An integrative model linking traumatization, cortisol dysregulation and posttraumatic stress disorder: Insight from recent hair cortisol findings

Glucocorticoid receptor gene methylation moderates the association of childhood trauma and cortisol stress reactivity

Exposure to childhood trauma (CT) has been linked to sustained dysregulations of major stress response systems, including findings of both exaggerated and attenuated hypothalamus-pituitary-adrenal (HPA) axis activity. Likewise, CT constitutes a common risk factor for a broad range of psychiatric conditions that involve distinct neuroendocrine profiles. In this study, we investigated the role of epigenetic variability in a stress-related gene as a potential mediator or moderator of such differential trajectories in CT survivors. For this, we screened adult volunteers for CT and recruited a healthy sample of 98 exposed (67 with mild-moderate, 31 with moderate-severe exposure) and 102 control individuals, with an equal number of males and females in each group. DNA methylation (DNA_M) levels of the glucocorticoid receptor exon 1F promoter (NR3C1-1F) at functionally relevant sites were analyzed via bisulfite pyrosequencing from whole blood samples. Participants were exposed to a laboratory stressor (Trier Social Stress Test) to assess salivary cortisol stress responses. The major finding of this study indicates that DNA_M in a biologically relevant region of NR3C1-1F moderates the specific direction of HPA-axis dysregulation (hypo- vs. hyperreactivity) in adults exposed to moderate-severe CT. Those trauma survivors with increased NR3C1-1F DNA_M displayed, on average, 10.4 nmol/l (62.3%) higher peak cortisol levels in response to the TSST compared to those with low DNA_M. In contrast, unexposed and mildly-moderately exposed individuals displayed moderately sized cortisol stress responses irrespective of NR3C1-1F DNA_M. Contrary to some prior work, however, our data provides no evidence for a direct association of CT and NR3C1-1F DNA_M status. According to this study, epigenetic changes of NR3C1-1F may provide a more in-depth understanding of the highly variable neuroendocrine and pathological sequelae of CT.

Link between children's hair cortisol and psychopathology or quality of life moderated by childhood adversity risk

The hypothalamus-pituitary-adrenal axis (HPAA) and its end product, the glucocorticoid cortisol, has been shown to be associated with psychopathology. Determining cortisol concentrations in hair (HCC) allows the investigation of long-term HPAA-activity. There is a significant scarcity of studies investigating the link between HCC and psychopathology and quality of life in child and adolescent samples. In addition, as the HPAA constitutes a feedback system enabling adaption to environmental demands, it is important to consider the socio-environmental context that the children grow up in. We therefore investigated the associations between child HCC and psychopathology/quality of life and compared these links in two groups of five to 12-year-olds: children living with mothers who report experiences of early life maltreatment (ELM) (high-risk group) and children whose mothers did not report any ELM (low-risk group). We expected that, under conditions of a high-risk environment, elevated HPAA-functioning would be associated with low levels of psychopathology and high levels of quality of life in children. Under low-risk conditions, elevated HPAA-functioning would be associated with high levels of psychopathology and low levels of quality of life in children. For the complete sample of N = 130 children, three-months HCC did not significantly predict child psychopathology or quality of life. However, there was a significant moderating effect of group membership: In the high-risk group, high levels of HCC were significantly associated with high levels of self-reported quality of life. In the low-risk group, there was no association between HCC and self-reported quality of life. For child psychopathology, in the low-risk group, high levels of HCC were significantly associated with high levels of teacher reported behavior problems, whereas in the high-risk group, the association did not reach significance. Our results underline the importance of accounting for the social environment children grow up in when investigating the link between HCC and child psychopathology and quality of life.

Hair cortisol concentrations in war-affected adolescents: A prospective intervention trial

Temporal examinations of the biological signature of stress or trauma in war-affected populations are seldom undertaken. Moreover, few studies have examined whether stress biomarkers track biological sensitivity to brief interventions targeting the improvement of psychosocial wellbeing. Our study is the first to prospectively examine, in war-affected adolescents, the associations between hair cortisol concentrations (HCC) and self-reports of stress, insecurity, posttraumatic reactions, and lifetime trauma. We conducted a randomized controlled trial to test the impact of an 8-week intervention based on profound stress attunement. We collected data for a gender-balanced sample of 733 Syrian refugee (n = 411) and Jordanian non-refugee (n = 322) adolescents (12-18 years), at three time-points. We used growth mixture models to classify cortisol trajectories, and growth models to evaluate intervention impact on stress physiology. We observed three trajectories of HCC: hypersecretion, medium secretion, and hyposecretion (9.6%, 87.5% and 2.9% of the cohort, respectively). For every one percent increase in levels of insecurity, adolescents were 0.02 times more likely to have a trajectory of hypersecretion (95% CI: 1.00, 1.03, p = 0.01). For each additional symptom of posttraumatic stress reported, they were 0.07 times less likely to show hyposecretion (95% CI: 0.89, 0.98, p = 0.01). Indeed, stronger posttraumatic stress reactions were associated with a pattern of within-individual cortisol dysregulation and medium secretion. Overall, HCC decreased by a third in response to the intervention (95% CI: -0.19, -0.03, p = 0.01). While the intervention decreased HCC for youth with hypersecretion and medium secretion, it increased HCC for youth with hyposecretion (95% CI: 0.22, 1.16, p = 0.004), relative to controls. This suggests a beneficial regularization of cortisol levels, corroborating self-reports of improved psychosocial wellbeing. We did not find evidence to suggest that gender, resilience, or posttraumatic stress disorder influenced the strength or direction of responses to the intervention. This robust impact evaluation exemplifies the utility of biomarkers for tracking physiological changes in response to interventions over time. It enhances the understanding of trajectories of endocrine response in adverse environments and patterns of stress responsivity to ecological improvement.

Measuring Resilience to Operational Stress in Canadian Armed Forces Personnel

Adaptability to stress is governed by innate resilience, comprised of complex neuroendocrine and immune mechanisms alongside inherited or learned behavioral traits. Based on their capacity to adapt, some people thrive in stressful situations, whereas others experience maladaptation. In our study, we used state-of-the-art tools to assess the resilience level in individuals, as well as their susceptibility to developing military stress-induced behavioral and cognitive deficits. To address this complex question, we tested Canadian Armed Forces (CAF) personnel in three distinct stress environments (baselines): during predeployment training, deployment in Afghanistan, and readjustment upon return to Canada. Our comprehensive outcome measures included psychometric tests, saliva biomarkers, and computerized cognitive tests that used the Cambridge Neuropsychological Automated Test Battery. Participants were categorized based on initial biomarker measurements as being at low-, moderate-, or high stress-maladaptation risk. Biomarkers showed significant changes (ds = 0.56 to 2.44) between baselines, calculated as "delta" changes. Participants at low stress-maladaptation risk demonstrated minimal changes, whereas those at high stress-maladaptation risk showed significant biomarker variations. The psychometric patterns and cognitive functions were likewise affected across baselines, suggesting that the panel of saliva stress biomarkers could be a useful tool for determining the risk of stress maladaptation that can cause psychological and cognitive decline.

Determinants of hair cortisol concentration in children: A systematic review

BACKGROUND

Several factors are known contribute to hair cortisol concentration (HCC) in adults. However, there is less research on determinants of HCC in children and adolescents. HCC is a valuable tool for medical research pertaining to the hypothalamic-pituitary-adrenal (HPA) axis. This review aims to assess the extent to which established determinants of HCC in adults have been consistently reported in children (birth - 18 years) and to identify determinants of HCC specific to this age group.

METHODS

Eligible studies were identified, selected and appraised as per PRISMA-P guidelines and as detailed in our systematic review protocol, registered on PROSPERO (registration number CRD42017056220). In view of contrasting methods and measures, a meta-analysis could not be done but a qualitative synthesis was performed.

RESULTS

Thirty-six studies were included in the analysis. Higher HCC is associated with male sex and anthropometry, particularly increased body mass index and waist circumference. There is preliminary evidence to suggest that socio-economic status is inversely related to child HCC, particularly with reference to caregiver education and income. Of note, most of the studies analysing socio-economic variables were performed in relatively equal societies. Hair wash frequency and use of hair products and treatments do not affect HCC when proximal segments of hair are used. There is conflicting evidence regarding the relationship between HCC and age in children and adolescents. Further investigation is required to better delineate if and how the following are associated with HCC in children: hair colour, hair type, exposure to trauma and stressors, psychiatric illness, atopic illness, steroid use (including topical and inhaled steroids) and perinatal variables.

CONCLUSIONS

Sex and anthropometry are potential confounders and should be considered for adjustment in hair cortisol research. Hair wash frequency and use of hair products and treatments are not important confounders when proximal hair segments are used. A better understanding of HCC in children in relation to exposure to trauma and stressors is required before it can be used as a biomarker, particularly in terms of vulnerable developmental stages, definition and measurement of stress, and temporal relationship to stressors. Age, SES and other correlates also warrant further investigation.

The association of depression and posttraumatic stress disorder with the metabolic syndrome in a multi-ethnic cohort: the HELIUS study

PURPOSE

Depression and posttraumatic stress disorder (PTSD) may be linked to the metabolic syndrome (MetS). Consistency of this association across ethnic groups and the influence of comorbidity of depression/PTSD were examined.

METHODS

Cross-sectional baseline data from the HELIUS study were used (4527 Dutch, 2999 South-Asian Surinamese, 4058 African Surinamese, 2251 Ghanaian, 3522 Turkish and 3825 Moroccan participants). The Patient Health Questionnaire-9 (PHQ-9) (score range 0-27) measured depressive symptoms. A 9-item questionnaire (score range 0-9) measured PTSD symptoms. The MetS was defined according to the International Diabetes Federation. The association of a depressed mood (PHQ-9 sum score ≥ 10) and severe PTSD symptoms (sum score ≥ 7) with the MetS was examined using logistic regression. Interaction with ethnicity and between a depressed mood and severe PTSD symptoms was tested.

RESULTS

A depressed mood was associated with the MetS [OR (95% CI) = 1.37 (1.24-1.51)] in the total sample and consistent across ethnic groups (p values for interaction all > 0.05). Severe PTSD symptoms were significantly associated with the MetS in the Dutch [OR (95% CI) = 1.71 (1.07-2.73)]. The South-Asian Surinamese, Turks and Moroccans showed weaker associations than the Dutch (p values for interaction all < 0.05). A depressed mood and severe PTSD symptoms did not interact in the association with the MetS (p values for interaction > 0.05).

CONCLUSIONS

A depressed mood was consistently associated with the MetS across ethnic groups, but the association between severe PTSD symptoms and the MetS maybe ethnicity dependent. The association with the MetS was not different in case of depressed mood/severe PTSD symptoms comorbidity.

Biological stress indicators as risk markers for increased alcohol use following traumatic experiences

Alcohol misuse is a common sequela of traumatic event experiences causing considerable morbidity and mortality. Although biological stress indicators have been identified as useful risk markers for the development of trauma-related disorders, no such biological indicators exist for the risk of increased alcohol use after trauma exposure. This is the first study to prospectively investigate the predictive value of long-term cortisol levels and acute stress reactivity for the risk of increased alcohol use following traumatic events. Male soldiers were examined before and 12 months following deployment using a standardized diagnostic interview. We analyzed the moderating role of baseline hair cortisol concentrations (HCCs, n = 153) as well as baseline salivary cortisol and alpha-amylase stress reactivity in response to a laboratory stressor (n = 145) in the association between new-onset traumatic events (according to the DSM-IV A1 criterion) and subsequent daily alcohol use. No main effects of pre-traumatic HCC or salivary stress markers on subsequent change in alcohol use were observed. However, we found that with decreasing HCC, the number of new-onset traumatic events was more strongly associated with subsequent alcohol use independent from changes in posttraumatic stress disorder symptoms. No such relation was seen for the acute stress reactivity data. Taken together, this study provides first evidence suggesting that individual differences in long-term cortisol regulation are involved in the association between traumatic experiences and subsequent alcohol use. HCC may thus serve as a potential target in the early identification of individuals vulnerable for increased alcohol use following traumatic events.

Hair Cortisol in Twins: Heritability and Genetic Overlap with Psychological Variables and Stress-System Genes

Hair cortisol concentration (HCC) is a promising measure of long-term hypothalamus-pituitary-adrenal (HPA) axis activity. Previous research has suggested an association between HCC and psychological variables, and initial studies of inter-individual variance in HCC have implicated genetic factors. However, whether HCC and psychological variables share genetic risk factors remains unclear. The aims of the present twin study were to: (i) assess the heritability of HCC; (ii) estimate the phenotypic and genetic correlation between HPA axis activity and the psychological variables perceived stress, depressive symptoms, and neuroticism; using formal genetic twin models and molecular genetic methods, i.e. polygenic risk scores (PRS). HCC was measured in 671 adolescents and young adults. These included 115 monozygotic and 183 dizygotic twin-pairs. For 432 subjects PRS scores for plasma cortisol, major depression, and neuroticism were calculated using data from large genome wide association studies. The twin model revealed a heritability for HCC of 72%. No significant phenotypic or genetic correlation was found between HCC and the three psychological variables of interest. PRS did not explain variance in HCC. The present data suggest that HCC is highly heritable. However, the data do not support a strong biological link between HCC and any of the investigated psychological variables.

The individual contribution of DSM 5 symptom clusters of PTSD, life events, and childhood adversity to frontal oscillatory brain asymmetry in a large sample of active combatants

Post-Traumatic Stress Disorder (PTSD) has been linked to deviations in lateralized frontal functional oscillatory activity. This is possibly because left and right DLPFC have differential roles in regulating both memory and stress response, which are both dysfunctional in PTSD. However, previous results are heterogeneous, and could be attributable to individual symptom clusters, traumatic or aggressive life events, early life stress, or the interaction of these factors. In a large sample of active combatants (N=401), we regressed these factors on frontal electroencephalography (EEG) asymmetry across 5 frequency bands (delta: 2-4Hz; theta: 4-8Hz; alpha: 8-12Hz; beta: 12-24Hz; gamma: 24-48Hz). Negative cognition and mood was associated with stronger relative left delta and theta band power. Traumatic life events showed stronger right alpha and beta band power. Traumatic life events in interaction with hyperarousal predicted stronger relative right left-right imbalance (theta, alpha, and beta bands), whereas childhood adversity, in interaction with negative cognition and mood, predicted stronger relative left left-right imbalance (delta, theta, alpha and beta bands). The contribution of lateralized DLPFC dysfunction to PTSD is thus dependent on the individual complexities of subsymptom clusters and life history, and future studies need to take these factors into account.

Reduced hair cortisol after maltreatment mediates externalizing symptoms in middle childhood and adolescence

BACKGROUND

The enduring impact of childhood maltreatment on biological systems and ensuing psychopathology remains incompletely understood. Long-term effects of stress may be reflected in cumulative cortisol secretion over several months, which is now quantifiable via hair cortisol concentrations (HCC). We conducted a first comprehensive investigation utilizing the potential of hair cortisol analysis in a large sample of maltreated and nonmaltreated children and adolescents.

METHOD

Participants included 537 children and adolescents (3-16 years; 272 females) with maltreatment (n = 245) or without maltreatment histories (n = 292). Maltreated subjects were recruited from child protection services (CPS; n = 95), youth psychiatric services (n = 56), and the community (n = 94). Maltreatment was coded using the Maltreatment Classification System drawing on caregiver interviews and complemented with CPS records. Caregivers and teachers reported on child mental health. HCC were assessed in the first 3 cm hair segment.

RESULTS

Analyses uniformly supported that maltreatment coincides with a gradual and dose-dependent reduction in HCC from 9 to 10 years onwards relative to nonmaltreated controls. This pattern emerged consistently from both group comparisons between maltreated and nonmaltreated subjects (27.6% HCC reduction in maltreated 9-16-year-olds) and dimensional analyses within maltreated subjects, with lower HCC related to greater maltreatment chronicity and number of subtypes. Moreover, both group comparisons and dimensional analyses within maltreated youth revealed that relative HCC reduction mediates the effect of maltreatment on externalizing symptoms.

CONCLUSIONS

From middle childhood onwards, maltreatment coincides with a relative reduction in cortisol secretion, which, in turn, may predispose to externalizing symptoms.

Pre-treatment cortisol awakening response predicts symptom reduction in posttraumatic stress disorder after treatment

Dysfunction of the HPA-axis has frequently been found in the aftermath of trauma exposure with or without PTSD. Decreasing HPA-axis reactivity to different stress cues has been reported during PTSD treatment. The cortisol awakening response (CAR_i) is a well-validated, standardized measure of HPA-axis reactivity which can be easily acquired in the clinical setting. Whether CAR_i changes over time in traumatized individuals are specific to PTSD treatment is unknown. Furthermore, a possible role for the baseline CAR_i in predicting symptom reduction after treatment in PTSD has not been examined before. To answer these questions, a cohort study was conducted in which the awakening cortisol was measured in both PTSD (N=41) and non-PTSD (N=25) combat-exposed male subjects. Measurements took place at inclusion and 6-8 months after inclusion for both the PTSD and the non-PTSD group. During the 6-8 months interval, PTSD patients received trauma-focused focused psychotherapy, whereas non-PTSD patients received no treatment. We found a decrease in the CAR_i over time in both groups, suggesting it was not specific to PTSD or the effect of treatment. Therefore, caution is warranted when attributing diminished HPA-axis reactivity over time to effects of PTSD treatment. Second, CAR_i prior to treatment predicted PTSD symptom reduction (CAPS score change) after treatment, and accounted for 10% of the variance, even when adjusted for changes in depressive symptoms and medication use during the study period. A putative role emerges for CAR_i as a predictive biomarker of symptom reduction in male individuals with combat-related PTSD.

Hair cortisol in relation to acute and post-traumatic stress symptoms in children and adolescents

BACKGROUND

We report on the preliminary results of two independent studies that (1) compare the hair cortisol concentrations (HCC) of healthy controls with patients displaying post-traumatic stress symptoms (PTSS, study 1+2), (2) investigate whether pre-trauma HCC are predictive for the development of acute stress symptoms (ASS) and PTSS (study 1) and (3) determine whether HCC correlate with PTSS in a clinical sample of children (study 2).

METHODS

In study 1, the clinical symptoms of 35 minors were examined one (T1) and seven weeks (T2) after surgery following an accident. Hair samples were taken after the accident that reflect cortisol secretion over the past three months before the accident (healthy controls). In study 2, HCC and PTSS symptoms were cross-sectionally assessed in 22 minors who had experienced a psychological trauma.

RESULTS

The HCC of patients with PTSS were lower than the HCC of healthy controls (study 1+2). Secondary analyses showed that HCC were significantly lower in male PTSS patients than in male healthy controls, whereas the HCC in females were comparably low in both groups. Pre-trauma HCC did not predict the total ASS and PTSS scores (study 1) and HCC were not directly related to the total PTSS scores (study 2).

Stress-related and basic determinants of hair cortisol in humans: A meta-analysis

The analysis of hair cortisol concentrations (HCC) is a relatively new strategy to measure long-term cumulative cortisol levels, which is increasingly used in psychoneuroendocrinological research. Here, we conduct a first comprehensive meta-analysis of HCC research based on aggregated data from a total of 124 (sub)samples (66 independent studies; total N=10,289). We seek to answer two central questions: (i) Which covariates and basic features of HCC need to be considered in future research? (ii) What are the main determinants of HCC in terms of chronic stress exposure and mental health? Concerning basic characteristics, our findings identify several covariates to be considered (age, sex, hair washing frequency, hair treatment, oral contraceptive use), confirm a decline of HCC from the first to the second proximal 3cm hair segment, and show positive associations between HCC and short-term salivary cortisol measures. Regarding chronic stress, we show that stress-exposed groups on a whole exhibit 22% increased HCC. This long-term cortisol hypersecretion emerges particularly when stress is still ongoing at the time of study (+43% HCC) but is not present in conditions of past/absent stress (-9% HCC, n.s.). We also report evidence for 17%-reduced HCC in anxiety disorders, such as PTSD. Interestingly, no consistent associations with mood disorders and self-reports of perceived stress, depressiveness or social support are found. However, our findings reveal positive associations of HCC with stress-related anthropometric (body mass index, waist-to-hip ratio) and hemodynamic measures (systolic blood pressure). These meta-analytic results are discussed in the light of their practical implications and important areas for future inquiry are outlined.

Neuroendocrine and neuroimmune markers in PTSD: pre-, peri- and post-trauma glucocorticoid and inflammatory dysregulation

We review current knowledge on how posttraumatic stress disorder (PTSD) is associated with dysregulation of the most commonly studied markers of the endocrine and immune systems pre-, peri- and post-trauma. Lower basal cortisol output, enhanced glucocorticoid receptor function, and a proinflammatory state have been most consistently found in PTSD, with considerable variability among studies and participants. Longitudinal research is scarce, but there is converging evidence that biological dysregulation is present before PTSD onset. Biological dysregulation may become more apparent with increasing time since trauma, and may be reversible with and predict effective treatment. However, considering the variability of findings and the complex interplay of these systems with other factors, the current clinical application of these findings remains limited.

The utility of hair cortisol concentrations in the prediction of PTSD symptoms following traumatic physical injury

RATIONALE

Although cortisol alterations have been associated with posttraumatic stress disorder (PTSD) and PTSD symptoms (PTSS), the direction of association is mixed. Cortisol which is measured in blood, saliva, or urine is subject to transient factors that may confound results. Recent advances in cortisol sampling techniques provide novel opportunities to address these inconsistencies. Hair cortisol sampling is a non-invasive method for the retrospective assessment of long-term integrated cortisol, yet its utility at predicting PTSS has not been assessed in acute injury victims.

OBJECTIVE

The aim of this prospective study was to examine whether higher levels of hair cortisol concentrations (HCC) were associated with increases in PTSS following traumatic physical injury.

METHOD

From January 2012 to May 2013, injury victims admitted to a level-1 Midwestern trauma center were recruited during their routine trauma clinic appointment within 30-days post-injury. Thirty participants had sufficient hair length to obtain 3-cm hair samples for cortisol assay. These participants completed PTSS assessments in relation to their recent injury at both the baseline and follow-up assessments (within 30- and 60-days post-injury, respectively).

RESULTS

Hierarchical regression analyses - which controlled for baseline PTSS, age, and sex - revealed that higher HCC predicted significant increases in overall PTSS at follow-up. Higher HCC also predicted increases in the avoidance/numbing subscale symptoms of PTSS. Dividing the avoidance symptoms and numbing symptoms into two separate clusters (consistent with the 4-factor DSM-5 model of PTSD) revealed that HCC was only marginally associated with numbing, but not with avoidance symptoms.

CONCLUSION

Hair sampling is a feasible method for assessing integrated cortisol levels soon after traumatic physical injury. This study suggests that elevated HCC may serve as a biomarker of risk for the development of posttraumatic symptomatology, and identifies specific symptoms that may be targeted for intervention in those with high HCC in the aftermath of injury.

The role of automatic defensive responses in the development of posttraumatic stress symptoms in police recruits: protocol of a prospective study

Background: Control over automatic tendencies is often compromised in challenging situations when people fall back on automatic defensive reactions, such as freeze-fight-flight responses. Stress-induced lack of control over automatic defensive responses constitutes a problem endemic to high-risk professions, such as the police. Difficulties controlling automatic defensive responses may not only impair split-second decisions under threat, but also increase the risk for and persistence of posttraumatic stress disorder (PTSD) symptoms. However, the significance of these automatic defensive responses in the development and maintenance of trauma-related symptoms remains unclear due to a shortage of large-scale prospective studies. Objective: The 'Police-in-Action' study is conducted to investigate the role of automatic defensive responses in the development and maintenance of PTSD symptomatology after trauma exposure. Methods: In this prospective study, 340 police recruits from the Dutch Police Academy are tested before (wave 1; pre-exposure) and after (wave 2; post-exposure) their first emergency aid experiences as police officers. The two waves of data assessment are separated by approximately 15 months. To control for unspecific time effects, a well-matched control group of civilians (n = 85) is also tested twice, approximately 15 months apart, but without being frequently exposed to potentially traumatic events. Main outcomes are associations between (changes in) behavioural, psychophysiological, endocrine and neural markers of automatic defensive responses and development of trauma-related symptoms after trauma exposure in police recruits. Discussion: This prospective study in a large group of primary responders enables us to distinguish predisposing from acquired neurobiological abnormalities in automatic defensive responses, associated with the development of trauma-related symptoms. Identifying neurobiological correlates of (vulnerability for) trauma-related psychopathology may greatly improve screening for individuals at risk for developing PTSD symptomatology and offer valuable targets for (early preventive) interventions for PTSD.

Hair cortisol concentrations and cortisol stress reactivity in generalized anxiety disorder, major depression and their comorbidity

Studies investigating cortisol secretion in patients with generalized anxiety disorder (GAD) have reported heterogeneous findings. Further, current knowledge on the specificity of endocrine changes for GAD and/or comorbid major depression (MD) is limited. Hence, the current study investigated long-term integrated cortisol secretion, as indexed by hair cortisol concentrations (HCC), and experimentally-induced cortisol stress reactivity in relation to GAD, MD and their comorbidity. Carefully characterized groups of 17 GAD patients including 8 with comorbid MD (GAD-MD), 12 MD patients and 21 healthy controls were recruited. Alongside psychometric data, HCC (N = 43) and salivary cortisol stress reactivity in response to the Trier Social Stress Test (N = 45) were determined. Findings revealed that MD patients exhibited lower HCC compared to controls and GAD patients, with no differences between the latter two groups. Interestingly, when the GAD group was separated into two groups based on MD comorbidity, lower HCC in MD patients were found compared to controls and GAD-noMD patients, but did not show differences when compared to GAD-MD patients. No HCC differences were seen between GAD-MD or GAD-noMD patients and healthy controls. No TSST group differences emerged. Our findings suggest MD to be related to long-term attenuation in cortisol secretion. While no group differences emerged between patients with GAD, neither with nor without MD, and controls, the current results provide tentative evidence that MD determines long-term endocrine changes, with pure GAD showing a distinct pattern. Future studies are needed to confirm our findings in larger samples of pure and comorbid groups.