title: Association between cardiac autonomic function, oxidative stress and inflammatory response in impaired fasting glucose subjects: cross-sectional study.
abstract: BACKGROUND
  The worldwide burden of diabetes in 2030 is projected around 552 million. Diabetes leads to higher risk for cardiovascular diseases (CVD). Altered cardiac autonomic function (CAF) measured by heart rate variability (HRV) is observed in early stages of diabetes but the relationship between impaired fasting glucose (IFG) and HRV is still debatable. The aim of the study was to evaluate the association between CAF, oxidative stress, insulin resistance (IR), and inflammatory response in IFG subjects.
  
  
  METHODS
  Cross-sectional blinded study. Volunteers recruited from health awareness camps underwent CAF and biochemical tests. Based on fasting plasma glucose (FPG) participants (n = 123) were divided into two groups, normal fasting glucose (n = 76) and IFG (n = 47). The comparison of parameters between the groups was carried out using student t test and Mann-Whitney U test for parametric and non-parametric data respectively. The correlation between the parameters was analyzed by Spearman's rank correlation using SPSS 13.0.
  
  
  RESULTS
  The resting cardiovagal modulation parameters, heart rate response to forced timed breathing, and orthostatic stress were reduced in IFG subjects. Fasting plasma lipid profile, coronary atherogenic lipid risk factors, IR, thiobarbituric acid reactive substance (TBARS), high sensitive C-reactive protein, and tumor necrosis factor alpha were increased and total antioxidant capacity (TAC) was decreased significantly in IFG group but no significant alteration was observed in high-density lipoprotein (HDL-c). Cardiovagal modulation parameters were negatively correlated with triglycerides, FPG, insulin, IR, TBARS, and inflammatory markers and positively with TAC.
  
  
  CONCLUSIONS
  There is a continuous interplay between the altered CAF, hyperinsulinemia, IR, oxidative stress parameters, inflammatory response, and IFG in which one factor perpetuates another leading to the progression of disease.
authors.affiliation: Department of Physiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, India.
authors.forename: Ramkumar
authors.initials: R
authors.lastname: Thiyagarajan
authors.forename: Senthil Kumar
authors.initials: SK
authors.lastname: Subramanian
authors.forename: Nishanth
authors.initials: N
authors.lastname: Sampath
authors.lastname: Madanmohan Trakroo
authors.forename: Pravati
authors.initials: P
authors.lastname: Pal
authors.forename: Zachariah
authors.initials: Z
authors.lastname: Bobby
authors.forename: Sankar
authors.initials: S
authors.lastname: Paneerselvam
authors.forename: Ashok Kumar
authors.initials: AK
authors.lastname: Das
mesh_terms: D000328:Adult; D001341:Autonomic Nervous System; D001786:Blood Glucose; D001794:Blood Pressure; D002097:C-Reactive Protein / Q000378:metabolism; D003430:Cross-Sectional Studies; D005260:Female; D006339:Heart Rate; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood*; D007333:Insulin Resistance; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D011236:Prediabetic State / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D012307:Risk Factors; D018709:Statistics, Nonparametric; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D014636:Valsalva Maneuver
chemical_list: D001786:Blood Glucose; D018836:Inflammation Mediators; D008055:Lipids; D017392:Thiobarbituric Acid Reactive Substances; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein