Distribution of Bioelectrical Impedance Vector Analysis and Phase Angle in Korean Elderly and Sarcopenia

The usefulness of the updated bioelectrical impedance vector analysis references for assessing malnutrition, sarcopenia and predicting mortality in hospitalized patients

BACKGROUND & AIMS

The application of validated pre-screening tools is crucial in clinical practice to identify patients at risk for disease. Bioelectrical Impedance Vector Analysis (BIVA) has gained recognition as a qualitative method for monitoring body composition and assessing the health status of hospitalized patients. This study investigates the utility of updated BIVA reference standards in evaluating malnutrition, sarcopenia, and mortality among hospitalized individuals.

MATERIAL AND METHOD

This retrospective observational study included 2.872 patients admitted to Quironsalud Málaga Hospital between January 2019 and January 2024. Malnutrition and sarcopenia were diagnosed using the Global Leadership Initiative on Malnutrition (GLIM) and the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) guidelines. Mortality was defined as death within one year of their initial discharge or later admissions. BIVA was performed using the former and the new 50th, 75th, and 95th reference tolerance ellipses of general population.

RESULTS

BIVA revealed significant differences in bioimpedance vectors between malnourished (n = 1187, 544 women) and non-malnourished patients, sarcopenic (n = 136, 51 women) and non-sarcopenic patients, and non-survivors (n = 317, 160 women) compared to survivors. When previous BIVA references (Piccoli 1995) were applied, the bioimpedance vectors for malnourished, sarcopenic, and non-surviving patients fell within the 75th tolerance ellipses. However, with updated references, these vectors shifted rightward, moving outside the 75th and 95th tolerance ellipses. Univariate Cox analysis showed that participants with vectors outside the new 95th tolerance ellipses faced significantly higher mortality risk (HR = 6.22 [95 % CI 4.40-8.80], p < 0.001) and lower survival rates (log-rank test p < 0.001) compared to those within the 75th ellipses. These trends persisted even after adjusting for age, sex, and BMI (HR = 4.79 [95 % CI 3.29-6.97], p < 0.001). The new reference ellipses demonstrated greater prognostic accuracy compared to the older ones, emphasizing their value in identifying high-risk patients.

CONCLUSION

The implementation of BIVA with newly established reference tolerance ellipses significantly enhances the evaluation of body composition and overall health in hospitalized patients. These updated tolerance ellipses are instrumental in accurately identifying malnutrition, sarcopenia, and heightened mortality risks. The delineation of specific mortality risk zones underscores the potential of incorporating these advanced BIVA ellipses into routine pre-screening protocols, thereby optimizing clinical nutritional assessments and interventions.

The implications of bioelectrical impedance vector analysis in older adults with hip fractures

OBJECTIVES

This study used bioelectrical impedance vector analysis to assess body composition in older adults with hip fractures, comparing results with reference populations.

STUDY DESIGN

This cross-sectional study included patients aged 65 years or more who had undergone surgery for hip fracture and baseline bioelectrical impedance analysis at 50 kHz. Using raw impedance data, bioelectrical impedance vector analysis was conducted, calculating phase angle and analyzing resistance (R) and reactance (Xc) relative to height (R/H and Xc/H) on RXc graphs.

MAIN OUTCOME MEASURES

Men and women were compared with reference populations using confidence ellipses. Individual vectors were plotted against 50 %, 75 %, and 95 % tolerance ellipses and compared with international references matched for age and body mass index and a young adult group, further differentiated by sarcopenia status.

RESULTS

Among 103 patients with hip fracture (24 men, 79 women), confidence ellipses showed significant differences from reference populations (P < 0.001), with reduced Xc and lower phase angle (men: 4.3 ± 1.5°; women: 3.8 ± 1.0°), consistent with higher R/H and lower Xc/H. Most vectors lay outside the 75 % and 95 % tolerance ellipses, primarily in the lower-right and upper-right quadrants, indicating body cell mass loss and water imbalance. Only 8.3 % of men and 12.7 % of women fell within the 75 % tolerance ellipse of community-dwelling older adults. Sarcopenic patients showed greater rightward displacement, indicating more severe muscle wasting and dehydration.

CONCLUSIONS

Older hip fracture patients showed a distinct pattern on bioelectrical impedance vector analysis indicating frailty and malnutrition. Bioelectrical impedance vector analysis may effectively screen for body composition changes and nutritional status, supporting timely, multidisciplinary interventions.

Usefulness of body composition assessment by bioelectrical impedance vector analysis in subacute post-stroke patients in rehabilitation

Bioelectrical Impedance Vector Analysis (BIVA) is a valuable tool for evaluating hydration and body composition, but its application in subacute post-stroke patients remains unexplored. This study aimed to fill this gap by analyzing BIVA in a cohort of 87 subacute post-stroke patients (42 women, mean age 69 ± 12) undergoing rehabilitation. At admission (T0), diagnosis of malnutrition with GLIM criteria and of sarcopenia with EWGSOP2 was done, and patients were analyzed with BIVA. The change in modified Barthel Index (mBIT1-mBIT0) was assessed to evaluate the improvement in functional recovery. BIVA revealed that both adult patients (< 65 years, n = 29) and elderly patients (≥ 65 years, n = 58) exhibited high body fluid overload and low muscle mass. Additionally, BIVA revealed a significant rightward shift of the bioimpedance vectors in malnourished (n = 37) versus non-malnourished patients (T2 = 56.9, p < 0.001, D = 1.68) and in sarcopenic (n = 24) versus non-sarcopenic patients (T2 = 36.4, p < 0.001, D = 1.5). Lastly, the BIVA distinguished patients with greater improvement (n = 53) from patients with lower improvement (n = 34) (T2 = 10.6, p = 0.007, D = 0.7). In conclusion, BIVA is an effective, easy-to-use tool for evaluating hydration, nutritional status, and recovery in post-stroke rehabilitation.

Age-related changes in bioelectrical impedance analysis-derived phase angle (PhA) and the association between PhA and sarcopenic obesity in Chinese adults

There are limited studies on the phase angle (PhA) and sarcopenic obesity (SO) in the Chinese population. This study aimed to establish 50 kHz-PhA reference data for SO population, and to evaluate the correlation between 50 kHz-PhA and SO. A total of 10,312 participants including 5415 men and 4897 women were enrolled in this study, and their resistance and reactance at 50 kHz, and body composition parameters were measured a segmental multifrequency bioelectrical impedance analysis device (InBody 720). Participants were compared between the SO and non-SO groups. Then, age and fat parameters related changes in PhA were evaluated. Furthermore, Receiver Operating Characteristic (ROC) curves were used to identify the optimal PhA cutoff values for detecting SO in males and females. The results showed significant differences in PhA and body composition parameters between the SO group and the non-SO group in both sexes (P < .001), and the prevalence rates of SO increase with age in both sexes (P < .001). The PhA values decrease with age, with a significant decrease beginning at age 65 years for males and 66 years for females. The accumulation of excess adipose tissue was also found to be associated with decrease in 50 kHz-PhA value. Furthermore, PhA was negatively associated with SO, independent of age and sex. The area under the ROC curve (AUC) of PhA for SO was 0.790 (95% CI: 0.746-0.833, P < .001) in males and 0.763 (95% CI: 0.702-0.825, P < .001) in females. The optimal cutoff value was ≤ 5.55° (specificity 0.693, sensitivity 0.759) for males and ≤4.79° (specificity 0.687, sensitivity 0.738) for females. In conclusion, 50 kHz-PhA can be used as a predictor of SO, with cutoff values of ≤5.55° for males and ≤4.79° for females. This simple and practical method of using 50 kHz-PhA to predict SO could be valuable in clinical practice.

Exploring the Impact of Sarcopenia on Mortality in Breast Cancer Patients: A Comprehensive Systematic Review and Meta-Analysis

Background

This study assesses the frequency of sarcopenia in patients with breast cancer (BC) and its association with mortality rates.

Methods

An all-encompassing search across (PubMed, Scopus, Web of Science, and CINAHL) was done, to identify studies, published until August 2023, that report data on sarcopenia and mortality in BC patients. A meta-analysis was then done using a random-effects model.

Results

Out of 989 initially identified potential studies, 19 met inclusion criteria. Analysis of 15 studies showed a rate of sarcopenia of 38% (95% CI: 29-48%), with moderate heterogeneity (I 2 = 25.8%). Sarcopenia was linked to increased mortality risk in BC patients across 16 studies (HR: 1.77, CI: 1.35-2.32, p = <0.001) with both shorter and longer follow-up periods. Similarly, mortality risks were significantly higher in metastatic (HR: 1.52, CI: 1.14-2.03, p = 0.004) and non-metastatic (HR: 2.55, CI: 1.66-3.93, p < 0.001) BC patients with sarcopenia.

Conclusion

Our analysis demonstrates a substantial prevalence of sarcopenia in BC patients. Importantly, sarcopenia was significantly linked to an elevated risk of mortality in this population. Subgroup analyses, stratified by follow-up periods and disease stage, consistently reveal increased mortality risks associated with sarcopenia, underscoring its clinical relevance in both short- and long-term patient outcomes. Our findings further strengthen the need to recognize and address sarcopenia as a critical factor in BC management and prognosis.

Handgrip Strength in Health Applications: A Review of the Measurement Methodologies and Influencing Factors

This narrative review provides a comprehensive analysis of the several methods and technologies employed to measure handgrip strength (HGS), a significant indicator of neuromuscular strength and overall health. The document evaluates a range of devices, from traditional dynamometers to innovative sensor-based systems, and assesses their effectiveness and application in different demographic groups. Special attention is given to the methodological aspects of HGS estimation, including the influence of device design and measurement protocols. Endogenous factors such as hand dominance and size, body mass, age and gender, as well as exogenous factors including circadian influences and psychological factors, are examined. The review identifies significant variations in the implementation of HGS measurements and interpretation of the resultant data, emphasizing the need for careful consideration of these factors when using HGS as a diagnostic or research tool. It highlights the necessity of standardizing measurement protocols to establish universal guidelines that enhance the comparability and consistency of HGS assessments across various settings and populations.

Specific bioelectrical vectors pattern in individuals with sarcopenic obesity

BACKGROUND

Sarcopenic obesity is a common condition in the elderly associated with excessive adiposity and low muscle mass and strength.

AIMS

This study aims to establish a method for detecting bioelectrical characteristics in individuals with sarcopenic obesity through specific Bioelectrical Impedance Vector Analysis (specific BIVA), while considering the characteristics of individuals with healthy, sarcopenic, and obese conditions.

METHODS

The sample was composed by 915 Italian adults over 50 years of age (men: 74.6 ± 8.8 y; women:76.3 ± 8.8 y) living in Sardinia (Italy). A dataset of 1590 US adults aged 21 - 49 years retrieved from the 2003 - 2004 National Health and Nutrition Examination Survey was also considered in a final step of the study. Anthropometric (stature, weight, waist, arm, and calf circumferences) and whole-body bioelectrical variables were taken. In the Italian sample, bioelectrical impedance was applied to estimate the relative content of fat mass and skeletal muscle mass. Groups with healthy body composition (NS-NO), or consistent with sarcopenia (S), sarcopenic obesity (S-O), and obesity (O) were defined based on the cut-offs suggested by European expert guidelines (EWGSOP2 and ESPEN-EASO). Specific BIVA was applied to compare groups and to identify the area for sarcopenic obesity within young-adults tolerance ellipses. The position of the specific vector of US individuals with S-O, selected on the basis of DXA measurements, was also considered.

RESULTS

In both sexes of the Italian sample, the bioelectrical characteristics of the four groups were different (p < 0.001). The differences were mainly related to vector length, indicative of higher fat mass, which was longer in the O and S-O groups, and phase angle, a proxy of intracellular/extracellular water and muscle mass, lower in the sarcopenic groups. Bioelectrical vectors of the S-O group fell in the right quadrant, outside of the 95 % tolerance ellipses of young adults. The mean vector of the US sample with S-O fell in the same area. Within the S-O area, women had similar bioelectrical values, while men showed phase angle variability, which was related to the severity of the condition.

CONCLUSIONS

Specific BIVA detects body composition peculiarities of individuals with sarcopenic obesity, thus allowing their diagnosis when associated with low handgrip strength values.

Phase Angle and Bioelectrical Impedance Vector Analysis (BIVA) in Amyotrophic Lateral Sclerosis (ALS) Patients

Phase angle (PhA) and bioelectrical impedance vector analysis (BIVA) have emerged as valuable tools for assessing nutritional status and prognosis in various patient populations, but there is a lack of studies in rare neurodegenerative diseases. The purpose of this cross-sectional study was to investigate these bioelectrical parameters in patients with amyotrophic lateral sclerosis (ALS), compared with healthy peers. The tetrapolar impedance method was applied and bioimpedance analysis (BIA) was performed. Bioelectrical parameters were obtained (Resistance—R; Reactance—Xc) or calculated (PhA; BIVA). For BIVA, bivariate vectors and confidence ellipses were graphically represented. In addition, R and Xc were used to determine body composition (BC) (Fat Mass—FM; Fat-Free Mass—FFM; and Total Body Water—TBW). In this study, 40 participants were divided into two groups: case group (n = 20, ALS patients) and control group (n = 20, healthy subjects. Our main results showed that ALS patients presented low levels of BMI, FFM, R, and Xc adjusted by height (R/H, Xc/H), hydration, and cellularity, compared to the healthy subjects. Our findings highlight BC and bioelectrical parameters, including PhA and BIVA, as valuable indicators of nutrition status, which should be implemented in the nutrition care process of ALS patients during the disease course.

Diagnostic Criteria and Measurement Techniques of Sarcopenia: A Critical Evaluation of the Up-to-Date Evidence

Sarcopenia, a geriatric syndrome characterized by progressive skeletal muscle mass and function decline, poses a significant health risk among the elderly, contributing to frailty, falls, hospitalization, loss of independence and mortality. The prevalence of sarcopenia varies significantly based on various factors, such as living status, demographics, measurement techniques and diagnostic criteria. Although the overall prevalence is reported at 10% in individuals aged 60 and above, disparities exist across settings, with higher rates in nursing homes and hospitals. Additionally, the differences in prevalence between Asian and non-Asian countries highlight the impact of cultural and ethnic factors, and variations in diagnostic criteria, cut-off values and assessment methods contribute to the observed heterogeneity in reported rates. This review outlines diverse diagnostic criteria and several measurement techniques supporting decision making in clinical practice. Moreover, it facilitates the selection of appropriate tools to assess sarcopenia, emphasizing its multifactorial nature. Various scientific groups, including the European Working Group of Sarcopenia in Older People (EWGSOP), the International Working Group on Sarcopenia (IWGS), the Asian Working Group on Sarcopenia (AWGS), the American Foundation for the National Institutes of Health (FNIH) and the Sarcopenia Definition and Outcomes Consortium (SDOC), have published consensus papers outlining diverse definitions of sarcopenia. The choice of diagnostic criteria should be aligned with the specific objectives of the study or clinical practice, considering the characteristics of the study population and available resources.