title: Effect of aging on the prognostic significance of ambulatory systolic, diastolic, and pulse pressure in essential hypertension.
abstract: BACKGROUND
  This study compared the relative prognostic significance of 24 hour intra-arterial ambulatory systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and pulse pressure (PP) parameters in middle-aged versus elderly hypertensives.
  
  
  RESULTS
  A total of 546 subjects aged <60 years and 142 subjects aged >/=60 years who had undergone baseline pretreatment 24-hour intra-arterial ambulatory blood pressure monitoring were followed for 9.2+/-4.1 years. Multivariate analysis showed that in younger subjects, 24-hour, daytime, and nighttime DBP, MAP, and SBP, when considered individually, were positively related to morbid events; DBP parameters provided the best predictive values. In the group >/=60 years (elderly group), 24-hour, daytime, and nighttime PP and SBP were the most predictive parameters, whereas ambulatory DBP and MAP measurements failed to provide any prognostic value. When 24-hour values of SBP and DBP were jointly included in the baseline model, DBP (z=2.02, P=0.04) but not SBP (z=-0.43, P=0.67) was related to outcome in younger subjects, whereas in the elderly group, SBP (z=3.33, P=0.001) was positively and DBP (z=-1.75, P=0.07) was negatively related to outcome. Clinic blood pressure measurements failed to provide any independent prognostic value in either age group.
  
  
  CONCLUSIONS
  The relative prognostic significance of ambulatory blood pressure components depends on age; DBP parameters provided the best prognostic value in middle-aged individuals, whereas PP parameters were the most predictive in the elderly. This may reflect differing underlying hemodynamic mechanisms of hypertension in these age groups.
authors.affiliation: Department of Cardiovascular Medicine, Northwick Park and St. Mark's Hospital NHS Trust and Institute for Medical Research, Harrow, Middlesex, United Kingdom.
authors.forename: R S
authors.initials: RS
authors.lastname: Khattar
authors.forename: J D
authors.initials: JD
authors.lastname: Swales
authors.forename: C
authors.initials: C
authors.lastname: Dore
authors.forename: R
authors.initials: R
authors.lastname: Senior
authors.forename: A
authors.initials: A
authors.lastname: Lahiri
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000375:Aging; D044466:Asian People; D044383:Black People; D001794:Blood Pressure; D001916:Brachial Artery; D002404:Catheterization; D015331:Cohort Studies; D003710:Demography; D003971:Diastole; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D015996:Survival Rate; D013599:Systole; D044465:White People