN OLDER ADULTS

Abstract Adequate hydration is an important modifiable determinant of overall physical health within community-dwelling older adults. Research and clinical practice often use urine osmolarity and bioelectrical impedance analysis (BIA) to assess hydration status. Prior evidence links inadequate hydration to increased obesity, typically measured by body mass index (BMI). However, this association has not yet been evidenced in community-dwelling older adults, especially in low-income settings. This cross-sectional study assessed 103 older adults (16 men, 87 women; mean age 75.7 ± 7.19 years; BMI 26.8 ± 5.22 kg/m2). Total body water (TBW), intracellular water (ICW), fat mass (FM) and fat-free mass (FFM) were measured using multi-frequency BIA (InBody S10). Linear regression analysis examined continuous BMI. TBW/FFM and ICW/FFM as hydration indicators showed weak correlation with FM (TBW/FFM: r = 0.357, p &amp;lt; 0.001; ICW/FFM: r = -0.243, p = 0.013). However, only TBW/FFM significantly correlated with BMI (TBW/FFM: r = 0.236, p = 0.016; ICW/FFM: r = -0.143, p = 0.151). These results suggest TBW/FFM and ICW/FFM may not adequately indicate hydration status while maintaining sensitivity to body composition in adults aged 60-96 years. Further research should examine these findings using urine osmolarity as the hydration assessment.

A Prospective Observational Study Evaluating Extracellular Water to Total Body Water Ratio By Using the Bioelectrical Impedance Analysis in Elderly Patients with Hematologic Malignancies

[Introduction] Body composition assessment is often used in clinical practice for evaluating and monitoring sarcopenia and nutritional status. Bioelectrical impedance analysis (BIA), which uses the conductivity of the body's intracellular and extracellular fluids to respond to cell and tissue functions, has gradually become widely used in clinical practice because of its non-invasiveness, convenience, and low cost. The ratio of extracellular water to total body water (ECW/TBW) measured by BIA has been found to be related to the prognosis of many diseases, but its application value for patients with hematologic malignancies still needs to be further explored. The purpose of this study was to further explore the application value of ECW/TBW measured by BIA in elderly patients with hematologic malignancies. [Patients and Methods] We prospectively analyzed 82 elderly patients aged≥60 years with hematologic malignancies diagnosed at our institution between 2015 and 2018. Appendicular skeletal muscle mass (ASM) and ECW/TBW ratio were measured by using multifrequency BIA (InBody 720). In this study, the ECW/TBW cut off value to predict survival was determined by a receiver operating characteristic (ROC) curve analysis. The ECW/TBW ratio cut offs was 0.397 (sensitivity 67.3% and specificity 54.5%, area under the curve (AUC) 0.586, [95% confidence interval (CI) 0.46-0.711]) for all 82 patients. Patients with ECW/TBW &amp;lt; 0.397 were sorted into the non-overhydrated group (NOH-group) and those with ECW/TBW &amp;gt; 0.397 into the overhydrated group (OH-group). Skeletal muscle index (SMI) was defined as the ratio of ASM divided by height in square centimeters. Sarcopenia was defined according to the AWGS2019 algorithm, in which the patient has low muscle mass, and low muscle strength or low physical performance. The study protocol was approved by the Institutional Review Board of Yokohama Municipal Citizen's Hospital, and it was carried out in accordance with the Declaration of Helsinki. This trial was registered in the UMIN clinical trial registry (UMIN000035834). [Results] Median age at diagnosis was 78 years (60-93 years), with 46 males and 36 females. The diagnosis included non-Hodgkin lymphoma (NHL, n=51), multiple myeloma (MM, n=11), myelodysplastic syndrome (MDS, n=12), and acute myeloid leukemia (AML, n=8). The mean ECW/TBW ratio of all 82 patients was 0.397±0.014. There was no significant difference in the mean ECW/TBW ratio between disease types. Thirty-four patients (41%) were classified as OH-group and 48 patients (59%) were classified as NOH-group. The median age in the OH- and NOH- groups was 83 and 74 years (p&amp;lt;0.001). The mean BMI did not differ between the two groups (22.17 vs. 22.16 kg/m2, respectively, p = 0.99). The prevalence of sarcopenia was 41.4% (34/82). There was no significant difference in overall survival (OS) between the sarcopenia and the non-sarcopenia group (3-year OS, 58.1% vs. 63.3%, p=0.96). On the other hand, patients with OH-group had shorter OS than those with NOH-group (3-year OS, 46.8% vs. 70.5%, p=0.03). We next performed a subgroup analysis of NHL patients. Among 51 NHL patients, 30 (59%) had aggressive lymphoma and 21 (41%) had indolent lymphoma. Twenty patients (39%) were classified as OH-group and 31 patients (61%) were classified as NOH-group. Patients with OH-group had shorter OS than those with NOH-group (3-year OS, 67.1% vs. 90.3%, p=0.02). The prevalence of sarcopenia was 37.3% (19/51) and sarcopenia was not correlated with survival in NHL patients. Among 30 aggressive lymphoma patients, the overhydrated status was closely associated with poor outcome (3-year OS was 57.1% in the OH-group and 88.9% in the NOH-group, p=0.01). On the other hand, there was no significant difference in OS between the OH- and NOH- groups among 21 indolent lymphoma patients. Multivariate analysis showed that the overhydrated status (high-ECW/TBW ratio) was an independent prognostic factor for OS in patients with aggressive lymphoma (HR, 5.30; 95%CI, 1.01-27.7, p=0.04). [Conclusion] The present study demonstrated that high-ECW/TBW ratio was associated with poor outcome in elderly patients with hematologic malignancies. Especially, the overhydrated status was closely associated with poor outcome in elderly aggressive lymphoma patients. Since our results are based on a small-sized analysis, further large prospective studies are warranted to verify this conclusion.

An analytical investigation of body parts more susceptible to aging and composition changes using statistical hypothesis testing

In recent years, age-related changes in body composition in the elderly are attracting attention. This is associated with a decline in physical functions and an increased risk of disease development. In general, age-related changes in body composition can be minimized with appropriate exercise. However, there are no studies that investigate body parts susceptibility to aging and changes in body composition of those parts. Therefore, devising exercise programs and advising daily life while taking these into account becomes difficult. This study aims to identify body parts that are more susceptible to aging and their body composition changes. The body composition was obtained with a Direct Segmental Multi-frequency Bioelectrical Impedance Analysis using InBody770 in 8 male elderly patients who had been shortly hospitalized. Statistical hypothesis testing was used to determine whether site-specific body composition changed significantly between hospital discharge and 1 year, 1 year and 2 years, and hospital discharge and 2 years. The results showed that Lean body mass, Total Body Water, Intracellular Water, Extracellular Water in the right arm; Lean body mass and Total Body Water in the left arm and trunk are more sensitive to aging.

Effect of peritoneal dialysate on bioelectrical impedance analysis variability in pediatric patients receiving peritoneal dialysis.

Previous adult studies have yielded conflicting results regarding whether the presence (D +) or absence (D-) of peritoneal dialysate affects the accuracy of bioelectrical impedance analysis (BIA) measurements. The aim of this study was to investigate whether the accuracy of BIA data varies between D + and D- measurements in children. This cross-sectional study recruited chronic kidney disease stage 5 patients aged 3 to 18years who received peritoneal dialysis. Body composition was assessed by multifrequency BIA, and values were compared between D + and D- measurements using the intraclass correlation coefficient (ICC). Fifty paired BIA measurements were collected from 18 patients with a mean age of 13.6 ± 4.1years and a mean dialysate fill volume of 1,006 ± 239.7ml/m2. Sixteen out of 17 BIA parameters (94.1%) exhibited excellent correlations between D + and D- measurements (ICC values = 0.954, 0.998). There was a trend of increased fluid status, including extracellular water, edema index, and overhydration, in D + measurements, with mean differences (95% CIs) of 0.5 (0.4, 0.6) L, 0.002 (0.001, 0.002), and 0.1 (0.1, 0.2) L, respectively. Soft lean mass and fat-free mass were higher in D + measurements, with mean differences (95% CIs) of 1.4 (1.2, 1.6), and 1.6 (1.4, 1.8) kg, respectively. In addition, patients older than 10years had a stronger correlation between D + and D- measurements than younger patients. A total of 94.1% of BIA parameters exhibited excellent correlations between D + and D- measurements, especially patients older than 10years. We recommend that BIA measurements be collected from children regardless of the presence of peritoneal dialysate.