Diastolic Blood Pressure Reactivity Research Articles

Subliminal activation of social ties moderates cardiovascular reactivity during acute stress.

The quality of one's personal relationships has been reliably linked to important physical health outcomes, perhaps through the mechanism of physiological stress responses. Most studies of this mechanism have focused on whether more conscious interpersonal transactions influence cardiovascular reactivity. However, whether such relationships can be automatically activated in memory to influence physiological processes has not been determined. The primary aims of this study were to examine whether subliminal activation of relationships could influence health-relevant physiological processes and to examine this question in the context of a more general relationship model that incorporates both positive and negative dimensions. We randomly assigned participants to be subliminally primed with existing relationships that varied in their underlying positivity and negativity (i.e., indifferent, supportive, aversive, ambivalent). They then performed acute psychological stressors while cardiovascular and self-report measures were assessed. Priming negative relationships was associated with greater threat, lower feelings of control, and higher diastolic blood pressure reactivity during stress. Moreover, priming relationships high in positivity and negativity (ambivalent ties) was associated with the highest heart rate reactivity and greatest respiratory sinus arrhythmia decreases during stress. Exploratory analyses during the priming task itself suggested that the effects of negative primes on biological measures were prevalent across tasks, whereas the links to ambivalent ties was specific to the subsequent stressor task. These data highlight novel mechanisms by which social ties may impact cardiovascular health, and further suggest the importance of incorporating both positivity and negativity in the study of relationships and physical health.

Blood Pressure Reactions to Acute Mental Stress and Future Blood Pressure Status

To test the reactivity hypothesis using blood pressure data collected 12 years after baseline. This study examined whether blood pressure reactions to acute mental stress predicted future blood pressure resting levels, as well as the temporal drift in resting blood pressure, and whether the prediction was affected by sex, age, and socioeconomic status. Resting blood pressure was recorded at an initial baseline and in response to a mental stress task. Twelve years later, resting blood pressure was again assessed. Data were available for 1196 participants (645 women, 551 men), comprising, at the time of stress testing, 439 who were aged 24 years; 503, aged 44; and 254, aged 63. The participants included 531 who were from manual occupational households and 661 from nonmanual occupational households. In multivariate linear regression models, adjusting for a number of potential confounders, systolic blood pressure (SBP) reactivity positively predicted future resting SBP, as well as the upward drift in SBP over the 12 years (β = 0.10, p < .001 in both cases). The effect sizes were smaller than those reported from an earlier 5-year follow-up. The analogous associations for diastolic blood pressure reactivity were not statistically significant. In multivariate logistic regression, high SBP reactivity was associated with an increased risk of being hypertensive 12 years later (odds ratio = 1.03, 95% confidence interval = 1.01-1.04, p < .001). The present findings that greater reactivity is associated with higher future resting blood pressure, more upward drift in resting blood pressure, and future hypertension provide support for the reactivity hypothesis.

Gender differences and the relationships of perceived background stress and psychological distress with cardiovascular responses to laboratory stressors

The primary aim of this study was to evaluate the relationships of perceived background stress and self-reported psychological distress on cardiovascular reactivity during acute laboratory stressors. The Perceived Stress Scale (PSS) was used as the measure of perceived background stress, and the General Health Questionnaire (GHQ) was used as the measure of psychological distress. A secondary aim was to examine whether background stress and psychological distress affected the susceptibility to induction of a negative mood using music. Heart rate (HR) and blood pressure (BP) were measured in 149 female and male college students at rest and during a stressful mental arithmetic (MA) task and a mood induction procedure. Higher scores on the GHQ were associated with lower systolic BP reactivity during the MA task by all participants. Higher scores on the PSS and GHQ were also associated with lower diastolic BP and HR reactivity, but only in females. Thus, higher self-reports of background stress and psychological distress tended to result in blunted reactivity to an acute laboratory challenge. Higher levels of background stress and psychological distress were not associated with greater susceptibility to a negative mood induction. This study adds to the growing literature indicating that potentially negative health outcomes may be associated with diminished cardiovascular reactivity under certain conditions.

Hypertension Impairs Vascular Reactivity in the Pediatric Brain

Chronic hypertension impairs cerebrovascular regulation in adults, but its effects on the pediatric population are unknown. The objective of this study was to investigate cerebrovascular abnormalities in hypertensive children and adolescents. Sixty-four children and adolescents aged 7 to 20 years underwent transcranial Doppler examinations of the middle cerebral artery at the time of rebreathing CO2. Time-averaged maximum mean cerebral blood flow velocity and end-tidal CO2 were used to quantify cerebrovascular reactivity during hypercapnia. Patients were clinically categorized as hypertensive, prehypertensive, or white coat hypertensive based on 24-hour ambulatory blood pressure measurements. Their reactivities were compared with 9 normotensive control subjects and evaluated against baseline mean blood pressure z-scores and loads. Untreated hypertensive children had significantly lower hypercapnic reactivity than normotensive children (2.556 +/- 1.832 cm/s x mm Hg versus 4.256 +/- 1.334 cm/s x mm Hg, P < 0.05). Baseline mean diastolic blood pressure z-scores (r = -0.331, P = 0.037) and diastolic blood pressure loads (r = -0.351, P = 0.026) were inversely related to reactivity. Untreated hypertensive children and adolescents have blunted reactivity to hypercapnia, indicating deranged vasodilatory reactivity. The inverse relationship between diastolic blood pressure indices and reactivity suggests that diastolic blood pressure may be a better predictor of cerebral end organ damage than systolic blood pressure.

Stress-induced cardiovascular reactivity and atherogenesis in adolescents

ObjectiveTo examine the association between cardiovascular reactivity to a set of psychological stressors and carotid artery intima-media thickness, a marker of subclinical cardiovascular disease in healthy adolescents. MethodsParticipants were 25 boys and 23 girls age 14.2±0.9 years who were measured for heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure reactivity to mirror-tracing, reaction time, speech preparation and ad lib speech tasks and for common carotid artery intima-media thickness. Sequential regression analyses were used to establish the incremental increase in R2(Rinc2) for the prediction of intima-media thickness due to cardiovascular reactivity independent of age, BMI percentile, sex, socioeconomic status, and resting HR or BP. ResultsSBP reactivity while preparing (β=0.0019, Rinc2=0.09) and giving the speech (β=0.0014, Rinc2=0.10) and an aggregate reactivity score based on all 4 tasks (β=0.0026, Rinc2=0.11) independently predicted (p≤0.05) mean carotid artery intima-media thickness. Neither DBP reactivity nor HR reactivity during any task were independent predictors of intima-media thickness. ConclusionStress-induced cardiovascular reactivity, and especially SBP reactivity, is associated with carotid intima-media thickness and the early pathogenesis of cardiovascular disease. The use of an aggregate stress reactivity index provides a more reliable reflection of trait SBP reactivity to psychological stress and increases the confidence that youth with greater cardiovascular stress reactivity may indeed have greater progression of subclinical cardiovascular disease.

Pre-pregnancy stress reactivity and pregnancy outcome

Stress has been proposed as a cause of preterm birth (PTB) and small-for-gestational age (SGA), but stress does not have the same effects on all women. It may be that a woman's reaction to stress relates to her pregnancy health, and previous studies indicate that higher reactivity is associated with reduced birthweight and gestational age. The objective of this study was to examine the relationship between pre-pregnancy cardiovascular reactivity to stress and pregnancy outcome. The sample included 917 women in the Coronary Artery Risk Development in Young Adults Study who had cardiovascular reactivity measured in 1987-88 and at least one subsequent singleton livebirth within an 18-year period. Cardiovascular reactivity was measured using a video game, star tracing and cold pressor test. Gestational age and birthweight were based on the women's self-report, with PTB defined as birth <37 weeks' gestation and SGA as weight <10th percentile for gestational age. Linear and Poisson regression and generalised estimating equations were used to model the relationship between reactivity to stress and birth outcomes with control for confounders. Few associations were seen between reactivity and pregnancy outcomes. Higher pre-pregnancy diastolic blood pressure (adjusted relative risk 1.14; 95% confidence interval [CI] 0.98, 1.34) and mean arterial pressure reactivity (1.15; 0.98, 1.36) were associated with risk of PTB at first pregnancy, while SGA was associated with lower systolic blood pressure reactivity (0.76; 0.60, 0.95). No associations were seen with other measures of reactivity. Contrary to hypothesis, the association between heart rate reactivity and PTB in first pregnancy was stronger in whites (adjusted relative risk 1.39; 1.03, 1.88) than in blacks (1.00; 0.83, 1.20; P for interaction = 0.08). Similar results were found for mean arterial pressure. No strong associations were found between higher pre-pregnancy stress reactivity and SGA or PTB, and stress reactivity did not have a stronger association with birth outcomes in blacks than whites.

Serum calcium revisited: associations with 24-h ambulatory blood pressure and cardiovascular reactivity in Africans

Sub-Saharan Africans face an increasing burden of hypertension. Although controversial, recent experimental evidence strongly suggests that serum calcium contributes to elevated blood pressure through increased vascular resistance. We investigated the associations of 24-h blood pressure and cardiovascular reactivity with serum calcium in African men stratified by age. The study consisted of 50 younger (median age: 38 years) and 49 older (median age: 49 years) participants. We measured 24-h ambulatory blood pressure with a mean successful inflation rate of 72.6%. Total peripheral resistance and stroke volume reactivity were obtained using a Finometer device during application of the Stroop color and word conflict test. Total serum calcium was adjusted for serum albumin. Results showed that serum calcium levels were similar between the younger and older groups. However, in the younger group, 24-h systolic blood pressure, 24-h diastolic blood pressure and total peripheral resistance reactivity correlated positively, whereas stroke volume reactivity correlated negatively with serum calcium in single and multiple regression analyses (systolic blood pressure: B=34.99, P=0.017; diastolic blood pressure: B=34.93, P<0.001; total peripheral resistance reactivity: B=65.44, P=0.048; stroke volume reactivity: B=-45.40, P=0.017). No associations were evident in the older African men. In conclusion, 24-h ambulatory systolic and diastolic blood pressures are positively associated with serum calcium in African men younger than 43 years. The blood pressure-serum calcium relationship seems to be mediated through increased vascular resistance during stress.

Beta-adrenergic receptor gene polymorphisms and cardiovascular reactivity to stress in Black adolescents and young adults.

Cardiovascular reactivity to stress and beta-adrenergic receptor (beta-AR) function may contribute to the development of hypertension. As Black Americans have an increased risk of hypertension, we evaluated associations between beta(1)-AR (Arg389Gly) and beta(2)-AR (Arg16Gly, Gln27Glu) gene variants and cardiovascular reactivity in 500 Black youth. Heart rate, preejection period, total peripheral resistance, and blood pressure reactivity were measured during cold and psychological stress. The Arg389Gly polymorphism in the beta(1)-AR was associated with preejection period reactivity in males but not in females. The Arg16Gly polymorphism in the beta(2)-AR was associated with diastolic blood pressure reactivity only during video game stress. An association between the Gln27Glu polymorphism in the beta(2)-AR and vascular reactivity depended on sex. Thus, specific patterns of associations emerged between genetic variations in beta-ARs and cardiovascular reactivity in young Blacks.

Depression and anxiety: Associations with biological and perceived stress reactivity to a psychological stress protocol in a middle-aged population

Depression and anxiety have been linked to higher as well as lower reactivity to stressful circumstances. Large, population-based studies investigating the association between depression and anxiety, perceived and physiological stress responses are lacking. We studied 725 men and women, aged 55-60 years, from a population-based cohort, who filled out the Hospital Anxiety and Depression Scale (HADS). We performed a standardized interview on medical history and lifestyle. We measured continuous blood pressure (BP) and heart rate (HR) reactivity, saliva cortisol reactivity and perceived stress during a psychological stress protocol. Albeit not statistically significant in all groups, systolic BP (SBP), diastolic BP (DBP), HR and cortisol reactivity to the psychological stress protocol were lower in those with mild-to-severe depression or anxiety symptoms and those ever clinically diagnosed with depression or anxiety, while perceived levels of stress were higher compared to those without depression or anxiety symptomatology. Maximum SBP, HR and cortisol stress responses significantly decreased and perceived stress scores significantly increased with increasing scores on the HADS depression subscale (HADS-D) and HADS anxiety subscale (HADS-A) (all P<0.05). The same held for stress responses in relation to the total HADS score (all P<0.05) and, in this case, the maximum DBP stress response was also significantly lower with an increasing HADS score (P=0.05). In addition, the maximum DBP stress response was significantly lower for those ever clinically diagnosed with depression (P=0.04). Adjusting for sex, use of anti-hypertensive medication, anti-depressant and anxiolytic medication, smoking, alcohol consumption, socio-economic status (SES) and body mass index (BMI) did not attenuate the results. The present study results suggest that the biological stress response of middle-aged men and women who experienced depressed and anxious feelings does not completely correspond with how stressed they feel at that moment. Although differences were not substantial in all cases, response to a psychological stress protocol seemed to be decreased in the groups with experience of depressed and anxious feelings, while the perception of stress seemed to be increased.

Hostility and physiological responses to laboratory stress in acute coronary syndrome patients

ObjectiveEvidence suggests that emotional stress can trigger acute coronary syndromes in patients with advanced coronary artery disease (CAD), although the mechanisms involved remain unclear. Hostility is associated with heightened reactivity to stress in healthy individuals, and with an elevated risk of adverse cardiac events in CAD patients. This study set out to test whether hostile individuals with advanced CAD were also more stress responsive. MethodsThirty-four men (aged 55.9±9.3 years) who had recently survived an acute coronary syndrome took part in laboratory testing. Trait hostility was assessed by the Cook Medley Hostility Scale, and cardiovascular activity, salivary cortisol, and plasma concentrations of interleukin-6 were assessed at baseline, during performance of two mental tasks, and during a 2-h recovery. ResultsParticipants with higher hostility scores had heightened systolic and diastolic blood pressure (BP) reactivity to tasks (both P<.05), as well as a more sustained increase in systolic BP at 2 h post-task (P=.024), independent of age, BMI, smoking status, medication, and baseline BP. Hostility was also associated with elevated plasma interleukin-6 (IL-6) levels at 75 min (P=.023) and 2 h (P=.016) poststress and was negatively correlated with salivary cortisol at 75 min (P=.034). ConclusionHostile individuals with advanced cardiovascular disease may be particularly susceptible to stress-induced increases in sympathetic activity and inflammation. These mechanisms may contribute to an elevated risk of emotionally triggered cardiac events in such patients.

Chronic Life Stress, Cardiovascular Reactivity, and Subclinical Cardiovascular Disease in Adolescents

To examine cross-sectional and longitudinal relationships between chronic life stress, cardiovascular reactivity, and a marker of subclinical cardiovascular disease in a multiethnic sample of adolescents. Participants were 158 healthy adolescents who completed self-report measures of chronic negative life stress as well as assessments of heart rate and blood pressure reactivity to acute laboratory stressors at two time points, approximately 3.3 years apart. At Time 2, intima-media thickness (IMT), a measure of subclinical atherosclerosis, was also measured. In hierarchical regression models adjusting for demographic variables and body mass index, chronic negative life stress at Time 2 was concurrently associated with greater diastolic blood pressure (DBP) reactivity to stress (beta = 0.18, p = .016), but neither chronic stress nor cardiovascular reactivity was associated concurrently with IMT. Increasing life stress from Time 1 to Time 2 was accompanied by increasing cardiovascular reactivity (beta = 0.14-0.20, p < .05), and increasing DBP reactivity over time was also associated with IMT (beta = 0.24, p = .03), although increasing chronic life stress was not directly related to IMT. Adolescents exposed to chronic, negative stressors that worsen over time may show heightened cardiovascular reactivity that puts them at risk for subclinical atherosclerosis.

Social ties and cardiovascular function: An examination of relationship positivity and negativity during stress

The quality and quantity of one's relationships have been reliably linked to morbidity and mortality. More recently, studies have focused on links between relationships and cardiovascular reactivity as a physiological mechanism via the stress-buffering hypothesis. However, not all social relationships are consistently positive which points to the importance of a more comprehensive examination of relationship that includes negative qualities. In this study, we manipulated relationship positivity and negativity with an experimenter and examined its influence on cardiovascular reactivity. Results revealed that relationship positivity was associated with lower systolic blood pressure (SBP) reactivity for men and women. Relationship negativity, on the other hand, was related to less of an increase in diastolic blood pressure (DBP) reactivity in men. Internal analyses showed that perceptions of positivity and negativity interacted such that high positivity/high negativity perceptions (ambivalence) were related to the highest SBP reactivity. Results of this study suggest that the quality of one's relationships is an important moderator of cardiovascular reactivity during stress.

Protective effect of interval exercise on psychophysiological stress reactivity in children

Two studies determined whether interval exercise reduces children's stress reactivity. For Experiment 1 children completed interval exercise (n=14) or watched TV (n=14) for 25 min. After 20 min rest children completed a speech task. Speech-induced diastolic blood pressure (DBP) reactivity was dampened in the exercise group (p<.05). For Experiment 2 children (n=22) completed interval exercise-speech and TV-speech conditions on separate days. Physical activity was assessed by accelerometry and aerobic fitness estimated by submaximal exercise. DBP, systolic BP, and heart rate (HR) reactivity to the speech stressor were dampened (p<.05) after exercise compared to TV watching. Fitness was positively associated with HR reactivity. Interval exercise that mimics usual patterns of physically active play dampens cardiovascular reactivity to interpersonal stress.

Positive affect is associated with cardiovascular reactivity, norepinephrine level, and morning rise in salivary cortisol

Positive affect was examined as a predictor of (1) cardiovascular reactivity during a sadness and an anger recall task and recovery following the protocol, (2) epinephrine (EPI) and norepinephrine (NOREPI) reactivity and level during the recall protocol, and (3) the diurnal pattern of salivary cortisol. Sample was 328 individuals. Negative affect, age, race, sex, smoking status, income, and BMI were adjusted. During sadness recall, positive affect was inversely related to systolic blood pressure (p=.007) and diastolic blood pressure (p=.049) reactivity, and unrelated to heart rate (p=.226). Positive affect was unrelated to reactivity during anger recall (ps>.19), and was unrelated to recovery at the end of the recall protocol. Positive affect was inversely related to the mean level of NOREPI (p=.046), and unrelated to EPI (p=.149). Positive affect was inversely related to the increase in cortisol 30 min post awakening (p=.042), and unrelated to the evening decline in cortisol levels (p=.174). Positive emotions may be relevant to good health.

Heightened Resting Neural Activity Predicts Exaggerated Stressor-Evoked Blood Pressure Reactivity

Individuals who express relatively large-magnitude or "exaggerated" blood pressure (BP) reactions to behavioral stressors are presumably at increased risk for cardiovascular disease. As shown by recent neuroimaging studies, individuals who express exaggerated stressor-evoked BP reactivity also express heightened neural activity in corticolimbic brain areas that centrally regulate the cardiovascular system. These studies, however, have exclusively examined BP reactivity and concomitant neural activity during stressor exposure. If exaggerated BP reactivity originates in part from a centrally regulated and dispositional cardiovascular response tendency, then heightened resting (prestressor) corticolimbic activity may predict the subsequent expression of exaggerated stressor-evoked BP reactivity. To test this hypothesis, perfusion MRI was used to quantify resting regional cerebral blood flow (an indirect metabolic measure of neural activity) in men (n=19) and women (n=20) aged 20 to 37 years who subsequently performed cognitive stressor tasks to evoke BP reactivity. Individuals who expressed larger task-induced rises in systolic and diastolic BP also expressed higher resting regional cerebral blood flow in 4 functionally related corticolimbic areas: the dorsal and perigenual anterior cingulate, medial prefrontal, and insular cortices. Specifically, resting regional cerebral blood flow in these areas accounted, respectively, for 40% and 31% of the variance in systolic (P=0.001) and diastolic (P=0.008) BP reactivity, after accounting for total resting cerebral blood flow, resting BP, task performance, and task-related ratings of unpleasantness, arousal, and perceived psychological control. Heightened resting corticolimbic activity may represent a neurobiological correlate of an individual's predisposition for exaggerated stressor-evoked BP reactivity and possibly related cardiovascular risk.

Cardiovascular reactivity to psychological stress and carotid intima‐media thickness in children

The relationship between cardiovascular stress reactivity and carotid artery intima-media thickness (IMT) has been established in adults, but not yet studied in children. Cardiovascular reactivity to an ad lib speech was measured in 20 boys and 20 girls age 11.0 +/- 1.4 years. Measures included heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure reactivity, and mean common carotid artery IMT. Sequential regression analyses were used to establish the incremental increase in R(2) for the prediction of IMT due to cardiovascular reactivity independent of age, socioeconomic status, race, percentage body fat, and baseline BP or HR. SBP reactivity (beta=0.002, , p<.05), but not DBP reactivity (p=.12) or HR reactivity (p=.82), independently predicted carotid artery IMT. This study provides initial evidence that SBP reactivity is associated with IMT and perhaps the early pathogenesis of cardiovascular disease in childhood.

Hostility and anger in: Cardiovascular reactivity and recovery to mental arithmetic stress

Background Hostility and anger have been attributed as psychosocial risk factors for coronary heart disease. Heightened cardiovascular reactivity (CVR), and poor recovery, to provocative stressors are thought to hasten this risk. Purpose To examine the relationship between hostility and anger inhibition (AI), and the moderating situational influences of harassment and evaluation, in predicting CVR and recovery to mental arithmetic (MA) stress using a multiple regression approach. Methods 48 male undergraduate students engaged in the following 3 minute tasks during recording of the electrocardiogram, impedance cardiography, and blood pressure: baseline, MA, and evaluation. Hostility and AI were assessed with the Cook-Medley Hostility Scale and the Speilberger Anger In subscale, respectively. Results An interaction between hostility and AI showed high diastolic blood pressure reactivity to the MA task among hostile anger inhibitors. Harassment did not modify this effect. However, harasser evaluation predicted prolonged systolic blood pressure (SBP) responding among men scoring high in AI, and facilitated SBP recovery among those scoring low on AI. Conclusions The findings highlight the interactive influences of AI and hostility in predicting CVR to stress and underscore the importance of recovery assessments in understanding the potentially pathogenic associations of these constructs.

Blood pressure reactivity and cognitive function in the Baltimore Longitudinal Study of Aging.

Several blood pressure indexes of autonomic dysregulation, including stress-induced blood pressure responses (i.e., reactivity), have been associated previously with stroke, silent cerebrovascular disease, and decreased cognitive function. The authors examined the cross-sectional relations among systolic blood pressure (SBP) and diastolic blood pressure (DBP) reactivity and cognitive function in a sample of stroke- and dementia-free older adults (n = 73, 53% male, 72% Caucasian, mean age = 70.14 years) from the Baltimore Longitudinal Study of Aging. Age, education, baseline, and reactive blood pressure levels were regressed on cognitive test scores measuring the domains of attention, learning and memory, verbal functions/language skills, and perceptuo-motor speed. A Bonferroni correction was employed and results significant at the standard p < .05 level are discussed as marginally significant. After adjustment for age, education, and resting blood pressure, greater SBP reactivity was associated with poorer performance on Digits Forward (R2 = .110, p = .007) and greater DBP reactivity was associated with poorer performance on Digits Forward (R(2) = .124, p = .003) and the Boston Naming Test (R(2) = .118, p = .008); associations with DBP reactivity and Alpha Span (R(2) = .104; p = .019) and CVLT free recall short delay (R(2) = .066, p = .032) were marginally significant. Greater BP reactivity was associated with poorer performance on tests of attention, verbal memory, and confrontation naming. BP reactivity may be a biobehavioral risk factor for lowered levels of cognitive performance.

Can Hostility Interfere with the Health Benefits of Giving and Receiving Social Support? The Impact of Cynical Hostility on Cardiovascular Reactivity During Social Support Interactions Among Friends

Both social support and hostility have been reliably associated with important health outcomes including coronary heart disease (CHD). One potential pathway by which these variables may influence CHD is via their impact on cardiovascular reactivity (CVR). Although social support has been generally associated with beneficial effects on cardiovascular functioning, the cynicism and mistrust among hostile individuals may prevent them from benefiting from the support process during times of stress. The present study examined if level of hostility influenced CVR when discussing positive or negative personal experiences with a friend. To test this, healthy males and females and their same-sex friend were recruited (N = 216) and randomly assigned to discuss either a positive or negative (stressful) personal experience while cardiovascular measures were recorded. Results revealed the greatest systolic blood pressure and diastolic blood pressure reactivity among individuals high in hostility when discussing a negative experience. These results suggest that hostility may interfere with the benefits from support transactions during stress. Likewise, this association between hostility and reactivity was apparent for both support recipients and support providers, suggesting that hostility could undermine the health benefits of both aspects of support transactions.

Genetic influences on blood pressure response to the cold pressor test: results from the Heredity and Phenotype Intervention Heart Study

Blood pressure (BP) response to the cold pressor test (CPT) has been found to predict the development of hypertension and cardiovascular disease in prospective studies. The determinants of BP response to the CPT, including the role of genetic factors, however, are largely unknown. Additionally, to our knowledge, no study has examined the genetics of BP recovery from the CPT, including whether shared genetic factors influence both reactivity and recovery. As part of the Heredity and Phenotype Intervention Heart Study, we administered a 2.5 min hand CPT to 835 participants from 18 extended Amish families. We estimated the heritability of BP reactivity and recovery (measured by the incremental area under the curve) and the genetic correlations between baseline, reactivity, and recovery BP phenotypes. After adjusting for relevant covariates, including baseline BP, the heritability estimates for both systolic BP (SBP) and diastolic BP (DBP) reactivity and recovery differed significantly from zero (P < 0.01), with 12-25% of the total variation in BP response attributable to additive genetic effects. The genetic correlations between baseline DBP and response phenotypes were not significantly different from zero, whereas the genetic correlation between DBP reactivity and recovery (0.74) was significantly different from zero and 1 (P < 0.005). The genetic correlation between SBP reactivity and recovery was similar (0.81; P < 0.05). We conclude that, independent of baseline BP, BP response to CPT is heritable, and that both shared and unshared genetic factors influence BP reactivity and recovery, thus stressing the importance of identifying genetic variants that influence both traits.