Reactivity as a Predictor of Subsequent Blood Pressure

Abstract

Abstract-This study investigated the association between cardiovascular reactivity and subsequent ambulatory blood pressure in 316 black and white men and women in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Cardiovascular laboratory reactivity was examined in subjects 20 to 33 years old, and ambulatory blood pressure and heart rate were measured 3 years later. Average ambulatory pressure during a 24-hour period was regressed separately on stress reactivity and standard covariate risk factors in each race/gender subgroup. Blacks had higher blood pressure and heart rates than whites, men had higher blood pressure than women, and women had higher heart rates than men. After controlling for age, baseline systolic pressure, familial history of hypertension, smoking, alcohol consumption, body mass index, and exercise, systolic blood pressure reactivity to star tracing and cold pressor stress were significantly associated with systolic ambulatory pressure in black men and women 3 years later (partial rϭ0.24 to 0.37). Heart rate reactivity to video challenge and star tracing were also significantly predictive of subsequent ambulatory heart rate in blacks. Diastolic star tracing reactivity was significantly associated with subsequent ambulatory blood pressure in black women (rϭ0.23), and diastolic reactivity to video and star tracing were significantly predictive of ambulatory diastolic pressure in white men (rϭ0.39). We conclude that hyperresponsivity to stress may be a risk factor for subsequent blood pressure elevation in blacks and may be one pathway leading to the higher prevalence of hypertension in blacks than in whites. Key Words: blood pressure Ⅲ race Ⅲ stress B lood pressure responsiveness to mental stress has been reported to be a significant predictor of exercise-induced myocardial ischemia 1 and carotid artery atherosclerosis. 2 Although it has also been reported to predict stable hypertension in borderline-hypertensive individuals, 3 its utility as a prognostic measure has been questioned, 4 and data concerning the association between stress reactivity and ambulatory blood pressure have been equivocal. 5-11 A number of these studies are difficult to interpret because they were either based solely on correlations, only examined absolute levels during reactivity, or did not control for relevant covariates. [12][13][14][15] There has been little research examining the effect of race and gender on the association between reactivity and subsequent ambulatory pressure, despite the fact that previous research has been fairly consistent in showing race as well as gender differences in reactivity and blood pressure measured at a single sitting. 16 -19 The goal of the present study was to investigate whether cardiovascular reactivity to mental stress predicted subsequent ambulatory blood pressure differently in race/gender subgroups. Ambulatory blood pressure was chosen because it better reflects blood pressure variation and levels throughout the day than clinical measurements made at a si...

The relationship between cortisol, C-reactive protein and hypertension in African and Causcasian women : the POWIRS study

“…Since the African women in this study were urbanised, one could hypothesise that this could be a possible explanation for these results 16. Specifically, the increased vascular reactivity in the hypertensive African women corresponds to previous studies that found an increased relative risk for hypertension in both Africans and African-Americans compared to other ethnic groups, due to increased measurements of cardiovascular reactivity when a specific stressor was applied 2,3,5,19-23…”

Racial Differences in Aortic Stiffness in Children

“…57 Data suggest African-American youth have greater BP reactivity compared with their white counterparts. 58-60 Racial differences in BP reactivity may be related to greater vasoconstrictor sensitivity among African-Americans, whereby increases in peripheral vascular resistance elevate BP, rather than increases in cardiac inotropy/chronotropy. 59, 61, 62 Whether racial differences in aortic stiffness contribute to cardiovascular reactivity, or vice versa, has yet to be established.…”

Effects of Nitrate Supplementation on Cardiovascular and Autonomic Reactivity in African-American Females

“…Because it characterizes the early stages of hypertension, it is speculated that such heightened pressor responsiveness to stress may be a key factor in the pathogenesis of hypertension [9–11]. Blood pressure reactivity during laboratory stressors has also been found to be more predictive of increased ambulatory blood pressure measured three years later, in African Americans compared to Caucasians [12]. In examining blood pressure responses to the physical stress of cycle ergometry in normotensive individuals, 82% of blood pressure hyperresponders developed hypertension after a two-year follow-up [13].…”