Abstract 16031: Effects of Nocturnal Hypertension on Arterial Stiffness and Urinary Albumin Excretion in Dipper Hypertensives: Absolute Nocturnal BP Values over and Beyond Dipping Status
Introduction: Both blood pressure (BP) non-dipping and nocturnal hypertension have been associated with accelerated target organ damage (TOD) in hypertension. However the combination of a dipping profile of circadian BP variation with increased absolute nocturnal BP values has never been investigated as regards TOD.
Hypothesis: We investigated whether nocturnal hypertensive compared to nocturnal normotensive dipper hypertensives exhibit higher values of indices of vascular and kidney damage and whether nighttime, as compared to daytime, BP is a stronger determinant of arterial stiffness and microalbuminuria.
Methods: We studied 402 subjects with stage I -II, newly diagnosed essential hypertension. According to two 24h ambulatory BP recordings 127 dipper subjects were selected and subdivided in nighttime hypertensives (NH, n=75) (nighttime BP ≥120/70) and nighttime normotensives (NN, n=52) (nighttime BP <120/70mmHg). All the participants underwent echocardiographic examination, pulse wave velocity (PWV), albumin to creatinine ratio (ACR), metabolic profile and high sensitivity C- reactive protein (hs-CRP) assessment.
Results: NH compared to NN dippers had higher log10(c-f PWV) (0.92± 0.07 vs 0.87±0.05 m/s p<0.001), higher log10(ACR) values (1.20± 0.50 vs 1.02±0.27 mg/g, p=0.01) and log10(hs- CRP) levels (0.32± 0.33 vs 0.012±0.29 mg/l, p<0.001). Nighttime compared to daytime and 24h systolic BP was correlated to a higher degree with c-f PWV, while it outweighed daytime BP as an ACR prognosticator.
Conclusions: Nighttime BP is associated more closely with c-f PWV, compared to daytime and 24h BP, as well as with ACR when compared to daytime BP. Greater values of c-f PWV and hs-CRP imply that a greater cardiovascular risk could be attributed to nocturnal hypertensive dippers as compared to their nocturnal normotensive counterparts.
- © 2010 by American Heart Association, Inc.