P-176: Impact of diurnal patterns of vascular resistance and compliance on blood pressure night fall

Underlying mechanisms of non-dipping fenomenon are under discussions in aspects of demographic and metabolic factors, daily activities, autonomic cardiovascular regulation. We aimed to investigate by means of 24-hour noninvasive pulse wave analyses possible differences in daytime and nighttime vascular hemodynamics between essential hypertensives (EH) with and without sufficient nighttime BP fall. Ninenteen randomly selected untreated verified EH (11 males; aged (mean±SD) 37.9± 9.4 years; daytime SBP 156.1±15.3, daytime DBP 90.3±9.9 mmHg) underwent 24 hour ambulatory oscillometric BP and HR measurements (DynaPulse 5000A; Pulse Metric, Inc., USA) with systemic vascular (SV) and brachial artery compliance and resistance evaluation at each measurement by the previously validated pulse dynamics analysis technology. The vascular hemodynamics variables were compared between dippers (10 subjects) and non-dippers (9 subjects).In the sample investigated non-dippers were significantly older then dippers (44.4±5.8 vs. 32.0±8.2 years; p