Impedance Analysis Research Articles

The Influence of Body Fat Percentage on Body Type Cognitive Bias Among Young Chinese Hospital Staff Members: A Cross-Sectional Study

Aims/Background This study expanded the existing literature on obesity and distortion of body image by examining subjective and objective body type among young medical workers, specifically investigating whether fat percentage independently influences body type cognitive bias. Methods We recruited 264 participants (41.29% male, mean age 26.2 ± 3.1 years, mean body mass index (BMI) 21.7 ± 3.1 kg/m2) at a comprehensive hospital in central China. The questionnaire responses of the enrolled participants concerning basic information and body type self-assessment were extracted. Their weights and body compositions were evaluated by the bioelectrical impedance analysis technique (BIA). Objective indicators included measured weight, BMI, fat percentage, waist circumference (WC) and waist-to-hip ratio (WHR). Results Based on this sample, the prevalence rate of body type cognitive bias was 28.79%. For women, the univariate regression analysis showed that fat percentage was significantly correlated with body type cognitive bias (odds ratio [OR] 1.107, 95% confidence interval [CI] 1.033–1.185, p = 0.004). BMI (OR 1.303, 95% CI 1.098–1.546, p = 0.002) and WC (OR 1.109, 95% CI 1.043–1.180, p = 0.001) might also be positively associated with body type cognitive bias. After adjusting for age, BMI, WHR, and job position, the risk of body type cognitive bias decreased with fat percentage up to the first inflection point (26.8%) (OR 0.78, 95% CI 0.62–0.98, p = 0.036), and then it increased up to the second inflection point (33.0%). When fat percentage exceeded 33.0%, the relationship lost statistical significance. No significant relationships were found for men. Conclusion Fat percentage is an independent, nonlinear factor influencing women's body type cognitive bias. Gender and fat percentage should be considered when establishing weight management intervention strategies to prevent obesity from becoming a public health problem.

Functional effect of adiponectin and body composition assessment in lung cancer subjects after video-assisted thoracoscopic surgery (VATS) lobectomy.

Lung cancer is a pathology with an important incidence. It is a multifactorial disease characterized by epigenetic and nutritional factors. Indeed, there is a strong association between adipose tissue and the pulmonary system, and low-grade inflammation of obese and/or overweight subjects have a pivotal role in lung cancer establishment. In this study, we analyzed body composition through bioelectrical impedance analysis (BIA) and biochemical parameters such as glycemic and lipidic profile, inflammation profile and adiponectin serum levels in 30 patients (19 male; 11 women) undergoing video-assisted thoracoscopic surgery (VATS) lobectomy for lung cancer from September 2021 to May 2022 at the Thoracic Unit of Luigi Vanvitelli University of Naples. A control group were also recruited (15 male; 15 female) consisting of age and sex matched volunteered subjects at the Thoracic Unit of Luigi Vanvitelli University of Naples. The control group and lung cancer patients were monitored for anthropometric and biochemical parameters before VATS lobectomy. Furthermore, the lung cancer patients were also monitored after 6 months of surgery. Body composition is modified after surgery and also albumin and C-reactive protein (CRP) serum levels. In the overweight patients in our study, adiponectin levels were found to be reduced compared with the control group and increased in the same patients after VATS lobectomy. Tumor removal as well as weight loss could affect adiponectin levels, and thus also a reduction in inflammation. In addition, weight loss could also be due to a psychological condition given by the intervention and not to malnutrition related to therapy.

Physical activity and cardiometabolic risk factors in sprint and jump-trained masters athletes, young athletes and non-physically active men

Abstract Objectives Assessing physical activity and cardiometabolic risk in masters athletes as an example of very high physical activity at old age. Methods Forty-three men were studied in full factorial design, either as sprint or jump-trained masters athletes (MA, n=10, age 60–75 years), as young sprint or jump-trained athletes (YA, n=10, age 20–35 years), older control participants (OC, n=11, age 60–75 years) or as young control participants (AC, n=12, age 20–35 years). We performed bio-electrical impedance analysis and assessed serum markers of lipids and glucose metabolism and C-reactive protein, structured training hours, and habitual activity via mobile actimetry. Results Body fat was greater in OC than in MA (23.9 [SD 4.2] % vs. 14.0 [SD 5.7] %, p<0.001), and also greater than in YA and YC (both p<0.001). Weekly training hours were comparable between MA and YA (7.9 [SD3.3] hours vs. 11.1 [SD 4.8] hours, p=0.69). Habitual walking distance was greater in MA than in OC (7,387 [SD 4,923] m/day vs. 4,110 [SD 1,772] m/day, p=0.039), and so was habitual running distance (667 [SD690] m/day vs. 132 [427] m/day, p<0.001). HOMA-index was greater in OC than in MA (2.07 [SD 1.39] vs. 0.80 [SD 0.41], p=0.0039), and so was C-reactive protein (1.35 [SD 1.74] mg/l vs. 0.58 [SD 0.27] mg/ml, p=0.018), whereas serum lipids showed only moderate or no effect (all p between 0.036 and 0.07). Conclusions Improved body composition and physical activity levels in MA are associated with lower cardiometabolic risk, which seems more pronounced for insulin sensitivity and inflammaging than for lipid metabolism.

Evaluating the Clinical Applicability of Multifrequency Bioelectrical Impedance Analysis for Nutritional Status Prediction in Hospitalized Persons With Severe Motor and Intellectual Disabilities.

Persons with severe motor and intellectual disabilities (SMID) have difficulty using general nutritional assessments in the elderly and other populations because of their physical characteristics. The purpose of this study was to investigate the clinical utility of body composition, which has been suggested to be related to biochemical tests in persons with SMID. We calculated cutoff values of body composition predicting malnutrition and compared the usage of peripheral parenteral nutrition for the two groups divided by each body composition cutoff value. We also compared body composition at the baseline between nonsurvivors and survivors. Only group comparisons based on skeletal muscle ratio and extracellular water to total body water (ECW/TBW) cutoffs showed significant differences in the usage of peripheral parenteral nutrition. Nonsurvivors had significantly higher ECW/TBW than survivors at the baseline. In persons with SMID, skeletal muscle ratio and ECW/TBW measured using multifrequency bioelectrical impedance were associated with biochemical indices and ill health. Furthermore, ECW/TBW was also associated with mortality, suggesting that ECW/TBW is a significant measure for nutritional assessment in clinical practice.

Probing structural, surface morphological, optical, low temperature magnetic studies and electrochemical studies on gadolinium tellurite (GdTeO3)

Abstract Gadolinium tellurite (GdTeO3) has been synthesized by hydrothermal process. It displays both tiny nanorods and spherical particles embedded in a structure resembling flakes. Using a particle size analyzer, the size of the particle is found to be 142.5 nm. GdTeO3 has a cubic structure. Urbach energy is 0.4566 eV, energy gap is 5.797 eV, and refractive index is 1.890. The sample is suitable as UV filter and an effective applicant of optoelectronics. The bands observed in UV spectrum are assigned with the transitions between energy levels of Gd and attributed to different surface defects. The bands seen in the spectrum are linked to Gd’s energy level transitions and have various surface imperfections. The sample contained tellurite in an oxide matrix containing gadolinium. Magnetic analysis indicates that GdTeO3 may be undergoing a phase transition and may contain a small impurity. At 300 K, the M−H curve demonstrates paramagnetic and weak ferromagnetic characteristics with aligned cooperative Gadolinium spins. Pseudocapacitive behavior is shown by the cyclic voltammogram and Cp analysis. The sample exhibits 0.90 V potential window. It has been observed that specific capacitance is 139.34 Fg−1 from cyclic voltammogram and 112.93 Fg−1 from Cp analysis. Analysis of impedance reveals a pseudo-capacitive character.

Preparation for Powerlifting Competition: A Case Study

This study assessed a male competitive powerlifter over a 6-month period that encompassed his pre-contest preparation and post-contest recovery. We conducted the following monthly assessments: multi-frequency bioelectrical impedance analysis (MF-BIA), B-mode ultrasound evaluation of muscle thickness (MT), body circumferences, handgrip strength, vertical jump height, isometric lower body strength, and questionnaires for perceived mood and sleep. The athlete undertook a 3-month pre-contest preparatory period that included an extreme energy-restricted diet intended to sufficiently reduce body mass. This period also included an 8-week pre-contest training regimen with a 10-day taper intended to promote peak strength increases in the target lifts for competition. During the pre-competition period, the athlete experienced rapid and substantial losses of body mass (10.3%), body fat (6.5%) and lean mass (3.3%), the majority of which was regained in the 2-month post-competition recovery phase. The athlete's isometric knee extension strength rose sharply during the initial month of the pre-competition phase (336.4 Nm), followed by consistent declines (299 to 262.2 to 283 Nm) over the next 3 months, eventually returning close to baseline values 2 months post- competition Jump height remained steady in the 3 months in the pre-contest phase but increased (+1.4 cm) in the 2 months post-competition while handgrip strength increased during the months preceding the competition (47.5 kg to 49 kg) but decreased to 42.3 cm post-competition. Overall, the athlete did not seem to have any marked sleep disturbances. The most notable changes in mood parameters were increased tension, anger, and depression immediately preceding the competition.

Influence of sarcopenia as determined by bioelectrical impedance analysis in acute pancreatitis.

Sarcopenia can be defined as the loss of muscle mass and strength. It is a poor prognostic factor for many diseases. Our study aims to assess the prevalence of sarcopenia in patients with acute pancreatitis using bioelectrical impedance analysis (BIA) and hand dynamometry while also investigating its impact on acute pancreatitis. Sixty patients admitted with a diagnosis of acute pancreatitis were included in this prospective study. Following their admissions, prognostic markers were calculated, muscle strengths were measured using a hand dynamometer, and body compositions were determined using a BIA device. Accordingly, acute pancreatitis patients were divided into 2 groups: sarcopenic and nonsarcopenic. The demographic characteristics, anthropometric measurements, Ranson score, Glasgow-Imrie score, Balthazar score, APACHE-II score, disease severity according to the Atlanta classification, length of hospital stay, and laboratory findings of the 2 groups were compared. Sarcopenia was identified in 11 cases among those with acute pancreatitis included in the study. In the sarcopenic group, the mean age, Glasgow-Imrie score and number of cases with severe acute pancreatitis according to the Atlanta classification were significantly higher; body mass index, upper arm circumference, skeletal muscle mass index, and grip strength were significantly lower (P < .05). This study is the first to evaluate sarcopenia in acute pancreatitis cases using BIA and hand dynamometry. Sarcopenia may play a significant role in predicting the prognosis of acute pancreatitis.

Frequency-dependent equivalent impedance analysis for optimizing vehicle inertial suspensions

Frequency-dependent equivalent impedance analysis for optimizing vehicle inertial suspensions

Toward Efficient Hydrogen Generation Using Nickel-Molybdenum Catalyst and Its Environmental Sustainability.

In this study, a catalyst with Ni-Mo combination was synthesized using the electric heating/reductive tempering method. Nickel (II) nitrate hexahydrate and ammonium molybdate were combined in a ratio of 1.1 in this approach. The mixture was milled into a fine powder. It was heated to 950°C to 1000°C in a seething hood. The disappearance of green shading and emission of brownish-yellow fumes indicated that the reaction was completed. XRD has been used to determine the crystallinity of the combined Ni-Mo amalgam, SEM was used to investigate the surface morphology of the orchestrated Ni-Mo compound, and inductively coupled plasma examinations were carried out to evaluate elemental percentage (%) of the integrated sample of Ni-Mo combination. In addition, an electrical impedance analysis of as-synthesized Ni-Mo alloy was conducted to estimate hydrogen production in an electrochemical reaction. The electrical impedance results indicate that the synthesized Ni-Mo catalyst exhibited an efficient charge-transfer kinetics with a low charge-transfer resistance (5.35 Ω). The onset potential value achieved was 18 mV with overpotential of -100 mV in IM KOH, possessing a turnover frequency of 0.91H2 s-1. These findings underscore Ni-Mo catalyst as a promising catalyst for hydrogen generation studies. The results of this study are anticipated to be of potential significant importance in providing a cost-effective approach towards the synthesis of Ni-bimetallic catalyst, which in the future can serve as a promising candidate for applications involving sustainable hydrogen generation. Additionally, the proposed method's study of its greenness using the Analytical Greenness Calculator (AGREE) can help advance the usage of renewable and environmentally friendly energy sources.

Nutritional Gender-Specific Differences in Head and Neck Cancer Patients Treated with (Chemo)Radiotherapy: Results from a Prospective Trial.

Background/Objectives: This analysis aims to evaluate gender-specific differences in nutritional status, body weight changes, and their impact on overall survival (OS) in head and neck cancer (HNC) patients undergoing (chemo)radiotherapy (CRT). Methods: Between 2018 and 2020, 61 HNC (17 female and 44 male) patients were prospectively recruited to receive curative (chemo)radiotherapy. Nutritional assessments included dietary questionnaire screenings and records, anthropometric methods (body mass index, BMI, body composition via bioelectrical impedance analysis (BIA)), and the determination of biomarkers like albumin and CRP. Assessments were conducted before, during, and after (chemo)radiotherapy. Results: Gender differences were observed at baseline in Karnofsky performance status (p = 0.01), daily calorie intake (p = 0.04), phase angle (PA) (p = 0.003), and fat-free mass index (FFMI) (p < 0.001). During CRT, males showed a larger increase in calorie deficit (p < 0.001) and greater reductions in BMI, FFMI, and PA compared to females. Malnutrition risk (MUST score) increased significantly in males (p = 0.008) but not in females. Albumin and total protein declined in both genders, with a more pronounced drop in albumin for females. Survival analysis revealed that, for males, several factors, including baseline calorie deficit, BMI, PA, and FFMI, were linked to survival. For females, only albumin at therapy end was significantly associated with survival (p < 0.001). In multivariable analysis, baseline PA remained a significant predictor of survival for males (p = 0.026). Conclusions: Our findings suggest distinct gender differences in the nutritional and biochemical responses of HNC patients undergoing CRT, indicating the importance of tailored, gender-specific nutritional support during treatment.

The role of body composition in neurological and hematologic toxicity in a retrospective analysis of 120 breast cancer patients undergoing neoadjuvant chemotherapy: the COMBOTOX study.

Neoadjuvant chemotherapy (NAC) has a well-established role in locally advanced or chemoresponsive breast cancers (BC). Chemotherapic regimens are effective when patients receive the optimal doses. Toxicities are common in overweight/obese patients but may occur also in normal weight counterparts. This leads to delays, reductions, or discontinuation of treatment, with impact on outcomes. Current dosing is based on body weight and predicted Body Surface Area (BSA). These parameters do not take into consideration the individual variations of fat mass (FM) and fat-free mass (FFM) that affect pharmacokinetics. Assessment of body composition (BoCo), rather than Body Mass Index (BMI), could help to better plan chemotherapy and reduce drug-related toxicities. Our aim was to analyze the correlations between body weight, anthropometric measures, BoCO, and toxicities related to NAC in non-metastatic BC patients. This is a retrospective observational cohort study that includes 120 consecutive BC patients undergoing NAC, enrolled between May 2018 and December 2020. All patients received an evaluation of anthropometric parameters (height, weight, waist and hip circumference, BMI) and an assessment of BoCo using Segmental Multi-Frequency-Bioelectrical Impedance Analysis. A logistic regression models confirmed that a higher FM was associated with a higher rate of neurological and hematologic toxicities in protocols containing Platinum. Moreover, patients with a low FFM% have a higher risk for hematologic toxicity in protocols containing Platinum. A routine assessment of BoCo, in addition to evaluation of anthropometric measures and BMI, could allow to personalize chemotherapy doses, in order to reduce chemotherapy-related toxicities.

Relationship between characteristics of segmental phase angles and walking ability in patients with hemiplegia after stroke and traumatic brain injury in a convalescent rehabilitation ward.

This study determined the characteristics of the phase angles (PhAs) of the trunk, affected limb, and unaffected limb at admission and their relationship with walking ability at discharge in patients with stroke and traumatic brain injury in a convalescent rehabilitation ward. Stroke and traumatic brain injury survivors with hemiplegia admitted to a convalescent rehabilitation ward were divided into independent- and dependent-walking groups. The trunk, affected limb, and unaffected limb PhAs were evaluated using bioelectrical impedance analysis and compared between the independent- and dependent-walking groups. Friedman's test was performed to analyze differences in the trunk, affected limb, and unaffected limb PhAs within each group. Multiple regression was performed to examine the association between walking ability and segmental PhAs. We enrolled 47 patients (independent-walking group: n = 12; dependent-walking group: n = 35). The dependent-walking group had a significantly lower trunk, affected limb, and unaffected limb PhAs. The segmental PhA was higher in the trunk than in the affected and unaffected limbs in the independent-walking group and lower in the affected limb than in the trunk and unaffected limb in the dependent-walking group. Only the trunk PhA at admission was significantly associated with walking ability at discharge (β = 0.367; P = 0.002). The trunk PhA at admission may be related to walking ability at discharge in patients undergoing stroke and traumatic brain injury rehabilitation.

Hall effect thruster impedance characterization in ground-based vacuum test facilities

Hall effect thrusters (HETs) are typically regarded as DC electric propulsion devices as they are operated with isolated DC power supplies. However, it is well known that the HET’s discharge current possesses oscillations of varying magnitudes and frequencies and is thus a function of time with AC characteristics. The observed oscillations are caused by plasma processes associated with ion, electron, and neutral particle dynamics that occur inside the HET’s discharge channel and in the plume as the HET electrically interacts with its local operating environment. The extent to which plasma oscillations impact HET discharge dynamics is difficult to quantify due to the complexity of analyzing AC signals, given that the HET is a nonlinear, time-variant electrical load. In this work, we overcome the challenge of nonlinearity and time-variance of HETs by conducting a small-signal impedance analysis to characterize the effective resistance and reactance of the HET discharge with a novel and versatile impedance measurement diagnostic. The impedance magnitude and phase of a 7-kW class HET were measured from 100 Hz to 300 kHz with an excitation signal of ± 2 Vpk for two discharge operating conditions on krypton: 4.5 kW, 15 A and 6 kW, 20 A. The results were used to quantify resistive, capacitive, and inducive characteristics present within the HET discharge signature. For the 4.5 kW, 15 A thruster operating condition, the breathing mode capacitance was estimated to be 12.6 µF with an inductance of 15.3 µH. Furthermore, the impedance characteristics of the breathing mode are within ± 2.4 kHz of the power spectral density plots independently generated by time-resolved oscilloscope traces indicating good agreement in the frequency domain. Thus, the impedance measurement tool is a new diagnostic for characterizing the impedance and associated AC characteristics of HETs.

Diagnostic accuracy of isometric knee extension strength as a sarcopenia criteria in older women

BackgroundMuscle strength is one of the most reliable measures used for the identification of sarcopenia. The European Working Group on Sarcopenia in Older People update (EWGSOP2) proposed the use of grip strength and chair stand tests, while clarifying that isometric torque methods can be used when performing the grip strength test is impossible. This study aims to evaluate the diagnostic accuracy of isometric knee extension strength in screening for sarcopenia.MethodsThis cross-sectional study included community-dwelling women aged 70 years and over. IKE and sarcopenia criteria (EWGSOP2) were assessed. Skeletal muscle mass was assessed by bioelectrical impedance analysis; muscle mass strength by handgrip; and physical performance by the 5 times sit-to-stand test, the Short Physical Performance Battery, and gait speed. The diagnostic accuracy for each sarcopenia criterion was calculated using sensitivity, specificity, positive and negative predictive value, and the area under the curve (AUC). Cutoff points for sarcopenia from IKE were defined with the ROC curve.ResultsThe sample comprised 94 women with a mean age of 75.9 years (standard deviation 5.6, range 70–92), of whom 25.5% (n = 24) met criteria for sarcopenia—mainly severe sarcopenia (73.8%, n = 17). Correlations were observed between IKE and each individually analyzed sarcopenia criterion except skeletal muscle mass, with AUC values exceeding 0.70 in all cases. The IKE cutoff showing the highest accuracy for the diagnosis of sarcopenia was 12.5 kg or less (AUC 0.76, 95% confidence interval [CI] 0.64–0.88; sensitivity: 65.2%, 95% CI 45.7–84.7; specificity 77.4%, 95% CI 60.3–94.5; positive predictive value 62.5%, 95 CI% 42.7–82.3; negative predictive value 88.8%, 95% CI 75.9–100).ConclusionsIKE could be a suitable tool for measuring muscular strength in sarcopenia when other strength parameters cannot be assessed or in people with walking difficulties.

Synthesis and functional properties of reduced graphene oxide/bismuth-doped gadolinium ferrite composites

An upsurge in water pollution with developing age leads scientists to exploit new materials and technologies for water purification. Herein, we used a co-precipitation approach to prepare rGO/BixGd1-xFeO3 composites to tackle waste organic dyes in fresh water reservoirs. Bismuth at different concentrations is used to tailor the functionality of gadolinium ferrites deposited on reduced graphene oxide. X-ray diffraction pattern describes the unit cell structure of the composite to be distorted orthorhombic with crystallite sizes in the range of 20-15 nm which are confirmed by scanning electron microscopy. Band gaps are calculated by Tauc plots and are in the range 2.62-2.38 eV and 0.9945-0.2873 eV for direct and indirect calculations making these composites suitable photocatalysts. Textural analysis of the samples is carried by Brunauer-Emmett-Teller surface measurements and the surface area is found to be in the range 62.1 to 29.9 m2g−1. Dielectric studies prove that rGO/Bi0.05Gd0.95FeO3, with the highest dielectric constant and capacitance, is better semiconductor among all six synthesized composites. This result is further supported by impedance analysis. In the presence of ultraviolet-visible light, rGO/Bi0.05Gd0.95FeO3 shows 97.2% degradation of methylene blue dye, a common industrial pollutant, with rate constant 0.006 min−1 while rGO/GdFeO3 only degraded 72.6% of MB. The enhanced photocatalytic ability of rGO/Bi0.05Gd0.95FeO3 is evident through low band gap, small crystallite size, less electron-hole recombination in photoluminescence, large surface area and linear I-V response.

A comparative analysis of constant impedance and constant power loads in a distribution network

A comparative analysis of constant impedance and constant power loads in a distribution network

Exploring the structural, optical, impedance and ferroelectric analysis of Ba0.97Ca0.03Nb0.08Zr0.45Ti0.45O3 ceramic prepared by the sol-gel combustion method

Exploring the structural, optical, impedance and ferroelectric analysis of Ba0.97Ca0.03Nb0.08Zr0.45Ti0.45O3 ceramic prepared by the sol-gel combustion method

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.

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. 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. 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. These findings suggest that using FFM derived from DXA or BIA results in similar RMR estimates in resistance-trained men.

Phase angle as a marker of muscle quality: A systematic review and meta-analysis

Background & aimsPhase angle (PhA) is a biomarker derived from raw bioelectrical impedance analysis (BIA) values: resistance (R) and reactance (Xc). PhA reflects cellular membrane integrity and, as a result, has been considered a marker of fluid distribution, making it a potential prognostic indicator. A growing body of research demonstrates independent associations between PhA and muscle strength, mass, and composition. In this context, PhA has the extra potential to serve as a marker of muscle quality. However, the evidence supporting its use for this purpose is not well established. This study aimed to investigate the relationship between PhA and markers of muscle quality. MethodsThis systematic review and meta-analysis (Internal Prospective Register of Systematic Reviews – PROSPERO on a registration code: CRD42024507853) focused on observational studies assessing the relationship between PhA and markers of both concepts of muscle quality: the muscle quality index (MQI: strength by a unit of mass) and the muscle composition (i.e., skeletal muscle radiodensity [SMD], muscle echogenicity, muscle fat fraction, inter- and intramuscular adiposity). Risk of bias was assessed using the Newcastle-Ottawa Scale (NOS) and Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2), while the certainty of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Meta-analyses with a random-effects model were conducted. ResultsSeventeen studies were included in this systematic review, encompassing 2,710 participants. Meta-analyses demonstrated that PhA had a moderate positive correlation coefficient with SMD (4 studies, 924 participants; r = 0.54, 95% confidence interval (CI) 0.38 to 0.69, heterogeneity (I2) = 92%) and good accuracy (85%) for classifying low SMD (2 studies, 390 participants; Area Under the Curve – AUC pooled 0.85, 95% CI 0.78 to 0.92, I2 = 0%). PhA was inversely-moderately correlated with muscle echogenicity (8 studies, 1,401 participants; r = - 0.42, 95% CI - 0.57 to - 0.24, I2 = 82%) and positively-weakly correlated with MQI (2 studies, 191 participants; r = 0.36, 95% CI 0.21 to 0.49, I2 = 17%). All studies had a higher risk of bias. The certainty of evidence ranged from low to very low. ConclusionDespite technical challenges, this study demonstrates the potential of PhA as a surrogate marker for muscle quality, particularly expressing muscle composition (SMD). Future studies should utilize BIA with standardized protocols to potentially establish specific cutoff values for PhA, thereby enhancing its diagnostic accuracy and clinical applicability. These studies could additionally explore the mechanisms underlying the associations between PhA and muscle quality aspects. In cases where technical factors are not easily controlled, the use of standardized PhA (SPhA), which converts PhA into Z-scores, could be beneficial. Although this warrants investigation, this approach (SPhA) has the potential to account for variables such as age, sex, device differences, and health status.

Relationship of visceral adiposity index (VAI) and visceral body fat among metabolically obese normal weight individuals from Pakistan

BackgroundAn increasing number of people throughout the world are suffering with visceral obesity. Accumulation of visceral fat is a pathogenic manifestation of global fat dysfunction, that leads to inflammation, atherosclerosis, abnormal lipid levels, and high blood pressure. MethodsThis association study was conducted at Department of Medicine, Mayo Hospital Lahore, Pakistan. 30 participants who meet the selection criteria were recruited after taking written consent. Then patients were evaluated for their height, weight and waist circumference body mass index. Visceral fat was calculated by using machine for bio-impendence analysis. Visceral adiposity index was calculated. 5cc venous blood sample was’ collected under aseptic measures and all samples were sent to the hospital’s laboratory for assessment of lipid profile and blood sugar levels. ResultsWe have studied 30 patients (43.8% female and 56.3% male), mean age of study population calculated was 40.6 ±11.80 years. The mean Visceral Body Fat was found to be 13.53 ± 1.41, High-Density Lipoprotein cholesterol mean calculated was 36.91 ± 9.18 mg/dL, and mean Visceral Adiposity Index calculated was 16.75 ± 7.55. Pearson Correlation was used, to find correlation between Visceral Adiposity Index and Visceral Body fat. The value turned out to be .899** shows positive correlation, p- value was 0. 001 significant. ConclusionIn this study we found positive correlation of visceral adiposity index and visceral body fat by use of Bio impedance analysis machine among metabolically obese normal weight individuals. Visceral adiposity index requires many blood tests while Bio impedance analysis machine can be used in simple outdoor settings hence, we can isolate high risk patient in outdoor settings without any invasive procedures or laboratory investigations.