Flatter Diurnal Cortisol Slopes Research Articles

The Interactive Effects of Rejection and Rumination on Diurnal Cortisol among Adolescent Girls: A Preliminary Daily Diary Study.

The perseverative cognition hypothesis stipulates that rumination (repetitive, passive, uncontrollable negative thinking) prolongs the experience of a stressor which impacts stress physiology. In line with this hypothesis, we proposed that in response to real-life experiences of social rejection, adolescent girls who ruminate would show a blunted diurnal cortisol slope the next day relative to girls who do not ruminate. We also examined the effects of social rejection and rumination on waking cortisol levels and the cortisol awakening response. Participants were (n = 50) adolescent girls (mean age = 13.30, SD = 2.34) who varied on psychiatric risk and provided saliva samples 4 times a day for 3 days, as well as, daily diary reports of social rejection and rumination. A lagged multilevel model was utilized to examine the interactive effects of rejection and rumination on diurnal cortisol. There was a significant interaction between social rejection and rumination. Specifically, rumination following social rejection was associated with a flatter diurnal cortisol slope. In the absence of rumination, social rejection was marginally associated with a steeper diurnal cortisol slope. The effects for waking cortisol levels and the cortisol awakening response were null. Findings support the perseverative cognition hypothesis and suggest that cognitive mechanisms such as rumination can impact stress physiology.

Diurnal cortisol profiles in autistic adolescents and young adults: Associations with social difficulties and internalizing mental health symptoms.

Several autism-related characteristics, such as social difficulties, may contribute to high perceived stress and increased exposure to stressful life events in some autistic individuals. Repeated exposure to stress might lead to the dysfunction of the hypothalamic-pituitary-adrenocortical-axis and be a vulnerability factor for developing mental health difficulties. Previous studies show contradictory findings on salivary cortisol in autism. In the current study, we investigated diurnal cortisol profiles in autistic adolescents and young adults, as well as their associations with social difficulties, stress exposure, and mental health symptoms. Autistic (n = 48, Mage = 17.6) and nonautistic (n = 51, Mage = 18.4) participants collected salivary cortisol at home six times a day for 2 days. Social difficulties, exposure to stressful life events/bullying, and mental health symptoms were assessed with questionnaires and clinical interviews. Similar diurnal cortisol slopes (DCS) and cortisol awakening responses were observed between the groups, but autistic participants showed higher total cortisol output (AUCG, area under the curve with respect to ground) during the day (b = 19.09, p = 0.009). In the autistic group, more severe social difficulties were associated with flatter DCS (b = 0.01, p = 0.007). Finally, cortisol alterations were associated with self-reported mental health symptoms, especially in autistic females in analyses uncorrected for multiple comparisons. In conclusion, our results do not indicate autism-related group-level alterations in most diurnal cortisol measures, but autistic youth showed higher total cortisol (AUCG) compared with nonautistic peers. More detailed investigation of interindividual variability in cortisol profiles within autistic people might give us important insights into vulnerability to developing stress-related mental health difficulties.

Daily associations between salivary cortisol and electroencephalographic-assessed sleep: a 15-day intensive longitudinal study.

Current evidence suggests that cortisol levels are bi-directionally associated with sleep. However, the daily, naturalistic cortisol-sleep associations remain unclear, as current evidence is mostly cross-sectional. This study tested whether pre-sleep cortisol predicts sleep duration and quality, and whether these sleep parameters predict the following day's diurnal cortisol slope using a 15-day intensive longitudinal design with electroencephalographic measures and saliva sampling. Ninety-five young adults (Mage = 20.48 ± 1.59 years) provided saliva samples at awakening and pre-sleep over 14 consecutive days, providing 2345 samples (85% viable). The Z-Machine Insight + was used to record over 900 nights of total sleep time (TST) and sleep efficiency (SE). Multilevel models tested these data at the between- and within-person levels. Higher pre-sleep cortisol predicted shorter TST (p < .001) and lower SE (p < .001) at the within-person level. Individuals with shorter average TST (p = .007) or lower average SE (p < .001) had flatter diurnal cortisol slopes, compared to those with longer average TST or higher average SE. Follow-up analyses showed that individuals with shorter average TST (vs. longer average TST) had higher pre-sleep cortisol levels (p = .01). Our findings provide evidence that pre-sleep cortisol is associated with sleep duration and quality at the within-individual level. Furthermore, individuals with short or poor sleep had flatter diurnal cortisol slopes. Although the effect sizes are small, these findings show the naturalistic associations between sleep and cortisol in a relatively healthy sample. These findings suggest that sleep maintains the regulation of the stress-response system, which is protective against mental and physical disorders.

Child biological stress and maternal caregiving style are associated with school readiness

Low socioeconomic status (SES) is a risk factor for unpreparedness for formal school entry. However, it is unclear how specific SES domains or factors related to SES, such as maternal caregiving style or child biological stress regulation, uniquely contribute to a child's academic competency. We examined the relation between early biological stress, SES, and caregiving style with the academic competency domain of school readiness in a preschool-age sample (N = 91) using multidimensional measures of SES, measures of maternal behavior, child hair cortisol concentrations, and diurnal salivary cortisol. We also investigated which correlates uniquely contribute to academic competency as indexed by the Bracken School Readiness Assessment and the NIH Picture Vocabulary Test. Higher cumulative biological stress, indexed through hair cortisol concentrations, was related to lower scores on both measures. Poor biological stress regulation, indexed by a flatter diurnal cortisol slope, was related to lower receptive vocabulary. More sensitive maternal behaviors and measures indicating higher SES were related to better performance in both academic competency measures. Of these significant associations, maternal intrusion and parental education uniquely contributed to pre-academic skills beyond other measures, whereas maternal structuring and parental education uniquely contributed to receptive vocabulary. These results provide new evidence that biological stress is related to academic competency in early childhood and demonstrate the importance of structured, non-intrusive parenting when preparing children for long-term academic success.

Relationship Between Cortisol Rhythm and Psychoneurological Symptom Cluster in Patients With Advanced Lung Cancer.

Patients with advanced lung cancer commonly experience a high prevalence of physical and psychological symptoms, which tend to co-occur as a symptom cluster. Cortisol rhythm has the potential to influence psychoneurological symptom cluster based on neuroendocrine-immune models; however, little is known about the relationship between them. To examine the intercorrelation among symptoms in psychoneurological symptom cluster and the factors influencing the severity of psychoneurological symptom cluster. One hundred sixty-one patients with advanced lung cancer were recruited from 2018 to 2020 as part of a large study. Data on sleep disturbances, fatigue, and psychological distress were collected via self-report questionnaires, and the diurnal cortisol slope was analyzed using saliva samples. Linear regression analyses were adopted to examine the association between cortisol rhythm and demographic and clinical variables with psychoneurological symptom cluster. Psychoneurological symptoms (including sleep disturbances, fatigue, anxiety, and depression) were significantly correlated. Poor physical performance status (β = -0.061, P < .001), increased number of comorbidities (β = 0.533, P < .001), and flatter cortisol rhythm (β = 545.092, P < .001) were significantly associated with higher-severity psychoneurological symptom cluster. Diurnal cortisol slope (β = 328.829, P = .025) was identified as the most critical factor influencing the psychoneurological symptom cluster in multiple linear regression model after adjusting for covariates. Patients with flatter diurnal cortisol slopes were found to experience more severe psychoneurological symptom cluster, after controlling for demographic and clinical factors. Interventions targeting the improvement of associated factors, such as comorbidities and physical performance status, could potentially alleviate the severity of the psychoneurological symptom cluster.

Increased Levels of Psychological Stress and Alterations in Stress Biology during Pregnancy among Women of Turkish-Origin in Germany

People of Turkish origin constitute one of the biggest migrant groups in Germany. They have an increased risk to develop stress-related health disadvantages, and this risk is also prevalent in the offspring generation from early ages on. We have conducted a multi-site prospective cohort study to examine the role of stress and stress biology in this intergenerational perpetuation of health disparities. 140 pregnant women (33 of Turkish origin) participated in a prospective cohort study with two study visits during pregnancy and one after birth (T1: 20-25 weeks of gestation, T2: 30-35 weeks of gestation, T3: four weeks after birth). At T1 and T2, women completed the Perceived Stress Scale and Center for Epidemiologic Studies Depression Scale and collected saliva samples after awakening, 30 minutes after awakening, and in the evening, and venous blood samples were collected for analysis of CRP and IL-6 concentrations. Multilevel models showed that Turkish-origin women exhibited higher levels of perceived stress and depressive symptoms, had increased inflammatory levels (Spallek et al., 2021), a blunted cortisol awakening response and flatter diurnal cortisol slope during pregnancy compared to non-migrant women after adjustment for socioeconomic factors.Some of the effects were mainly driven by 2nd generation migrants. Increased levels of psychosocial stress and stress-related biological alterations among Turkish-origin pregnant women may contribute to the intergenerational transmission of health disadvantages in this group.

Biological Embedding of Social Determinants of Health in Early Life and Across Generations

Population health disparities represent one of the most significant public health challenges. These disparities are evident from the earliest stages of life onwards, persist across the life span, are perpetuated across generations, and are strongly influenced by social and environmental factors. Chronic stress and stress-related biobehavioral processes are discussed as one of the major effectors of the causal pathways linking upstream social determinants with health and health disparities. It is evident that the effects of stress exposure can persist over long periods of time, even across the lifespan, and particularly so if exposure occurs during sensitive developmental windows such as the intrauterine period. In this symposium, presenters will address key questions and knowledge gaps regarding biological embedding of social disadvantage and the role of stress in this context, particularly during pregnancy and early life. Tom O’Connor will present data from the ECHO-UPSIDE cohort, a longitudinal pregnancy cohort study of a socio-economically and racially/ethnically diverse sample at elevated psychosocial risk but normal medical risk status. Results indicate that maternal pre-pregnancy adversity in early childhood is associated with prenatal behavioral and physical health markers, including depressive and anxiety symptoms, stress, body mass index (BMI), sleep disturbance, and diet, as well as maternal-fetal-placental biological markers that predict child health outcomes. Laura Scholaske will present results of a multi-site prospective pregnancy study conducted in Germany that includes people of Turkish origin that are among the biggest migrant groups in Germany. Results of the study suggest that pregnant women of Turkish origin exhibit higher psychological stress levels and alterations in stress-related biological systems (i.e., elevated inflammatory levels, blunted cortisol awakening response and flatter diurnal cortisol slope) compared to non-migrant pregnant women. Shannin N. Moody will address the effects of policing inequities that are one of the most harmful sources of systemic racism perpetuated against Black Americans. In three separate studies, she tested how unjust police encounter biologically “get under the skin” in Black youth from infancy to emerging adulthood. Rates of neighborhood stop-and-frisk were associated with shorter telomeres in infants. Children whose mothers experienced unfair treatment from police showed, during the TSST, blunted cortisol stress reactivity, slower cortisol recovery, and altered cortisol-testosterone coupling. Adolescents who experienced police encounters had higher waking cortisol as emerging adults. Taken together, the studies point so some of the potential pathways through which social determinants of health may propagate and transmit persisting health disparities. Elisabeth Shirtcliff will lead a discussion on the potential implications for early prevention and targeted intervention strategies to prevent or reverse biological embedding of social disadvantage in at risk individuals.

Additive, Common, and Cumulative Contributions of Stress on Diurnal Cortisol Activity: Evidence Among Latino College Students

The transition to college is a major socio-contextual shift marked by opportunity and stress. Adolescents who encounter significant stress during this time may experience changes in neuroendocrine function, an identified mechanism underlying associations between stress and psychopathology. Latino students may be particularly at-risk for stress exposure, as ethnic/racial minority youth experience both minority-specific and general life stressors. This study employed a “multi-risk model” to examine additive, common, and cumulative effects of various stressors on Latino college students’ diurnal cortisol. 180 Latino college students (Mage=18.95; 64.4% female) provided five saliva samples a day across three weekdays (M=14.88, SD=.95; 2,667 samples) to assess diurnal cortisol patterns (i.e., cortisol awakening response (CAR), diurnal cortisol slope (DCS)). Participants self-reported on multiple stress forms (general, academic, social, financial, bicultural, discrimination) via online survey and daily diary. Common and cumulative stress were assessed via exploratory factor analysis and cumulative risk index, respectively. Three-level growth curve models were fit using Mplus. In the additive model, general stress was associated with a flatter DCS (γ=.01, p=.03) and bicultural stress was linked with a steeper DCS (γ=-.07, p=.047). In the common model, college stress was related to a lower CAR (γ=-.09, p=.045). Higher cumulative stress was linked with a lower CAR (γ=-.06, p=.007). Findings highlight the physiological correlates of various stressors experienced by Latino college students. Results have implications for equity promoting interventions to reduce stress and subsequent physiological processes underlying the development of psychopathology.

Discrimination and Cortisol Dynamics among Older African Americans Adults

Discrimination has been found to predict self-report measures of general health as well as surrogate and clinical endpoints of various diseases. As the connection between discrimination and disease and pre-disease states became evident, research efforts started to include more investigations of the purported biological mediators. Dysregulation in the daily activity of the Hypothalamic-Pituitary-Adrenal (HPA) axis has been proposed as one of these mechanisms. The current study leverages data collected in the Health among Older Adults Living in Detroit project to investigate the relationship between three measures of discrimination (lifetime discrimination, habitual everyday discrimination, and daily everyday discrimination) and diurnal cortisol secretion in a sample of 203 older African Americans. Study results indicated that individuals reporting higher levels of lifetime discrimination experienced morning hypocortisolism and flatter diurnal cortisol slopes. Neither habitual (the estimated routine frequency of day-to-day experiences of unfair treatment) nor daily (the occurrence of discrimination experiences in a short and defined period – five days in our study) everyday discrimination were associated with cortisol secretion. However, exploratory analyses also showed that prior daily everyday discrimination was significantly associated with blunted cortisol awakening response (CAR) the next day. The link between lifetime discrimination and daily cortisol found in our study seems to support the stress accumulation model (stressors accumulate over time and have an additive effect on health processes and outcomes). Overall, our findings underline the role played by discrimination in modulating the activity of the HPA axis, whose regulation has critical implications for healthy aging.

Adverse Childhood Experiences Predict Diurnal Cortisol Throughout Gestation.

Adverse childhood experiences (ACEs) are associated with negative prenatal and perinatal health outcomes and may, via these pathways, have intergenerational effects on child health and development. We examine the impact of ACEs on maternal salivary cortisol, a key measure of prenatal biology previously linked with pregnancy-related health outcomes. Leveraging assessments across three trimesters, we used linear mixed-effects models to analyze the influence of ACEs on maternal prenatal diurnal cortisol patterns in a diverse cohort of pregnant women (analytic sample, n = 207). Covariates included comorbid prenatal depression, psychiatric medications, and sociodemographic factors. Maternal ACEs were significantly associated with flatter diurnal cortisol slopes (i.e., less steep decline), after adjusting for covariates, with effects consistent across gestation (estimate = 0.15, standard error = 0.06, p = .008). ACEs experienced before pregnancy may have a robust and lasting influence on maternal prenatal hypothalamic-pituitary-adrenal activity throughout gestation, a key biological marker associated with perinatal and child health outcomes. The findings suggest one route of intergenerational transmission of early adverse experiences and underscore the potential value of assessing prepregnancy adverse experiences for promoting perinatal and maternal and child health.

Lifetime discrimination, habitual and daily everyday discrimination, and diurnal cortisol among older African Americans adults

Experiences of discrimination can be major life events or daily chronic hassles that occur in various social contexts (e.g., housing, education, employment) and have been found to predict adverse health outcomes, including dysregulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis. Previous work on daily cortisol dynamics has generally revealed an association between discrimination and flatter cortisol slopes, particularly among racial minorities. However, most of the existing studies have focused on youth and young adults, with little work among older adults. The current study aimed to investigate the relationship between three measures of discrimination (lifetime discrimination, habitual everyday discrimination, and daily everyday discrimination) and diurnal cortisol secretion in a sample of 203 older African Americans. Study results indicated that individuals reporting higher levels of lifetime discrimination experienced morning hypocortisolism and flatter diurnal cortisol slopes. Exploratory analyses also showed that prior daily everyday discrimination was significantly associated with blunted cortisol awakening response (CAR) the next day. Our findings underline the role of discrimination in modulating daily cortisol dynamics among older African American adults and advance knowledge on how social stressors influence healthy aging.

Stress and diurnal cortisol among Latino/a college students: A multi-risk model approach.

The transition to college is a time of increased opportunity and stress spanning multiple domains. Adolescents who encounter significant stress during this transition may be vulnerable to adverse outcomes due to a "wear and tear" of the hypothalamic pituitary adrenal (HPA) axis. Latino/a students may be particularly at-risk for heightened stress exposure due to experiences of both minority-specific and general life stress. Despite this, little is known regarding the cumulative impact of multiple stressors on Latino/a students' HPA axis functioning. The present study employed a "multi-risk model" approach to examine additive, common, and cumulative effects of multiple stress forms (general, academic, social, financial, bicultural, ethnic/racial discrimination) on diurnal cortisol in a sample of first-year Latino/a college students (N = 196; 64.4% female; Mage = 18.95). Results indicated that no stress forms were additively associated with the cortisol awakening response (CAR), but general stress was associated with a flatter diurnal cortisol slope (DCS) and bicultural stress was linked with a steeper DCS. A college stress latent factor was associated with a lower CAR, whereas a latent factor of discrimination was not associated with diurnal cortisol. Cumulative risk was linked with a lower CAR. Findings highlight the physiological correlates of various stressors experienced by Latino/a college students.

Elevated stress during pregnancy in women of Turkish origin: Results from a prospective cohort study

Abstract Background Ethnic health disparities exist in the context of pregnancy and childbirth, suggesting that women of Turkish origin (i.e., they or their parents born in Turkey) in Germany have higher risks for some adverse maternal health and child developmental outcomes. Stress is believed to be a relevant pathway by which migration may be associated with these risks. In this study, we tested associations of Turkish origin with stress biology and psychological stress experiences during pregnancy. Methods 140 pregnant women (33 of Turkish/26 of other origin) participated in a prospective cohort study that was carried out in Bielefeld and Berlin (Spallek et al., 2020). Inflammatory markers CRP and IL-6 from venous blood samples and diurnal cortisol profiles from salivary cortisol samples were derived and participants completed the Perceived Stress Scale (PSS) and Center for Epidemiologic Studies Depression Scale (CESD) at two study visits during pregnancy (T1: 20-25 weeks of gestation, T2: 30-35 weeks of gestation). Multilevel models were conducted to account for the nested data structure due to repeated measurements. Results Compared to non-migrant women, women of Turkish origin had significantly higher inflammatory levels (b = 0.28, SE = 0.14, p=.052) (Spallek et al., 2021), a blunted cortisol awakening response (b=-0.21, CI=-0.38–0.03, p&amp;lt;.05), a flatter diurnal cortisol slope (b = 0.02, CI = 0.00-0.04, p&amp;lt;.05), and higher PSS (b = 0.46, SE = 0.13, p&amp;lt; .001) and CESD scores (b = 0.29, SE = 0.08, p&amp;lt;.001) during pregnancy after adjusting for socioeconomic factors. Conclusions The results of our study suggest higher stress at the biological and psychological level in pregnant women of Turkish origin. Stress is a risk factor for pregnancy complications and poor birth and child developmental outcomes. To reduce such unequally distributed risks, interventions for stress reduction are needed that are tailored to women of Turkish origin. Key messages • Women of Turkish origin in Germany have elevated psychological and biological stress levels during pregnancy compared to non-migrant women. • This finding underscores the need for targeted interventions to reduce stress in this high-risk group.

Diurnal cortisol variation during pregnancy in Turkish origin and non-migrant women in a German birth cohort study

BackgroundImmigrants from Turkey experience health disadvantages relative to non-immigrant populations in Germany that are manifest from the earliest stages of the lifespan onwards and are perpetuated across generations. Chronic stress and perturbations of stress-responsive physiological systems, including the hypothalamus-pituitary-adrenal (HPA)-axis, are believed to in part mediate this relationship. Cortisol plays an important role in the association between maternal stress during pregnancy and many pregnancy-, birth- and offspring-related outcomes. We therefore examined whether maternal migrant background is associated with diurnal cortisol variation during pregnancy. Methods109 pregnant women (incl. n = 32 Turkish origin women) that participated in a multi-site prospective cohort study in Germany collected saliva samples across the day on two consecutive days around 24 and 32 weeks gestation. Hierarchical linear models were applied to quantify associations between migrant background and diurnal cortisol variation across pregnancy. ResultsWomen of Turkish origin exhibited a significantly lower cortisol awakening response (CAR) and a flatter diurnal cortisol slope (DCS) compared to non-migrant women after adjusting for household income. These relationships between migrant status and diurnal cortisol variation were mainly driven by 2nd generation migrants. DiscussionA potential HPA axis dysregulation of Turkish-origin pregnant women may contribute to the intergenerational transmission of health disadvantages in this group.

Biological sensitivity to environmental context fluctuates dynamically within individuals from day to day

This longitudinal, within-subjects study examined whether adolescents’ biological sensitivity to socioeconomic status (SES) for emerging social difficulties varied day to day. Diverse adolescents (N = 315; ages 11–18; 57% female; 25% Asian, 18% Latinx, 11% Black) provided daily diaries and saliva samples for 4 days. We measured biological sensitivity as daily fluctuations in diurnal cortisol slope, and SES as a principal component of family income and maternal education. A robust analysis of 1013 daily assessments revealed that youth from lower SES homes reported greater social difficulties only on days that they exhibited flatter diurnal cortisol slopes, and youth from higher SES homes reported fewer social difficulties on these days. SES was not associated with social difficulties on days that adolescents exhibited steeper, declining diurnal cortisol slopes. Findings support recent theory that risk and resilience are dynamic processes that change within individuals over time. For better and for worse, youth may be more biologically sensitive to their family socioeconomic environments on days that their diurnal cortisol rhythms are flattened.

Adverse childhood experiences and diurnal cortisol patterns in older people in England

Adverse childhood experiences (ACE) are associated with HPA axis dysregulation at younger ages, but there is scarcity of evidence for this association at older ages. To add to our knowledge of the lifetime impact of ACE on HPA axis function, we examined whether ACE were associated with diurnal cortisol patterns in a national sample of 587 participants (356 women) aged 55–79 years from the English Longitudinal Study of Ageing (ELSA). We conducted descriptive analyses and estimated sex-specific robust regression models of the associations between the 8-item summary ACE score and four measurements of salivary cortisol over a 24-h cycle (upon waking, 30 min later, at 7 pm, and at bedtime) as well as the cortisol awakening response (CAR) and the diurnal cortisol slope. Our models were adjusted for age, then for childhood socioeconomic position and finally for adult socioeconomic position. In men, we found significant differences that were independent of covariates, with more ACE being associated with lower salivary cortisol levels on waking, a greater CAR, and a flatter diurnal cortisol slope. In women, we observed a graded association between ACE and increased 7 pm salivary cortisol levels. Our findings indicate that childhood adversity is related to HPA axis in older people, especially men. The chronological distance (on average >50 years) between ACE and salivary cortisol levels suggests the existence of a lifelong association between childhood adversity and HPA axis and neuroendocrine function. Notwithstanding sex differences, based on our findings we suggest that HPA axis dysregulation could be a pathway that mediates the association between ACE and chronic disease later in life.

Relationships Between Salivary Cortisol Slope and Neuropsychiatric Symptoms in Persons Living With Dementia

While a flatter diurnal cortisol slope has been related to poor health outcomes in healthy populations, little is known about this relationship in persons living with dementia (PLWD). The purpose of this study was to examine the association between diurnalcortisol slope and neuropsychiatric symptoms in PLWD. Secondary data analysis was conducted using baseline data from the Healthy Patterns Study (N=168). Diurnal cortisol slope was calculated using the difference between changes in salivary cortisol from 30 minutes after awakening to bedtime. Spearman rho coefficients were used. Flatter cortisol slope was associated with the presence of symptoms of agitation (r=-0.191, p=0.013) and disinhibition (r=-0.168, p=0.03). Steeper cortisol slope was related to a more severe level of anxiety symptoms (r=0.36, p=0.009) and higher frequency of insomnia (r=0.292, p=0.011). We found that cortisol slope was associated with neuropsychiatric symptoms in PLWD. Future research is needed to examine the mechanisms underlying the relationships.

Diurnal Cortisol Slope and Nighttime Blood Pressure: A Study in European Americans and African Americans.

African Americans (AAs) have higher nighttime blood pressure (BP) than European Americans (EAs). Stress has been suggested to play a role in this difference, but the mechanism is not well-understood. Flatter diurnal cortisol slope (DCS) is a well-known biological marker of stress. The objectives of this study were to: 1) examine ethnic differences in DCS; 2) evaluate the association between DCS and nighttime BP; and 3) determine the extent to which ethnic differences in nighttime BP can be explained by ethnic differences in DCS. A total of 510 participants (age range: 14-35 years; 49.6% AAs, 54.5% females) provided four salivary cortisol samples at bedtime, wakeup, 30-minutes post-wakeup, and 60-minutes post-wakeup. Additionally, participants wore an ambulatory BP monitor for 24 hours. DCS was calculated as the average of the three morning samples minus the bedtime measurement. After adjustment for age, sex, BMI, and smoking, AAs had blunted DCS (P=.018) and higher nighttime systolic BP (SBP) and diastolic BP (DBP) (Ps<.001) compared with EAs. The DCS was inversely related to nighttime SBP and this relationship did not depend on ethnicity. The ethnic difference of nighttime SBP was significantly attenuated upon addition of DCS to the model. Mediation test showed that 9.5% of ethnic difference in nighttime SBP could be explained by DCS (P=.039). This study confirms ethnic differences in DCS and nighttime BP and further demonstrates that the ethnic differences in DCS can, at least partially, explain the ethnic differences found in nighttime BP.

Cortisol dysregulation among American Sign Language interpreters in different work settings: Confirmation of occupational health risks

Cumulative motion injuries and burnout contribute to an international shortage of signed language interpreters (SLIs). Studies using the Job Content Questionnaire, a well-validated measure of occupational health risks, indicate that risk levels differ among SLI work settings. Specifically, video relay service (VRS) and primary and secondary educational settings (K–12) are associated with greater health risks. The current study validated those results by analysing the diurnal rhythm of salivary cortisol levels. Anomalies in diurnal cortisol rhythms are associated with an array of health problems. Our full-time SLI participants included VRS workers ( N = 20), K–12 workers ( N = 18), and SLIs who worked in other settings ( N = 23). Non-interpreters using sign language daily at work ( N = 18) comprised a fourth group. Saliva samples were collected four times daily over 2 working days. The VRS and K–12 SLIs demonstrated lower morning peak cortisol levels and flatter diurnal cortisol slopes from morning peak to subsequent diminution. Both findings are associated with chronic stress and greater health risks. The VRS and K–12 groups’ diurnal cortisol patterns closely resembled each other, while the Other SLI group’s curve closely resembled that of the Non-Interpreter group. Implications for SLI health, education, and job redesign are discussed in the context of the demand control schema.

Chronic Inflammation Mediates the Association between Cortisol and Hyperglycemia: Findings from the Cross-Sectional Population-Based KORA Age Study.

(1) Background: The study aimed to investigate the role of subclinical inflammation on the association between diurnal cortisol patterns and glycaemia in an aged population. (2) Methods: Salivary cortisol, interleukin-6 (IL-6) and glycated haemoglobin (HbA1c) were analysed in a sample of 394 men and 364 women (mean age = 5 ± 6.3, 65–90 years). The ratio of morning after awakening and late-night cortisol was calculated as an indication of diurnal cortisol slope (DCS). Multivariable regression models were run to examine whether IL-6 mediates the relationship between the DCS and glycaemia. The Sobel test and bootstrapping methods were used to quantify the mediation analyses. (3) Results: In comparison to normoglycaemic counterparts (n = 676, 89.2%), an increase in IL-6 concentrations, in individuals with hyperglycaemia (HbA1c ≥ 6.5%) (n = 82, 10.8%) (p = 0.04), was significantly associated with a flatter DCS. The link between flatter DCS and elevated HbA1c level was significant mediated by a heightened IL-6 level. Our results do not suggest reverse-directionality, whereby cortisol did not mediate the association of IL-6 with HbA1c. (4) Conclusions: In our sample, the relation between flatter DCS and hyperglycaemia was partly explained by IL-6 levels. The paradigm of subclinical inflammation-mediated cortisol response on glucose metabolism could have widespread implications for improving our understanding of the pathophysiology of type 2 diabetes mellitus.