The short-term effect of water-pipe smoking on the baroreflex control of heart rate in normotensives.

UNLABELLED: The aim of this study is to analyse the acute effect of water-pipe smoking on heart rate, blood pressure and the baroreflex control of heart rate. SUBJECTS AND METHODS: Non-invasive continuous methods were used for investigating inter-beat interval (IBI; ms), systolic blood pressure (SBP; mm Hg), diastolic blood pressure (DBP; mm Hg), pulse pressure (PP; mm Hg), mean blood pressure (MBP; mm Hg); baroreflex sensitivity in ms/mm Hg (BRS) and baroreflex sensitivity in Hz/mm Hg (BRSf), were determined by spectral analysis, in 20 normotensive volunteers age of 27+/-6 years (mean+/-S.D.) who served as their own control. The measurements were taken twice. The first measurement was taken before the water-pipe smoking session (this is after >12 h of smoking cessation with a complete stopping of alcohol, coffee or tea consumption). The second measurement was taken during a 5 min period immediately after that session. (In the smoking session the volunteer smokes 5 g Maassel (fruit flavoured tobacco) for a period of 45 min). RESULTS: The inter-beat interval decreased (846+/-100 to 709+/-109 ms, p=0.0003), SBP increased (110+/-13 to 123+/-12 mm Hg, p=0.004), DBP increased (67+/-11 to 81+/-11 mm Hg, p=0.0002), PP decreased (43+/-10 to 41+/-9 mm Hg, p=0.46 ns), MBP increased (82+/-10 to 95+/-11 mm Hg, p=0.0001), BRS decreased (9.16+/-4 to 5.67+/-3 ms/mm Hg, p=0.003) and BRSf (0.013+/-0.005 to 0.011+/-0.004 Hz/mm Hg, p=0.3 ns). CONCLUSIONS: Water-pipe smoking induced a high increase in heart rate, SBP, DBP, MBP and markedly impaired BRS. All of those markers are known as risk factors in cardiovascular diseases, hence it is concluded that water-pipe smoking is not as harmless as is thought.

Multimodal assessment of the effect of chewing gum on nicotine withdrawal.

The present study was designed to evaluate the usefulness of chewing gum to reduce nicotine withdrawal, craving, and salivary cortisol concentrations during temporary nicotine deprivation. A total of 20 male smokers were studied under conditions when gum was and was not accessible during a 4-hour deprivation period. All subjects smoked an initial cigarette shortly after arrival for the two experimental sessions and were informed that they would be unable to smoke for the remainder of each session. The sessions consisted of each subject watching a movie, then waiting in the lab for two consecutive 30-min intervals. Self-reported nicotine withdrawal and craving were assessed four times and salivary cortisol five times during each experimental session. Results from this study indicate that chewing gum helps with self-reported withdrawal but not craving when a smoker is prevented from smoking. This study also provides preliminary data on the use of salivary cortisol as a physiological marker that may map these self-reports of nicotine withdrawal and craving.

Adrenocortical responses to psychological stress and risk for hypertension.

Excessive and prolonged stress-induced cortisol changes may contribute to or be a marker of essential hypertension. Cortisol is a central component of the stress response, and it interacts with sympathetic and renal mechanisms contributing to increased blood pressure (BP). Although research in individuals with already established hypertension failed to show consistent abnormalities in adrenocortical output, cortisol responses to psychological stress are greater and more persistent in persons at high risk for hypertension relative to low-risk normotensives. Considering the heterogeneous and multifactorial polygenic nature of hypertension and the fact that cortisol affects several BP related processes, and regulates expression of genes involved in BP, it is possible that this hormone is involved in at least a sub-type of hypertension. Recent studies evaluating cortisol tissue sensitivity, cortisol production and cortisol metabolic rate in hypertension-prone persons support the possibility that cortisol may serve as an intermediate phenotype of hypertension. In this review, we discuss components of the stress responses, factors influencing the adrenocortical response, adrenocortical activity in hypertension, and we propose pathways that mediate effects of stress-induced cortisol on BP.

Adrenocorticotropin responses to interpersonal stress: effects of overt anger expression style and defensiveness.

This study evaluated the influence of overt anger expression style and defensiveness on the hypothalamic-pituitary-adrenocortical (HPA) responses to acute psychological stress. These personality traits are thought to modulate the stress cardiovascular response and influence disease risk, however, little is known about their influence on HPA responses. Forty-six young, healthy male volunteers worked on counterbalanced extended public-speaking and mental arithmetic. The sample was dichotomitized into groups low vs. high in anger-out, using Spielberger's Anger-Expression Inventory, and in defensiveness, using the Marlowe-Crown Social Desirability Scale. Serum cortisol and adrenocorticotropic hormone (ACTH) concentrations were measured before and after performing each task. Heart rate (HR) and blood pressures (BP) were obtained continuously in 2-min intervals before, during and after the tasks. Public speaking produced greater adrenocortical and cardiovascular stress responses than mental arithmetic, and the greatest increases in ACTH occurred in subjects high in anger-out and defensiveness. These preliminary findings provide evidence that a mismatch between traits of preferred anger expression style and defensive style produces pronounced adrenocorticotropic responses during socially salient stress.

Additive pressor effects of caffeine and stress in male medical students at risk for hypertension.

The effects of caffeine on blood pressure (BP) and cortisol secretion were examined during elevated work stress in medical students at high versus low risk for hypertension. Among 31 male medical students who were regular consumers of caffeine, 20 were considered at low risk for hypertension (negative parental history and all screening BP < 125/78 mm Hg) and 11 at high risk based on epidemiologic criteria (positive parental history and average screening BPs between 125/78 and 139/89 mm Hg). Cortisol levels and ambulatory BP were measured with and without caffeine during two lectures (low work stress) and two exams (high work stress) in a randomized, double-blind, crossover trial. Caffeine consumption and exam stress increased cortisol secretion in both groups (P < .05). BP increased with caffeine or exam stress in both groups, low versus high risk, respectively (Caffeine: + 5/4 vs + 3/3 mm Hg; Stress: + 4/1 vs + 7/3 mm Hg; P < .05). The combination of stress and caffeine caused additive increases in BP (Low Risk + 9/5 mm Hg, High Risk + 10/6 mm Hg) such that 46% of high-risk participants had average systolic BP > or = 140 mm Hg. This combined effect of stress and caffeine on BP suggests that it may be beneficial for individuals at high risk for hypertension to refrain from the use of caffeinated beverages, particularly at times when work demands and attendant stressors are high. For the same reasons, recent intake of caffeine should be controlled in patients undergoing BP measurement for the diagnosis of hypertension.

Sex differences in pain perception and cardiovascular responses in persons with parental history for hypertension.

We investigated gender differences in cardiovascular and pain responses to the cold pressor (CP) test in persons with positive (PH+) or negative parental history (PH-) for hypertension. Previous work has suggested an attenuated sensitivity to painful stimulation in hypertensive men and more recently in men with parental disposition for hypertension. It is not known whether this hypoalgesic effect is present in PH+ women. In this study, we evaluated differences in pain perception between men and women with PH+ or PH- using an assessment method to measure current as well as delayed pain. Participants rated their pain every 15 s during a 90-s hand CP (0-4 degrees C) and a 90-s post-CP rest period. Systolic and diastolic blood pressures (SBP, DBP) and heart rate (HR) were measured before, during, and after the CP. PH+ and PH- groups did not differ in age, height, weight, education, resting SBP, DBP, or HR. PH+ men showed greater DBP responses to the CP than PH- men, while female groups did not differ in cardiovascular responses to the CP. Although pain ratings during the CP did not differ between groups, post-CP reported pain receded faster in the PH+ men than in the PH- men. PH+ women, on the other hand, tended to report greater pain than PH- women. These findings question the generalizability of the hypoalgesic effects in hypertension-prone women.

Ultrasonographic urinary tract abnormalities in Schistosoma haematobium infection.

OBJECTIVE: Evaluation of ultrasonographic abnormalities with active Schistosoma haematobium infection in Yemeni patients. METHODS: As part of a cooperation between a private hospital and Schistosomiasis Control Project in Yemen, laboratory and ultrasonographic examinations were performed in 158 patients (8 females, 150 males, mean age: 17 years) with active Schistosoma haematobium infection. Upper urinary tract dilation, lower ureter changes and bladder wall abnormalities (thickness, hyperechogenicity and polypoid lesions) were registered. Laboratory findings and ultrasonographic changes were evaluated and assorted according to age groups of the patients. RESULTS: Twenty-eight patients (18%) showed no ultrasonographic morphological lesion. Bladder abnormalities (thickness, hyperechogenicity and polypoid lesions) were found in 130 patients (82%) and upper tract lesions in 86 patients (54%). No upper tract lesions were seen without bladder abnormality. Polyps within the lower ureteric lumen occurred in four patients. In patients with polypoid lesions, higher incidence of severe infection was found. One patient had urinary bladder mass. CONCLUSION: Urinary schistosomiasis has typical sonographic features, however, it may occur also without ultrasonographic morphological lesion. Upper tract lesions seem to develop only with lower tract abnormalities.

Cortisol fluctuates with increases and decreases in negative affect.

Prior studies have reported cortisol secretion to be primarily influenced by negative affect, but less is known about cortisol activity during states of activation involving increased positive affect and decreased negative affect. On separate days, 30 healthy young men experienced: an activating and humorous video; a speech stressor; and a resting control period. Cortisol was measured in saliva before and after each 30-min mood induction. Positive affect (activation) was increased similarly by both the video and the speech compared to rest (p < .0001). Negative affect increased during the speech and decreased during the video (p < .001). Cortisol increased only during the speech (p < .0001). Following the video, however, cortisol was decreased significantly (p < .0001). Rest day cortisol revealed no differences across periods (p > .1). These results suggest that the hypothalamic-pituitary-adrenocortical axis is a dynamic system influenced by changes in negative affect irrespective of the experience of generalized activation.

Hypothalamic-pituitary-adrenocortical responses to psychological stress and caffeine in men at high and low risk for hypertension.

OBJECTIVE: This study examined pituitary-adrenocortical responses to dietary doses of caffeine (3.3 mg/kg, equivalent to 2 to 3 cups of coffee), alone and combined with behavioral stress, in men at high risk versus low risk for hypertension. A randomized, double-blind, caffeine-placebo crossover design was used. METHOD: Adrenocorticotropic hormone (ACTH) and cortisol levels in plasma were assessed at rest and in response to 60-minutes of continuous work on a mental stressor (arithmetic) and a psychomotor task (reaction time) on four test sessions held on separate days. RESULTS: Tasks alone caused greater ACTH and cortisol increases in high risk men than in the low risk group. Caffeine alone elevated ACTH and cortisol in both groups, with more immediate responses in the high risk group. Both groups showed significant ACTH and cortisol responses to caffeine plus tasks, with the high risk group showing more persistent elevations. The high risk group also showed the highest levels of ACTH and cortisol after caffeine plus tasks. CONCLUSIONS: These findings demonstrate for the first time the combined effects of caffeine plus stress on ACTH and demonstrate greater corticosteroid effects in hypertension-prone men. As such, they may have implications for the dietary use of caffeine during periods of stress and in those at risk for hypertension.

Interactive effects of trait hostility and anger expression on cardiovascular reactivity in young men.

Hostility and anger-expression style are personality traits often associated with elevated cardiovascular reactivity and potential heightened risk for cardiovascular disease. In the present study a sample of 50 young, healthy men were divided into groups low or high on the Cook-Medley Hostility scale and on anger-out from Spielberger's Anger Expression scale. Subjects worked on mental arithmetic and public speaking tasks in counterbalanced order. Heart rate, systolic and diastolic blood pressure and hemodynamic indices were measured at baseline and during the tasks. Hostility and anger-out interacted in their effects on cardiovascular responses. The High Anger-Out/Low-Hostile group displayed the greatest increases in heart rate and blood pressures, while the High Anger-Out/High-Hostile group was least reactive. Furthermore, the High Anger-Out/Low-Hostile group showed a distinct fight/flight response pattern during public speaking, indicated by increases in stroke volume and cardiac output and a decrease in systemic vascular resistance. These results suggest that a mismatch between hostile cognitions and habitual anger expression leads to greater cardiovascular reactivity to challenging tasks, potentially enhancing risk for development of cardiovascular diseases.

Hemodynamics during rest and behavioral stress in normotensive men at high risk for hypertension.

Persons at risk for hypertension may show elevated blood pressure (BP) at rest and during mental stress; however, the hemodynamics underlying the BP of those persons at high risk are not well characterized. We chose 21 high risk and 21 low risk men using their parental hypertension history and resting systolic blood pressures on two screenings. Then, on a day of extended rest versus a day with prolonged mental arithmetic and reaction time tasks, we examined whether high risk BP elevations reflected greater vascular resistance or cardiac output. High risk men had raised systolic/diastolic pressures (Fs = 74/15, ps < .0001/.0001) and higher vascular resistance (F = 6.6, p < .02) with minimal differences in heart rate and cardiac output. This finding implicates vascular resistance as the altered element in BP control in these high risk men tested in a familiar environment with minimal task-related threat.

Cardiovascular responses during effortful active coping and acute experience of anger in women.

This study addresses the question of whether effortful active coping and anger provocation add in their effects on cardiovascular responses. Heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) responses of 64 female students were collected during an active versus nonactive coping task with and without provocation. After a baseline period, women did mental arithmetic (active coping) or read numbers aloud (nonactive coping). Half of each group was then additionally provoked. Ratings of the emotional states (Positive and Negative Affect Scale) indicate that provocation led to an increase in anger, but not in fear or negative or positive affect. Effortful active coping and provocation elevated cardiovascular activity. Although active coping enhanced all cardiovascular variables, provocation particularly affected HR and DBP. The effects of active coping and provocation on HR and DBP but not on SBP were additive and probably were produced by different physiological mechanisms.

Cardiovascular and neuroendocrine adjustment to public speaking and mental arithmetic stressors.

In this study, we evaluated cardiovascular, neuroendocrine, and psychological adjustment to repeated presentations of a public speaking and a mental arithmetic task. Brief versions of mental arithmetic tasks have been used widely in previous reactivity studies, and growing attention to more socially salient tasks has led to the increased use of public speaking tasks. However, psychophysiological adjustment during extended and repeated exposure to these tasks has not been delineated. In the present study, 52 healthy men worked on three 8-min presentations of public speaking and of mental arithmetic in a repeated measure design. Both tasks produced substantial cardiovascular, adrenocorticotropic hormone, and cortisol responses; public speaking produced greater changes. Repeated presentations of public speaking produced a stable pattern of cardiac activation, whereas repetitions of the mental arithmetic initially produced large cardiac responses that changed to a more vascular tonus across task periods. Both tasks increased negative moods. However, correlations between the endocrine, cardiovascular, and negative moods were significant only during the public speaking stressor. The public speaking task is a socially relevant experimental protocol for studying reactivity in the laboratory setting and elicits relatively high, stable, and homogeneous responses.

Men at risk for hypertension show elevated vascular resistance at rest and during mental stress.

Men at risk for development of hypertension may show elevated blood pressure at rest and during work on mental stressors. We examined which component of blood pressure, vascular resistance or cardiac output, accounted for raised blood pressures seen in a high-risk, normotensive sample. Parental history of hypertension and resting systolic blood pressures were used to categorize subjects into high (n = 19) and low (n = 14) risk groups. Blood pressure, heart rate, cardiac output, stroke volume, and vascular resistance were measured during rest, mental arithmetic, and reaction time. Compared to low risk subjects, the high risk men had significantly higher blood pressures accompanied by higher vascular resistances at rest and during mental stress. The groups had negligible differences in heart rate, stroke volume, and cardiac output. This pattern of results implicates vascular resistance as the dominant element in altered blood pressure control in these young men at high risk for hypertension.

Stress-like adrenocorticotropin responses to caffeine in young healthy men.

The effects of oral caffeine (3.3 mg/kg, equivalent to 2-3 cups of coffee) on plasma adrenocorticotropin (ACTH) and cortisol (CORT) were tested in 47 healthy young men at rest in a double-blind, placebo-controlled, crossover study. Following caffeine, ACTH was significantly elevated at all times from 30 min to 180 min, and CORT was elevated from 60 min to 120 min (Fs > or = 8.4, ps < 0.01). Peak increases relative to placebo were: ACTH, 33% (+5.2 pg/ml) and CORT, 30% (+2.7 micrograms/dl) at 60 min postcaffeine. The results suggest that caffeine can activate important components of the pituitary-adrenocortical response in humans during the resting state. Caffeine's known ability to increase CORT production appears at least partly due to an increase in ACTH release at the pituitary.

Pain perception and cardiovascular responses in men with positive parental history for hypertension.

Evidence suggests a reduced pain sensitivity in hypertensive individuals. This study sought to extend this work to normotensive individuals with hypertensive parents. Men with a positive (PH+) or negative (PH-) parental history for hypertension rated their pain every 15 s during a 90-s hand cold pressor test and for 90 s after the cold pressor test. Systolic (SBP) and diastolic (DBP) blood pressures and heart rate were measured throughout. After the cold pressor test, the men recalled their pain using the McGill Pain Questionnaire. PH+ men showed greater SBP and DBP responses to the cold pressor test. Although pain ratings during the cold pressor test did not differ between groups, posttest reported pain receded faster in the PH+ than in the PH- men. The PH+ men also reported less total pain on the McGill. These findings support the hypothesis that risk for hypertension may be associated with attenuated pain responses to nociceptive stimuli.

Caffeine and behavioral stress effects on blood pressure in borderline hypertensive Caucasian men.

Caffeine in dietary amounts raises blood pressure (BP), and its use increases during work stress; however, caffeine combined with behavioral stress has not been tested in borderline hypertensive (BH) men. Accordingly, this study tested a psychomotor stressor plus caffeine (3.3 mg/kg, equivalent to 2-3 cups of coffee) using a double-blind, crossover design in 24 BH men (140/90 mmHg < or = BP < or = 160/95 mmHg) and 24 controls (BP < or = 135/85 mmHg). BH men had modestly larger BP increases to the task and showed a greater combined effect of caffeine plus the task (+15/+11 mmHg) than controls (+10/+6 mmHg). BH men maintained response to the stressor in the face of an exaggerated BP response to caffeine, suggesting that use of caffeine during behavioral stress may elevate BP in BH individuals to a clinically meaningful degree.

Hypertension risk factors and cardiovascular reactivity to mental stress in young men.

Hypertension risk may be associated with increased pressor response to mental stress. However, studies using family history as a predictor of reactivity have obtained mixed results. We assessed cardiovascular responses to mental arithmetic stress (a 5-min serial subtraction task) in male medical students (n = 220) at three levels of hypertension risk based on parental history and the subject's systolic blood pressure (SBP): low (SBP < 125 mm Hg and 0 or 1 hypertensive parent), moderate (resting SBP > or = 125 mm Hg or 2 hypertensive parents), or high (resting SBP > or = 125 mm Hg and 1 or 2 hypertensive parents). High risk men showed the greatest blood pressure responses (+22/+16 mm Hg), while moderate and low-risk groups showed correspondingly smaller responses (+17/+13 and +14/+11 mm Hg, p's < 0.02). Family history alone did not predict differential reactivity. This study replicates and extends our previous work suggesting the importance of using both family history and resting blood pressure level in determining future risk for hypertension in studies of cardiovascular reactivity in relation to hypertension risk in males.

Adrenocortical effects of caffeine at rest and during mental stress in borderline hypertensive men.

We examined the effect or dietary doses of caffeine (3.3 mg/kg, equivalent to 2 to 3 cups of coffee) on adrenocortical responses to behavioral stress in borderline hypertensive (BH) men using a randomized, double-blind, caffeine-placebo crossover design. Cortisol levels were assessed in BH men and matched normotensive (NT) controls at rest and in response to 35 min of continuous work on a psychomotor task alternating with mental arithmetic. Caffeine at rest elevated cortisol among BHs hut not among NTs. Both groups showed significant cortisol responses to caffeine combined with the tasks. These findings may have implications for the dietary use of caffeine in persons at risk for hypertension when faced with stressful situations.