PP.06.18] SEASONAL BLOOD PRESSURE CHANGES IN HIGH NORMAL, NORMAL AND OPTIMAL BLOOD PRESSURE PATIENTS WITHOUT ANTIHYPERTENSIVE MEDICATION

Abstract

Objective: Many investigators supposed that seasonal blood pressure (BP) changes are one of the reasons of fatal and nonfatal cardiovascular events. These studies included mainly the patients with arterial hypertension and the division of patients into groups with high normal (HNBP) or normal and optimal BP was not done. The aim of study was to estimate the seasonal differences in clinical (CBP) and ambulatory BP (ABP) in patients with HNBP and normal and optimal BP. Design and method: The ambulatory patients from the ABP monitoring database (>2000 patients) were selected according to the following criteria: absence of any antihypertensive treatment, availability of CBP and ABPM records in winter or summer, CBP<140 and 90 mmHg. Standard statistical methods were used. Results: The preliminary data of the on-going study are demonstrated. We selected 355 patients: 206 with HNBP and 149 with normal and optimal BP. The main characteristics of groups and seasonal BP changes are presented in Table. In patients with HNBP only systolic CBP was significantly higher in winter than in summer. We found similar tendency for ABP data in these patients despite relatively small differences. In patients with normal and optimal BP only diastolic ABP was higher in winter; in contrast, nighttime systolic BP was higher in summer. At the same time, average values of CBP and ABP in the normal and optimal BP group did not exceed threshold limits.Conclusions: Some of the ABP parameters in patients with HNBP without antihypertensive medication are increased in winter and exceed normal values. This factor may contribute to the increase of cardiovascular events incidence in winter. The problem should be studied in prospective investigations.