title: Anthropometric Predictors of Bio-Impedance Analysis (BIA) Phase Angle in Healthy Adults.
abstract: BACKGROUND
  Phase Angle (PhA) is a ratio of whole body reactance and resistance obtained from Bioelectrical Impedance Analysis (BIA). It indicates cellular health and integrity and is considered as prognostic tool in medical disorders. In spite of prognostic potentials of PhA, it has limited usefulness in clinical practice and in population studies because of non-availability of normal population reference limits for comparison. Moreover, it is influenced by various factors like age, sex, race and body composition (i.e. body fat, muscle mass, visceral fat, body cell mass, total body water, etc).
  
  
  OBJECTIVE
  The aim of this study was to evaluate predictors of phase angle which will be useful in formulation of reference values for Indian population.
  
  
  METHODS
  BIA was performed by Tanita Body Composition Analyser on healthy adults aged 17-24 years. The inbuilt software measured the phase angle by the formula: Phase angle (PhA) = Reactance (xc)/Resistance (R)* (180/π). Phase angle values were compared across categories of age, sex, weight, height, Body Mass Index (BMI), total fat, visceral fat and muscle mass.
  
  
  RESULTS
  Mean value of phase angle was found to be 5.65. Phase angle was significantly (p< 0.001) higher in male than in female. Phase angle was significantly predicted from height (p< 0.001), weight (p< 0.002), muscle mass (p< 0.002) and visceral fat (p< 0.02) in multiple regression models.
  
  
  CONCLUSIONS
  Phase angle differs across anthropometric and body composition categories. Thus height, weight and muscle mass should also be taken into consideration while deriving population specific reference limits of phase angle.
authors: Professor, Department of Physiology, Sri Aurobindo Medical College and Post Graduate Institute , Indore, Madhya Pradesh, India .
authors: Nazeem Ishrat
authors: NI
authors: Siddiqui
authors: Associate Professor, Department of Pharmacology, CIMS Bilaspur, Chhattisgarh, India .
authors: Sarfaraz Alam
authors: SA
authors: Khan
authors: Assistant Professor, Department of Biotechnology, SSMV , Bhilai, Chhattisgarh, India .
authors: Mohammad
authors: M
authors: Shoeb
authors: Director Professor, Department of Physiology and Director Medical Education, Sri Aurobindo Medical College and Post Graduate Institute , Indore, Madhya Pradesh, India .
authors: Sukhwant
authors: S
authors: Bose
keywords: Anthropometric predictors; Bio-Impedance Analysis; Body composition analysis; Phase angle; Reactance and resistance