Differences between daytime and nighttime blood pressure variability regarding systemic atherosclerotic change and renal function

Abstract

Recently, new parameters related to hypertension, such as variability in blood pressure and ambulatory arterial stiffness index (AASI), were demonstrated to correlate with arteriosclerotic change. In this study, we investigated the correlation between circadian variability in blood pressure/AASI and renal function. We also investigated differences in the clinical impact of 24 h, daytime and nighttime blood pressure variability on renal and systemic atherosclerotic changes. We analyzed data from 120 patients who underwent renal Doppler ultrasonography (RDU) and ambulatory blood pressure monitoring (ABPM) at our hospital ward, and investigated the correlation between circadian variability in blood pressure/AASI and renal function, including resistive index (RI) evaluated with RDU, which is thought to be a good indicator of renal vascular resistance. Subjects with higher circadian variability in systolic blood pressure (SBP) had significantly higher RI. Daytime variability in SBP correlated more strongly with RI than nighttime variability. Meanwhile, only nighttime variability, but not daytime variability, in SBP was related to carotid atherosclerosis. Similarly, AASI was significantly correlated with RI. Circadian variability in SBP and AASI were both significantly correlated with renal function. Daytime SBP s.d. was especially more strongly correlated with renal vascular resistance, and nighttime SBP s.d. was significantly correlated with intima-media thickness (IMT) and plaque score. These results indicate that evaluating both daytime and nighttime blood pressure variability enables an assessment of pathological conditions in hypertensive patients to prevent cardiovascular diseases.

Relationship between arterial stiffness and variability in systolic blood pressure during a single clinic visit in patients with hypertension

“…Other studies demonstrated an association between systemic atherosclerotic change and 24-h 18,19 or visit-to-visit 20 blood pressure variability. However, there are few data about the relationship between Recently, visit-to-visit variability in SBP has been shown to be a predictor of stroke.…”

Intensive treatment of persistent microalbuminuria: determinants of treatment resistance

“…A second related parameter is the blood pressure variability. It has recently also been shown to increase cardiovascular events and it is associated to night time changes in blood pressure and the long lasting effect of antihypertensive drugs [41,42]. Nevertheless, any conclusion at this respect has an important limitation since 24h ambulatory blood pressure monitoring was not performed.…”

Predictors of blood pressure control in patients with resistant hypertension

“…In the RH patients, recovery of pathological diurnal rhythm was associated with an improved BP control (13). Moreover, non-dipping is known to be associated with the target organ damage (17), cardiovascular events and mortality (18). Nighttime BP changes were shown to have a higher prognostic value compared to the average 24 hour BP (19).…”