Assessment of the cortisol awakening response: expert consensus guidelines

The cortisol awakening response (CAR), the marked increase in cortisol secretion over the first 30–45 min after morning awakening, has been related to a wide range of psychosocial, physical and mental health parameters, making it a key variable for psychoneuroendocrinological research. The CAR is typically assessed from self-collection of saliva samples within the domestic setting. While this confers ecological validity, it lacks direct researcher oversight which can be problematic as the validity of CAR measurement critically relies on participants closely following a timed sampling schedule, beginning with the moment of awakening. Researchers assessing the CAR thus need to take important steps to maximize and monitor saliva sampling accuracy as well as consider a range of other relevant methodological factors. To promote best practice of future research in this field, the International Society of Psychoneuroendocrinology initiated an expert panel charged with (i) summarizing relevant evidence and collective experience on methodological factors affecting CAR assessment and (ii) formulating clear consensus guidelines for future research. The present report summarizes the results of this undertaking. Consensus guidelines are presented on central aspects of CAR assessment, including objective control of sampling accuracy/adherence, participant instructions, covariate accounting, sampling protocols, quantification strategies as well as reporting and interpreting of CAR data. Meeting these methodological standards in future research will create more powerful research designs, thus yielding more reliable and reproducible results and helping to further advance understanding in this evolving field of research

An 8-week relaxation program consisting of progressive muscle relaxation and mindfulness meditation to reduce stress and attenuate stress-driven eating

Background: Stress is often associated with the intake of energy-dense palatable foods. This trial examined the feasibility and preliminary efficacy of an 8-week worksite-based relaxation intervention to address psychological stress and unhealthy food intake. Methods: Thirty-six men and women were exposed to an acute stressor, while physiological and psychological responses were assessed, prior to being offered a test meal. Participants were then randomised to a relaxation intervention (RELAX; face-to-face classes and daily home practice of progressive muscle relaxation and mindfulness meditation), or a wait-list control (CON). All measures were repeated after the intervention. Results: Intervention compliance was high (80% ± 19% face-to-face; 79% ± 18% home practice), and each session acutely reduced perceived stress (p <.001) and increased relaxation (p <.001). After 8 weeks, trait mindfulness was increased (p =.025), along with reduced tension (p =.013) and increased relaxation (p <.05) post-acute stressor in the intervention group. There was no effect of the intervention on palatable eating, cravings, or energy intake at a laboratory test meal, with small associated effect sizes (d = 0.01–0.3). Conclusions: The program studied here is feasible and sessions transiently reduce perceived stress and improve mindfulness; however, the program may not influence the physiological response to an acute stressor or appetite and eating variables

Human mineralocorticoid receptor (MR) gene haplotypes modulate MR expression and transactivation: implication for the stress response

Stress causes activation of the hypothalamic-pituitary-adrenal (HPA) axis, resulting in secretion of corticosteroids which facilitate behavioural adaptation. These effects exerted by corticosteroids are mediated by two brain corticosteroid receptor types, the mineralocorticoid receptor (MR), with a high affinity already occupied under basal conditions and the glucocorticoid receptor (GR), with a low affinity only activated during stress. Here, we studied MR gene haplotypes constituted by the two single nucleotide polymorphisms MR-2G/C (rs2070951) and MRI180V (rs5522). The haplotypes showed differences in cortisol-induced gene transcription and protein expression while the structural variant MRI180V did not affect ligand binding. Moreover, in a well characterized cohort of 166 school teachers these haplotypes have been associated with perceived chronic stress (Trier Inventory for the Assessment of Chronic Stress, TICS) and, in a subgroup of 47 subjects, with ACTH, cortisol and heart rate responses to acute psychosocial stress (Trier Social Stress Test, TSST). MR haplotypes were significantly associated with the TICS scales "excessive demands at work" and "social overload". Subjects homozygous for haplotype MR-2C/MRI180, which in vitro showed highest expression and transactivational activity, displayed the highest salivary cortisol (p<0.001), plasma cortisol (p=0.010), plasma ACTH (p=0.003) and heart rate (p=0.018) responses. It is concluded that the investigated MR haplotypes modulate cortisol-induced gene transcription in vitro. Moreover, these haplotypes may contribute to individual differences in perceived chronic stress as well as neuroendocrine and cardiovascular stress responses.Stress-related psychiatric disorders across the life spa