Simultaneous reflectometry and interferometry for measuring thin-film thickness and curvature

A coupled reflectometer-interferometer apparatus is described for thin-film thickness and curvature characterization in the three-phase contact line region of evaporating fluids. Validation reflectometry studies are provided for Au, Ge, and Si substrates and thin-film coatings of SiO₂ and hydrogel/Ti/SiO₂. For interferometry, liquid/air and solid/air interferences are studied, where the solid/air samples consisted of glass/air/glass wedges, cylindrical lenses, and molded polydimethylsiloxane lenses. The liquid/air studies are based on steady-state evaporation experiments of water and isooctane on Si and SiO₂/Ti/SiO₂ wafers. The liquid thin-films facilitate characterization of both (i) the nano-scale thickness of the absorbed fluid layer and (ii) the macro-scale liquid meniscus thickness, curvature, and curvature gradient profiles. For our validation studies with commercial lenses, the apparatus is shown to measure thickness profiles within 4.1%-10.8% error.

Nuclear corrections in neutrino-nucleus deep inelastic scattering and their compatibility with global nuclear parton-distribution-function analyses

We perform a global χ² analysis of nuclear parton distribution functions using data from charged current neutrino-nucleus (νA) deep-inelastic scattering (DIS), charged-lepton-nucleus (ℓ(±)A) DIS, and the Drell-Yan (DY) process. We show that the nuclear corrections in νA DIS are not compatible with the predictions derived from ℓ(±)A DIS and DY data. We quantify this result using a hypothesis-testing criterion based on the χ² distribution which we apply to the total χ² as well as to the χ² of the individual data sets. We find that it is not possible to accommodate the data from νA and ℓ(±)A DIS by an acceptable combined fit. Our result has strong implications for the extraction of both nuclear and proton parton distribution functions using combined neutrino and charged-lepton data sets.

Tomography of high-energy nuclear collisions with photon-hadron correlations

Within the next-to-leading order (NLO) perturbative QCD (PQCD) parton model, suppression of away-side hadron spectra associated with a high pT photon due to parton energy loss is studied in high-energy heavy-ion collisions. Because of the sharp falloff of the gamma-jet spectrum in momentum imbalance pTjet-pTgamma>0 in NLO PQCD, hadron spectra at large zT=pTh/pTgamma greater than approximately 1 are more susceptible to parton energy loss and therefore are dominated by surface emission of gamma-associated jets with almost no energy loss, whereas small zT hadrons mainly come from the volume emission of jets with reduced energy. These lead to different centrality dependence of the gamma-hadron suppression for different values of zT. Therefore, a complete measurement of the suppression of gamma-triggered hadron spectra allows a true tomographic study of the quark-gluon plasma in high-energy heavy-ion collisions.

Blood pressure dipping and sleep disturbance in African-American and Caucasian men and women

BACKGROUND

Elevated night time/daytime blood pressure (BP) ratios are associated with cardiovascular morbidity and mortality. We evaluated the associations between sleep/awake BP ratios and sleep disturbances.

METHODS

Sleep disturbances were assessed by in-home actigraphy and diary measures for nine nights, and polysomnography (PSG) for two nights; ambulatory BP was measured for at least 48 h. Participants were 186 middle-aged African-American and Caucasian men and women who were free from prevalent myocardial infarction, stroke, history of interventional cardiology procedures, diabetes, and diagnosed apnea or other sleep disorders.

RESULTS

Results showed that the greater the sleep/wake ratios of BP, the more fragmented the sleep, the greater the proportion in stage 1 (light) sleep and the smaller the proportion in rapid eye movement (REM) sleep, and the greater the number of arousals from sleep. These results were independent of age, race, gender, Framingham Risk status, cardiovascular medications, body mass index, and apnea/hypopnea index. Indicators of psychosocial stress were not greater among those with higher sleep/wake BP ratios.

CONCLUSIONS

Findings are consistent with the hypothesis that elevated night time/daytime pressure may be a consequence of poor sleep.

Chronic stress influences cardiovascular and neuroendocrine responses during acute stress and recovery, especially in men

This study tests the influence of chronic stress on cardiovascular and neuroendocrine responses to and recovery from acute stressors and whether the effects are gender specific. Sixty-two healthy, middle-aged persons (50% women) performed mental-arithmetic and public-speaking tasks and relaxed thereafter for 1 hr while their cardiovascular and neuroendocrine function was measured. Participants with higher levels of chronic stress showed lower systolic blood pressure (SBP) and epinephrine (E; men only) and marginally lower levels of norepinephrine (NE) responses to the tasks and showed lower levels of cortisol and marginally lower NE responses during recovery. Relative to women, men had high diastolic blood pressure (DBP) responses to the tasks and high SBP, DBP, and E responses during recovery. Gender differences in cardiovascular disease in midlife may be due to gender differences in the inability to recover quickly, in addition to enhanced acute-stress response.

Influence of estrogen replacement therapy on cardiovascular responses to stress of healthy postmenopausal women

Two experiments were conducted to understand the influence of estrogen exposure on cardiovascular responses to acute stress measured by impedance cardiography. Study I compared stress responses of 29 postmenopausal women who used postmenopausal hormone replacement therapy (HRT) and 29 who did not use HRT. Women who did not use HRT had higher systolic blood pressure and pulse pressure responses to the tasks relative to HRT users. Study 2 compared stress responses of 38 healthy postmenopausal women not initially on HRT who were randomly assigned to transdermal estradiol or placebo treatment for 6-8 weeks. HRT assignment did not influence substantially women's cardiovascular responses to stress. Characteristics correlated with HRT use, not HRT itself, or differences in type, duration, and dosage may account for the discrepancy in results.

Do the daily experiences of healthy men and women vary according to occupational prestige and work strain?

OBJECTIVE

This study evaluated the influence of occupational prestige and work strain on mood, the occurrence of interpersonal conflict, and ambulatory blood pressure and heart rate.

METHODS

Participants were 50 men and 50 women matched for occupational prestige who were healthy and middle-aged and who completed measures of mood and conflict simultaneously with measures of ambulatory blood pressure and heart rate recorded every 30 minutes during waking hours of two workdays and one nonworkday; at the end of each day, overall ratings were made. Work strain was assessed by the Work Section of the Self-Evaluation and Social Support Interview Schedule. Multiple level random regression coefficients analyses were conducted.

RESULTS

Men and women with low-prestige occupations experienced more interpersonal conflict, b = -0.03, p = .04, and higher ambulatory heart rate, b = -4.83, p = .004, throughout the three days of the study. Relative to those with low work strain, those reporting high work strain experienced negative emotion, b = -0.41, p < .0001, and boredom, b = -0.17, p < .0004. End of the day ratings of negative mood were more influenced by work strain among men than among women. No effects of occupational prestige or work strain were obtained for ambulatory blood pressure readings after adjustment for physical activity, posture, and location.

CONCLUSIONS

Individuals in low-prestige occupations experience greater exposure to interpersonal conflict and arousal as indexed by heart rate, which might increase risk for stress-related illnesses often associated with social class. Individuals who report work strain experience negative mood and boredom, both at work and at home. The absence of work effects on ambulatory blood pressure may be due to the participants being healthy.

Effects of hostility on ambulatory blood pressure and mood during daily living in healthy adults

This study (a) tested the effects of hostile attributes on ambulatory blood pressure (BP), heart rate, and mood monitored repeatedly over 3 days in 100 healthy men and women and (b) determined whether the cardiovascular effects of trait hostility were moderated by mood. Multilevel random-coefficients regression analyses showed that hostile individuals exhibited higher systolic and diastolic BP and rated their current moods as more negative and less positive throughout the monitoring. Individuals low in hostility exhibited high BP only during the few occasions when they experienced negative mood. However, these patterns were true only when participants were classified by Potential for Hostility ratings from the Structured Interview (R. H. Rosenman, 1978), not by the Cynical Hostile Attitudes score derived from the Cook-Medley scale. Results provide convergent and ecological validity of interview rating of hostility and illuminate one possible dynamic mechanism by which overt hostile behaviors might contribute to the rates of increased cardiovascular morbidity and mortality.

Optimism and rehospitalization after coronary artery bypass graft surgery

OBJECTIVE

To determine whether optimism predicts lower rates of rehospitalization after coronary artery bypass graft surgery for the 6 months after surgery.

METHODS

A prospective, inception cohort design was used. The sample consisted of all consenting patients (N=309) from a consecutive series of patients scheduled for elective coronary artery bypass graft surgery at a large, metropolitan hospital in Pittsburgh, Pa. To be eligible, patients could not be scheduled for any other coincidental surgery (eg, valve replacement) and could not be in the cardiac intensive care unit or experiencing angina at the time of the referral. Participants were predominantly men (69.9%) and married (80.3%), and averaged 62.8 years of age. Recruitment occurred between January 1992 and January 1994.

RESULTS

Compared with pessimistic persons, optimistic persons were significantly less likely to be rehospitalized for a broad range of aggregated problems (including postsurgical sternal wound infection, angina, myocardial infarction, and the need for another bypass surgery or percutaneous transluminal coronary angioplasty) generally indicative of a poor response to the initial surgery (odds ratio=0.50, 95% confidence interval=0.33- 0.76; P=.001). The effect of optimism was independent of traditional sociodemographic and medical control variables, as well as independent of the effects of self-esteem, depression, and neuroticism. All-cause rehospitalization also tended to be less frequent for optimistic than for pessimistic persons (odds ratio=0.77, 95% confidence interval=0.57-1.05; P=.07).

CONCLUSIONS

Optimism predicts a lower rate of rehospitalization after coronary artery bypass graft surgery. Fostering positive expectations may promote better recovery.

Effects of optimism, pessimism, and trait anxiety on ambulatory blood pressure and mood during everyday life

This study tested whether dispositional measures of optimism, pessimism, and anxiety affected ambulatory blood pressure (BP) and mood and whether any cardiovascular effects of dispositions were moderated by mood. Pessimistic and anxious adults had higher BP levels and felt more negative and less positive than did optimists or low anxious adults throughout the monitoring. The few times that optimists did feel negative were associated with levels of BP as high as those observed among pessimists or anxious individuals, regardless of their mood. To the extent that trait anxiety measures neuroticism, these findings suggest that neuroticism is directly related to health indicators rather than simply to illness behavior. Furthermore, the results suggest that pessimism has broad physiological and psychological consequences.

Effects of optimism, pessimism, and trait anxiety on ambulatory blood pressure and mood during everyday life

This study tested whether dispositional measures of optimism, pessimism, and anxiety affected ambulatory blood pressure (BP) and mood and whether any cardiovascular effects of dispositions were moderated by mood. Pessimistic and anxious adults had higher BP levels and felt more negative and less positive than did optimists or low anxious adults throughout the monitoring. The few times that optimists did feel negative were associated with levels of BP as high as those observed among pessimists or anxious individuals, regardless of their mood. To the extent that trait anxiety measures neuroticism, these findings suggest that neuroticism is directly related to health indicators rather than simply to illness behavior. Furthermore, the results suggest that pessimism has broad physiological and psychological consequences.

Effects of hostility on ambulatory blood pressure and mood during daily living in healthy adults

This study (a) tested the effects of hostile attributes on ambulatory blood pressure (BP), heart rate, and mood monitored repeatedly over 3 days in 100 healthy men and women and (b) determined whether the cardiovascular effects of trait hostility were moderated by mood. Multilevel random-coefficients regression analyses showed that hostile individuals exhibited higher systolic and diastolic BP and rated their current moods as more negative and less positive throughout the monitoring. Individuals low in hostility exhibited high BP only during the few occasions when they experienced negative mood. However, these patterns were true only when participants were classified by Potential for Hostility ratings from the Structured Interview (R. H. Rosenman, 1978), not by the Cynical Hostile Attitudes score derived from the Cook-Medley scale. Results provide convergent and ecological validity of interview rating of hostility and illuminate one possible dynamic mechanism by which overt hostile behaviors might contribute to the rates of increased cardiovascular morbidity and mortality.

Sleep disturbance in healthy middle-aged women

OBJECTIVES

The objectives of the study were to (a) describe the sleep patterns of a sample of healthy middle-aged women, (b) to characterize the psychological, behavioral and biological profiles of middle-aged women who report sleep disturbance, and (c) to determine the influence of change in menopausal status on the quality and quantity of self-reported sleep.

METHODS

A total of 521 women of varying menopausal status were evaluated in a clinic setting. Measurements included blood pressure, height, weight, waist/hip ratio, and self-reported sleep disturbances, demographic and family characteristics, psychosocial questionnaires, physical activity and nutritional intake. The women who were premenopausal at this initial visit were later evaluated, in an identical protocol, when they became postmenopausal.

RESULTS

A total of 42% of the women reported some type of sleep disturbance. Trouble sleeping was associated with higher levels of anxiety, depression, stress, tension and public self-consciousness. Women with trouble falling asleep had higher systolic and diastolic blood pressures and greater waist/hip ratios. Women who woke earlier than desired had higher systolic and diastolic blood pressures. Sleep disturbance was independent of menopausal status in cross-sectional analyses. In longitudinal analyses, the transition from pre- to postmenopausal status was associated with a significant increase in sleep disturbance in women who chose to not take hormone replacement therapy.

CONCLUSIONS

There is a high level of sleep disturbance in middle-aged women. Sleep disturbance is associated with worse mood, higher blood pressure and higher waist/hip ratios. Transition into postmenopausal status is associated with deleterious changes in sleep patterns among women who do not take hormone replacement therapy.

Are hostility and anxiety associated with carotid atherosclerosis in healthy postmenopausal women?

OBJECTIVE

In this article, we evaluated the prospective association between measures of trait anger, hostility, and anxiety and indices of carotid atherosclerosis in 200 healthy middle-aged postmenopausal women.

METHODS

Starting in 1983, 541 premenopausal women were evaluated for their levels of standard cardiovascular risk factors and psychosocial attributes, including their scores on Spielberger Trait Anger, Anxiety, and Anger-in, and Public Self-Consciousness. Starting in 1991, the Cook-Medley Hostile Attitudes Scale was also administered. Starting in 1993, 200 women who had been menopausal for at least 5 years were scanned for carotid atherosclerosis using B-mode ultrasound. The scans were scored for average intima-media thickness (IMT) and plaque index.

RESULTS

Women who had high Trait Anger, Anger-In, and Public Self-Consciousness scores had high IMT scores on average 10 years later. Women who had high Cook-Medley scores also had high IMT scores on average 1.5 years later. Multivariate analyses adjusting for the standard cardiovascular risk factors that most highly predicted IMT scores indicated that holding anger in, being self aware, and having hostile attitudes were significant predictors of IMT. Women with higher plaque scores also tended to report holding in their anger.

CONCLUSIONS

Anger suppression and hostile attitudes do predict women's carotid IMT in midlife. Ultrasound measures of carotid atherosclerosis can be used to advance our understanding of the early development of atherosclerosis in women.

Stress-induced pulse pressure change predicts women's carotid atherosclerosis

BACKGROUND AND PURPOSE

Individuals who exhibit large increases in blood pressure and heart rate during mental stress may be at risk for accelerated atherosclerosis. This report evaluates the association between stress-induced hemodynamic responses and carotid atherosclerosis in 254 healthy postmenopausal women.

METHODS

The magnitude of change in blood pressure and heart rate from rest to public speaking and mirror image tracing, two stressful tasks, was measured. Average intima-media thickness (IMT) and focal plaque in the common carotid artery, bulb, and internal carotid artery were measured with the use of duplex ultrasonography on average 2.3 years later.

RESULTS

The average IMT was 0.77 mm, with a range of 0.60 to 1.37; 52.5% had at least one plaque. Correlational analysis showed that greater IMT was associated with greater pulse pressure change during mental stress (r = 0.17, P < 0.01). Statistical adjustments for possible confounders (age, hormone replacement therapy use, resting pulse pressure, smoking status, and triglyceride levels) did not alter the results. The plaque index was associated with greater pulse pressure change during the mirror image tracing task (odds ratio = 1.47, P = 0.01) for women with a plaque score of > or = 2 versus 1 or 0, adjusted for possible confounders.

CONCLUSIONS

Mental stress-induced pulse pressure changes may influence the development of early atherosclerosis in the carotid artery of women. Widening of pulse pressure during stress, as well as at rest, may be a marker of compromised compliance in the vessel wall.

Effects of short-term suppression of ovarian hormones on cardiovascular and neuroendocrine reactivity to stress in women

The present study reduced the levels of ovarian hormones to early postmenopausal levels by a GnRH agonist and evaluated the effects of a temporary suppression of ovarian hormones on premenopausal women's cardiovascular and neuroendocrine responses to laboratory challenges. The stress responses of 24 healthy young women were evaluated during three tasks during the early follicular phase and then after three monthly injections of Lupron, which suppressed their levels of estradiol, FSH, and LH. Thereafter, half the group resumed menstrual cycles (labeled Cycle), and half continued having Lupron injections in combination with transdermal estradiol (labeled Patch) and all were reevaluated a third time. A third group (labeled Control) of 12 women had four monthly injections of Lupron first and then were evaluated the first time. After their cycles resumed, they were reevaluated twice 3 months apart. Results showed that the magnitude of the blood pressure and catecholamine changes declined over the three evaluations, suggesting that the women's stress responses habituated. Although the suppression of ovarian hormone levels led to alterations in ovarian hormones for several months, which were accompanied by typical menopausal symptoms, cardiovascular and neuroendocrine responses to stress did not vary. This study did not test the effects of current estrogen exposure or of long term suppression of ovarian hormones upon cardiovascular and neuroendocrine responses.

A natural experiment on the effects of ovarian hormones on cardiovascular risk factors and stress reactivity: bilateral salpingo oophorectomy versus hysterectomy only

To test the effects of declining ovarian hormone levels on cardiovascular risk factors, blood pressure, lipids, weight, and physiological responses to stress were evaluated in 29 middle-aged premenopausal women prior to and following elective hysterectomy and/or bilateral salpingo oophorectomy (BSO). Prior to surgery, there were no group differences in standard or putative risk factors, with the exceptions of body composition measures and total cholesterol level. After surgery, women who had undergone BSO (n = 10) had higher levels of atherogenic lipids and stress-induced lipids and tended to have higher circulating levels of epinephrine and stress-induced systolic and diastolic blood pressure than women who had undergone hysterectomy only (n = 19). This study is consistent with the hypothesis that presence of ovarian hormones plays a key role in determining women's risk factor status.

Sympathetic reactivity to acute stress and immune response in women

We evaluated if the effects of acute stress on immune parameters were apparent in only the women who showed concomitant and substantial sympathetic nervous system activation and after statistical adjustment for changes in plasma volume. Nineteen women in the follicular stage of their menstrual cycles were assessed for immunological responsiveness to a series of three 3-minute psychological tasks, which reliably elicit cardiovascular and neuroendocrine stress responses. Women were classified as high or low sympathetic reactors based on their cardiovascular and neuroendocrine responses to one of the three tasks, a public speaking task. The stress-induced decreases in CD4+ percentage and increases in natural killer cell number and cytolytic activity were only apparent among the high reactors. Further analysis adjusting for alterations in plasma volume changes showed that the increase in NK cell number remained. Stress-induced proliferative responses to pokeweed mitogen and phytohemagglutinin were not more apparent among high reactors. These results are consistent with the hypothesis that the sympathetic nervous system plays a direct role in modulating the short term response to stress of some indices of the immune system in women.

Stress-induced hemoconcentration of blood cells and lipids in healthy women during acute psychological stress

This study examined the effects of psychological stress on hemoconcentration in women. Hematologic and hemodynamic variables were assessed in 17 women before and after a 3-min speech task. Significant changes in hematocrit, hemoglobin levels, red and white blood cell (WBC) count, and calculated plasma volume occurred during psychological stress (all ps < .05). Significant increases were also observed for total cholesterol, triglycerides, high density lipoprotein cholesterol, low density lipoprotein cholesterol, and free fatty acid (FFA; all ps < .05) during stress. After statistically correcting for the hemoconcentration effects of decreased plasma volume during stress, only WBC count and FFA concentration remained significantly elevated during the stress task (p < .006 and p < .05, respectively). In sum, acute stress alters hemoconcentration in women, which in turn can account for most stress-induced changes in lipids.

Stress-induced hemoconcentration of blood cells and lipids in healthy women during acute psychological stress

This study examined the effects of psychological stress on hemoconcentration in women. Hematologic and hemodynamic variables were assessed in 17 women before and after a 3-min speech task. Significant changes in hematocrit, hemoglobin levels, red and white blood cell (WBC) count, and calculated plasma volume occurred during psychological stress (all ps < .05). Significant increases were also observed for total cholesterol, triglycerides, high density lipoprotein cholesterol, low density lipoprotein cholesterol, and free fatty acid (FFA; all ps < .05) during stress. After statistically correcting for the hemoconcentration effects of decreased plasma volume during stress, only WBC count and FFA concentration remained significantly elevated during the stress task (p < .006 and p < .05, respectively). In sum, acute stress alters hemoconcentration in women, which in turn can account for most stress-induced changes in lipids.

Psychological stress and immunological responsiveness in normally cycling, follicular-stage women

Nineteen women in the follicular stage of their menstrual cycles were assessed for immunological responsiveness to a 50-min series of three psychological tasks which reliably elicit cardiovascular and neuroendocrine stress responses. Ten follicular-stage women not subjected to stress served as controls. Stress decreased lymphocyte responsiveness to PHA and PWM, percent of CD4+ cells and the ratio of CD4+/CD8+ cells. Conversely, stress increased natural killer cell number and cytolytic activity, white blood cell, lymphocyte, T and B cell count. Except for natural killer cell number, none of these changes was exhibited by controls. Most of these stress responses are similar to those reported for men and form the basis for a continuing study of the effects of reproductive hormones and stress on cardiovascular and immunological function in women.

Menopausal status influences ambulatory blood pressure levels and blood pressure changes during mental stress

BACKGROUND

Frequent and large cardiovascular and neuroendocrine responses to psychological stress are thought to enhance an individual's risk for cardiovascular diseases. Preliminary data suggest that levels of reproductive hormones affect the magnitude of stress responses, perhaps contributing to the protective effect of ovarian hormones on premenopausal women's rates of coronary heart disease.

METHODS AND RESULTS

Healthy middle-aged men and premenopausal and postmenopausal women performed a series of standardized mental and physical challenges while blood pressure, heart rate, plasma catecholamines, lipids, and lipoproteins were measured. Subjects then wore an ambulatory blood pressure monitor during two consecutive workdays. Results showed that postmenopausal women had larger mean +/- SEM stress-induced increases in systolic blood pressure (24.7 +/- 2.2 mm Hg) and diastolic blood pressure (14.3 +/- 1.0 mm Hg) compared with either premenopausal women (16.9 +/- 1.3 and 10.2 +/- 0.9 mm Hg) or men (17.7 +/- 1.5 and 10.9 +/- 1.1 mm Hg, respectively). Postmenopausal women and men had higher mean +/- SEM ambulatory diastolic blood pressure levels (75.5 +/- 3.2 and 76.4 +/- 1.8 mm Hg) than did premenopausal women (69.9 +/- 2.2 mm Hg). Large blood pressure responses during public speaking were associated with high cholesterol levels and low educational attainment.

CONCLUSIONS

Menopause is associated with enhanced stress-induced cardiovascular responses and elevated ambulatory blood pressure during the workday. These effects may contribute to the risk of cardiovascular morbidity and mortality after the menopause.

Hemodynamic adjustments to laboratory stress: the influence of gender and personality

Exaggerated cardiovascular reactivity to psychological stress is a potential pathophysiological mechanism linking behavior and cardiovascular disease. Because of the recognized gender differences in incidence of cardiovascular disease, potential gender differences in cardiovascular reactivity to laboratory stressors have been evaluated. The current study examined the cardiovascular responses of a total of 42 young women (N = 22) and men (N = 20) undergoing a laboratory protocol including the following: a nonverbal math task, a mirror tracing task, the Stroop Color-Word interference task, and an isometric handgrip task. In addition to the assessment of heart rate and blood pressure, cardiac output, stroke volume, total peripheral resistance and preejection period were assessed by impedance cardiography. A number of personality characteristics that vary in prevalence by gender were also measured to evaluate their ability to explain potential gender differences in cardiovascular responses. Results indicated that men responded with greater total peripheral resistance and systolic and diastolic blood pressure responses than did women on a subset of tasks, whereas women exhibited larger increases in heart rate on a subset of tasks. Thus, men were more likely to be "vascular" reactors, with women being more likely to be "cardiac" reactors. Personality characteristics did differ between men and women, but did not explain significant variance in the gender differences in cardiovascular responses. We conclude that additional studies should focus on experimental manipulations of potential physiological mechanisms responsible for these differences, such as reproductive hormones.

Do cardiovascular responses to laboratory stress relate to ambulatory blood pressure levels?: Yes, in some of the people, some of the time

Because the correspondence between laboratory measures of blood pressure and heart rate responses to stress and ambulatory measures is less than optimal, this study tested two hypotheses: Are ambulatory measures of blood pressure elevated during periods of perceived stress, relative to no stress? Are ambulatory blood pressures elevated during perceived stress among those individuals who exhibit elevated blood pressure and heart rate responses to laboratory stress? These questions were addressed in a sample of employed, middle-aged men and premenopausal and postmenopausal women, who vary in reproductive hormone status, and in risk for coronary heart disease. All participants performed a series of laboratory studies while their physiological parameters were monitored and then wore an ambulatory blood pressure monitor for a day and a half. This monitor recorded blood pressure every half hour during the waking hours and at the same time the participants assessed their mood states. After excluding participants who reported no variability in stress levels, those who were cardiovascular reactors to a laboratory speech task exhibited elevated ambulatory blood pressure levels during periods of perceived stress. Furthermore, in general, periods of perceived stress were associated on a within subject basis with elevated ambulatory blood pressure. These results suggest that the correspondence between laboratory and field measures of blood pressure would be improved by taking into account the environmental circumstances during the ambulatory assessments and the person characteristics of reactor-nonreactor to laboratory stress.

Can physical activity mitigate the effects of aging in middle-aged women?

BACKGROUND

Aging is associated with an increased risk of women dying from coronary heart disease as well as from all causes combined. Alterations in the major biological risk factors for early coronary heart disease and all-cause mortality are frequently seen in aging.

METHODS AND RESULTS

The present investigation tested the hypothesis that high levels of physical activity could protect against age-associated changes in biological risk factor levels. In the Healthy Women Study, 507 women were evaluated at study entry and 3 years later. Weekly physical activity level was measured at each examination via the Paffenbarger Physical Activity Questionnaire. During the 3-year period, women increased significantly in weight, blood pressure, levels of total and low-density lipoprotein cholesterol, triglycerides, and insulin and decreased significantly in levels of total high-density lipoprotein cholesterol (HDL-C) and HDL2-C.

CONCLUSIONS

Consistent with the study hypothesis, women who reported higher levels of activity at baseline had less weight gain over time. Furthermore, women who increased their activity during the 3-year interval had the smallest increases in weight and tended to have the smallest decreases in total HDL-C and HDL2-C. The changes in lipids due to activity were largely independent of changes in body weight.

Does the gender relevance of the stressor influence sex differences in psychophysiological responses?

Sex differences in psychophysiological responses to stress may be important to understanding sex differences in risk for coronary heart disease. This investigation tested the hypothesis that the gender relevance of the stressor influences the extent of sex differences in cardiovascular, neuroendocrine, and lipid responses during stress. Participants performed two tasks that were described as masculine oriented, feminine oriented, or not gender relevant. Although these descriptions influenced the participants' perceptions of the tasks, they did not influence the extent of sex differences in physiological responses in a manner consistent with the study hypothesis. Future directions for research are discussed regarding sex differences in psychophysiological responses.

T-lymphocyte reactivity during the menstrual cycle in women

Reactivity of blood lymphocytes to nonspecific mitogenic stimulation with phytohemagglutinin (PHA) was measured in nine healthy, regularly cycling women at three phases of their menstrual cycles corresponding to peak levels of estradiol (midfollicular phase), peak levels of progesterone (midluteal phase), and the lowest levels of both hormones (menstrual phase). Sampling points were verified by radioimmunoassay of estrogen, progesterone, luteinizing hormone, and follicle-stimulating hormone. There were significant increases in reactivity associated with an increasing concentration of PHA and with autologous plasma vs AB plasma. However, no differences were found in reactivity to PHA over the three menstrual cycle phases and correlational analyses indicated no relationship between counts and any of the hormones measured.

Physical activity and cardiovascular risk: a cross-sectional study of middle-aged premenopausal women

The relationship between self-reported physical activity and cardiovascular risk factors was evaluated in a population-based sample. The sample included 541 premenopausal women recruited for a study of the natural history of risk factor change associated with change in sex hormone status. Physical activity was assessed using the Paffenbarger Activity Questionnaire. Women were classified according to quartile of weekly energy expenditure into groups of 0-500, 501-999, 1,000-1,999, and 2,000 kcal or greater. Results showed that the more active the women, the lower their blood pressure and heart rate. More active women had lower cholesterol and triglycerides, and higher high-density lipoprotein (HDL) cholesterol. Tricep and suprailiac skinfolds, fasting insulin, and insulin/glucose levels were also lower among the more active women. When the analysis was repeated controlling for the effect of education and body mass index, the statistical test for linear trend remained significant except for the trend for heart rate, total cholesterol, and triglycerides. Women reporting activity of 1,000 kcal/week had higher high-density lipoprotein cholesterol and lower diastolic blood pressure, body mass index, skinfolds, fasting insulin, and fasting insulin/glucose ratios compared with women reporting lower levels of activity. Only those women who reported 2,000 kcal/week had significantly lower total cholesterol, triglycerides, and low-density lipoprotein cholesterol, and higher HDL2 cholesterol; women reporting less activity did not differ with regard to these lipids and lipoproteins. The study suggests that physical activity is associated with improved cardiovascular risk profiles among middle-aged women and that the beneficial effects of activity are seen at different levels for specific risk factors.

Influences of the normal menstrual cycle on physiologic functioning during behavioral stress

The purpose of this study was to evaluate the influence of the normal menstrual cycle on lipoprotein, cardiovascular, and neuroendocrine stress responses. Fifteen normally-cycling, healthy women participated in a series of behavioral tasks during the menstrual, follicular, and luteal phases of their menstrual cycle. These women had established menstrual cycle regularity for the three months prior to enrollment in this study, were free from menstrual cycle disturbances, biochemically confirmed that they ovulated, and displayed appropriate patterns of reproductive hormone fluctuations during the study period. Heart rate, blood pressure, low density lipoprotein-cholesterol, and total cholesterol all demonstrated significant elevations from baseline levels during tasks. No differences in the magnitude of stress responses during the three menstrual cycle phases were noted for any physiological variable. We conclude that the hormonal fluctuations that occur in healthy, normally-cycling women during the menstrual cycle do not influence the stress responses that were investigated here. Significant influences of menstrual cycle phase previously reported in the literature, albeit not in a consistent direction, may have been due to the recruitment of women with menstrual cycle irregularities, and to the failure to adequately verify menstrual cycle phase.

Dispositional optimism and recovery from coronary artery bypass surgery: the beneficial effects on physical and psychological well-being

The effect of dispositional optimism on recovery from coronary artery bypass surgery was examined in a group of 51 middle-aged men. Patients provided information at three points in time--(a) on the day before surgery, (b) 6-8 days postoperatively, and (c) 6 months postoperatively. Information was obtained relating to the patient's rate of physical recovery, mood, and postsurgical quality of life. Information was also gathered regarding the manner in which the patients attempted to cope with the stress of the surgery and its aftermath. As expected, dispositional optimism proved to be an important predictor of coping efforts and of surgical outcomes. More specifically, dispositional optimism (as assessed prior to surgery) correlated positively with manifestations of problem-focused coping and negatively with the use of denial. Dispositional optimism was also associated with a faster rate of physical recovery during the period of hospitalization and with a faster rate of return to normal life activities subsequent to discharge. Finally, there was a strong positive association between level of optimism and postsurgical quality of life at 6 months.