Design of an Automatic System for Bioelectrical Impedance Phase Angle Measurement Using an Analog Multiplier

Abstract Background Acne is a chronic, inflammatory and debilitating skin disorder. Dietary factors and nutritional status are among the exacerbating factors of acne. Phase angle (PhA), a direct measure of Bioelectrical Impedance Analysis (BIA), represents an indicator of the chronic inflammatory state. The Mediterranean diet (MD) is a healthy dietary pattern that can exert anti-inflammatory effects in several inflammatory diseases. We aimed to investigate the difference in PhA and adherence to the MD and their associations with the severity of acne in a sample of naïve treatment patients with acne compared to control group. Materials In this cross-sectional, case–control, observational study, we enrolled 51 patients with acne and 51 control individuals. Body composition was evaluated by a BIA phase-sensitive system (50 kHz BIA 101 RJL, Akern Bioresearch, Florence, Italy, Akern). For adherence to the MD, we have used the PREvención con DIeta MEDiterránea (PREDIMED) questionnaire. The clinical severity of acne was assessed by using the global acne grading system (GAGS), a quantitative scoring system to assess acne severity. Results Patients with acne had a worse body composition, in particular smaller PhA (p = 0.003), and a lower adherence to the MD (p < 0.001) than the control group, in spite of no differences in gender, age and BMI between the two groups. Stratifying patients with acne according to GAGS categories, both PhA (p = 0.006) and PREDIMED score (p = 0.007) decreased significantly in severe acne than mild/moderate acne. The GAGS score was negative correlations with PhA (r = − 0.478, p < 0.001) and PREDIMED score (r = − 0.504, p < 0.001). The results of the multivariate analysis showed PhA and PREDIMED score were the major determinants of GAGS score (p < 0.001). The receiver operator characteristic (ROC) analysis reporting a value of PhA of ≤ 6.1° and a PREDIMED score of ≤ 9 identified patients with acne with the highest clinical severity of the disease. Conclusions Novel correlations were reported between PhA and the degree of adherence to the MD with acne severity. Of interest, PhA and PREDIMED scores might represent possible markers of the severity of acne in a clinical setting. This study highlights how a cooperation between dermatologist and nutritionists might provide a combination key in the complex management of acne patients.

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Bioelectrical Impedance Phase Angle and Its Determinants in Patients with Classic Congenital Adrenal Hyperplasia

Journal of the American College of Nutrition ◽

10.1080/07315724.2021.1895902 ◽

2021 ◽

pp. 1-8

Author(s):

Núbia Maria de Oliveira ◽

Raquel David Langer ◽

Sofia Helena Valente de Lemos-Marini ◽

Gil Guerra-Júnior ◽

Ezequiel Moreira Gonçalves

Keyword(s):

Congenital Adrenal Hyperplasia ◽

Phase Angle ◽

Bioelectrical Impedance ◽

Adrenal Hyperplasia ◽

Classic Congenital Adrenal Hyperplasia

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8. A Pilot Study of the Phase Angle of Renal Transplant Patients Attending Tallaght University Hospital Using A Bioelectrical Impedance Machine

Journal of Renal Nutrition ◽

10.1053/j.jrn.2021.01.013 ◽

2021 ◽

Vol 31 (2) ◽

pp. 222

Keyword(s):

Pilot Study ◽

Renal Transplant ◽

Phase Angle ◽

Bioelectrical Impedance ◽

University Hospital ◽

Transplant Patients ◽

Renal Transplant Patients

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Bioelectrical impedance phase angle as a prognostic indicator of survival in head-and-neck cancer

Current Oncology ◽

10.3747/co.23.3181 ◽

2016 ◽

Vol 23 (5) ◽

pp. 481 ◽

Cited By ~ 14

Author(s):

M.S. Wladysiuk ◽

R. Mlak ◽

K. Morshed ◽

W. Surtel ◽

A. Brzozowska ◽

...

Keyword(s):

Overall Survival ◽

Head And Neck Cancer ◽

Head And Neck ◽

Phase Angle ◽

Neck Cancer ◽

Bioelectrical Impedance ◽

Impedance Analysis ◽

Neck Surgery ◽

Department Head ◽

Nutrition Status

Background Phase angle could be an alternative to subjective global assessment for the assessment of nutrition status in patients with head-and-neck cancer.Methods We prospectively evaluated a cohort of 75 stage iiib and iv head-and-neck patients treated at the Otolaryngology Department, Head and Neck Surgery, Medical University of Lublin, Poland. Bioelectrical impedance analysis was performed in all patients using an analyzer that operated at 50 kHz. The phase angle was calculated as reactance divided by resistance (Xc/R) and expressed in degrees. The Kaplan–Meier method was used to calculate survival.Results Median overall survival in the cohort was 32.0 months. At the time of analysis, 47 deaths had been recorded in the cohort (62.7%). The risk of shortened overall survival was significantly higher in patients whose phase angle was less than 4.733 degrees than in the remaining patients (19.6 months vs. 45 months, p = 0.0489; chi-square: 3.88; hazard ratio: 1.8856; 95% confidence interval: 1.0031 to 3.5446).Conclusions Phase angle might be prognostic of survival in patients with advanced head-and-neck cancer. Further investigation in a larger population is required to confirm our results.

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Anthropometric, body composition and behavioural predictors of bioelectrical impedance phase angle in Polish young adults – preliminary results

Annals of Agricultural and Environmental Medicine ◽

10.26444/aaem/118153 ◽

2020 ◽

Vol 27 (1) ◽

pp. 91-98 ◽

Cited By ~ 1

Author(s):

Michał Skrzypek ◽

Bogdan Szponar ◽

Bartłomiej Drop ◽

Lech Panasiuk ◽

Maria Malm

Keyword(s):

Young Adults ◽

Body Composition ◽

Phase Angle ◽

Bioelectrical Impedance ◽

Preliminary Results

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Multifrecuency bioimpedance phase angle as a tool to predict maturation failure of native fistulae for hemodialysis

Journal of Clinical Nephrology ◽

10.29328/journal.jcn.1001076 ◽

2021 ◽

Vol 5 (2) ◽

pp. 061-066

Author(s):

Daza Lopez José Lucas ◽

Galindo John F ◽

Villaquiran Mónica R ◽

Valenzuela Emilio D ◽

Cardenas Andres ◽

...

Keyword(s):

At Risk ◽

Arteriovenous Fistula ◽

Phase Angle ◽

Vascular Access ◽

Roc Curve ◽

Statistical Significance ◽

Bioelectrical Impedance ◽

Hydration Status ◽

P Value ◽

Patients At Risk

Background and objectives: An arteriovenous fistula is considered to be an ideal vascular access for patients receiving hemodialysis, its main limitation is its high failure rate to achieve maturation and long-term functionality loss. Multiple strategies have attempted to identify patients at risk. Bioelectrical impedance has shown to be a valuable resource in the determination of the hydration status, and the measurement of the phase angle through this method has demonstrated to be a good indicator of the nutritional state and its related as a general marker of survival. The objective of this study is to analyze the role of plasma albumin and phase angle measured through bioelectrical impedance as tools useful for predicting failure of arteriovenous fistulas. Materials and methods: prospective observational study, including 104 patients with chronic kidney disease receiving hemodialysis who underwent a native arteriovenous fistula during a period of 24 months. Analyzing its clinical characteristics, laboratory and phase angle through electrical bioimpedance, both univariate and multivariate analysis was performed both with logistic regression, furthermore calculation of coordinates and ROC curve to establish a better cut-off point. Results: of the variables that were analyzed only the phase angle measurement showed statistical significance OR 2.61 (1.6 – 4.4) p - value 0.001 for predicting arteriovenous fistula failure. In female patients with a phase angle value of 3.25 had a 90% sensibility and 53% specificity for male patients a value of 3.58 showed a sensibility of 84% and a specificity of 52% with ROC curve of 0.78. Conclusion: phase angle through bioimpedance is a useful parameter, helpful in predicting failure of native arteriovenous fistula, it is also an important tool for identifying patients at risk, in early stages prior to the construction of a vascular access.

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