DURATION OF ABPM AS AN IMPORTANT PREREQUISITE FOR A RELIABLE DIAGNOSIS OF VASCULAR VARIABILITY DISORDERS (VVDS) L.Z. Gumarova, G. Cornelissen, F. Halberg Halberg Chronobiology Center University of Minnesota MMC 8609, 420 Delaware St. SE, Minneapolis, Minnesota, USA, 554555 A.T. Mansharipova Kazakhstan-Russian Medical University Torekulov str., 71, Almaty, Republic of Kazakhstan, 050004 K. Otsuka Daini Hospital Tokyo Women’s Medical University Medical Center East Nishiogu 2-1-10, Arakawa, Tokyo 116, Japan E.V. Syutkina Institute of Pediatrics Scientific Center for Children's Health Academy of Medical Sciences Lomonosovsky av., 2/62, Moscow, Russia, 119991 A.V. Masalov Optics Department Lebedev Physical Institute Leninsky Prospect, 53, Moscow, Russia, 119991 S.M. Chibisov, V.A. Frolov Department of Pathological Physiology People's Friendship University of Russia Miklukho-Maklaya str., 6, Moscow, Russia, 117198 ABPM records from 26 clinically healthy residents of Tosa City, Japan over 6 or 7 days were analyzed overall and day-by-day in order to determine the frequency of occurrence of vascular variability abnormalities (VVAs) and the extent of reproducibility of the results from one day to another. <...> ABPM records over 18 to 33 hours from 360 patients of a specialized cardiology clinic in Almaty (Kazakhstan) with cardiovascular diseases of medium or high severity were also analyzed. <...> Among all records from Tosa City, at least one VVA was found on at least one day in all residents. <...> Twelve subjects with no overall abnormality had VVAs in 1 to 3 days. <...> Of the remaining 14 subjects, only one had no overall abnormality but at least one VVA in 6 of 7 days. <...> The other 13 had at least one VVA in 4 or more days as well as an overall abnormal record One or more VVAs occurred in 78% of the cardiac patients in Almaty. <...> More than one type of VVA was found in 50% of the patients. <...> In 22% of cardiac patients no VVA was found, despite the fact that these patients had cardiovascular diseases. <...> The large day-to-day variability in circadian characteristics of blood pressure and heart rate observed in Tosa City and the associated presence or absence of VVA(s) on a given day indicate <...>