ABSTRACT
Visceral fat is a predictor of obesity, metabolic syndrome and type II diabetes. The presently available technique, Computed tomography (CT) causes radiation exposure and is expensive. Abdominal obesity is a well established risk factor for obesity. There tends to be a risk of development of type 2 diabetes in obese individuals with abdominal obesity and insulin resistance. Abdominal obesity includes both subcutaneous and intra abdominal (visceral) adipose tissue and is associated with an increased risk of coronary heart disease (CHD) morbidity. A positive correlation between visceral fat, insulin levels and homeostasis model assessment insulin resistance index (HOMA-IR) in both genders was verified (r = 0.522 in boys and r = 0.309 in girls). The study aims at developing a bioelectrical impedance based system for visceral fat area. The visceral fat area of 126 subjects (age: 38 ± 9 years) was first measured using the commercial instrument InBody 720 (Biospace, Korea) and then using the body composition analyzer (BCA) Bhabha Atomic Research Centre (BARC, Mumbai). Tetrapolar bioelectric impedance analysis (BIA) using two frequencies (50 KHz and 6.25 KHz) was used to develop the regression equation as follows: VFA = [-142 + 187* whr + 1.94* weight (Kg) + 0.135* Zbody 50 (μ) + 1.027* age (years) -0.97* height (cm) + 7.2* sex -1.40* Zbody 50/W (μ Kg-1)] cm2; Sex = 0 for women and 1 for men (with R-sq adj = 96.87 and S = 5.37). The equation thus developed using BCA (BARC, Mumbai), validated with 60 subjects shows that there exists a high degree of correlation (R-sq adj = 96.87) between the two techniques.
ABSTRACT
Based on the past observation of recording abnormal impedance cardiogram (ICG) in 13% normal subjects and subsequent detection of coronary artery disease (CAD) in majority of these cases, led the authors to record peripheral impedance plethysmograms (IPG) in control subjects and patients using impedance cardiovasograph, developed by electronics division, Bhabha Atomic Research Centre (BARC). Analysis of peripheral plethysmograms, thus recorded, has shown 8 dominant morphological patterns of the peripheral pulses depending upon their status of health. In cognizance of these observations, different methods of pattern analysis were used for pattern identification. Fourier Transform based method has been observed to yield higher diagnostic yield. Morphology index (MI) of the peripheral pulse derived from this method was observed to vary from 0.28 to 1, the former indicating the poorest and later the normal health. Among 100 subjects suffering from various disorders, 8 patients with coronary artery disease have recorded average index to be between 0.30 and 0.45.