title: Daily environmental differences in blood pressure and heart rate variability in healthy premenopausal women.
abstract: OBJECTIVE
  As daily environments change, behavior and activity also change and as blood pressure (BP) and heart rate (HR) are allostatically tied to these factors, one might expect that environments that elicit the greatest behavioral/activity variation should also evince the highest BP and HR variability [standard deviation (SD) or coefficient of variation (CV)]. The purpose of this study was to evaluate this premise.
  
  
  METHODS
  Two hundred and six women (age = 37.6 ± 9.1 years) wore an ambulatory BP monitor on a midweek workday. All worked in clerical, technical, or professional positions. Ambulatory BP and HR Means, SDs and CVs at work (11 AM-3 PM), home (∼6-10 PM) and during sleep (∼10 PM-6 AM) were compared using repeated measures ANCOVA.
  
  
  RESULTS
  Mean BP and HR decreased from work and home to sleep [121 ± 11, 120 ± 11 vs. 107 ± 12 systolic; 82 ± 10, 80 ± 11 vs. 66 ± 11 diastolic; 79 ± 12, 80 ± 12 vs. 68 ± 11 HR (all P < 0.001)], while the CV of systolic and diastolic BP increased [0.06 ± 0.02, 0.07 ± 0.02 vs. 0.08 ± 0.03 systolic; 0.09 ± 0.03, 0.10 ± 0.04 vs. 0.12 ± 0.05 diastolic (P < 0.001)]. The HR SD decreased during sleep [8.1 ± 3.8, 8.2 ± 3.8 vs. 6.9 ± 3.2 (P < 0.001)].
  
  
  CONCLUSIONS
  HR variability follows the expected variability pattern with behavior and activity, whereas BP does not.
authors.affiliation: Department of Anthropology, Binghamton University, Binghamton, New York, 13902; Decker School of Nursing, Department of Bioengineering, Binghamton University, Binghamton, New York, 13902.
authors.forename: Gary D
authors.initials: GD
authors.lastname: James
authors.forename: Dana H
authors.initials: DH
authors.lastname: Bovbjerg
authors.forename: Leah A
authors.initials: LA
authors.lastname: Hill
mesh_terms: D000328:Adult; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D002940:Circadian Rhythm; D004777:Environment; D005260:Female; D006339:Heart Rate; D006801:Humans; D008875:Middle Aged; D009519:New York City