Predictors of milk cortisol in North American women.

OBJECTIVES: Human milk content varies across mother-child dyads, environments, and populations. Among the hormones in milk is cortisol, a glucocorticoid; its impact on the breastfeeding child is unknown. Milk cortisol may constitute a signal to the child's developing physiology which can shape characteristics (e.g., growth, temperament) to prevailing environmental conditions. This exploratory study evaluated the maternal, breastfeeding, and infant characteristics associated with milk cortisol. METHODS: We evaluated archived milk specimens for cortisol using enzyme immunoassay and employed an information-theoretic approach to assess associations between milk cortisol and participant characteristics with linear regression modeling. Because we employed secondary data, information for some variables likely to impact milk cortisol variation (e.g., time of day, socioeconomic status, maternal or infant body mass index, milk energy density) was unavailable. RESULTS: Participants were 48 lactating mothers from upstate New York, aged 21-40 years. Milk cortisol ranged from 0.098 to 1.007 µg/dL. Child age ranged from 1 to 26 months. In linear regression employing best fit modeling criteria, milk cortisol increased with child age (B: 0.069; p: .000; a 7.1% increase in milk cortisol for each month of child age), while child symptoms of illness (B: -0.398; p: .057; a 33% decrease) and consumption of complementary foods (B: -.525; p: .020; a 41% decrease) were associated with lower milk cortisol. CONCLUSIONS: We speculate that increasing milk cortisol with child age plays a role in signaling development (e.g., as increasing independence increases risk for injury and other negative health outcomes), independent of the maternal stressors we could capture.

Vaping behaviour patterns and daily blood pressure and heart rate variation: a brief report.

BACKGROUND: Vaping, the use of an electronic device to deliver a drug-infused aerosol has become an increasingly popular way to consume nicotine since its introduction to the market in the early 2000s. Despite the differences in consumption patterns relative to combustible tobacco, the impact of ad libitum nicotine vaping on cardiovascular response has not been thoroughly studied. SUBJECT AND METHODS: This research was conducted on vapers (n = 17) and smokers (n = 14) who represent a subsample of a larger study that explored the relationship between nicotine use, activities of daily living and 24-hour cardiovascular response using Spacelabs ambulatory blood pressure monitors. These data were analysed via ANOVA models and t-tests using SPSS 25.0 for Macintosh. RESULTS: Vapers consumed nicotine significantly more frequently than did smokers, at 48.2% and 18.1% of every 15-minute waking measurement, respectively (p = 0.000). The act of nicotine consumption, rather than the mode of delivery, was significantly associated with increases in systolic, diastolic, mean arterial pressure, and heart rate readings. There was no difference in the mean amplitude of response to nicotine between vapers and smokers. CONCLUSIONS: This study's strong statistical findings, visually evident on ambulatory blood pressure monitor reports, demonstrated that ad libitum nicotine consumption has an acute, dose-dependent effect on cardiovascular response regardless of whether it is smoked or vaped. However, since vapers consumed nicotine more frequently, future studies should be conducted with larger sample sizes, and controlled for age and comorbidities to improve statistical strength. IMPLICATIONS: This pilot study reveals that, when ad lib consumption is documented and measured, vaping has unique and potentially harmful effects on blood pressure, pulse, and mean arterial pressure. Because nicotine is consumed for much longer stretches, vapers have fewer rest periods between nicotine doses.

Measuring arterial blood pressure in humans: Auscultatory and automatic measurement techniques for human biological field studies.

Human biologists have been examining arterial blood pressure since they began studying the effects of the environment and culture on the health of diverse populations. The Korotkoff auscultatory technique with a trained observer and aneroid sphygmomanometer is the method of choice for blood pressure measurement in many bioanthropological field contexts. Korotkoff sounds (the first and fifth phases) are the preferred determinants of systolic and diastolic pressure, even in infants, children, pregnant women, and the elderly. Training of observers, positioning of individuals, and selection of cuff size are all essential for obtaining standardized measurements. Automatic electronic devices are increasingly being used for blood pressure measurement in human biological studies. The automatic monitors often use the oscillometric method for measuring pressure, but must be validated before use. The emergence of automatic ambulatory blood pressure monitors has opened another avenue of research on blood pressure in human biology, where allostasis and circadian responses to environmental change and real life behavioral challenges can be defined and evaluated, largely because there is now the ability to make multiple measurements over time and in varying contexts. Stand-alone automatic monitors can also be substituted for manual auscultated readings in field contexts, although in studies where participants measure their own pressure, education about how the devices work and protocol specifics are necessary. Finally, computer-driven plethysmographic devices that measure pressure in the finger are available to evaluate short-term reactivity to specific challenges.

The consistency of circadian blood pressure and heart rate patterns over three months in women employed in sedentary office jobs.

OBJECTIVES: The purpose of this study was to evaluate the consistency of the circadian patterns of blood pressure (BP) and heart rate (HR) variation over a three-month time frame in women employed outside the home. METHODS: The subjects were 157 healthy women of varying ethnicity (age = 38.2 ± 8.9) who all worked in similar positions at two major medical centers in New York City. Each wore an ambulatory BP monitor during the course of three mid-week work days approximately one month apart. Hourly BPs and HRs were calculated from 9 am to 6 am the following morning and compared among the three days using anova and t tests. RESULTS: The results indicate that there were virtually no differences in the mean hourly levels of any parameter during the waking period across the three days of assessment. However, mean hourly levels of systolic BP significantly declined from 12 pm to 4 am (P < .04, P = .001, P < .001, P = .001, P = .009, respectively) on the third assessment day compared to the first. CONCLUSIONS: Because BP and HR respond to environmental demands in an allostatic fashion, the consistency in the waking patterns of BP and HR variation suggest that the patterns of demands on a workday are reasonably stable in this sample of women. The decline in systolic pressures from 12 pm to 4 am over the three assessments may indicate an improving ability to sleep with the monitor over time.

Understanding Blood Pressure Variation and Variability: Biological Importance and Clinical Significance.

Variability is a normative property of blood pressure necessary for survival which likely contributes to morbidity and mortality through allostatic load. Because of its allostatic and adaptive properties blood pressure responses to peculiar situations like the visit to the clinic can lead to the misdiagnosis of hypertension. Cuff methods of blood pressure measurement can also create blood pressure variation when there really is none. There are also physiological differences between populations related to their evolutionary history that likely further affect the extent of population differences in 24-h blood pressure variability. Quantifying the sources and extent of blood pressure variability can be done using natural experimental models and through the evaluation of ecological momentary data. It is very likely that the results of population studies of blood pressure variability and morbidity and mortality risk are inconclusive because the parameters used to assess blood pressure variability do not reflect the actual nature of blood pressure allostasis.

Ethnic differences in inter- and intra-situational blood pressure variation: Comparisons among African-American, Hispanic-American, Asian-American, and European-American women.

OBJECTIVES: The purpose of this study was to compare the daily inter- and intra-situational ambulatory blood pressure (BP) variation by ethnicity in women. METHODS: The African-American (N = 82; Age = 39.7 + 8.9), Hispanic-American (N = 25; age = 37.5 + 9.4), Asian-American (N = 22; Age = 35.2 + 8.6), and European-American (N = 122; Age = 37.2+ 9.4) women in this study all worked in similar positions at two major medical centers in NYC. Each wore an ambulatory monitor during the course of one mid-week workday. Proportional BP changes from work or home to sleep, intra-situational BP variation (standard deviation [SD]) and mean situational BP levels were compared among the groups using ANOVA models. RESULTS: African-American and Asian-American women had significantly smaller proportional work-sleep systolic changes than either European- (P < 0.05) or Hispanic-American (P < 0.05) women, but the Asian-American women's changes tended to be smallest. The variability (SD) of diastolic BP at work was significantly greater among African- and Hispanic-American women compared to Asian- and European-American women (all P < 0.05). African-American women had greater sleep variability than European-American women (P < 0.05). Asian-American women had the highest level of sleep diastolic pressure (all comparisons P < 0.05). CONCLUSIONS: African-American and Asian-American women have an attenuated proportional BP decline from waking environments to sleep compared to European-American and Hispanic-American women. Asian-American nocturnal BP may be elevated relative to all other groups. Am. J. Hum. Biol. 28:932-935, 2016. © 2016Wiley Periodicals, Inc.

Daily environmental differences in blood pressure and heart rate variability in healthy premenopausal women.

OBJECTIVES: As daily environments change, behavior and activity also change and as blood pressure (BP) and heart rate (HR) are allostatically tied to these factors, one might expect that environments that elicit the greatest behavioral/activity variation should also evince the highest BP and HR variability [standard deviation (SD) or coefficient of variation (CV)]. The purpose of this study was to evaluate this premise. METHODS: Two hundred and six women (age = 37.6 ± 9.1 years) wore an ambulatory BP monitor on a midweek workday. All worked in clerical, technical, or professional positions. Ambulatory BP and HR Means, SDs and CVs at work (11 AM-3 PM), home (∼6-10 PM) and during sleep (∼10 PM-6 AM) were compared using repeated measures ANCOVA. RESULTS: Mean BP and HR decreased from work and home to sleep [121 ± 11, 120 ± 11 vs. 107 ± 12 systolic; 82 ± 10, 80 ± 11 vs. 66 ± 11 diastolic; 79 ± 12, 80 ± 12 vs. 68 ± 11 HR (all P < 0.001)], while the CV of systolic and diastolic BP increased [0.06 ± 0.02, 0.07 ± 0.02 vs. 0.08 ± 0.03 systolic; 0.09 ± 0.03, 0.10 ± 0.04 vs. 0.12 ± 0.05 diastolic (P < 0.001)]. The HR SD decreased during sleep [8.1 ± 3.8, 8.2 ± 3.8 vs. 6.9 ± 3.2 (P < 0.001)]. CONCLUSIONS: HR variability follows the expected variability pattern with behavior and activity, whereas BP does not.

Denial is associated with higher ambulatory blood pressure across the menstrual cycle.

BACKGROUND: Studies show that stress perception is associated with increased daily ambulatory blood pressure (BP) and that denying the negative effects of stress increases BP as well. Whether these effects persist over the menstrual cycle is unknown. AIM: To examine the effects of measures of stress and stress denial on ambulatory work and home BP during the follicular and luteal phases of the menstrual cycle. SUBJECTS AND METHODS: Seventy-one women (age = 34.9 ± 7.7 years) employed as secretaries or technicians wore an ambulatory BP monitor during the follicular (between day 7-10; Mean = 8 ± 2) and luteal (between day 19-25; Mean = 22 ± 2) phases of their cycle. During each phase, relationships between BPs averaged at work and home and various stress measures and demographic and anthropometric variables were examined using stepwise regression. RESULTS: Ambulatory BPs did not change from the follicular to luteal phase. Stress denial was generally associated with higher ambulatory BP (p < 0.05) over the menstrual cycle, while other parameters had varying effects in different situations (work and home) and cycle phases. CONCLUSION: Stress denial has a persistent effect on BP, regardless of menstrual phase; however, shifts in the hormonal environment throughout the menstrual cycle may mediate other somatic and behavioural associations with BP.

Differential circadian catecholamine and cortisol responses between healthy women with and without a parental history of hypertension.

OBJECTIVES: Previous studies suggest that otherwise healthy individuals who have a parental history of hypertension (PH+) have an accentuated reactive rise in catecholamines and cortisol to laboratory stressors as well as elevated plasma levels when compared with those with no parental history (PH-); however, few, if any, studies have evaluated whether parental history affects the responses of these hormones to changing environmental circumstances in everyday life. The purpose of this study was to compare urinary catecholamine (epinephrine and norepinephrine) and cortisol excretion and ambulatory blood pressures (BPs) across three daily microenvironments between women with and without a parental history of hypertension. METHODS: The women in the study (PH+, N = 62, age = 35.2 ± 9.1; PH-, N = 72, age = 33.8 ± 10.0) worked in clerical, technical, or professional positions at a major medical center in New York City. Urinary hormone excretion rates and ambulatory BP were measured across three daily microenvironments: work (11 am to 3 p.m.), home (approximately 6 p.m. to 10 p.m.), and during sleep (approximately 10 p.m. to 6 a.m.). History group comparisons by microenvironment were made using repeated-measures ANCOVA and ANOVA analyses. RESULTS: The results show that epinephrine excretion among PH+ women was 36% higher than PH- women (P < 0.008) over the entire day and that nocturnal cortisol excretion was also greater among PH+ women (P < 0.045). PH+ women also had statistically significantly higher systolic (4 mm Hg higher; P < 0.01) and diastolic (2 mm Hg higher, P < 0.03) BP when compared with PH- women across all daily microenvironments. CONCLUSION: These findings suggest that there may be genetically linked mechanisms which elevate tonic epinephrine levels and nocturnal cortisol levels that contribute to elevating circadian BP.

Relationships between diurnal changes in blood pressure and catecholamines among Filipino-American and European-American women.

OBJECTIVES: Studies show that diurnal blood pressure (BP) sensitivity to epinephrine (EPI) in African-American women is significantly greater than that of European-American (EA) women. Few if any studies have examined diurnal catecholamine-BP relationships in women of other ethnic groups. The purpose of this study was to compare the effects of diurnal changes in EPI and norepinephrine (NE) on the diurnal changes in BP between Filipino-American (FA) and EA women. METHODS: The subjects included 31 FA and 27 EA nurses and nurses aides and eight FA and 19 EA hotel workers from Hawaii who wore an ambulatory BP monitor and collected timed urine specimens (4 h at work, approx.4 h at home and approx. 8 h overnight) for assay of EPI and NE. Proportional changes in systolic and diastolic BP from sleep to work and sleep to home were examined using ANCOVA models including fixed effect-covariate interactions, with ethnicity as a fixed factor, and BMI and the appropriate proportional change in EPI or NE as covariates. RESULTS: The results show that there was no association between changes in EPI and BP, either overall or by ethnic group; however, overall changes in diastolic BP from sleep to work tended to be smaller among the FAs (P < 0.06). There was also an interactive effect of NE and ethnic group on diastolic BP such that among FAs, as diastolic BP increased, the corresponding NE change decreased (P < 0.039). CONCLUSION: The relationships between diurnal BP and catecholamine variations differ by ethnicity. Further research is needed to better understand the mechanisms behind the differences and to evaluate whether this vascular tonic relationship has been the focus of natural selective processes.

Ambulatory blood pressure and blood lipids in a multiethnic sample of healthy adults.

OBJECTIVES: Elevated blood pressure (BP), elevated serum cholesterol, and aberrant lipoprotein fractions (low levels of high-density lipoprotein (HDL) and high levels of low-density lipoprotein fractions and triglycerides) have all been used as measures that assess the "metabolic syndrome" and more recently in indexes of allostatic load, which are designed to assess the degree of integrated metabolic pathology. While there are ample data regarding the interrelationships of these measures in various pathophysiological settings, there are limited data regarding the interrelationship of ambulatory BP (ABP) and blood lipids in healthy subjects. The present study evaluates ABP-blood lipid relationships in a multiethnic sample of healthy adults. METHODS: The subjects were 37 men (age = 40.9 ± 10.7 years) and 42 women (age = 35.8 ± 10.4 years) who were employed as hotel workers in Hawaii. Each wore an ABP monitor for one midweek workday and had pressures averaged in three daily microenvironments (work, home, and during sleep). They also had fasting blood samples taken for lipid profiling. RESULTS: Multivariate analysis of covariance shows that there was a strong inverse relationship between HDL and both systolic (P < 0.006) and diastolic (P < 0.006) BP, overall and in each microenvironment, but no statistically significant relationships with other lipid measures. CONCLUSION: These results suggest lipids and BP do not act as a group in healthy adults but that higher HDL is associated with lower BP. This latter finding is consistent with research that shows that HDL promotes vasodilation via its effect on endothelial nitric oxide synthase.

The effects of smoking cessation and a programme intervention on birth and other perinatal outcomes among rural pregnant smokers.

OBJECTIVE: The purpose of this study was to evaluate the perinatal outcomes of rural pregnant smokers enrolled in the Smoke Free Baby & Me trial. METHODS: Data on smoking status and other pre-natal variables were collected during pregnancy. Outcomes were retrieved from a review of hospital records of 161 singleton births (79 from the control group, 82 from the intervention group). RESULTS: The results show that, after adjusting for gender and gestational age, the more self-reported cigarettes at the first pre-natal visit, the less the infant birth weight (p = 0.033), the less maternal weight gain (p = 0.042) and the shorter the labour length (p = 0.041). Infants of women with positive urinary cotinine at the first pre-natal visit in the intervention group had higher 1 minute Apgar scores than those with negative cotinine (p = 0.022). Smokers also had a preponderance of male infants (64% vs 36%), while non-smokers had more females (59% vs 41%) (p = 0.006). CONCLUSIONS: Smoking during pregnancy affects perinatal outcomes. Assuming a foetal origin of chronic disease morbidity, implementing smoking cessation during pregnancy would not only improve maternal and foetal health, but also might contribute to an improvement in the incidence of adult chronic disease morbidity.

The impact of child-rearing status on perceptual and behavioural predictors of ambulatory blood pressure variation among working women.

BACKGROUND: Past studies have shown that diurnal blood pressure varies between working women with and without children. Understanding of how perceptual and behavioural factors affect this relationship is limited. AIM: The study aim was to evaluate whether perceptions and behaviours differentially influenced ambulatory blood pressure variation across changing daily environments between working women with and without children. SUBJECTS AND METHODS: Women (83 with children, 157 without) working as secretaries or technicians were studied. Anthropometric, demographic, questionnaire and ambulatory blood pressure data were collected. Principal component analysis was utilized to create perceptual and behavioural factors from questionnaire items. Sequential stepwise regression and MANCOVA analyses were used to model blood pressure variation. RESULTS: Diurnal levels and variation in ambulatory blood pressures were similar between women with and without children. Those with children were older, shorter, heavier; more ethnically diverse, had a smaller social support network, perceived less stress and difficulty on the job and reported a better balance between work and home responsibilities then women without children (all significant at p < 0.05). Perceptual and behavioural predictors of work, home and sleep blood pressures differed between the groups. CONCLUSION: There are significant differences in biological and behavioural predictors of ambulatory blood pressure between women with and without children.

The Development and Testing of a Perinatal Tobacco Attitudes and Behaviors Survey.

Background and Purpose: Accurate assessment of tobacco use in pregnant smokers is key to effective nursing intervention. There is a lack of valid and reliable tools easily integrated into prenatal care. Therefore, the purpose of this study was to develop and test a perinatal survey, guided by the Health Promotion Model (HPM). Methods: The survey was tested with 107 pregnant women via iPad. Urine cotinine assays and a process evaluation were conducted. Results: Reliability yielded a Cronbach's alpha of .873 for the ever-smoker sample and .835 for the total sample. Factors dovetailed with HPM constructs. Conclusions: Perinatal Tobacco Attitudes and Behaviors Survey (PTABS) exhibits high reliability and validity and is easily utilized. Updates need to include questions on all nicotine products and to be streamlined. With accurate identification of nicotine users nurses can provide targeted interventions early in pregnancy.

The reproducibility of ethnic differences in the proportional awake-sleep blood pressure decline among women.

A growing body of evidence indicates that African Americans (AA), on average, have a smaller proportional decline in blood pressure (BP) from waking to sleep than European Americans (EA), but this difference is largely based on correlational data from a single assessment day. The persistence of this difference over repeated sampling is not well established. The purpose of this study was to evaluate whether ethnic differences in the awake-sleep BP decline between AA and EA persisted over three monthly assessments. The subjects were 47 AA (age = 39.7 +/- 8.7) and 92 EA (age = 37.4 +/- 9.2) normotensive women. Subjects had 24-h ambulatory BP monitoring done on midweek workdays at 1-month intervals for three consecutive months. The proportional decline in BP was calculated as follows: (average awake - average sleep)/average sleep. The persistence of ethnic differences was evaluated using repeated-measures ANCOVA and by examining Bland-Altman plots. The ANCOVA results revealed that overall, the proportional decline of AA women was less than that of EA women for both SBP (P < 0.038) and DBP (P < 0.083), consistent with previous research, and that there were also no significant ethnic differences by monthly assessment. Bland-Altman plots revealed that overall and by ethnicity, the proportional decline in BP among individual subjects over the 3 months was also reproducible. These results suggest that the ethnic difference in awake-sleep BP between AA and EA women persists over time and that the awake-sleep decline in BP among individuals, whether AA or EA, is also reproducible.

Blood pressure and lifestyle on Saba, Netherlands Antilles.

During the 20th century, infectious disease morbidity and mortality generally waned whereas chronic degenerative diseases posed a growing burden at the global level. The population on Saba, Netherlands Antilles has recently experienced such an epidemiologic transition, and hypertension was reported to be extraordinarily high, although no prevalences have been reported and relationships with lifestyle factors associated with rapid modernization have not been explored. In this study, a medical and demographic questionnaires, as well as body composition and blood pressure measures were collected from 278 Saban men and women aged 18-91 years. When age and sex adjusted, 48% of the population was hypertensive. Age, BMI, and Afro-Caribbean descent were all associated with higher blood pressures. In a second phase, 124 individuals of the 278 were invited to receive a longer questionnaire on individual exposure to modernizing influences such as travel and education. Higher blood pressure was associated with having lived in fewer different places in the past; those who stayed only on Saba or Statia had higher blood pressures than those who had also lived in more modernized areas. However, this was no longer statistically significant after adjustment for age and BMI. Lifestyle incongruity was positively associated with higher blood pressure in that those with more discord between material wealth and income were more likely to be hypertensive, and this remained statistically significant after adjustment for age and adiposity. In summary, hypertension is highly prevalent on Saba and tended to be associated with greater age, adiposity, Afro-Caribbean ancestry, and lifestyle incongruity.

The Adaptive Value and Clinical Significance of Allostatic Blood Pressure Variation.

In recent years, there has been interest in evaluating the morbidity and mortality risk of circadian, diurnal, or nocturnal blood pressure variation. Variation is a normative property of blood pressure, necessary for survival. Like many physiological functions, blood pressure undergoes allostasis, meaning that the body does not defend a particular blood pressure value, but rather blood pressure maintains bodily stability through continual change that is initiated by constantly fluctuating internal and external environmental stimuli. Because of its allostatic and adaptive properties, the blood pressure response to unusual situations like a visit to the clinic can lead to misdiagnosis of hypertension. However, blood pressure variation is mostly ignored when evaluating hypertension, which is an arbitrary dichotomy. Whether variation is indicative of pathology should be determined by assessing its appropriateness for the circumstance, which requires quantification of the sources and extent of normative blood pressure responses to everyday living. These responses will vary among populations due to evolutionary genetic differences. The inconsistency of reports regarding aspects of ambulatory blood pressure variation as cardiovascular risk factors likely results from the fact that the measures used do not reflect the actual nature of blood pressure allostasis.

Higher levels of central adiposity in healthy premenopausal women with family histories of premenopausal breast cancer.

Research strongly suggests that lower overall adiposity and higher central adiposity are independent risk factors for premenopausal breast cancer in the general population. We aimed to test the possibility that these factors may contribute to familial risk of premenopausal breast cancer. A convenience sample of healthy women, ages 25-49, was recruited to yield three study groups: (1) Women with first-degree family histories of premenopausal breast cancer, operationally defined as being diagnosed prior to age 50 (Group FH < 50, n = 39); (2) Women with first-degree family histories of postmenopausal breast cancer, operationally defined as being diagnosed at age 50 or after (Group FH > or = 50, n = 33); and (3) Women without a history of breast cancer in first-degree relatives (Group FH-, n = 132). Multinomial logistic regression analyses, including possible confounders, waist circumference, and BMI, revealed a lower BMI among FH < 50 compared to either FH- (OR = 0.72; 95% CI = 0.59-0.87), or FH > or = 50 women (OR = 0.75; 95% CI = 0.60-0.95), and higher waist circumferences in FH < 50 compared to either FH- (OR = 1.15; 95% CI = 1.06-1.25), or FH > or = 50 women (OR = 1.16; 95% CI = 1.05-1.28). No group differences were seen for waist skinfold measures. These results support the possibility that differences in patterns of adiposity may contribute to familial risk of premenopausal breast cancer, and suggest the importance of conducting large scale, population-based studies of the link between body size characteristics and familial breast cancer risk.

The rate of urinary cortisol excretion at work is persistently elevated in women at familial risk for breast cancer.

We recently reported that healthy women at familial risk for breast cancer (FH+) have higher urinary cortisol levels at work than women without familial risk (FH-). The purpose of this study was to evaluate whether this group difference persisted over a 1-month period. Subjects were healthy women (FH+, N = 42, age = 37.6 +/- 9.3, FH-, N = 93, age 38.4 +/- 9.0) employed primarily in clerical or technical positions at three medical centers in New York City who collected timed urine samples in three contrasting daily environments, at work ( approximately 11AM-3PM), home (approximately 6PM-10PM) and during sleep (approximately 10PM-6AM) on 2 mid-week workdays approximately 1 month apart. Two-way repeated measures ANOVA revealed that cortisol excretion differed across the environments (P < 0.001), and that there was also a significant interaction between daily environment and family history group (P < 0.049), such that FH+ women maintained higher cortisol excretion at work over the 2 days than FH- women. A Bland-Altman plot showed that both overall and by family history group, the rate of cortisol excretion at work was generally reproducible, although there was a heteroscadasticity in the relationship that likely reflected excessive stressfulness on one of the study days in a small minority of subjects. These results suggest that the presence of a potent background stressor (familial breast cancer risk) can influence more acute cortisol responses in daily life over time.

Relationship between waking-sleep blood pressure and catecholamine changes in African-American and European-American women.

BACKGROUND: A blunted decline in waking to sleep blood pressure (BP) is more common in African-American (AA) than European-American (EA) women. The causes of reduced BP 'dipping' in AA women are not known, although several factors including ethnic differences in catecholamine sensitivity have been suggested. The purpose of this study was to investigate the possible contribution of catecholamine influences on BP to ethnic differences in BP dipping in a sample of working women. PARTICIPANTS AND METHODS: Healthy female participants wore ambulatory BP monitors over the course of 1 work day and night. Urine samples for assay of epinephrine and norepinephrine were collected at work (approximately 11.00-15.00 h), home (approximately 06.00-22.00 h) and during sleep (approximately 22.00-06.00 h). Analysis of covariance was used to assess the relationships between changes in BP and the catecholamines by ethnicity. RESULTS: AA women (n=51; age=38.9+/-8.5 years) had smaller proportional BP changes from work to sleep and home to sleep than EA women (n=110; age=37.1+/-9.2 years). Overall, the work to sleep change in epinephrine excretion was positively associated with changes in both SBP (P<0.003) and DBP (P<0.001); however, there was an ethnic difference in the epinephrine-BP relationship. For AA women, these associations were highly positive and significant, but for EA women, there was little correlation. Nonetheless, the analysis also revealed that overall, the work to sleep BP changes were not directly related to ethnic differences in catecholamine variation. CONCLUSION: The AA-EA difference in waking-sleep BP changes (dipping) is not directly related to ethnic differences in catecholamine variation; however, AA seem to have a greater BP sensitivity to epinephrine.