Ambulatory blood pressure, blood pressure variability and the prevalence of carotid artery alteration: the Ohasama study

J Hypertens. 2007 Aug;25(8):1704-10. doi: 10.1097/HJH.0b013e328172dc2e.


Objectives: To investigate the association between ambulatory blood pressure (BP) variables (level, short-term variability, circadian variation and morning pressor surge) and carotid artery alteration in a general population.

Methods: We measured ambulatory BP every 30 min in 775 participants (mean age 66.2 +/- 6.2 years, 68.8% women) from the Japanese general population. Short-term BP variability during the daytime and night-time were estimated as within-subject standard deviation of daytime and night-time BP, respectively. Circadian BP variation was calculated as the percentage decline in nocturnal BP. Morning pressor surge was defined as morning BP minus pre-waking BP. The extent of carotid artery alteration was evaluated as the average of common carotid intima-media thickness (IMT) and the presence of focal carotid plaque.

Results: Daytime and night-time BP values were more closely associated with carotid artery alteration than casual BP. With mutual adjustment for daytime and night-time BP, the latter (P < 0.0001) was more closely associated with IMT, which represents diffuse arterial thickening and arteriosclerosis, than daytime BP (P = 0.2). Night-time systolic BP variability was positively associated with carotid plaque (focal atherosclerotic lesions) independently of possible confounding factors, including night-time systolic BP (P = 0.01). A diminished nocturnal decline in systolic BP was associated with a greater IMT after adjustment for confounding factors (P = 0.03). A morning pressor surge was not associated with carotid artery alteration.

Conclusion: Ambulatory BP levels and BP variability were closely associated with carotid artery alteration, suggesting that these parameters are independent risk factors or predictors of carotid artery alteration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Blood Pressure*
  • Carotid Arteries / diagnostic imaging
  • Carotid Arteries / physiology*
  • Cross-Sectional Studies
  • Female
  • Humans
  • Male
  • Middle Aged
  • Prevalence
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Ultrasonography