Is Blood Pressure Variability Related to Activity of the Sympathetic System?

Abstract

1. In 70 patients with untreated essential hypertension, blood pressure variability was correlated to plasma catecholamines and to the response of blood pressure and peripheral flow to cold pressure and handgrip tests. 2. Supine blood pressure was recorded every 5 min, during 3 h. Variability was defined as the standard deviation of the mean of the readings in that period. 3. Blood pressure variability is positively and significantly correlated to the level of pressure and to age. 4. No significant correlation could be found with plasma catecholamines and sympathetic function tests. 5. It is concluded that blood pressure variability is related to the level of pressure but not to activity of the sympathetic nerves.

Short-term variability and nocturnal decline in ambulatory blood pressure in normotension, white-coat hypertension, masked hypertension and sustained hypertension: a population-based study of older individuals in Spain

“…5 In addition, we postulate that mechanisms other than sympathetic activity are operating in white-coat hypertension, since this activity correlates with the level and standard deviation of BP, but not with the coefficient of variation, a measure of variability that is less dependent on the level of BP than the standard deviation. 40 It is noteworthy that in patients with antihypertensive treatment, we did not observe any differences in BP variability indexes. So, it is possible that antihypertensive treatment controls BP variability independent of mean BP.…”

Detection of a diurnal rhythm in arterial blood pressure in the evaluation of 24‐hour antihypertensive therapy

“…prevalence of high blood pressure values in the population, and studies evaluating the effect of health procedures and pharmaceutical preparations over a period of time to diminish such high values, must take into account the sphygmomanometer-auscultatory method, that for its simple function and extreme economy can be largely diffused, and, therefore, can also easily be standardized (Hypertension Detection and Follow-up Program Cooperative Study, 1979;Kannel, 1974;The Australian Therapeutic Trial in Mild Hypertension, 1980;Veteran's Administration Cooperative Study Group on Antihypertensive Agents, 1972). The data obtained from 24-h blood pressure continuous and semicontinuous recordings, although limited in number, have contributed more than the selfrecording system in confirming the existing different behavior of this parameter during ambulatory visits, working time, and home life (Clement et al, 1979;Perloff et al , 1982;Pickering et al, 1982;Van Maele and Clement, 1982). In subjects suspected of hypertension, the "casual" method has brought to light subgroups which have included fixed hypertensives, borderline hypertensives, normal subjects but with hyperkinetic state, and even subjects who presented a normal blood pressure profile in a 24-h recording (De Gaudemaris et al, 1983).…”

Prognosis in Relation to Blood Pressure Variability

“…sympathetic activity correlated with the level and the sD of blood pressure, but not with the coefficient of variability, a measure of variability that is less dependent on level than the sD. 29 in the 1980s, Mancia et al 30 , by analyzing continuous 24-hour intra-arterial recordings replicated the observation that sD, but not coefficient of variation, is highly dependent on the blood pressure level. nevertheless, until today, investigators continue using the sD to capture blood pressure variability.…”

“…in the early 1970s, Clement et al 29 assessed blood pressure variability from the sD and the coefficient of variation of blood pressure measurements obtained every 5 minutes for 3 hours in 70 untreated hypertensive patients. sympathetic activity correlated with the level and the sD of blood pressure, but not with the coefficient of variability, a measure of variability that is less dependent on level than the sD.…”