Cortisol and cardiometabolic disease: a target for advancing health equity

The Relationship between Psychological Stress and Anthropometric, Biological Outcomes: A Systematic Review

Background and Objectives: Challenges and threats to global security and the growing demands of today's society lead to significantly increased exposure to stress. Stress can negatively affect numerous physiological processes, including metabolic changes. An unhealthy lifestyle might intensify this disruption. The aim of the systematic review was to establish the effect of psychological stress on metabolic and anthropometric factors in healthy individuals. Materials and Methods: The study was conducted according to the PRISMA guidelines; and the risk of bias (ROB) assessment was based on the Newcastle-Ottawa Scale (NOS). A literature search of the MEDLINE/PubMed database was conducted using specific search terms. Results: We identified 32 articles meeting the inclusion criteria for the review with the different experimental designs and aims. Most of the papers were at high ROB. The included studies were conducted in groups of adults and children/teenagers. The most-often-applied tool to measure stress severity was the Perceived Stress Scale (PSS). Twenty-two studies analyzed the connection between stress and body composition, and bioimpedance analysis (BIA) was the most often used method. For biological parameters, the most frequently analyzed was cortisol (n = 9). The other examined factors included glucose, insulin, parameters related to food intake regulation, carbohydrates, lipid metabolism, inflammation, and oxidative stress. The included studies were incompliance in relation to the assessment method and type of assessed biological fluids. Conclusions: The vast majority of studies do not support the effect of chronic distress on anthropometric measurements and biological markers levels. However, many of them suggest adverse, synergistic effects of unhealthy lifestyle patterns and the stress on the examined variables. Further experiments should implement a similar and repeatable methodology.

Atypical monocyte dynamics in healthy humans in response to fasting and refeeding are distinguished by fasting HDL and postprandial cortisol

Monocytes are innate immune cells that are continuously produced in bone marrow which enter and circulate the vasculature. In response to nutrient scarcity, monocytes migrate back to bone marrow, where, upon refeeding, they are rereleased back into the bloodstream to replenish the circulation. In humans, the variability in monocyte behavior in response to fasting and refeeding has not been characterized. To investigate monocyte dynamics in humans, we measured blood monocyte fluctuations in 354 clinically healthy individuals after a 12-h overnight fast and at 3 and 6 h after consuming a mixed macronutrient challenge meal. Using cluster analysis, we identified three distinct monocyte behaviors. Group 1 was characterized by relatively low fasting monocyte counts that markedly increased after consuming the test meal. Group 2 was characterized by relatively high fasting monocyte counts that decreased after meal consumption. Group 3, like Group 1, was characterized by lower fasting monocyte counts but increased to a lesser extent after consuming the meal. Although monocyte fluctuations observed in Groups 1 and 3 align with the current paradigm of monocyte dynamics in response to fasting and refeeding, the atypical dynamic observed in Group 2 does not. Although generally younger in age, Group 2 subjects had lower whole body carbohydrate oxidation rates, lower HDL-cholesterol levels, delayed postprandial declines in salivary cortisol, and reduced postprandial peripheral microvascular endothelial function. These unique characteristics were not explained by group differences in age, sex, or body mass index (BMI). Taken together, these results highlight distinct patterns of monocyte responsiveness to natural fluctuations in dietary fuel availability.NEW & NOTEWORTHY Our study composed of adult volunteers revealed that monocyte dynamics exhibit a high degree of individual variation in response to fasting and refeeding. Although circulating monocytes in most volunteers behaved in ways that align with previous reports, many exhibited atypical dynamics demonstrated by elevated fasting blood monocyte counts that sharply decreased after meal consumption. This group was also distinguished by lower HDL levels, reduced postprandial endothelial function, and a delayed postprandial decline in salivary cortisol.

Diabetes mellitus-Progress and opportunities in the evolving epidemic

Diabetes, a complex multisystem metabolic disorder characterized by hyperglycemia, leads to complications that reduce quality of life and increase mortality. Diabetes pathophysiology includes dysfunction of beta cells, adipose tissue, skeletal muscle, and liver. Type 1 diabetes (T1D) results from immune-mediated beta cell destruction. The more prevalent type 2 diabetes (T2D) is a heterogeneous disorder characterized by varying degrees of beta cell dysfunction in concert with insulin resistance. The strong association between obesity and T2D involves pathways regulated by the central nervous system governing food intake and energy expenditure, integrating inputs from peripheral organs and the environment. The risk of developing diabetes or its complications represents interactions between genetic susceptibility and environmental factors, including the availability of nutritious food and other social determinants of health. This perspective reviews recent advances in understanding the pathophysiology and treatment of diabetes and its complications, which could alter the course of this prevalent disorder.

The Association of Adiposity and RAAS with Incident Diabetes in African Americans: The Jackson Heart Study

BACKGROUND

The renin-angiotensin-aldosterone system (RAAS) and adiposity measures are independently associated with the development of diabetes in African American (AA) adults. However, studies have not examined the combined interaction between RAAS and adiposity measures in relation to diabetes risk in AA adults.

OBJECTIVE

We examined the longitudinal association of combined RAAS and adiposity measures with incident diabetes among AAs in the Jackson Heart Study.

METHODS

AA adults were assessed at baseline (2000-2004) and over 12 years of follow-up. RAAS, anthropometric (waist circumference [WC], body mass index [BMI]) and adipokine (adiponectin, leptin, leptin: adiponectin ratio [LAR]) measures were collected at baseline. Aldosterone, WC, and LAR were chosen as the best predictor variables. The final model, adjusting for age, sex, education, occupation, systolic blood pressure, smoking, physical activity and RAAS altering medications, incorporated these variables and their interactions (WC*Aldosterone + LAR*Aldosterone) to explore their impact on incident diabetes.

RESULTS

Among 3,220 participants without diabetes at baseline, there were 554 incident cases over a median follow-up of 7.5 years. Aldosterone, WC, and LAR were positively associated with incident diabetes (all p < 0.05). A significant interaction was found between WC and aldosterone with a greater association among individuals with lower WC. This interaction was significant in participants with prediabetes but not in those with normoglycemia. No significant interaction was found between log-LAR and aldosterone with risk of incident diabetes.

CONCLUSION

Higher aldosterone in participants is associated with greater risk of diabetes, particularly among individuals with prediabetes and lower WC.

Tetrandrine inhibits aldosterone synthesis by covalently targeting CYP11A1 to attenuate hypertension

Introduction

Tetrandrine (Tet) is the main pharmacological component of Stephania tetrandra S. Moore, which is a well-documented traditional Chinese medicine known for its diuretic and antihypertensive properties. Unraveling the specific targets and mechanisms of Tet involved in inducing diuresis and mitigating hypertension can provide valuable insights into its therapeutic effects. This study aimed to explore the diuretic and antihypertensive targets and mechanisms of Tet using chemical biology coupled with activity analyses in vivo and in vitro.

Methods

The diuretic effects of Tet were evaluated using a water-loaded mouse model. The direct target proteins for the diuretic and antihypertensive effects of Tet were determined using chemical biology. Furthermore, the molecular mechanism of Tet binding to target proteins was analyzed using a multidisciplinary approach based on the structure and function of the proteins. Finally, the effects of the Tet-targeted protein on downstream signaling pathways and blood pressure were evaluated in hypertensive model rats.

Results

Tet exhibited significant antihypertensive and potassium-preserving diuretic effects. The mechanism underlying these effects involves the modulation of the enzyme activity by covalent binding of Tet to Cys423 of CYP11A1. This interaction alters the stability of heme within CYP11A1, subsequently impeding electron transfer and inhibiting aldosterone biosynthesis.

Discussion

This study not only revealed the mechanism of the diuretic and antihypertensive effects of Tet but also discovered a novel covalent inhibitor of CYP11A1. These findings contribute significantly to our understanding of the therapeutic potential of Tet and provide a foundation for future research in the development of targeted treatments for hypertension.

Health position paper and redox perspectives - Disease burden by transportation noise

Transportation noise is a ubiquitous urban exposure. In 2018, the World Health Organization concluded that chronic exposure to road traffic noise is a risk factor for ischemic heart disease. In contrast, they concluded that the quality of evidence for a link to other diseases was very low to moderate. Since then, several studies on the impact of noise on various diseases have been published. Also, studies investigating the mechanistic pathways underlying noise-induced health effects are emerging. We review the current evidence regarding effects of noise on health and the related disease-mechanisms. Several high-quality cohort studies consistently found road traffic noise to be associated with a higher risk of ischemic heart disease, heart failure, diabetes, and all-cause mortality. Furthermore, recent studies have indicated that road traffic and railway noise may increase the risk of diseases not commonly investigated in an environmental noise context, including breast cancer, dementia, and tinnitus. The harmful effects of noise are related to activation of a physiological stress response and nighttime sleep disturbance. Oxidative stress and inflammation downstream of stress hormone signaling and dysregulated circadian rhythms are identified as major disease-relevant pathomechanistic drivers. We discuss the role of reactive oxygen species and present results from antioxidant interventions. Lastly, we provide an overview of oxidative stress markers and adverse redox processes reported for noise-exposed animals and humans. This position paper summarizes all available epidemiological, clinical, and preclinical evidence of transportation noise as an important environmental risk factor for public health and discusses its implications on the population level.

Plasma metabolite profile of legume consumption and future risk of type 2 diabetes and cardiovascular disease

BACKGROUND

Legume consumption has been linked to a reduced risk of type 2 diabetes (T2D) and cardiovascular disease (CVD), while the potential association between plasma metabolites associated with legume consumption and the risk of cardiometabolic diseases has never been explored. Therefore, we aimed to identify a metabolite signature of legume consumption, and subsequently investigate its potential association with the incidence of T2D and CVD.

METHODS

The current cross-sectional and longitudinal analysis was conducted in 1833 PREDIMED study participants (mean age 67 years, 57.6% women) with available baseline metabolomic data. A subset of these participants with 1-year follow-up metabolomics data (n = 1522) was used for internal validation. Plasma metabolites were assessed through liquid chromatography-tandem mass spectrometry. Cross-sectional associations between 382 different known metabolites and legume consumption were performed using elastic net regression. Associations between the identified metabolite profile and incident T2D and CVD were estimated using multivariable Cox regression models.

RESULTS

Specific metabolic signatures of legume consumption were identified, these included amino acids, cortisol, and various classes of lipid metabolites including diacylglycerols, triacylglycerols, plasmalogens, sphingomyelins and other metabolites. Among these identified metabolites, 22 were negatively and 18 were positively associated with legume consumption. After adjustment for recognized risk factors and legume consumption, the identified legume metabolite profile was inversely associated with T2D incidence (hazard ratio (HR) per 1 SD: 0.75, 95% CI 0.61-0.94; p = 0.017), but not with CVD incidence risk (1.01, 95% CI 0.86-1.19; p = 0.817) over the follow-up period.

CONCLUSIONS

This study identified a set of 40 metabolites associated with legume consumption and with a reduced risk of T2D development in a Mediterranean population at high risk of cardiovascular disease.

TRIAL REGISTRATION

ISRCTN35739639.

A population-based study of children suggests blunted morning cortisol rhythms are associated with alterations of the systemic inflammatory state

BACKGROUND

In children, digital media, lifestyle, and the COVID pandemic have impacted sunlight exposure, exercise, and diet patterns - cues that entrain the circadian clock. We hypothesized that low morning cortisol reflects a weak circadian clock, impacting the pro-inflammatory state. The primary objective was to test relationships between diurnal cortisol fluctuations and the inflammatory state in children as a means of providing indirect support for this hypothesis.

METHODS

The Cardiovascular Health Intervention Program (CHIP) was a population-based cross-sectional and longitudinal study of circadian health in public elementary school children in Southern Maine, USA (recruitment period 2012-2017). Participants were 689 students in 4th grade (baseline; age=9.2 ± 0.4 years), and 647 students in 5th grade (age=10.5 ± 0.5 years). Nine salivary cortisol measures per child (2 awakening and 1 prior to bed for 3 sequential days) (n = 1336 child phenotype days; n = 7987 cortisol assays), 10 cytokines measured in morning and evening saliva samples (n = 202 child phenotype days), and lipids were measured. Clinical outcomes were blood pressure, weight and height (body mass index [BMI]; BMI = kg/m2), among others.

FINDINGS

Upon-waking cortisol levels were 0.28 ± 0.13 µg/dL, 30-minute post-waking 0.33 ± 0.15 µg/dL, and evening 0.08 ± 0.10 µg/dL. Salivary cytokine levels (n = 202) showed interleukins (IL) IL-1β and IL-8 were highest in early morning (upon awakening; AM), and IL-6 and tumor necrosis factor (TNF) TNF-α highest before bed (PM) (IL-1β AM > PM [-4.02 fold; p < 0.001]; IL-8 AM > PM [-1.36 fold; p < 0.001]; IL-6 AM < PM [+1.49 fold; p < 0.001]; TNF-α AM < PM [+1.73 fold; p = 0.03]. Regression modeling showed high morning cortisol was associated with high morning IL-1β (p = 3.82 ×10-6), but low evening IL-1β (p = 6.27 ×10-4). Regression modeling of BMI z-score as the response variable showed the expected significant relationships to high density lipoprotein (HDL) (negative; p < 0.001), mean arterial pressure (positive; p < 0.001), and morning cortisol (negative; p = 0.01) but only weak relationships to either evening cortisol (p = 0.1) or cytokine (positive; p = 0.02; from the model with smallest Rsquared) levels.

INTERPRETATION

We provide preliminary data on diurnal fluctuations of inflammatory cytokines in saliva in a population-based cohort of children. Correlation of morning and evening cortisol levels with inflammatory cytokines in the same saliva samples showed that high morning cortisol was associated with high morning IL-1β and low evening IL-1β. Future studies may test the hypothesis that strong diurnal cycling of IL-1β may serve as a homeostatic mechanism keeping the immune system in check, and that low morning cortisol (possible circadian misalignment) may lead to less stringent control of inflammatory networks.

Adverse Childhood Experiences and BMI: Lifecourse Associations in a Black-White U.S. Women Cohort

INTRODUCTION

Although adverse childhood experiences (ACEs) have been positively associated with adiposity, few studies have examined long-term race-specific ACE-BMI relationships.

METHODS

A Black and White all-women cohort (N=611; 48.6% Black) was followed between 1987 and 1997 from childhood (ages 9-10 years) through adolescence (ages 19-20 years) to midlife (ages 36-43 years, between 2015 and 2019). In these 2020-2022 analyses, the interaction between race and individual ACE exposures (physical abuse, sexual abuse, household substance abuse, multiple ACEs) on continuous BMI at ages 19-20 years and midlife was evaluated individually through multivariable linear regression models. Stratification by race followed as warranted at α=0.15.

RESULTS

Race only modified ACE-BMI associations for sexual abuse. Among Black women, sexual abuse was significantly associated with BMI (Badjusted=3.24, 95% CI=0.92, 5.57) at ages 19-20 years and marginally associated at midlife (Badjusted=2.37, 95% CI= -0.62, 5.35); among White women, corresponding associations were null. Overall, having ≥2 ACEs was significantly associated with adolescent BMI (Badjusted=1.47, 95% CI=0.13, 2.80) and was marginally associated at midlife (Badjusted=1.45, 95% CI= -0.31, 3.22). This was similarly observed for physical abuse (adolescent BMI: Badjusted=1.23, 95% CI= -0.08, 2.54; midlife BMI: Badjusted=1.03, 95% CI= -0.71, 2.78), but not for substance abuse.

CONCLUSIONS

Direct exposure to certain severe ACEs is associated with increased BMI among Black and White women. It is important to consider race, ACE type, and life stage to gain a more sophisticated understanding of ACE-BMI relationships. This knowledge can help strengthen intervention, prevention, and policy efforts aiming to mitigate the impacts of social adversities and trauma on persistent cardiometabolic health disparities over the lifecourse.

Causal Effect of Relative Carbohydrate Intake on Hypertension through Psychological Well-Being and Adiposity: A Mendelian Randomization Study

Observations of the association between carbohydrate intake and hypertension are inconsistent, with mediating pathways unclear. We aimed to investigate the causal effect of relative carbohydrate intake on hypertension and the mediating roles of psychological well-being and adiposity. Using summary-level statistics of genome-wide association studies of European ancestry, we conducted univariable and multivariable Mendelian randomization (MR) to estimate the bidirectional causal association between relative carbohydrate intake (total energy-adjusted, mean: 42-51%) and hypertension (FinnGen: 42,857 cases/162,837 controls; UK Biobank: 77,723 cases/330,366 controls) and two-step MR to assess the mediating effects of psychological well-being indicators and adiposity traits on the association. MR estimates of hypertension from FinnGen and UK Biobank were meta-analyzed using the fixed-effect model given no heterogeneity. Meta-analyses of multivariable MR estimates from FinnGen and UK Biobank indicated that each one-SD higher relative carbohydrate intake was associated with 71% (odds ratio: 0.29; 95% confidence interval: 0.11-0.79) lower risk of hypertension, independently of other dietary macronutrients. Hypertension showed no reverse effect on carbohydrate intake. Five psychological well-being indicators and four adiposity traits causally mediated the association between relative carbohydrate intake and hypertension, including body mass index (mediation proportion: 51.37%), waist circumference (40.54%), waist-to-hip ratio (35.00%), hip circumference (24.77%), major depressive disorder (23.37%), positive affect (17.08%), depressive symptoms (16.52%), life satisfaction (16.05%), and neuroticism (11.22%). Higher relative carbohydrate intake was causally associated with lower hypertension risk, substantially mediated by better psychological well-being and less adiposity. Our findings inform causal targets and pathways for the prevention and intervention of hypertension.

Pseudohypoadrenalism, a subclinical cortisol metabolism disorder in hyperuricemia

Background

Hyperuricemia is a known risk factor of lipid metabolism disorder. However, the mechanisms have not been fully understood.

Methods

The serum samples from hyperuricemia subjects were used to analyze the correlation between serum uric acid and clinical characteristics. Hyperuricemia mice induced by potassium oxonate (PO) and adenine were used to explore glucocorticoid metabolism.

Results

In hyperuricemia patients, the levels of serum uric acid were positively correlated with the levels of γ-glutamyltransferase, associated with a cortisol metabolism disorder. In hyperuricemia state, the adrenal glands failed to respond to adrenocorticotropic hormone properly, leading to low cortisol, but not corticosterone production, and decreased mRNA levels of aldosterone synthase, 11β-hydroxylase, and 3β-hydroxysteroid dehydrogenase 1, three key enzymes for cortisol synthesis. The expression of both hepatic 5α-reductase and renal 11β-hydroxysteroid dehydrogenase 2 was significantly reduced, which led to low cortisol clearance. We denominated this cortisol metabolism disorder in hyperuricemia as pseudohypoadrenalism (PHAL).

Conclusion

PHAL increased exposure to the bioavailable cortisol in the liver, leading to local amplification of the biological action of corticosteroids. Unregulated biosynthesis pathway of bile acid expanded bile acid pool, and further aggravated cholestatic liver injury.

Multiple cardiometabolic diseases enhance the adverse effects of hypoalbuminemia on mortality among centenarians in China: a cohort study

BACKGROUND

Although hypoalbuminemia was associated with high risk of mortality in community-dwelling older adults, as well as in the hospitalized older adults, little is known among centenarians. And there are limited data on whether having cardiometabolic diseases (CMDs) is associated with additive effects.

METHODS

Baseline examinations including a determination of albumin levels were performed in 1002 Chinese centenarians from January 2014 through to December 2016, and the survival status was subsequently ascertained until 31 May 2021. Cox proportional risk model was performed to assess the risk of all-cause mortality associated with albumin levels and hypoalbuminemia combined with CMDs.

RESULTS

Of 1002 participants included in the analysis, the mean level of albumin was 38.5 g/L (± standard deviation, 4.0 g/L), and 174 (17.4%) had hypoalbuminemia (albumin < 35 g/L). The multivariable analyses showed that albumin level was negatively associated with all-cause mortality (Ptrend < 0.05). Compared to normoalbuminemia, hypoalbuminemia was associated with an increased mortality risk in the overall participants (hazard ratio [HR]: 1.55, 95% confidence interval [CI]: 1.22-1.97). Furthermore, the HR (95% CI) of hypoalbuminemia combined with multiple CMDs was 2.15 (1.14-4.07). There was evidence of an additive deleterious dose effect of an increasing number of CMDs (Ptrend = 0.001).

CONCLUSIONS

Hypoalbuminemia is associated with an increased risk of all-cause mortality in Chinese centenarians, and this risk is more pronounced among centenarians with multiple cardiometabolic diseases. Our findings suggest that older adults with hypoalbuminemia, especially comorbid multiple CMDs warrant early identification and management.

Plasma metabolite profiles associated with the World Cancer Research Fund/American Institute for Cancer Research lifestyle score and future risk of cardiovascular disease and type 2 diabetes

BACKGROUND

A healthy lifestyle (HL) has been inversely related to type 2 diabetes (T2D) and cardiovascular disease (CVD). However, few studies have identified a metabolite profile associated with HL. The present study aims to identify a metabolite profile of a HL score and assess its association with the incidence of T2D and CVD in individuals at high cardiovascular risk.

METHODS

In a subset of 1833 participants (age 55-80y) of the PREDIMED study, we estimated adherence to a HL using a composite score based on the 2018 Word Cancer Research Fund/American Institute for Cancer Research recommendations. Plasma metabolites were analyzed using LC-MS/MS methods at baseline (discovery sample) and 1-year of follow-up (validation sample). Cross-sectional associations between 385 known metabolites and the HL score were assessed using elastic net regression. A 10-cross-validation procedure was used, and correlation coefficients or AUC were assessed between the identified metabolite profiles and the self-reported HL score. We estimated the associations between the identified metabolite profiles and T2D and CVD using multivariable Cox regression models.

RESULTS

The metabolite profiles that identified HL as a dichotomous or continuous variable included 24 and 58 metabolites, respectively. These are amino acids or derivatives, lipids, and energy intermediates or xenobiotic compounds. After adjustment for potential confounders, baseline metabolite profiles were associated with a lower risk of T2D (hazard ratio [HR] and 95% confidence interval (CI): 0.54, 0.38-0.77 for dichotomous HL, and 0.22, 0.11-0.43 for continuous HL). Similar results were observed with CVD (HR, 95% CI: 0.59, 0.42-0.83 for dichotomous HF and HR, 95%CI: 0.58, 0.31-1.07 for continuous HL). The reduction in the risk of T2D and CVD was maintained or attenuated, respectively, for the 1-year metabolomic profile.

CONCLUSIONS

In an elderly population at high risk of CVD, a set of metabolites was selected as potential metabolites associated with the HL pattern predicting the risk of T2D and, to a lesser extent, CVD. These results support previous findings that some of these metabolites are inversely associated with the risk of T2D and CVD.

TRIAL REGISTRATION

The PREDIMED trial was registered at ISRCTN ( http://www.isrctn.com/ , ISRCTN35739639).

Imagine HEALTH: Changes in diurnal salivary cortisol patterns following a 12-week guided imagery RCT lifestyle intervention in predominantly Latino adolescents

OBJECTIVE

Alterations in diurnal salivary cortisol patterns have been linked to adverse metabolic health outcomes. We have previously shown that stress-reduction guided imagery (GI) can reduce salivary cortisol levels acutely. We now ask whether addition of GI into a 12-week lifestyle intervention designed to improve eating and physical activity behaviors can alter diurnal salivary cortisol patterns and perceived stress.

METHODS

232 adolescent participants (ages 14-17 years) were cluster randomized by school into one of four intervention arms: non-intervention Control (C; n = 51), Lifestyle (LS; n=61), Stress-Reduction GI (SRGI; n = 55), and Lifestyle Behavior GI (LBGI; n = 65). LS group received one nutrition and one physical activity class per week after-school for 12 weeks. SRGI and LBGI groups received same LS classes plus an additional weekly GI session. Salivary cortisol was assessed pre- and post-intervention on 3 days, 3 times daily, at awakening, 30-minutes post-awakening, and in the evening to determine Cortisol Awakening Response (CAR) and Diurnal Cortisol Slope (DCS). Perceived Stress Scale (PSS) was administered pre- and post-intervention. Mixed effects modeling was used for intent-to-treat analysis and sensitivity analysis was used for those participants adherent to intervention protocol.

RESULTS

Analysis of 208 subjects with complete data showed a small between-group increase in CAR in LBGI vs C (p = 0.045, d=0.24), with no significant group differences among other intervention arms. There were no between group differences in change in DCS or change in PSS after 12-weeks. Amongst adherent participants, LBGI showed a small-moderate increase in CAR (p = 0.03, d=0.37), and moderate-large reduction in PSS (p = 0.02, d=-0.66) compared to C. There were no other between group differences in CAR, DCS, or PSS.

CONCLUSION

LBGI led to an increase in CAR, and in adherent subjects, a decrease in PSS, suggesting GI may be a mind-body intervention that can affect both objective and subjective measures of the stress response. Whether changes in cortisol patterns in this population affect measures of mental or physical health remains to be determined.