Diurnal Cortisol Output Research Articles

Sex-related differences in the associations between diurnal cortisol pattern and social and emotional loneliness in older adults.

Loneliness is a distressful feeling that can affect mental and physical health, particularly among older adults. Cortisol, the primary hormone of the Hypothalamic-Pituitary-Adrenal axis (HPA-axis), may act as a biological transducer through which loneliness affects health. While most previous studies have evaluated the association between loneliness, as a unidimensional construct, and diurnal cortisol pattern, no research has examined this relationship discriminating between social and emotional loneliness in older adults. As sex differences in the negative mental health outcomes of loneliness have been reported, we also investigated whether diurnal cortisol indices and loneliness associations occur in a sex-specific manner. We analyzed the diurnal cortisol- pattern in 142 community-dwelling, non-depressed, Caucasian older adults (55,6% female) aged 60-90. Social and emotional (family and romantic) loneliness scores were assessed using the Spanish version of the Social and Emotional Loneliness Scale for Adults (SELSA). Five salivary cortisol samples were used to capture key features of the diurnal cortisol pattern, including: awakening and bedtime cortisol levels, awakening response (CAR), post-awakening cortisol output (post-awakening cortisol [i.e., the area under the curve with reference to the ground: AUCG]), total diurnal cortisol release (AUCG), and diurnal cortisol slope (DCS). After controlling for sociodemographic variables, the hierarchical linear multiple regression analyses revealed that in male older adults, higher scores on social and family loneliness were associated with elevated awakening cortisol levels, total diurnal cortisol output, and a steeper diurnal cortisol slope (DCS). However, these associations were not observed in female older adults. In addition, feelings of romantic loneliness were positively associated with bedtime cortisol levels and AUCG in older males. Multilevel growth curve modeling showed that experiencing more social and emotional loneliness predicted higher diurnal cortisol output throughout the day in older male adults. The presence of sex differences in the relationship between cortisol indices and loneliness among older adults holds particular significance for diagnostic and screening procedures. Combining loneliness scales as screening tools with diurnal cortisol measures has the potential to be an effective and cost-efficient approach in identifying higher-risk individuals at early stages.

The influence of intensive care treatment in infancy on cortisol levels in childhood and adolescence

BackgroundInfants admitted to the intensive care unit experience numerous early-life stressors, which may have long-term effects on hypothalamic-pituitary-adrenal axis functioning. AimsTo determine the effects of intensive care treatment and related exposure to stress, pain, and opioids in infancy on cortisol levels in childhood and adolescence. Study designCross-sectional study. SubjectsChildren and adolescents aged 8 to 18 years with a history of intensive care treatment in infancy and healthy controls. The intensive care treatment cohort consisted of four subgroups with varying levels of exposure to stress, pain, and opioids in infancy. They received either mechanical ventilation, extracorporeal membrane oxygenation, major surgery, or excochleation of a giant congenital melanocytic nevus. Outcome measuresBetween-group differences in stress reactivity to a study visit consisting of pain threshold testing and an MRI examination and diurnal cortisol levels, as measured in saliva. ResultsAfter adjustment for age, sex, and gestational age, the diurnal cortisol output (AUCg) in the overall intensive care group (N = 76) was 18 % (approximately 1000 nmol/L) (95 % CI [−31 %, −3 %], P = 0.022) lower than that in the control group (N = 67). Cortisol awakening response, diurnal decline, and stress reactivity neither differed significantly between the overall intensive care group and control group, nor between the intensive care subgroups and control group. ConclusionChildren and adolescents with a history of intensive care treatment in infancy have similar cortisol profiles to those of healthy controls, except for an 18 % lower diurnal cortisol output. The clinical relevance of this reduction is yet to be determined.

ADHD symptoms and diurnal cortisol in adolescents: The importance of comorbidities

BackgroundAltered regulation of diurnal cortisol has been associated with both dimensional symptoms and clinical diagnoses of attention deficit-hyperactivity disorder (ADHD). Indeed, a recent meta-analysis suggests that lower diurnal cortisol output may be a biomarker of attention deficit-hyperactivity disorder (ADHD); importantly, however, the influence of psychiatric comorbidities on this association has not been characterized. Approximately two-thirds of children with ADHD have at least one co-occurring neuropsychiatric condition, and altered HPA-axis function has been implicated in many of these conditions. Using dimensional measures of psychopathology, we examined whether comorbid symptoms influence the association of ADHD symptoms with daily cortisol output. Methods138 adolescents (ages 11–15 years) completed measures of symptoms of psychopathology and provided saliva samples over two days. We analyzed whether ADHD symptoms were related to morning, afternoon, and evening cortisol, the cortisol awakening response (CAR) and cumulative daily cortisol (area under the curve with respect to ground [AUCg]) while accounting for symptoms of three psychiatric disorders that are commonly comorbid with ADHD: conduct disorder (CD), anxiety, and depression. In sensitivity analyses, we included symptoms of oppositional defiant disorder (ODD) in place of CD symptoms. FindingsAfter controlling for symptoms of CD, anxiety, and depression, ADHD symptoms were associated significantly with higher cumulative diurnal cortisol (AUCg), morning cortisol, and afternoon cortisol. Symptoms of CD, anxiety and depression were not associated significantly with any cortisol metrics; however, in sensitivity analyses, ODD symptoms were associated with lower AUCg and morning cortisol. DiscussionOur findings highlight the distinct influence of ADHD and externalizing symptoms on cortisol output. Further work is needed to examine the specificity of altered HPA-axis activity as a biomarker of ADHD and to elucidate whether symptoms of ADHD differ in their association with diurnal cortisol as a function of their severity.

Pre-pandemic Psychobiological Features Predict Impact of COVID-19 Confinement on Loneliness.

The coronavirus disease 2019 (COVID-19) pandemic led to various government-imposed limitations on social interaction and strict home confinement. Such involuntary social-distancing policies can exacerbate feelings of loneliness and alter emotional well-being. Dysregulation of the hypothalamic-pituitary-adrenocortical (HPA) axis is a potential mechanism for loneliness’ deleterious health effects. In this study, we explored whether pre-pandemic diurnal cortisol output (AUCG), a measure of HPA axis function, may predict the propensity to changes in loneliness during long-term COVID-19 home confinement and if extraversion would moderate this relationship. This association has been explored by analysing the impact of COVID-19 pandemic and strict home confinement on social and emotional loneliness in 45 Spanish young adults. Diurnal cortisol levels were measured from five saliva samples obtained across a day just before the pandemic, and data about participants’ perceived loneliness, empathic state, extraversion, and prospective volunteering were obtained both before and during the confinement. Participants’ social and family loneliness increased during long-term strict home confinement, while prospective volunteering tendencies and extraversion decreased. Importantly, after adjusting for relevant confounders, moderation analyses revealed that in young adults with high pre-pandemic extraversion, a higher AUCG predicted a larger increase in social loneliness during confinement, while in individuals with low extraversion, AUCG was negatively related to change in loneliness. Our findings highlight the utility of pre-pandemic diurnal cortisol output in predicting the social impact of COVID-19 home confinement, presenting this hormone as a potential biomarker for a priori identification of at-risk groups during public health crises.

Adrenocortical responses of emerging adults in California in the two months following the Pulse night club massacre: Evidence for distal stress responses

This study examined adrenocortical responses in the days following the Pulse nightclub massacre on June 12, 2016, among emerging adults in Northern California (N = 202; M = 23.18 years, SD = 2.56; 25% LGBQ-Latinx, 25% LGBQ-White, 25% Straight-Latinx, and 25% Straight-White) between June 13—August 12, 2016. As predicted, participants tested more proximally to the massacre had higher waking cortisol (intercepts) and flatter diurnal cortisol output (slopes), indicative of time-dependent adrenocortical arousal across the day. The effect of days post-massacre on waking cortisol was moderated by daily distress, with days since the Pulse massacre predicting waking cortisol significant only for participants reporting lower distress; participants who reported feeling higher daily distress had elevated waking cortisol across the testing period. These findings were independent of weekly personal stressors, and consistent across participants’ demographic and identity characteristics. The violent attack at the Pulse nightclub was connected to increased waking cortisol and diurnal cortisol production for several days after the massacre, in a distal population exposed to the massacre vicariously, and especially for individuals not experiencing other, personal stressors. Heightened physiological responses to violent crimes support policy efforts to protect vulnerable communities, including violence prevention, gun control, and community-based trauma response services for those directly and indirectly affected by gun violence.

Children's diurnal cortisol output and temperament in two different childcare settings at 2 and 3.5 years of age.

Prior research suggests that child temperament may play an important role in early childhood stress regulation. We compared children's diurnal cortisol and the association between cortisol and temperament in two different childcare settings. Cortisol was measured from saliva samples over 2 days in children (N=84) attending out-of-home childcare and in children (N=27), who were cared for at home at the age of 3.5 years. There was no difference between the childcare groups in total diurnal cortisol. However, of the individual measurements, afternoon cortisol levels were higher in the out-of-home childcare group during their childcare day when compared with their home day. Child temperament was not associated with total diurnal cortisol. Comparison with our prior measurements showed that the association between temperamental surgency/extroversion and total diurnal cortisol diminished along with the child age from 2 to 3.5 years in both childcare settings. This may indicate that more extroverted children are physiologically more reactive to environmental stimuli when they are younger, but this association does not appear as the children develop. Our results further suggest that the afternoon hours in the out-of-home childcare may be demanding and accelerate the hypothalamus-pituitary-adrenal axis activation in young children independent of their age.

Childhood maltreatment disrupts HPA-axis activity under basal and stress conditions in a dose-response relationship in children and adolescents.

This study investigates the impact of childhood maltreatment (CM) on hypothalamic-pituitary-adrenal (HPA)-axis functioning and on anxiety perception. Moreover, the influence of CM severity and frequency was also explored. In total, 187 participants aged 7-17 were assessed for CM history using validated questionnaires and ad hoc interviews to be classified according to the criteria of the Tool for Assessing the Severity of Situations in which Children are Vulnerable (TASSCV). Psychopathology was ascertained using the K-SADS-PL5. To assess HPA-axis functioning, salivary cortisol samples were collected throughout a normal day and during an acute psychosocial stressor, the Trier Social Stress Test for children (TSST-C). Subjective anxiety was evaluated using STAI/-C. Youth with a CM history had higher overall diurnal cortisol levels (p = 0.001), blunted cortisol response to acute psychosocial stress (p = 0.002) and greater perceived anxiety (p = 0.003), than those without CM. Specifically, participants exposed to moderate/severe or often/frequent CM showed the greater diurnal cortisol output (pseverity = 0.002; pfrequency = 0.003), and blunted cortisol response during the TSST-C (pseverity = 0.006; pfrequency = 0.008). Meanwhile, youth with low CM severity/frequency exhibited a similar cortisol response to those without CM. However, perceived anxiety was higher in those exposed to CM (p < 0.001), regardless of its severity/frequency. Disturbances in HPA-axis functioning are already evident early after CM exposure, while psychological and physiological responses to an acute stressor are dissociated in youth exposed to CM. The dose-response relationship described in this paper highlights the need to comprehensively evaluate CM so that vulnerable children can be identified and assigned to proper interventions.

Associations between social burden, perceived stress, and diurnal cortisol profiles in older adults: implications for cognitive aging

Stress can be a risk factor for mental and physical health. We investigated the role of social burden as a potential stressor in older age and its associations with cognitive aging (i.e., within the domains inhibition and cognitive flexibility of executive functioning). Eighty-three older adults (N = 38 male, mean age = 74.0 ± 5.7 years, body-mass index = 25.5 ± 4.1 kg/m2) aged 64 years or older participated. Cognitive flexibility and inhibition were assessed by means of a Trail-Making Test (TMT) and a Stroop task. Perceived levels of social burden and perceived stress in general were assessed via standardized questionnaires. Furthermore, diurnal cortisol profiles were assessed. Overall, older participants showed lower cognitive performance than the younger (both inhibition and cognitive flexibility; p < .044). However, this association did not remain significant when adjusting for multiple comparisons. Social burden was highly correlated with perceived stress, highlighting its importance as a stressor (p < .001). Furthermore, participants who reported higher levels of perceived stress showed lower performance in the TMT as a measure for cognitive flexibility (p < .001). Moreover, social burden was associated with cognitive flexibility, which was assessed by means of the TMT (p = .031). However, this association did not remain significant when using the adjusted α-level. Furthermore, we found that total diurnal cortisol output was a mediator for the relationship between age and inhibition, which was assessed by means of a Stroop task. At last, we found that the mediating role of cortisol interacts with social burden in the way that especially in younger age, high levels of social burden are associated with higher cortisol levels and, therefore, with lower cognitive performance. We conclude that it is important to consider social burden as an additional stressor in older age which is associated with cognitive aging.

Diabetes-related distress and daily cortisol output in people with Type 2 diabetes

AimsDiabetes-related distress is common in Type 2 Diabetes and is linked with poor diabetes control. However, mechanisms underlying this association are unclear. One pathway that could be involved is neuroendocrine dysfunction, as Type 2 Diabetes is associated with altered diurnal cortisol output. This study investigated the link between diabetes-related distress and diurnal cortisol output. Methods134 people with Type 2 Diabetes provided 5 cortisol samples over the course of a day. Multivariate linear regression models were used to assess whether overall and sub-domains of diabetes-related distress measured by the Diabetes Distress Scale, predicted cortisol parameters (waking cortisol, cortisol awakening response, cortisol slope and evening cortisol). ResultsPhysician-related distress was associated with greater waking (B = 2.747, p = .015) and evening cortisol (B = 1.375, p = .014), and a blunted cortisol awakening response (B = −3.472, p = .038) adjusting for age, sex, income, body mass index, smoking and time of awakening. No associations were detected for overall distress, emotional, interpersonal or regimen distress. ConclusionPhysician-related distress was associated with alterations in daily cortisol output. Longitudinal research is required to understand how physician-related distress is associated with diurnal cortisol patterning over time.

Weak and uneven associations of home, neighborhood, and school environments with stress hormone output across multiple timescales.

The progression of lifelong trajectories of socioeconomic inequalities in health and mortality begins in childhood. Dysregulation in cortisol, a stress hormone that is the primary output of the hypothalamus-pituitary-adrenal (HPA) axis, has been hypothesized to be a mechanism for how early environmental adversity compromises health. However, despite the popularity of cortisol as a biomarker for stress and adversity, little is known about whether cortisol output differs in children being raised in socioeconomically disadvantaged environments. Here, we show that there are few differences between advantaged and disadvantaged children in their cortisol output. In 8-14-year-old children from the population-based Texas Twin Project, we measured cortisol output at three different timescales: (a) diurnal fluctuation in salivary cortisol (n = 400), (b) salivary cortisol reactivity and recovery after exposure to the Trier Social Stress Test (n = 444), and (c) cortisol concentration in hair (n = 1210). These measures converged on two moderately correlated, yet distinguishable, dimensions of HPA function. We tested differences in cortisol output across nine aspects of social disadvantage at the home (e.g., family socioeconomic status), school (e.g., average levels of academic achievement), and neighborhood (e.g., concentrated poverty). Children living in neighborhoods with higher concentrated poverty had higher diurnal cortisol output, as measured in saliva; otherwise, child cortisol output was unrelated to any other aspect of social disadvantage. Overall, we find limited support for alteration in HPA axis functioning as a general mechanism for the health consequences of socioeconomic inequality in childhood.

The relationship between sleep problems and cortisol in people with type 2 diabetes

BackgroundSleep problems are linked with negative health outcomes, including coronary heart disease. Neuroendocrine dysfunction has been associated with sleep problems and may be a pathway linking sleep and ill health. Dysregulated cortisol output has observed in people with type 2 diabetes (T2D), though little is known about the links between sleep and cortisol in this population at high risk of coronary disease. MethodThis study investigated the association between sleep problems and cortisol over the course of an ordinary day and in response to acute laboratory stress in a sample of 129 individuals with T2D. Sleep problems were assessed using the Jenkins sleep problems questionnaire. Mental stress was induced using two five-minute laboratory stress tasks: a mirror-tracing task and the Stroop color-word interference task. ResultsSleep problems were positively associated with daily cortisol area under the curve (B = 17.051, C.I. = 6.547 to 27.554, p = 0.002) adjusting for age, sex, marital status, education, household income, body mass index and smoking; suggesting that those with greater sleep problems had greater cortisol concentrations over the course of an ordinary day. Participants reporting greater sleep problems also had raised evening cortisol levels (B = 0.96, C.I. = 0.176 to 1.746, p = 0.017) in adjusted models. In the laboratory sleep problems were negatively associated with cortisol immediately post-task (B = -0.030, C.I. = -0.059 to 0.000, p = 0.048) and 45 minutes post-task (B = -0.037, C.I. = -0.072 to -0.002, p = 0.039) in fully adjusted models; indicating that those who experienced greater sleep problems had lower cortisol concentrations after stress. ConclusionsSleep problems were associated with disturbances in cortisol responses to stress, as well as changes diurnal cortisol output in people with T2D. Further research is needed to assess if neuroendocrine disturbance increases the risk of cardiovascular disease in this population.

Ethnic differences in diurnal cortisol profiles in healthy adults: A meta-analysis.

Cortisol is a well-known biomarker of the physiological stress system; atypical cortisol patterns have been linked to many psychological and physiological illnesses. Previous studies have found vast health disparities among ethnic groups; however, studies examining the relationship between cortisol and ethnicity have found mixed results. This meta-analysis investigated whether there are differences in diurnal cortisol outcomes among ethnic groups, while considering the moderating roles of various individual factors and methodological approaches. Search phrases were entered into MEDLINE, PsycINFO, EMBASE, Cochrane Library, CINAHL, Scopus, and Web of Science. Effect sizes were extracted for ten diurnal cortisol outcomes, including waking, 30min after waking, cortisol awakening response, slope, area under the curve, urinary twenty-four-hour secretion, total cortisol output, and midday, evening, and bedtime concentrations, for eight ethnic group comparisons, including Asians, Blacks, Hispanics, Indigenous people, Whites, Minority and Majority groups, and Multiethnic groups. Moderator analyses, including variables such as gender, age, and number of cortisol collection time points, were conducted. There were significant ethnic differences in diurnal cortisol profiles, including cortisol awakening responses, with more robust differences in ethnic comparisons that included White participants. Differences in diurnal cortisol profiles were also moderated by gender, mean age, and sample size. This meta-analysis supports the notion that ethnic groups exhibit distinct diurnal cortisol profiles, which, according to the biopsychosocial model of health, may be a result of unique sociocultural experiences. The limitations of this meta-analysis and future directions for stress research with various ethnic groups are discussed. Statement of contribution What is already known on this subject? Studies have found vast health disparities among ethnic groups. Psychological and physiological illnesses and atypical diurnal cortisol profiles are strongly correlated. Studies have examined the relationship between diurnal cortisol rhythms and ethnicity, but findings are mixed. What does this study add? This study is a systematic examination of the relationship between diurnal cortisol rhythm and ethnicity. Psychosocial and methodological factors moderate the relationship between diurnal cortisol output and ethnicity. This study provides insight on factors that contribute to health disparities among ethnic groups.

Racial/ethnic disparities in cortisol diurnal patterns and affect in adolescence.

Racial/ethnic minorities are more vulnerable to mental and physical health problems, but we know little about the psychobiological underpinnings of these disparities. In this study, we examined racial/ethnic differences in cortisol diurnal patterns and affect as initial steps toward elucidating long-term health disparities. A racially/ethnically diverse (39.5% White, 60.5% minority) sample of 370 adolescents (57.3% female) between the ages of 11.9 and 18 years (M = 14.65 years, SD = 1.39) participated in this study. These adolescents provided 16 cortisol samples (4 samples per day across 4 days), allowing the computation of diurnal cortisol slopes, the cortisol awakening response, and diurnal cortisol output (area under the curve), as well as daily diary ratings of high-arousal and low-arousal positive and negative affect. Consistent with prior research, we found that racial/ethnic minorities (particularly African American and Latino youth) exhibited flatter diurnal cortisol slopes compared to White youth, F (1, 344.7) = 5.26, p = .02, effect size g = 0.25. Furthermore, African American and Asian American youth reported lower levels of positive affect (both high arousal and low arousal) compared to White youth. Racial/ethnic differences in affect did not explain differences in cortisol patterns, suggesting a need to refine our models of relations between affect and hypothalamic-pituitary-adrenocortical activity. We conclude by proposing that a deeper understanding of cultural development may help elucidate the complex associations between affect and hypothalamic-pituitary-adrenocortical functioning and how they explain racial/ethnic differences in both affect and stress biology.

Cortisol relates to regional limbic system structure in older but not younger adults

We investigated if the relationship between age and regional limbic system brain structure would be moderated by diurnal cortisol output and diurnal cortisol slope. Participants aged 23–83 years collected seven salivary cortisol samples each day for 10 consecutive days and underwent magnetic resonance imaging. Age, sex, cortisol, and an age x cortisol interaction were tested as predictors of hippocampal and amygdalar volume and caudal and rostral anterior cingulate cortex (ACC) thickness. We found significant interactions between age and cortisol on left and right amygdalar volumes and right caudal ACC thickness. Older adults with higher cortisol output had smaller left and right amygdalar volumes than older adults with lower cortisol output and younger adults with higher cortisol output. Older and younger adults with lower cortisol output had similar amygdalar volumes. Older adults with a steeper decline in diurnal cortisol had a thicker right caudal ACC than younger adults with a similarly shaped cortisol slope. Hippocampal volume was not related to either cortisol slope or output, nor was pallidum volume which was assessed as an extra-limbic control region. Results suggest that subtle differences in cortisol output are related to differences in limbic system structure in older but not younger adults.

Glucocorticoid treatment earlier in childhood and adolescence show dose-response associations with diurnal cortisol levels.

Heightened levels of glucocorticoids in children and adolescents have previously been linked to prolonged changes in the diurnal regulation of the stress-hormone cortisol, a glucocorticoid regulated by the hypothalamic-pituitary-adrenal-axis (HPA-axis). To address this question, we examined the salivary cortisol awakening response (CAR) and daily cortisol output in 36 children and adolescents (25 girls/11 boys) aged 7-16 years previously treated with glucocorticoids for nephrotic syndrome or rheumatic disorder and 36 healthy controls. Patients and controls did not significantly differ in the CAR or diurnal cortisol output; however, sex-dependent group differences were observed. Specifically, female patients had a higher CAR relative to female controls, while male patients had higher daily cortisol levels compared to male controls. Notably, CAR in female patients and daily cortisol levels in male patients showed a positive linear relationship with the mean daily glucocorticoid doses administered during treatment. The observed dose-response associations suggest that glucocorticoid therapy during childhood and adolescence might trigger long-term changes in HPA-axis regulation, which may differ for males and females.

Individual and Day-to-Day Differences in Active Coping Predict Diurnal Cortisol Patterns among Early Adolescent Girls.

Prior work has identified alterations in activity of the hypothalamic-pituitary-adrenal axis as a potential mechanism underlying stress-induced emotional health problems, which disproportionately impact girls beginning in mid-adolescence. How adolescent girls differ from one another in dispositional coping tendencies and shift specific coping strategies in response to varying stressors have been theorized as important predictors of their adaptation, health, and well-being during this dynamic period of development. The goal of this study was to examine whether individual and day-to-day (within-person) differences in adolescent girls' coping responses are associated with daily patterns of hypothalamic-pituitary-adrenal axis activity, indexed by cortisol. Participants were 122 early adolescent girls (M age = 12.39) who provided three saliva samples per day for 3 days and completed daily coping reports, as well as a standard coping survey. Participants and primary caregivers also completed objective life stress interviews. On average, girls who were more likely to respond to interpersonal stress with voluntary engagement (active) coping exhibited generally adaptive daily physiological regulation-steeper diurnal cortisol slopes, lower total diurnal cortisol output, and lower cortisol awakening responses. Chronic interpersonal stress level significantly moderated these associations in different ways for two distinct components of the diurnal pattern-the slope and cortisol awakening responses. Regarding within-person differences, using active coping more than usual was associated with higher waking cortisol the following morning, which may help to prepare adolescent girls for perceived daily demands. These findings highlight the interactive influence of stress and coping in the prediction of daily hypothalamic-pituitary-adrenal axis activity and support the stress-buffering role of active coping for adolescent girls.

Purposeful Engagement, Healthy Aging, and the Brain.

Research on psychological well-being in later life has identified strengths and vulnerabilities that occur with aging. We review the conceptual and philosophical foundations of a eudaimonic model of well-being and its empirical translation into six key dimensions of positive functioning. We also consider its implications for health, broadly defined. Numerous findings from national longitudinal samples of U.S. adults are described. They show declining scores on purpose in life and personal growth with aging, but also underscore the notable variability among older persons in these patterns. Recently, health benefits have been identified among older adults who maintain high levels of a particular aspect of well-being, namely, purposeful life engagement. These benefits include extended longevity, reduced risk for various disease outcomes, reduced physiological dysregulation, and gene expression linked to better inflammatory profiles. The brain mechanisms that underlie such outcomes are also examined via a focus on affective style. Adults with higher levels of purpose in life show more rapid recovery from negative stimulus provocation, whereas those with higher well-being overall show sustained activation of reward circuitry in response to positive stimuli, and this pattern is associated with lower diurnal cortisol output. Volumetric findings (right insular gray matter volume) have also been linked with eudaimonic well-being. Eudaimonic well-being predicts better health and longer lives, and thus constitutes an important direction for future research and practice. Intervention studies designed to promote well-being, including among those suffering from psychological disorders, are briefly described.

The cortisol awakening response and cognition across the adult lifespan

Although the hippocampus is thought to play a central role in the regulation of the cortisol awakening response (CAR), results from past studies examining the relationship between the CAR and hippocampal-mediated memory and cognition have been mixed. Inconsistent findings may be due to the use of cortisol samples collected on only 1–2days since reduced sampling can permit unstable situational factors to bias results. We used cortisol assessments from 10 consecutive days to test the relationship of the CAR to episodic memory, working memory, and processing speed in a sample of healthy young, middle-aged, and older adults (age range: 23–79years; N=56). We tested if the relationship between the CAR and cognition would depend upon age and also tested if other cortisol measures, specifically waking cortisol, diurnal cortisol output (i.e., area under the curve) and diurnal cortisol slope (linear and quadratic), would be related to cognition. We found that a more positive CAR slope was related to better episodic memory and that this relationship did not depend upon age. The CAR was not significantly related to working memory. The relationship of the CAR to processing speed was not significant when using a CAR measure that corrected for non-compliant cortisol sampling. We also found that higher waking cortisol was significantly related to better working memory, but not episodic memory or processing speed. Neither diurnal cortisol output nor diurnal linear cortisol slope was significantly related to cognitive functioning. Future work should investigate the mechanisms underpinning the relationship of the cortisol awakening process to cognitive functioning.

The psychophysiological impact of childhood autism spectrum disorder on siblings

ObjectiveThe negative impact of caring for a child with autism spectrum disorder (ASD) on parents’ psychophysiological functioning has been widely evidenced. However, siblings, who also face emotional, social and physical challenges associated with having a brother/sister with ASD, have been less widely studied. This study examined the psychophysiological impact of childhood ASD on siblings. MethodsA sample of 25 siblings of children with ASD (and their mothers) and a control group of 20 siblings of neuro-typical children (and their mothers) completed questionnaires assessing: (a) demographic and lifestyle information, (b) family characteristics, (c) child behaviour problems, (d) social support and (e) depressive symptomology. Saliva samples were collected at several time points on two consecutive days, and estimates of the cortisol awakening response (CAR), diurnal cortisol slope and mean diurnal cortisol output were derived. ResultsTotal depressive symptoms were higher in siblings of children with ASD compared with controls. Group differences with respect to depressive symptomology were driven more by emotional than functional problems. With respect to physiological functioning, groups were comparable on all cortisol indices. In siblings of children with ASD, social support, especially from parents and close friends, predicted total depressive symptoms, as did the behaviour problems of their brother/sister with ASD. ConclusionSiblings of children with ASD experience greater emotional problems and overall depressive symptoms compared with a control group. Interventions that enhance social support, as well as helping siblings better understand the behaviour problems of their brother/sister with ASD, might be effective for alleviating depressive symptoms.

Post-traumatic disorder symptoms and blunted diurnal cortisol production in partners of prostate cancer patients

Prostate cancer (PC) is the most common cancer diagnosed in men, and research suggests that coping with this illness can cause significant distress in patients as well as their partners. This study examined the relationship of caregiving for a partner with PC with diurnal cortisol output in women between the ages of 42 and 75 years old. Participants were women whose partners had PC (n = 19) and women who were in relationships with men with no diagnosed medical illness (n = 26). Women provided saliva samples (4 times per day over 3 days) in their natural environment. The Structured Clinical Interview for DSM-IV Axis-I Disorders was also conducted to assess for the presence of post-traumatic stress disorder (PTSD) and major depression. Partners of men with PC had lower daily cortisol output across the three days than controls, F(1,444.08) = 20.72, p<.001). They were also more likely to report PTSD symptoms with 68.4% of PC partners fulfilling criteria for sub-threshold PTSD as compared to 23.1% of controls (χ(2) = 11.30, p = .01). Mixed model analyses revealed that the presence of sub-threshold PTSD symptoms significantly predicted cortisol production, F(1,419.64) = 5.10, p<.01). Regardless of caregiver status, women who reported at least sub-threshold PTSD symptoms had lower cortisol production than those with no PTSD symptoms. Major depression did not explain differences in cortisol production between partners of PC patients and controls. Although these findings are preliminary, they highlight the importance of developing interventions aimed at reducing risk of psychopathology in partners of men with PC.