PP.18.13

Abstract

Objective: Several studies have demonstrated that prehypertension is associated with increased target organ damage involvement and cardiovascular risk compared to normotension. However, the impact of short-term blood pressure (BP) variability on target organ damage in prehypertensive subjects has never been investigated. Aim of our study was to evaluate the association of ambulatory BP variability with common carotid artery intima-media thickness (CCA-IMT) in untreated prehypertensive individuals. Design and method: A total of 291 never treated prehypertensive subjects referred for evaluation at the Hypertension Unit of our department, underwent 24-h ambulatory BP monitoring and CCA-IMT ultrasonographic measurements. Prehypertension was defined according to office BP values (120mmHg <= systolic BP < 140mmHg and 80mmHg <= diastolic BP < 90mmHg). Ambulatory BP variability was expressed by standard deviation (SD) of systolic BP and time rate (TR) of systolic BP variation. The study population was dichotomized according to the SD of systolic BP (Low SD group and High SD group) and TR of systolic BP variation levels (Low TR group and High TR group). Statistical analysis was performed by means of independent-samples T test and ANCOVA. Results: Prehypertensive subjects with high TR of systolic BP variation presented significantly (p = 0.001) greater CCA-IMT values (0.744 mm) compared to those with low TR of systolic BP variation (0.686 mm), even after adjustment for demographic characteristics and baseline risk factors. In contrast, CCA-IMT did not differ significantly between prehypertensive individuals with high (0.725 mm) and low SD (0.704 mm) of systolic BP. Conclusions: Prehypertensive subjects with increased TR of systolic BP variation present significantly higher CCA-IMT values compared to those with low TR of systolic BP variation. The assessment of ambulatory BP variability may play an important role for risk stratification of prehypertensive individuals.