Circadian hemodynamics in men and women with high blood pressure: dipper vs. nondipper and racial differences.

Journal Article (Journal Article)

OBJECTIVE: The 'nondipping' pattern of circadian blood pressure (BP) variation is an established independent predictor of adverse cardiovascular outcomes. Although this phenomenon has been widely studied, its underlying circadian hemodynamics of cardiac output and systemic vascular resistance (SVR) have not been well characterized. We evaluated the hypothesis that BP nondipping would be associated with a blunted night-time reduction in SVR in a biracial sample of 140 (63 African-American and 77 white) men and women with elevated clinic BP (130-159/85-99 mmHg). METHODS AND RESULTS: Twenty-four-hour ambulatory hemodynamics were assessed using standard ambulatory BP monitoring coupled with synchronized ambulatory impedance cardiography. Using the criterion of less than 10% dip in SBP, there were 51 nondippers (SBP dip = 7.3 ± 2.6%) and 89 dippers (SBP dip = 15.5 ± 3.4%). There was minimal change in cardiac output from daytime to night-time in both dippers and nondippers. However, SVR decreased from daytime to night-time, but nondippers compared with dippers exhibited a significantly attenuated decrease in SVR from daytime to night-time (7.8 vs. 16.1%, P < 0.001). Relative to their white counterparts, African-Americans also exhibited blunted SBP dipping (10.9 vs. 14.6%, P < 0.001) as well as an attenuated decrease in SVR (10.8 vs. 15.6%, P < 0.001). CONCLUSION: Overall, these findings indicate that blunted night-time BP dipping is associated with impairment of the systemic vasodilation that is characteristic of the night-time sleep period and is especially prominent among African-Americans. In the context of high BP, these findings suggest that nondipping may be a manifestation, or marker, of more advanced vascular disease.

Full Text

Duke Authors

Cited Authors

  • Sherwood, A; Hill, LK; Blumenthal, JA; Hinderliter, AL

Published Date

  • February 2018

Published In

Volume / Issue

  • 36 / 2

Start / End Page

  • 250 - 258

PubMed ID

  • 28902662

Pubmed Central ID

  • PMC5845765

Electronic International Standard Serial Number (EISSN)

  • 1473-5598

Digital Object Identifier (DOI)

  • 10.1097/HJH.0000000000001533


  • eng

Conference Location

  • England