title: Reproducibility of dipping/nondipping pattern in untreated essential hypertensive patients: impact of sex and age.
abstract: OBJECTIVE
  We aimed to evaluate the intrasubject short-term reproducibility of nocturnal blood pressure patterns (dipping/nondipping) in essential hypertensive patients in relation to age (<50 and > or =50 years) and sex.
  
  
  METHODS
  A total of 619 never-treated essential grade 1 and 2 hypertensive patients (383 men, 236 women) underwent the following procedures: (1) repeated clinic blood pressure measurements, (2) routine examinations, (3) ambulatory blood pressure monitoring over two 24-h periods within 4 weeks. Dipping pattern was defined as a 10%, or more, reduction in average systolic blood pressure/ diastolic blood pressure at night compared to daytime values.
  
  
  RESULTS
  Of the 407 patients showing a dipping pattern during the first ambulatory blood pressure monitoring period, 329 (80.1%) had the same pattern during the second ambulatory blood pressure monitoring recording. Of the 212 patients with a nondipping pattern during the first ambulatory blood pressure monitoring period, 140 (65.9%) confirmed the same pattern during the second ambulatory blood pressure monitoring period. Overall, 149 patients (24.1%) changed their initial nocturnal pattern at the second ambulatory blood pressure monitoring recording, without significant age and sex-related differences. Lower reproducibility rates of the nondipping as compared to the dipping pattern were found in the whole population as well as in men regardless of age and in younger but not in older women.
  
  
  CONCLUSIONS
  These findings indicate that nocturnal blood pressure patterns have a limited short-term reproducibility in the whole study population as well as in different age and sex subgroups. As variability of nocturnal blood pressure patterns is not predicted by easy available clinical data, such as sex and age, a reliable classification of patients according to circadian blood pressure patterns should be obtained by repeating ambulatory blood pressure monitoring.
authors.affiliation: Department of Clinical Medicine, Prevention and Applied Biotechnologies, University of Milano-Bicocca, Milan, Italy. cesare.cuspidi@unimib.it
authors.forename: Cesare
authors.initials: C
authors.lastname: Cuspidi
authors.forename: Stefano
authors.initials: S
authors.lastname: Meani
authors.forename: Cristiana
authors.initials: C
authors.lastname: Valerio
authors.forename: Carla
authors.initials: C
authors.lastname: Sala
authors.forename: Veronica
authors.initials: V
authors.lastname: Fusi
authors.forename: Meilikemu
authors.initials: M
authors.lastname: Masaidi
authors.forename: Alberto
authors.initials: A
authors.lastname: Zanchetti
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Mancia
mesh_terms: D000328:Adult; D017677:Age Distribution; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D015203:Reproducibility of Results; D017678:Sex Distribution