Enhanced adrenocortical responses to stress in hypertension-prone men and women

Physiological reactivity to acute mental stress in essential hypertension-a systematic review

Objective

Exaggerated physiological reactions to acute mental stress (AMS) are associated with hypertension (development) and have been proposed to play an important role in mediating the cardiovascular disease risk with hypertension. A variety of studies compared physiological reactivity to AMS between essential hypertensive (HT) and normotensive (NT) individuals. However, a systematic review of studies across stress-reactive physiological systems including intermediate biological risk factors for cardiovascular diseases is lacking.

Methods

We conducted a systematic literature search (PubMed) for original articles and short reports, published in English language in peer-reviewed journals in November and December 2022. We targeted studies comparing the reactivity between essential HT and NT to AMS in terms of cognitive tasks, public speaking tasks, or the combination of both, in at least one of the predefined stress-reactive physiological systems.

Results

We included a total of 58 publications. The majority of studies investigated physiological reactivity to mental stressors of mild or moderate intensity. Whereas HT seem to exhibit increased reactivity in response to mild or moderate AMS only under certain conditions (i.e., in response to mild mental stressors with specific characteristics, in an early hyperkinetic stage of HT, or with respect to certain stress systems), increased physiological reactivity in HT as compared to NT to AMS of strong intensity was observed across all investigated stress-reactive physiological systems.

Conclusion

Overall, this systematic review supports the proposed and expected generalized physiological hyperreactivity to AMS with essential hypertension, in particular to strong mental stress. Moreover, we discuss potential underlying mechanisms and highlight open questions for future research of importance for the comprehensive understanding of the observed hyperreactivity to AMS in essential hypertension.

Hyperreactivity of Salivary Alpha-Amylase to Acute Psychosocial Stress and Norepinephrine Infusion in Essential Hypertension

It is unknown whether the observed general physiological hyperreactivity to acute psychosocial stress in essential hypertension also extends to salivary alpha-amylase (sAA), a surrogate sympathetic nervous system marker. Here, we investigated sAA reactivity to acute psychosocial stress in essential hypertensive males (HT) as compared to normotensive controls (NT). To shed light on underlying mechanisms, we moreover tested for sAA reactivity following a standardized norepinephrine (NE) infusion. We hypothesized that both acute psychosocial stress and an NE infusion of similar duration would lead to greater sAA reactivity in HT than in NT. In the stress study, we examined sAA reactivity to 15 min of acute psychosocial stress induced by the Trier Social Stress Test (TSST) in 19 HT and 23 NT up to 40 min after stress. In the infusion study, 20 HT and 22 NT received a standardized NE infusion (5 μg/mL/min) over 15 min mimicking NE release in reaction to acute psychosocial stress. HT exhibited greater sAA reactivity to the TSST as compared to NT (p = 0.049, η_p² = 0.08, f = 0.29). In reaction to the standardized NE infusion, HT showed higher sAA reactivity as compared to NT (p = 0.033, η_p² = 1.00, f = 0.33). Our findings suggest stress-induced sAA hyperreactivity in essential hypertension that seems to be at least in part mediated by a higher reactivity to a standardized amount of NE in HT. With respect to clinical implications, sAA stress reactivity may serve as a noninvasive marker indicative of early cardiovascular risk.

Alpha-Adrenergic Mechanisms in the Cardiovascular Hyperreactivity to Norepinephrine-Infusion in Essential Hypertension

AIMS

Essential hypertension (EHT) is characterized by cardiovascular hyperreactivity to stress but underlying mechanism are not fully understood. Here, we investigated the role of α-adrenergic receptors (α-AR) in the cardiovascular reactivity to a norepinephrine (NE)-stress reactivity-mimicking NE-infusion in essential hypertensive individuals (HT) as compared to normotensive individuals (NT).

METHODS

24 male HT and 24 male NT participated in three experimental trials on three separate days with a 1-min infusion followed by a 15-min infusion. Trials varied in infusion-substances: placebo saline (Sal)-infusions (trial-1:Sal+Sal), NE-infusion without (trial-2:Sal+NE) or with non-selective α-AR blockade by phentolamine (PHE) (trial-3:PHE+NE). NE-infusion dosage (5µg/ml/min) and duration were chosen to mimic duration and physiological effects of NE-release in reaction to established stress induction protocols. We repeatedly measured systolic (SBP) and diastolic blood pressure (DBP) as well as heart rate before, during, and after infusions.

RESULTS

SBP and DBP reactivity to the three infusion-trials differed between HT and NT (p's≤.014). HT exhibited greater BP reactivity to NE-infusion alone compared to NT (trial-2-vs-trial-1: p's≤.033). Group differences in DBP reactivity to NE disappeared with prior PHE blockade (trial-3: p=.26), while SBP reactivity differences remained (trial-3: p=.016). Heart rate reactivity to infusion-trials did not differ between HT and NT (p=.73).

CONCLUSION

Our findings suggest a mediating role of α-AR in DBP hyperreactivity to NE-infusion in EHT. However, in SBP hyperreactivity to NE-infusion in EHT, the functioning of α-AR seems impaired suggesting that the SBP hyperreactivity in hypertension is not mediated by α-AR.

Corroborative evidence for an association between initial hypothalamic-pituitary-adrenocortical axis reactivity and subsequent habituation in humans

BACKGROUND

The extant literature predicts that initial hypothalamic-pituitary-adrenocortical (HPA) axis response magnitude and subsequent habituation are associated with health, such that both heightened stress reactivity and non-habituation to repeated stressors are associated with disease. Yet, despite evidence for an association between initial HPA axis reactivity and subsequent habituation, the extant literature often considers health implications of these stress response patterns independently or make interpretations based on an initial response alone. This may be because past tests of the association between reactivity and habituation were subject to statistical bias (e.g., regression to the mean), and no prior work has examined the association between initial cortisol reactivity and subsequent habituation using analytic strategies capable of estimating the unbiased relationship between initial value (i.e., reactivity) and subsequent change (i.e., habituation). Accordingly, the present investigation drew from two previously published studies to test the association between initial HPA axis reactivity and subsequent habituation using analytic strategies capable of estimating the relationship between initial reactivity and subsequent habituation with minimal bias.

METHODS

We examined salivary cortisol and plasma ACTH responses to three repeated social-evaluative stressors (Study 1) and salivary cortisol responses to two repeated social-evaluative stressors (Study 2).

RESULTS

As predicted, results indicated a negative relationship (Pearson's r ranging from -0.27 to -0.91) where initial HPA axis reactivity was associated with subsequent habituation across both studies, even when using estimation procedures capable of producing an unbiased estimate of this relationship.

CONCLUSIONS

Results support the claim that initial HPA axis reactivity to acute stress is associated with subsequent habituation, such that initially high reactors are likely to habituate, whereas initially blunted reactors are likely to sensitize. In view of these results, hypothesized long-term health implications of acute cortisol reactivity and habituation patterns should be considered in tandem.

Stress and Health: A Review of Psychobiological Processes

The cumulative science linking stress to negative health outcomes is vast. Stress can affect health directly, through autonomic and neuroendocrine responses, but also indirectly, through changes in health behaviors. In this review, we present a brief overview of (a) why we should be interested in stress in the context of health; (b) the stress response and allostatic load; (c) some of the key biological mechanisms through which stress impacts health, such as by influencing hypothalamic-pituitary-adrenal axis regulation and cortisol dynamics, the autonomic nervous system, and gene expression; and (d) evidence of the clinical relevance of stress, exemplified through the risk of infectious diseases. The studies reviewed in this article confirm that stress has an impact on multiple biological systems. Future work ought to consider further the importance of early-life adversity and continue to explore how different biological systems interact in the context of stress and health processes.

Serum cortisol but not oxidative stress biomarkers are related to frailty: results of a cross-sectional study in Spanish older adults

Frailty is a multidimensional geriatric syndrome of loss of reserves and increased vulnerability to negative health outcomes. Cortisol, the major hormone of the hypothalamic pituitary adrenal (HPA) axis, and oxidative stress may be influenced by multiple endogenous and environmental factors throughout the lifespan, triggering changes in organism functioning. Association of elevated levels of cortisol and oxidative stress biomarkers with aging and several age-related diseases is well documented. However, the possible role of these factors on frailty status in older adults has not been extensively studied. Hence, the aim of this study was to conduct a cross-sectional study in 252 older adults (≥65 years old) classified according to their frailty status. Plasma cortisol and biomarkers related to oxidative stress including reactive oxygen/nitrogen species, oxidative DNA damage, and total antioxidant capacity were determined in non-frail, pre-frail, and frail subjects. Results showed significantly increasing cortisol concentrations with frailty burden, but no marked association between any oxidative stress biomarker and frailty status. In addition, dependence on activities of daily living and 10-year mortality risk were also correlated with elevated cortisol levels. Current results support the hypothesis that age-related HPA axis dysregulation is associated with frailty status, although further research is necessary to establish the role of cortisol in the pathophysiology of frailty.

Stress and Addiction: When a Robust Stress Response Indicates Resiliency

OBJECTIVE

Stress reactivity research has traditionally focused on the idea that exaggerated responses to stress may have adverse effects on health. Accumulating evidence suggests that attenuated responses to stress and delayed recovery may also be problematic.

METHODS

This review focuses on the role of the stress response of the hypothalamic-pituitary-adrenocortical axis, the endogenous opioid system, and the cardiovascular system in hypertension, pain perception, and addictive behaviors. Results from multiple methods of assessment and stress paradigms conducted in our laboratory over the past two decades are integrated with research from other investigators and with existing theories.

RESULTS

Research indicates that exaggerated biological and physiological responses to stress and attenuated pain perception are associated with hypertension and risk for cardiovascular diseases. This research complements work linking reduced stress responses with enhanced pain sensitivity and discomfort. Multiple studies have also demonstrated that an attenuated stress response is linked to exacerbation of withdrawal symptoms and relapse in nicotine addiction. Evidence indicates important moderators (i.e., sex, personality traits, and early life adversity) and hypothalamic-pituitary-adrenocortical- and endogenous opioid system-related mechanisms in the altered response to stress. I integrate these findings in a conceptual model emphasizing that robust stress responses in the context of addiction and relapse should be considered as a marker of resiliency.

CONCLUSIONS

A blunted stress response may indicate long-term physiological dysregulation that could usher harmful consequences for cardiovascular disease, pain perception, and addictive disorders. The impact of dysregulation is influenced by multiple individual and situational factors that should be considered in evaluating the clinical significance of stress response dysregulation.

Stress response dysregulation and stress-induced analgesia in nicotine dependent men and women

Alterations in the stress response and endogenous pain regulation mechanisms may contribute directly and indirectly to maintenance of nicotine dependence and relapse. We examined the extent to which nicotine dependence alters endogenous pain regulatory systems, including the hypothalamic-pituitary-adrenocortical axis, cardiovascular activity, and stress-induced analgesia. Smokers and nonsmokers attended a laboratory session that included assessment of hormonal and cardiovascular responses to stress. Smokers smoked at their regular rate prior to the session. The hand cold pressor and heat thermal pain tests were completed twice, once after acute stress (public speaking and math tasks) and the other after rest. While smokers and nonsmokers exhibited significant hormonal and cardiovascular responses to stress, smokers exhibited blunted stress responses relative to nonsmokers. They also exhibited diminished stress-induced analgesia. Results demonstrate altered stress response and diminished stress-induced analgesia among chronic smokers, and suggest that these dysregulated physiological responding may contribute to altered endogenous pain regulation.

Decreased Cognitive/CNS Function in Young Adults at Risk for Hypertension: Effects of Sleep Deprivation

Hypertension has been linked to impaired cognitive/CNS function, and some of these changes may precede development of frank essential hypertension. The stress and fatigue of sleep deprivation may exacerbate these cognitive changes in young adults at risk. We hypothesize that individuals at risk for hypertension will show significant declines in cognitive function during a night of sleep deprivation. Fifty-one young adults were recruited for 28-hour total sleep deprivation studies. Hypertension risk was assessed by mildly elevated resting blood pressure and by family history of hypertension. A series of cognitive memory tasks was given at four test sessions across the sleep deprivation period. Although initially comparable in cognitive performance, persons at risk showed larger declines across the night for several indices of working memory, including code substitution, category, and order recall. These results suggest that cognitive/CNS changes may parallel or precede blood pressure dysregulation in the early stages of hypertension development. The role of CNS changes in the etiology of essential hypertension is discussed.

Biofeedback-assisted cardiovascular control in hypertensives exposed to emotional stress: a pilot study

The study was aimed at examining the effect of a short Heart Rate-Biofeedback (HR-BF) protocol on systolic (SBP) and diastolic (DBP) blood pressure levels and BP emotional reactivity. Twenty-four unmedicated outpatients with pre- and stage 1 hypertension, were randomly assigned to active treatment (BF-Training) or control (BP-Monitoring) group. Subjects in BF-Training Group underwent four BF sessions. Guided imagery of stressful events was introduced during sessions 3 and 4. Control participants self-monitored their BP at home for 4 weeks. Subjects in both groups performed an emotional Speech Test before and after the training (or monitoring) period. SBP and mean arterial pressure responses to the emotional Speech Test were significantly smaller after the BF-training than the BP-monitoring. Moreover, clinic SBP and DBP were significantly reduced by about 10 mmHg in BF-Training Group, whereas they remained unchanged in control group. Self-monitored BP decreased significantly in the active treatment group and not in control group. A short BF-training, including guided imagery of stressful events, was effective in reducing BP reactions to a psychosocial stressor. BP measured in the clinic, and self-monitored at home were also significantly reduced in the BF-Training Group. HR-BF appears to be a suitable intervention for hypertensive patients, mostly when BP increase is associated with emotional activation.

Long-term effect of yogic practices on diurnal metabolic rates of healthy subjects

Background:

The metabolic rate is an indicator of autonomic activity. Reduced sympathetic arousal probably resulting in hypometabolic states has been reported in several yogic studies.

Aim:

The main objective of this study was to assess the effect of yoga training on diurnal metabolic rates in yoga practitioners at two different times of the day (at 6 a.m. and 9 p.m.).

Materials and Methods:

Eighty eight healthy volunteers were selected and their metabolic rates assessed at 6 a.m. and 9 p.m. using an indirect calorimeter at a yoga school in Bangalore, India. Results and conclusions: The results show that the average metabolic rate of the yoga group was 12% lower than that of the non-yoga group (P < 0.001) measured at 9 p.m. and 16% lower at 6 a.m. (P < 0.001). The 9 p.m. metabolic rates of the yoga group were almost equal to their predicted basal metabolic rates (BMRs) whereas the metabolic rate was significantly higher than the predicted BMR for the non-yoga group. The 6 a.m. metabolic rate was comparable to their predicted BMR in the non-yoga group whereas it was much lower in the yoga group (P < 0.001). The lower metabolic rates in the yoga group at 6 a.m. and 9 p.m. may be due to coping strategies for day-to-day stress, decreased sympathetic nervous system activity and probably, a stable autonomic nervous system response (to different stressors) achieved due to training in yoga.

Cardiovascular, hormonal, and emotional responses to the TSST in relation to sex and menstrual cycle phase

The prevalence of stress disorders differs between men and women. An understanding of how men and women vary in acute stress responses may help to understand these sex differences. We compared responses to the TSST and a control task in healthy men (N=28) and women tested in two phases (Follicular N=29, Luteal N=23) of the menstrual cycle. Men exhibited greater cortisol responses to stress than women in either phase. Luteal women exhibited the greatest subjective and allopregnanolone responses to stress, whereas follicular women exhibited blunted noradrenaline responses. Partial correlations controlling for group differences revealed that individuals who were most sensitive to the subjective effects of stress exhibited the largest salivary cortisol, noradrenaline, and allopregnanolone responses and the smallest progesterone responses to stress. We discuss our findings in the context of sex differences in the prevalence of stress-linked disorders.

Salivary alpha-amylase as a non-invasive biomarker for the sympathetic nervous system: current state of research

Development of new biomarkers is a constantly evolving field of research endeavor in psychoneuroendocrinology. Salivary biomarkers have received special attention since they are readily accessible and easily obtained. Salivary alpha-amylase (sAA) has been proposed as a sensitive biomarker for stress-related changes in the body that reflect the activity of the sympathetic nervous system (SNS), and a growing body of research is accumulating to support the validity and reliability of this parameter. However, questions remain to be answered before sAA can be accepted as an index of SNS activity. This review describes sAA as an emerging biomarker for stress and provides an overview of the current literature on stress-related alterations in sAA. It critically discusses how sAA might reflect changes in the autonomic nervous system. Finally, current and future fields for the application of sAA measurement are outlined.

Corticotropin-releasing hormone neurons in hypertensive patients are activated in the hypothalamus but not in the brainstem

The corticotrophin-releasing hormone (CRH)-expressing neurons were studied in the hypothalamus and brainstem of individuals who suffered from essential hypertension and had died due to acute myocardial infarction or brain hemorrhage. Healthy normotensive individuals who died in accidents made up the control group. In hypertensive patients we found extremely high expression of CRH in all parts of the hypothalamic paraventricular nucleus (Pa). In addition, CRH neuronal profiles were observed in the caudal hypothalamic area and dorsal parts of the extended amygdala. In the control group, CRH neurons were found only in the Pa and in much smaller numbers than in hypertensive patients. Also, in contrast to the controls, we found in hypertensives a very high number of CRH fibers running from the most rostral part of the Pa to the median eminence and innervating the caudal part of the suprachiasmatic nucleus (SCh). A quantitative evaluation showed that the area covered by CRH fibers in the SCh of hypertensives was about three times larger than that in the control SCh. Linear regression analysis demonstrated a negative correlation between the area of CRH fibers and the number of vasopressin (VP) or neurotensin (NT) neurons within the SCh. This relationship occurred particularly in hypertensive patients in whose SCh a larger CRH fiber area and a smaller number of VP or NT neurons were observed. We found a few CRH neuronal profiles and fibers in brainstem nuclei that are involved in cardiovascular regulation, but no apparent difference was observed between the control and hypertensive group.

Hypothalamic blood flow correlates positively with stress-induced cortisol levels in subjects with social anxiety disorder

OBJECTIVE

The adrenal excretion of cortisol in animals is dependent on the production of corticotropin-releasing factor in the paraventricular nucleus of the hypothalamus. The a priori hypothesis of this study was that hypothalamic regional cerebral blood flow (rCBF) would correlate positively with salivary cortisol levels in patients with social anxiety disorder (SAD) during anxiety provocation. Another objective was to evaluate whether salivary cortisol levels correlated with rCBF in other brain areas.

METHOD

Regional CBF was measured with oxygen-15-labeled water and positron emission tomography during a public speaking task before and after placebo treatment in 12 subjects with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-defined SAD. Cortisol concentrations in saliva were measured 15 minutes after the task. The a priori hypothesis of a salivary cortisol-dependent activation of the hypothalamus was studied with region-of-interest analysis. In addition, the covariation between rCBF and salivary cortisol was studied in the whole brain using the general linear model.

RESULTS

The region-of-interest analysis revealed a positive correlation between salivary cortisol and hypothalamic rCBF. In the whole brain analysis, a positive covariation between rCBF and salivary cortisol levels was found in a midbrain cluster encompassing the hypothalamus with its statistical maximum in the mamillary bodies. Negative covariations were observed in the medial prefrontal cortex as well as in the motor and premotor cortices.

CONCLUSION

Like in animals, stress-induced cortisol excretion in humans may be inhibited by activity in the medial prefrontal cortex and enhanced by activity in the hypothalamus.

Low social support and poor emotional regulation are associated with increased stress hormone reactivity to mental stress in systemic hypertension

CONTEXT

There is strong evidence for a physiological hyperreactivity to stress in systemic hypertension, but data on associated or potentially moderating psychological factors are scarce.

OBJECTIVE

The objective of the study was to identify psychological correlates of physiological stress reactivity in systemic hypertension.

DESIGN

This was a cross-sectional, quasi-experimentally controlled study. Study participants underwent an acute standardized psychosocial stress task combining public speaking and mental arithmetic in front of an audience.

SETTING

The study was conducted in the population in the state of Zurich, Switzerland.

SUBJECTS

Subjects included 22 hypertensive and 26 normotensive men (mean +/- sem 44 +/- 2 yr).

MAIN OUTCOME MEASURES

We assessed the psychological measures social support, emotional regulation, and cognitive appraisal of the stressful situation. Moreover, we measured salivary cortisol and plasma epinephrine and norepinephrine before and after stress and several times up to 60 min thereafter as well as blood pressure and heart rate.

RESULTS

We found poorer hedonistic emotional regulation (HER) and lower perceived social support in hypertensives, compared with normotensives (P < 0.01). Compared with normotensives, hypertensives showed higher cortisol, epinephrine, and norepinephrine secretions after stress (P < 0.038) as well as higher systolic and diastolic blood pressure (P < 0.001). Cortisol reactivity and norepinephrine secretion were highest in hypertensive men with low HER (P < 0.05). In contrast, hypertensives with high HER did not significantly differ from normotensives in both cortisol and norepinephrine secretion after stress. Epinephrine secretion was highest in hypertensives with low social support but was not different between hypertensives with high social support and normotensives.

CONCLUSIONS

The findings suggest that both low social support and low HER are associated with elevated stress hormone reactivity in systemic hypertension.

The effect of long term combined yoga practice on the basal metabolic rate of healthy adults

Background

Different procedures practiced in yoga have stimulatory or inhibitory effects on the basal metabolic rate when studied acutely. In daily life however, these procedures are usually practiced in combination. The purpose of the present study was to investigate the net change in the basal metabolic rate (BMR) of individuals actively engaging in a combination of yoga practices (asana or yogic postures, meditation and pranayama or breathing exercises) for a minimum period of six months, at a residential yoga education and research center at Bangalore.

Methods

The measured BMR of individuals practicing yoga through a combination of practices was compared with that of control subjects who did not practice yoga but led similar lifestyles.

Results

The BMR of the yoga practitioners was significantly lower than that of the non-yoga group, and was lower by about 13 % when adjusted for body weight (P < 0.001). This difference persisted when the groups were stratified by gender; however, the difference in BMR adjusted for body weight was greater in women than men (about 8 and 18% respectively). In addition, the mean BMR of the yoga group was significantly lower than their predicted values, while the mean BMR of non-yoga group was comparable with their predicted values derived from 1985 WHO/FAO/UNU predictive equations.

Conclusion

This study shows that there is a significantly reduced BMR, probably linked to reduced arousal, with the long term practice of yoga using a combination of stimulatory and inhibitory yogic practices.

Perceived racism and vascular reactivity in black college women: moderating effects of seeking social support

This quasi-experimental study explored the association of perceived racism and seeking social support to vascular reactivity in a college sample of 110 Black women. Perceived racism and seeking social support were assessed via self-report, and vascular reactivity was measured before and during a standardized speaking task. Hierarchical regression analyses indicated that perceived racism was positively related to changes in systolic blood pressure. These analyses also indicated that seeking social support moderated the relationship between perceived racism and systolic blood pressure changes. This interaction effect persisted after controlling for several potential confounders. Follow-up regression analyses showed that perceived racism was positively associated with reactivity among participants who were low in seeking social support. A significant relationship was not observed between perceived racism and systolic blood pressure changes among participants who were high in seeking social support. Perceived racism and seeking social support were not significantly associated with changes in diastolic blood pressure. These findings highlight the importance of examining psychosocial factors that may mitigate the hypothesized relationship between perceived racism and reactivity.

Stress management for African American women with elevated blood pressure: a pilot study

This article reports the results of a pilot study testing the effects of two stress management interventions on blood pressure (BP) and stress-related variables in employed African American women. Thirty-three women with mean age 44.8 +/- 7.6 years were randomly assigned to a cognitive mediation group (n=10), a relaxation group (n=12), or a delayed treatment control group (n=11). The participants in the two stress management groups participated in a 10-week intervention; the delayed treatment control group received BP monitoring during the 10-week period. Measures included BP, the State-Trait Anger Expression Inventory, Personal Strain, and Coping Resources. Although no significant Group x Time effects were found in BP, anger, or personal strain, several of the outcome measures appear to be sensitive and showed cell means in the hypothesized direction. Further study of the effects of stress management interventions on BP and stress, with a larger sample, is warranted.

Adrenocortical and nociceptive responses to opioid blockade in hypertension-prone men and women

OBJECTIVE

Attenuated pain sensitivity and exaggerated adrenocortical stress reactivity have been documented in individuals at high risk for hypertension. The endogenous opioid system may play a role in these response alterations. We compared adrenocortical and nociceptive responses to opioid blockade using naltrexone in hypertension-prone men and women.

METHODS

Ninety-nine participants completed two sessions during which a placebo or 50 mg naltrexone was administered using a double-blind, counterbalanced design. Participants rated their pain and completed the McGill Pain Questionnaire (MPQ) after three assessments of the nociceptive flexion reflex and after assessment of nociceptive pain threshold and tolerance. Saliva samples were obtained throughout the sessions.

RESULTS

Salivary cortisol levels increased after pain assessment after the ingestion of naltrexone, but not after placebo, with the low-risk group exhibiting an earlier peak of cortisol response. Participants reported greater pain ratings and higher MPQ scores in the naltrexone versus placebo condition, and these effects were more pronounced in women. Pain threshold and tolerance were higher among high-risk men relative to low-risk men.

CONCLUSIONS

The results are consistent with the inhibitory effects of the endogenous opioids on cortisol response and suggest an altered response timeline among hypertension-prone individuals. The results demonstrate that hypoalgesia may be a marker of hypertension risk in men but not in women.

A meta-analysis of cortisol response to challenge in human aging: importance of gender

An increased cortisol response to challenge is associated with a variety of age-related disorders such as Alzheimer's disease, depression, diabetes, metabolic syndrome, and hypertension. Among the healthy elderly, an increased cortisol response to challenge may be a risk factor for developing these age-related disorders. We searched Pubmed, Embase, PsychInfo, Biosis, and Digital Dissertations (January 1966-June 2003) and included 45 parallel-group (young vs. old subjects) studies that used either a pharmacological or psychological challenge in healthy volunteers and measured cortisol response to challenge. We calculated effect sizes (Cohen's d) for the standardized mean differences between groups. Compared to younger controls (n=670, mean age 28 years +/-5), older subjects (n=625, 69+/-6) showed a larger cortisol response to challenge defined as stronger response to stimulation or less inhibition after a suppression test (d=0.42, 95% confidence interval (CI), 0.26-0.57). The effect of age on cortisol release was significantly stronger in women (d=0.65, 95% CI 0.34-0.97) than men (d=0.24, 95% CI 0.02-0.47). Our results demonstrate that aging increases the cortisol response to challenge. This effect of age on cortisol response is almost three-fold stronger in women than men. Prospective studies should explore whether the higher cortisol response in the elderly is a risk factor for developing neuropsychiatric and medical disorders.

DS14: standard assessment of negative affectivity, social inhibition, and Type D personality

OBJECTIVE

Type D personality-a joint tendency toward negative affectivity (NA) and social inhibition (SI)-is related to poor cardiac prognosis, but there is no standard for assessing Type D. This study reports on the Type D Scale-14 (DS14) as a standard measure of NA, SI, and Type D.

METHODS

The study included 3813 participants (2508 from the general population, 573 cardiac patients, 732 hypertension patients). They all filled out the DS14, containing 7-item NA and SI subscales; 275 subjects also completed the NEO-FFI, and 121 patients filled out the DS14 twice.

RESULTS

Factor analysis of the DS14 yielded 2 dominant traits; all of the NA and SI items loaded between 0.62 to 0.82 on their corresponding factor (N = 3678). The NA scale covered dysphoria, worry, and irritability; the SI scale covered discomfort in social interactions, reticence, and lack of social poise. The NA and SI scales were internally consistent (alpha = 0.88/0.86; N = 3678), stable over a 3-month period (test-retest r = 0.72/0.82) and not dependent on mood and health status (N = 121). NA correlated positively with neuroticism (r = 0.68); SI correlated negatively with extraversion (r = -0.59/-0.65). Scale-level factor analysis confirmed the construct validity of the DS14 against the NEO-FFI. Using a cutoff of 10 (NA > or =10 and SI > or =10), 1027 subjects (28%) were classified as Type D, 21% in the general population versus 28% in coronary heart disease and 53% in hypertension (p < or = .001). Age, sex, and Type D (odds ratio, 3.98; 95% confidence interval, 3.2-4.6; p <.0001) were independently associated with cardiovascular morbidity.

CONCLUSION

The DS14 is a brief, psychometrically sound measure of negative affectivity and social inhibition that could readily be incorporated in epidemiologic and clinical research.

Interactions between the cardiovascular and pain regulatory systems: an updated review of mechanisms and possible alterations in chronic pain

Endogenous pain regulatory system dysfunction appears to play a role in the maintenance of chronic pain. An important component of the pain regulatory process is the functional interaction between the cardiovascular and pain regulatory systems, which results in an association between elevated resting blood pressure (BP) and diminished acute pain sensitivity. This BP/pain sensitivity relationship is proposed to reflect a homeostatic feedback loop helping restore arousal levels in the presence of painful stimuli. Evidence is emerging that this normally adaptive BP/pain sensitivity relationship is significantly altered in chronic pain conditions, affecting responsiveness to both acute and chronic pain stimuli. Several mechanisms that may underlie this adaptive relationship in healthy individuals are overviewed, including endogenous opioid, noradrenergic, and baroreceptor-related mechanisms. Theoretical models are presented regarding how chronic pain-related alterations in the mechanisms above and increased pain facilatory system activity (central sensitization) may contribute to altered BP/pain sensitivity interactions in chronic pain. Clinical implications are discussed.

Sex differences in pain and hypothalamic-pituitary-adrenocortical responses to opioid blockade

OBJECTIVE

Sex differences in pain sensitivity and stress reactivity have been well documented. Little is known about the role of the endogenous opioid system in these differences. This study was conducted to compare adrenocortical, pain sensitivity, and blood pressure responses to opioid blockade using naltrexone in men and women.

METHODS

Twenty-six participants completed 2 sessions during which placebo or 50 mg of naltrexone was administered, using a double-blind, counterbalanced design. Thermal pain threshold and heat tolerance were assessed. Participants also rated pain during a 90-second cold pressor test (CPT) and completed the McGill Pain Questionnaire (MPQ) after each pain challenge. Blood and saliva samples and cardiovascular and mood measures were obtained throughout the sessions.

RESULTS

Plasma cortisol, adrenocorticotropin, beta endorphin, prolactin, and salivary cortisol levels increased similarly in men and women after naltrexone administration compared with placebo. Women reported more pain during both pain procedures and had lower thermal pain tolerance. In response to naltrexone, women exhibited reduced blood pressure responses and reduced MPQ pain ratings after CPT. No effects of naltrexone on these measures were found in men.

CONCLUSIONS

Although men and women exhibited similar hormonal responses to opioid receptor blockade, women reported less pain and showed smaller blood pressure responses during CPT. Results suggest differential effects of the endogenous opioid system on pain perception and blood pressure in men and women.

Pregnancy as a stressful life event and strategies for coping with stress in women with pregnancy-induced hypertension

Introduction Pregnancy-induced hypertension (PIH) represents an extremely important problem in perinatology. Despite numerous clinical observations and studies, the etiology and exact sequence of pathophysiological events accompanying this specific disorder have remained still unresolved. The concepts most often considered are those that include genetic, endocrine and immunological mechanisms. Besides, one can also find in the literature considerations addressing potential participation of psychological factors in pregnancy-induced hypertension. Material and methods The study included two groups of women - 100 women with PIH and 100 of women with normal course of pregnancy, which were tested using two questionnaires concerning pregnancy as a stressful event and using strategies for coping with stress. Results and discussion Women with PIH experience pregnancy in a more stressful way than women with regular course of pregnancy. However, it is necessary to point out that respondents of both groups thought that pregnant women seek attention from everyone from their environment, and that their husbands/partners should pay special attention to them during pregnancy. The importance of relationship between partners during pregnancy and the emotional life of pregnant woman has been also examined by other researchers. These data suggest that pregnancy is an emotionally vulnerable period during which women demand special attention from the environment and especially from their husbands/partners. In view of using particular strategies to cope with stress, certain differences have been registered between the two groups of women. Namely, women with PIH utilize much more the mechanism of seeking social support and much less the mechanism of positive redefinition, compared with women with normal course of pregnancy. Conclusion From the psychosocial approach, pregnancy may be considered as a specific state of high emotional tension, which can represent a potent stressor. In the frame of specific reactions to stress, pregnancy as a stress-inducing situation may lead to transformation of emotional tension to biochemical and vegetative response, and thus contribute to onset of pregnancy-induced hypertension.