Methodology for integrated analysis of vector- and spectroscopic bioimpedance methods

Abstract

Electrical bioimpedance is based on the opposition exerted by body tissues to the passage of an electrical current. This characteristic allows the assessment of the individual's body composition, nutritional status, and hydration status. Electrical bioimpedance can be used to estimate body composition, health-related markers, general health status, diagnosis and prognostic of diseases, evaluation of treatment progress, and others. The aim of this study is to propose a methodology that allows us to integrate two methods of electrical bioimpedance analysis: bioelectrical impedance vector analysis, and bioelectrical impedance spectroscopy to evaluate the health of individuals. For methodology validation a retrospective clinical investigation was carried out where the data of healthy individuals and cancer patients included in the Database of the characterization of bioelectrical parameters by electrical Bioimpedance methods were analyzed. The values of electrical resistance and electrical reactance are higher in cancer patients compared to healthy individuals. However, the phase angle is lower in these patients. In the advanced stages of the disease, patients are located outside the tolerance ellipses. All these results are obtained at the characteristic frequency. The integration of bioelectrical impedance vector analysis, and bioelectrical impedance spectroscopy can be a sensitive complementary tool, capable of establishing differences between healthy individuals and cancer patients. Enrichment could be achieved by including the analysis of different physiological parameters through estimation equations validated by BIS parameters.

Keywords: Bioimpedance; body composition; tolerance ellipses.

Fig. 1:

Ellipses of tolerances of a healthy population at the characteristic frequency. A) female individuals (n = 24): (Δ) patients with cancer located in the fourth quadrant (Q IV); (■) average Cole's arc of the group of patients belonging to the fourth quadrant with a maximum value within the 75% ellipse (located Q IV-2); (○) Average reference Cole's arc of a healthy female population belonging to the fourth quadrant, whose maximum value is located within the 50% ellipse (Q IV-1). B) Male individuals (n = 18): (▲) patients with cancer located in the fourth quadrant (Q IV); (○) average Cole's arc of the patient group belonging to the fourth quadrant with a maximum value outside the 95% ellipse (Q IV-3); (Δ) Average reference Cole's arc of a healthy male population belonging to the fourth quadrant, whose maximum value is located within the 50% ellipse (Q IV-1).

Fig. 2:

Ellipses of tolerances of a healthy female population at the characteristic frequency; (Δ) reference Cole's arc of a healthy female population, belonging to the fourth quadrant with a maximum value located within the 50% ellipse (Q IV-1). Cole's arches in four female patients diagnosed with cancer, by anatomical pathology laboratory: (•) Cole's arc of a patient with cervical neoplasia (stage Ib), with a maximum value located in the fourth quadrant and within the 75% tolerance ellipse (Q IV-1); (○) Cole's arc of a patient with breast neoplasm (stage IIIb), with maximum value located in the fourth quadrant quadrant and within the 50% tolerance ellipse (Q IV-1); (▲) Cole's arc of a patient with cervical neoplasia (stage IIIb), with a maximum value located outside 95% tolerance ellipse (Q IV-3); (■) Cole's arc of a patient with endometrial cancer (stage IIb), with a maximum value located in the fourth quadrant and within the 95% tolerance ellipse (Q IV-2).

Fig. 3:

Ellipses of tolerances of a healthy male population at the characteristic frequency; (Δ) reference Cole's arc of a healthy male population, belonging to the fourth quadrant with a maximum value located within the 50% ellipse (Q IV-1). Cole's arcs in four male patients diagnosed with cancer, by anatomical pathology laboratory: (•) Cole's arc of a patient with lung cancer (stage Ib), located in the fourth quadrant and outside the 95% tolerance ellipse (Q IV-3); (▲) Cole's arc of a 58-year-old patient with lung cancer (stage IIIb) located in the fourth quadrant and within the 75% tolerance ellipse (Q IV-1) with a characteristic frequency of 30 kHz; (■) Cole's arc from a patient with melanoma of the skin (stage III) located in the fourth quadrant and outside the 95% tolerance ellipse (Q IV-3); (○) Cole's arch of a patient with colon carcinoma (stage IV) located in the fourth quadrant and outside the 95% tolerance ellipse (Q IV-3).