title: Heart rate variability in middle-aged men with new-onset hypertension.
abstract: BACKGROUND
  It has been well established that hypertension is associated with autonomic dysregulation. Studies investigating HRV have established that hypertension is characterized by sympathetic overactivity and or attenuation of parasympathetic modulation of the heart.
  
  
  METHODS
  We examined short-term heart rate variability (HRV) as well as conventional indices of cardiovascular autonomic function including heart rate variation during deep breathing (HRVdb), 30: 15 ratio, pressor response to quiet standing and isometric handgrip in 35 male subjects (39 +/- 7 year, mean +/- SD) with new-onset hypertension (resting BP 155 +/- 17/101 +/- 8 mm Hg) and 17 age-matched normotensive men (resting BP: 111 +/- 7/71 +/- 5 mmHg).
  
  
  RESULTS
  HRVdb was significantly lower in hypertensives (21 +/- 8) compared to normotensives (mean age 36 +/- 7, P = 0.03). Differences in mean RR were insignificant, logarithm of high-frequency (HF) spectral power of RR intervals was significantly lower in hypertensives compared to normotensives in the supine position (P = 0.02).
  
  
  CONCLUSIONS
  Our data suggest that new-onset hypertension is characterized by diminished short-term HRV, possibly due to an increase in cardiovascular sympathovagal balance.
authors: Department of Physiology, Jawaharlal Institute of Postgraduate Medical Education & Research (JIPMER), Pondicherry, India. pavithranpp@gmail.com
authors: Purushothaman
authors: P
authors: Pavithran
authors: Raj
authors: R
authors: Mithun
authors: Mathew
authors: M
authors: Jomal
authors: Hanumanthappa
authors: H
authors: Nandeesha
mesh_terms: D000328:Adult; D017677:Age Distribution; D017668:Age of Onset; D001341:Autonomic Nervous System / Q000502:physiology*; D001795:Blood Pressure Determination; D016022:Case-Control Studies; D015331:Cohort Studies; D004562:Electrocardiography; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000453:epidemiology*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011187:Posture; D011336:Probability; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric