Heart rate variability in middle-aged men with new-onset hypertension.
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.
Pavithran
Purushothaman
P
Department of Physiology, Jawaharlal Institute of Postgraduate Medical Education & Research (JIPMER), Pondicherry, India. pavithranpp@gmail.com
Mithun
Raj
R
Jomal
Mathew
M
Nandeesha
Hanumanthappa
H
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