title: Impaired baroreflex sensitivity and the risks of new-onset ambulatory hypertension, in an elderly population-based study.
abstract: BACKGROUND
  Impairment of the autonomic nervous system activity may be involved in the development of hypertension. Yet the prognostic values of heart rate variability and baroreflex sensitivity in the risk of new-onset ambulatory hypertension have not been investigated. We sought to assess the relationship between heart rate variability and baroreflex sensitivity parameters and ambulatory hypertension in a community-dwelling elderly cohort.
  
  
  METHODS
  Normotensive subjects were selected from the PROOF study cohort, including 1011 subjects aged 65 years at baseline. The autonomic nervous system activity was assessed through 24-hour heart rate variability and 15-minute spontaneous baroreflex sensitivity at baseline. Incident hypertension was defined with the 24-hour, day-time and night-time ambulatory blood pressure measurements and antihypertensive treatment use, at two-years of follow-up.
  
  
  RESULTS
  At baseline, 13.7% of subjects developed day-time hypertension, 18.2% developed night-time hypertension and 13.6% developed 24-hour hypertension. Reduced baroreflex sensitivity at baseline was associated with onset of hypertension after adjustment for blood pressure level, C-reactive protein levels and depression score (OR = 0.45 [0.23-0.86]). Indices of heart rate variability were not associated with hypertension onset.
  
  
  CONCLUSIONS
  Baroreflex sensitivity may represent an intermediate goal for prevention of ambulatory hypertension at early stage.
authors.affiliation: Memory Research Center Lyon, Hôpital des Charpennes, Hospices Civils de Lyon, University Medical Hospital, Lyon, France. Electronic address: d_virginie@hotmail.com.
authors.forename: Virginie
authors.initials: V
authors.lastname: Dauphinot
authors.forename: Michel P
authors.initials: MP
authors.lastname: Kossovsky
authors.forename: François
authors.initials: F
authors.lastname: Gueyffier
authors.forename: Vincent
authors.initials: V
authors.lastname: Pichot
authors.forename: Philippe
authors.initials: P
authors.lastname: Gosse
authors.forename: Frédéric
authors.initials: F
authors.lastname: Roche
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Barthélémy
mesh_terms: D000368:Aged; D017704:Baroreflex / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance / Q000379:methods*; D011446:Prospective Studies; D012307:Risk Factors
keywords: Aging; Autonomic nervous system; Baroreflex sensitivity; Cardiovascular risk factors; Hypertension