Diurnal Cortisol Research Articles

Timing sensitivity of prenatal cortisol exposure and neurocognitive development.

Prenatal glucocorticoid exposure has been negatively associated with infant neurocognitive outcomes. However, questions about developmental timing effects across gestation remain. Participants were 253 mother-child dyads who participated in a prospective cohort study recruited in the first trimester of pregnancy. Diurnal cortisol was measured in maternal saliva samples collected across a single day within each trimester of pregnancy. Children (49.8% female) completed the Bayley Mental Development Scales, Third Edition at 6, 12, and 24 months and completed three observational executive function tasks at 24 months. Structural equation models adjusting for sociodemographic covariates were used to test study hypotheses. There was significant evidence for timing sensitivity. First-trimester diurnal cortisol (area under the curve) was negatively associated with cognitive and language development at 12 months and poorer inhibition at 24 months. Second-trimester cortisol exposure was negatively associated with language scores at 24 months. Third-trimester cortisol positively predicted performance in shifting between task rules (set shifting) at 24 months. Associations were not reliably moderated by child sex. Findings suggest that neurocognitive development is sensitive to prenatal glucocorticoid exposure as early as the first trimester and underscore the importance of assessing developmental timing in research on prenatal exposures for child health outcomes.

Multimodal examination of daily stress rhythms in chronic Cannabis users.

Chronic cannabis users frequently report stress relief as their primary reason for use. The endocannabinoid system is involved in the neuroendocrine stress response, and diurnal cortisol rhythms may be disrupted in chronic cannabis users. The objectives were to determine whether cannabis users demonstrate disruptions in diurnal stress rhythms and examine the acute effects of cannabis on stress-related outcomes in cannabis users' natural environments. Eighty-two participants (39 cannabis users, 43 non-users) collected saliva samples to quantify cortisol concentrations and provided subjective stress ratings at 8 time points throughout the day. They wore a medical-grade wearable device for 24h that recorded physiological indicators of stress (heart rate variability, electrodermal activity). Cannabis users collected additional saliva samples before and after cannabis use to examine acute effects of cannabis use. Cannabis users exhibited significant dysregulations in diurnal cortisol rhythms, including a blunted cortisol awakening response, flattened diurnal cortisol slope, and elevated afternoon cortisol concentrations. There were no differences in diurnal heart rate variability or electrodermal activity except for elevated evening heart rate in cannabis users. Finally, there were significant decreases in cortisol, subjective stress, and electrodermal activity following acute cannabis use in cannabis users' natural environment. These results provide evidence of dysregulated diurnal cortisol rhythms in cannabis users that were related to later waking times and acute stress-relieving properties of cannabis use in naturalistic environments. Future research should examine the direction of the relationship between cannabis use and diurnal cortisol rhythms and potential implications for other psychological disorders.

Assessing the psychobiological demands of high-fidelity training in pre-hospital emergency medicine

BackgroundIndividuals who provide critical emergency care mount rapid psychobiological responses when faced with an incident. These responses are adaptive and ensure resources at time of demand; however, frequent activation with minimal opportunity for recovery can have negative consequences for health and wellbeing. Monitoring individuals in real emergency situations would provide an understanding of their stress responses during the provision of critical care; however, this presents logistical challenges. An alternative is to assess individuals during high-fidelity training scenarios. This is the first comprehensive assessment of psychobiological responding during continuous high-fidelity training in pre-hospital emergency medicine.MethodsA sample of doctors and paramedics (N = 27) participated during 10 days of training and a weekend of no activities. Training involved the acquisition of human factors, non-technical and surgical skills, and their application in complex high-fidelity scenarios including road-traffic accidents, firearms incidents, and swift water rescue operations. On each day participants reported levels of state, cognitive, and somatic anxiety, and self-confidence following waking and before sleep, and their anticipated (at wake) and experienced (before sleep) demands of the day. Saliva samples were obtained each day for assessment of diurnal cortisol indices and the Cortisol Awakening Response (CAR). Garmin smartwatches were worn throughout for the collection of heart rate and HRV-derived stress.ResultsThere were significant (p < 0.001) differences across days for state, cognitive, and somatic anxiety; self-confidence; anticipated and experienced demands; aggregated measures of heart rate and HRV-derived stress; levels of cortisol at waking (p = 0.002) and for the CAR (p < 0.001). Measures of psychobiological responding during training were distinct from the weekend and the highest levels of psychobiological responding occurred on days characterised by greater anticipated and experienced demands.DiscussionThis high-fidelity training is typical of the day-to-day requirements of emergency services and these observations are representative of functioning during real-life critical care emergencies. Increased responding during times of demand is adaptive; however, frequent and sustained responding increases allostatic load and is a contributor to burnout. As burnout is a significant concern in emergency medicine, this study identifies patterns of responding and recovery that may impact upon longer-term health and wellbeing.

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.

Attention to social threat predicts diurnal cortisol dynamics during the high school transition

Adolescence is a developmental period marked by significant social shifts accompanied by concurrent changes across biological, cognitive, and emotional domains. Within adolescence, the high school transition is a pivotal time for youth that is ripe with opportunities yet has the potential to disrupt functioning. An increasingly sophisticated understanding of health and developmental biology indicates that the hypothalamic-pituitary-adrenal (HPA) axis plays an important role in transducing social experiences into physiological changes that have long-term impacts on health and wellbeing. There is reason to believe that attentional biases to social threat could impact cortisol, a steroid hormone indexing activity of the HPA axis, during the high school transition. The present study examined associations between attentional biases to socially threatening stimuli, measured using the Affective Posner paradigm, and components of the diurnal cortisol rhythm among youth across the first two days of high school. Participants included 67 youth (N = 504 saliva samples) with a mean age of 12.86 years and a relatively equal split with regard to both sex assigned at birth and gender identity (54% male; 54% boys). Findings build upon and extend previous work by demonstrating that greater attentional engagement bias to socially threatening stimuli is associated with a pattern of greater diurnal HPA axis reactivity across the first two days of the high school transition, as evidenced by a steeper cortisol awakening response and a steeper diurnal cortisol slope. This work extends our understanding of the mechanisms through which stress relates to wellbeing in youth by embedding biological development in the life course. Clinically, this work has the potential to inform interventions to protect youth against the biological embedding of stress by identifying a theoretically driven, socio-contextually relevant risk factor to be attenuated – namely, attentional bias to threat.

Elevated diurnal and evening salivary cortisol concentration are inversely correlated with outcomes related to sarcopenia in healthy older men

Elevated diurnal and evening salivary cortisol concentration are inversely correlated with outcomes related to sarcopenia in healthy older men

Increased nocturnal urinary cortisol levels in the elderly patients with depression, coexisting major geriatric syndromes and combined pathogenetic mechanisms

BackgroundThe mechanisms at the basis of depression are still matter of debate, but several studies in the literature suggest common pathways with dementia (genetic predispositions, metabolic and inflammatory mechanisms, neuropathological changes) and other geriatric syndromes.AimsTo evaluate the role of cortisol (as marker of the HPA, hypothalamus–pituitary–adrenal axis hyperactivity) in elderly subjects with depressive symptoms (by the means of the AGICO, AGIng and COrtisol, study), in relationship to the presence of the major geriatric syndromes.MethodsThe AGICO study enrolled patients from ten Geriatric Units in Italy. Every subject received a comprehensive geriatric assessment or CGA (including the Mini Mental State Examination or MMSE, Geriatric Depression Scale or GDS and Cornell Scale for Depression in Dementia or CSDD), the neurological examination (with a computed tomography scan or magnetic resonance imaging of the brain), the assessment of the metabolic syndrome (MetS), the evaluation of the cortisol activity by two consecutive urine collections (diurnal and nocturnal), a CGA-derived frailty index (FI) and a modified measure of allostatic load (AL).ResultsThe MMSE scores were significantly and inversely related to the values of GDS (p < 0.001) and CSDD (p < 0.05), respectively. The patients with depressive symptoms (GDS/CSDD > 8) showed significantly increased disability, MetS, inflammation, FI and AL and significantly reduced MMSE and renal function.The diurnal and nocturnal urinary cortisol levels in the patients with depressive symptoms (GDS/CSDD > 8) were higher with respects to controls (p < 0.05 for nocturnal difference).DiscussionThe AGICO study showed that the stress response is activated in the patients with depression.ConclusionThe depression in elderly patient should be reconsidered as a systemic disease, with coexisting major geriatric syndromes (disability, dementia, frailty) and combined pathogenetic mechanisms (metabolic syndrome, impaired renal function, low-grade inflammation, and allostatic load). Cortisol confirmed its role as principal mediator of the aging process in both dementia and metabolic syndrome.

Hatha yoga reduces momentary stress but does not impact diurnal profiles of salivary cortisol and alpha-amylase: A randomized controlled trial

Does the practice of yoga impact stress? Various studies have suggested that yoga may reduce both self-reported stress and stress biomarkers, but the evidence for such claims remains inconclusive, especially for yoga styles with a focus on physical postures. In a randomized controlled trial with 98 participants, we therefore examined whether an eight-week Hatha yoga intervention (60 min, 3×/week or more) led to reduced levels of diurnal salivary cortisol (sCort), salivary alpha-amylase (sAA), and subjective momentary stress as compared to a waitlist control group. To ensure the concomitant assessment of self-report and biological measures in an ecologically valid setting, and to capture the diurnal profile of cortisol and alpha-amylase, we employed an ecological momentary assessment approach. Five times per day, participants reported their momentary stress levels on a visual analogue scale and collected saliva samples for the assessment of salivary biomarkers. The intervention led to a significant reduction of subjective momentary stress but there was no change in diurnal sCort or sAA levels. There are several potential explanations for these findings: The intervention may have helped participants to cope better with stress while leaving diurnal levels of stress biomarkers unaffected, or the change may at least not have been reflected in sCort and sAA. Alternatively, there may have been a self-report bias, insofar as a favorable disposition towards yoga may have led participants to report reductions in stress in order to indicate positive effects of the intervention. Our findings contribute to a better understanding of the effects of distinct yoga interventions, demonstrating their potential to serve as low-risk stress relief tools.

Diurnal Cortisol Profiles Across Pregnancy: Challenges in the Current State of Knowledge

Diurnal Cortisol Profiles Across Pregnancy: Challenges in the Current State of Knowledge

Affective symptoms in pregnancy are associated with the vaginal microbiome

BackgroundComposition of the vaginal microbiome in pregnancy is associated with adverse maternal, obstetric, and child health outcomes. Therefore, identifying sources of individual differences in the vaginal microbiome is of considerable clinical and public health interest. The current study tested the hypothesis that vaginal microbiome composition during pregnancy is associated with an individual's experience of affective symptoms and stress exposure. MethodsData were based on a prospective longitudinal study of a medically healthy community sample of 275 mother-infant pairs. Affective symptoms and stress exposure and select measures of associated biomarkers (diurnal salivary cortisol, serum measures of sex hormones) were collected at each trimester; self-report, clinical, and medical records were used to collect detailed data on socio-demographic factors and health behavior, including diet and sleep. Vaginal microbiome samples were collected in the third trimester (34–40 weeks) and characterized by 16S rRNA sequencing. Identified taxa were clustered into three community clusters (CC1–3) based on dissimilarity of vaginal microbiota composition. ResultsResults indicate that depressive symptoms during pregnancy were reliably associated with individual taxa and CC3 in the third trimester. Prediction of functional potential from 16S taxonomy revealed a differential abundance of metabolic pathways in CC1–3 and individual taxa, including biosynthetic pathways for serotonin and dopamine. We did not find robust evidence linking symptom- and stress-related biomarkers and CCs. ConclusionsOur results provide further evidence of how prenatal psychological distress during pregnancy alters the maternal-fetal microbiome ecosystem that may be important for understanding maternal and child health outcomes.

Neuroinflammation, cerebrovascular dysfunction and diurnal cortisol biomarkers in a memory clinic cohort: Findings from the Co-STAR study

Cortisol dysregulation, neuroinflammation, and cerebrovascular dysfunction are biological processes that have been separately shown to be affected in Alzheimer’s disease (AD). Here, we aimed to identify biomarker signatures reflecting these pathways in 108 memory clinic patients with subjective cognitive decline (SCD, N = 40), mild cognitive impairment (MCI, N = 39), and AD (N = 29). Participants were from the well-characterized Cortisol and Stress in Alzheimer’s Disease (Co-STAR) cohort, recruited at Karolinska University Hospital. Salivary diurnal cortisol measures and 41 CSF proteins were analyzed. Principal component analysis was applied to identify combined biosignatures related to AD pathology, synaptic loss, and neuropsychological assessments, in linear regressions adjusted for confounders, such as age, sex, education and diagnosis. We found increased CSF levels of C-reactive protein (CRP), interferon γ-inducible protein (IP-10), thymus and activation-regulated chemokine (TARC), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) in MCI patients. Further, markers of cortisol dysregulation (flattened salivary cortisol awakening response and flattened cortisol slope) correlated with increased levels of placental growth factor (PlGF), IP-10, and chitinase 3-like 1 (YKL-40) in the total cohort. A biosignature composed of cortisol awakening response, cortisol slope, and CSF IL-6 was downregulated in AD patients. Moreover, biomarker signatures reflecting overlapping pathophysiological processes of neuroinflammation and vascular injury were associated with AD pathology, synaptic loss, and worsened processing speed. Our findings suggest an early dysregulation of immune and cerebrovascular processes during the MCI stage and provide insights into the interrelationship of chronic stress and neuroinflammation in AD.

Hypothalamic-pituitary-adrenal axis functioning in offspring of parents with a major affective disorder: a meta-analytic review.

Because the offspring of parents with an affective disorder (OAD) are at high risk for developing mental disorders, and persons with an affective disorder (AD) show dysfunctional hypothalamic-pituitary-adrenal (HPA) axis activity, changes in HPA functioning in OAD might be an etiological risk factor that precedes the development of ADs. The primary aim of the meta-analysis was to quantitatively summarize the existing data on different indices of diurnal cortisol in the OAD. The secondary aim was to explore potential moderators of this relation. Following PRISMA guidelines, we included 26 studies (3052 offspring) on diurnal cortisol in our meta-analysis after an initial screening of 3408 articles. Intercept-only and meta-regression models were computed using the robust variance estimation method. Analyses examining mean cortisol levels at discrete timepoints, total cortisol output, and the cortisol rise in response to awakening (CAR) were conducted separately. The results demonstrated that the OAD had higher mean levels of cortisol at different timepoints throughout the day compared to controls (Hedge's g = 0.21). There was evidence of publication bias in studies examining CAR, such that effect sizes were positively biased. The present findings are consistent with a meta-analysis showing elevated cortisol in youth having an AD. Notable limitations across studies include the method of cortisol measurement and assessment of ADs. Altogether, these results highlight the fact that increased cortisol levels may act as a potential neuroendocrine antecedent and/or risk factor for the development of ADs among high risk youth.

Differential increase of hippocampal subfield volume after socio-affective mental training relates to reductions in diurnal cortisol

The hippocampus is a central modulator of the HPA-axis, impacting the regulation of stress on brain structure, function, and behavior. The current study assessed whether three different types of 3 months mental Training Modules geared towards nurturing (a) attention-based mindfulness, (b) socio-affective, or (c) socio-cognitive skills may impact hippocampal organization by reducing stress. We evaluated mental training-induced changes in hippocampal subfield volume and intrinsic functional connectivity, by combining longitudinal structural and resting-state fMRI connectivity analysis in 332 healthy adults. We related these changes to changes in diurnal and chronic cortisol levels. We observed increases in bilateral cornu ammonis volume (CA1-3) following the 3 months compassion-based module targeting socio-affective skills (Affect module), as compared to socio-cognitive skills (Perspective module) or a waitlist cohort with no training intervention. Structural changes were paralleled by relative increases in functional connectivity of CA1-3 when fostering socio-affective as compared to socio-cognitive skills. Furthermore, training-induced changes in CA1-3 structure and function consistently correlated with reductions in cortisol output. Notably, using a multivariate approach, we found that other subfields that did not show group-level changes also contributed to changes in cortisol levels. Overall, we provide a link between a socio-emotional behavioural intervention, changes in hippocampal subfield structure and function, and reductions in cortisol in healthy adults.

Differential increase of hippocampal subfield volume after socio-affective mental training relates to reductions in diurnal cortisol.

The hippocampus is a central modulator of the HPA-axis, impacting the regulation of stress on brain structure, function, and behavior. The current study assessed whether three different types of 3 months mental Training Modules geared towards nurturing (a) attention-based mindfulness, (b) socio-affective, or (c) socio-cognitive skills may impact hippocampal organization by reducing stress. We evaluated mental training-induced changes in hippocampal subfield volume and intrinsic functional connectivity, by combining longitudinal structural and resting-state fMRI connectivity analysis in 332 healthy adults. We related these changes to changes in diurnal and chronic cortisol levels. We observed increases in bilateral cornu ammonis volume (CA1-3) following the 3 months compassion-based module targeting socio-affective skills (Affect module), as compared to socio-cognitive skills (Perspective module) or a waitlist cohort with no training intervention. Structural changes were paralleled by relative increases in functional connectivity of CA1-3 when fostering socio-affective as compared to socio-cognitive skills. Furthermore, training-induced changes in CA1-3 structure and function consistently correlated with reductions in cortisol output. Notably, using a multivariate approach, we found that other subfields that did not show group-level changes also contributed to changes in cortisol levels. Overall, we provide a link between a socio-emotional behavioural intervention, changes in hippocampal subfield structure and function, and reductions in cortisol in healthy adults.

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.

Prediction of suicidal thoughts and behaviors based on the diurnal cortisol pattern and THC dosage in continued cannabis users, a 5 year population-based matched cohort study

It appears that the THC dosage is the link between dysregulation of the hypothalamic pituitary adrenal (HPA) axis and suicidal thoughts and behaviors (STB). We proposed a new model to understand the underlying pathophysiological mechanism of STB based on the interaction of cortisol and THC dosage.From September 1, 2019, to January 1, 2024, we conducted a population-based, matched-pair, nested case-control study resulting from a three-wave complete longitudinal, multicenter cohort study on a sample of congress 60 clients. A total of 368 male continued cannabis users (CCu) were allocated to four categories, including low, moderate and high THC dosages and relapse, using optimal matching. Several HPA axis measures were analyzed in the saliva using liquid chromatography with tandem mass spectrometry (LC-MS-MS), and carboxylic acids levels in the urine were assessed via gas chromatography/mass spectrometry (GC–MS). We used structural equation modeling (SEM) to examine the relationship between the variables of interest and the model fit test, and used the Akaike information criterion (AIC) to compare the model fit and select the best-fitting model. Population attributable fractions (PAFs) and cumulative risk score were also calculated for the best-fitting pattern.The analysis showed that the likelihood of STB in individuals with a cortisol awakening response (CAR) and a blunted diurnal cortisol slope (DCS) and higher area under the curve (AUC) who reported heavy cannabis use was more than three times higher than the control group (OR 3.2, 95 % CI 2.4–4.1).These findings indicate the importance of the specific cortisol secretion pattern in the increased clinical expression of STB and may be an important factor for guiding preventive efforts in this area.

Self-Compassion is Associated with Improved Well-Being and Healthier Cortisol Profiles in Undergraduate Students

ObjectivesStress is highly prevalent in college students. Self-compassion, the tendency to respond in a caring manner to one’s own suffering or failures, reduces psychological distress and promotes mental health. Self-compassion may also influence physiological manifestations of stress; however, research is limited. Among undergraduate students over the course of an academic semester, we explored the associations of self-compassion with stress-related psychological variables including measures of affect, anxiety, and depressive symptoms. We also examined daily patterns of salivary cortisol over four days: diurnal slope, mean, and day-to-day cortisol rhythm stability.MethodThis sample of undergraduate students from introductory psychology courses in a large United States Midwestern university was predominantly non-Hispanic White (71.2%) and female (86.4%). All data were collected prior to final exams. After providing baseline psychosocial data, participants engaged in a 2-week mindfulness intervention: They were provided an iPod loaded with audio tracks based on the well-known Mindfulness-Based Stress Reduction intervention, but received no face-to-face instruction. Fifty-nine participants provided self-report demographic and medical data and completed the saliva sampling regimen over the first 4 days of the intervention. Diurnal salivary cortisol was assessed immediately after waking and again at bedtime over four consecutive days.ResultsHierarchical multiple regressions replicated previous findings showing that self-compassion is associated with higher positive and lower negative affect, lower perceived stress, and fewer symptoms of anxiety and depression. Regression models controlling for oral contraception and tobacco use revealed a positive association of self-compassion with healthy cortisol profiles marked by steeper diurnal cortisol slopes and increased regularity of the inter-daily cortisol slope.ConclusionsThese results confirm that self-compassion may be protective against the psychological and physiological manifestations of stress in college. Kind and compassionate responses to one’s own struggles may shield students from the adverse effects of stress. The potential mechanisms underlying these associations are worthy of future research.PreregistrationThis study is not preregistered.

Association Between Dietary Quality and Diurnal Salivary Cortisol in Hispanics/Latinos at Risk for Alzheimer’s Disease

Association Between Dietary Quality and Diurnal Salivary Cortisol in Hispanics/Latinos at Risk for Alzheimer’s Disease

Sleep, Health Outcomes and Body Weight (SHOW) study: a measurement burst design study on sleep and risk factors for obesity in black emerging adults in North Carolina, USA

IntroductionBlack emerging adults (18–28 years) have the highest risk of short sleep duration and obesity. This increased risk may be partly explained by greater stress levels, which may result from...

“What’s yours is mine”: Partners’ everyday emotional experiences and cortisol in older adult couples

The existing literature consistently finds that emotional experiences and cortisol secretion are linked at the within-person level. Further, relationship partners tend to covary in emotional experience, and in cortisol secretion. However, we are only beginning to understand whether and how an individuals’ emotions are linked to their relationship partners’ cortisol secretion. In this project, we harmonized data from three intensive measurement studies originating from Canada and Germany to investigate the daily dynamics of emotions and cortisol within 321 older adult couples (age range=56–87 years). Three-level multilevel models accounted for the nested structure of the data (repeated assessments within individuals within couples). Actor-Partner Interdependence Models were used to examine the effect of own emotional experiences (actor effects) and partner emotional experiences (partner effects) on momentary and daily cortisol secretion. Adjusting for age, sex, education, comorbidities, assay version, diurnal cortisol rhythm, time spent together, medication, and time-varying behaviors that may increase cortisol secretion, results suggest that higher relationship partner’s positive emotions are linked with lower momentary cortisol and total daily cortisol. Further, this association was stronger for older participants and those who reported higher relationship satisfaction. We did not find within-couple links between negative emotions and cortisol. Overall, our results suggest that one’s relationship partner’s positive emotional experience may be a protective factor for their physiological responding, and that these more fleeting and day-to-day fluctuations may accumulate over time, contributing to overall relationship satisfaction.