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

Glucocorticoid receptor gene polymorphisms and glucocorticoid sensitivity of subdermal blood vessels and leukocytes

A considerable variability in the sensitivity to glucocorticoids (GCs) exists between individuals and these differences have been implicated in the etiology of psychiatric diseases such as depression. Glucocorticoid receptor (GR) gene polymorphisms might account in part for variability in GC responsiveness. We assessed the association between four common GR gene (NR3C1) polymorphisms (ER22/23EK, N363S, BclI, 9beta) and markers of glucocorticoid sensitivity in two target tissues (subdermal blood vessels, peripheral leukocytes) in 206 healthy individuals. The BclI GG genotype group showed the least degree of skin blanching, reflecting a lower GC sensitivity of subdermal blood vessels (p = .01). No association between GR genotype and GC sensitivity of peripheral leukocytes was observed. In the same subjects we previously observed an association between GR genotype and GC sensitivity of the pituitary. Polymorphism of the GR gene might constitute a vulnerability or protection factor for stress related disorders and altered GC sensitivity

Working memory performance is associated with common glucocorticoid receptor gene polymorphisms

Cortisol has a modulatory influence on cognitive functions in humans. Both impairing and enhancing effects of cortisol administration have been shown for hippocampus dependent declarative memory and impairing effects have been shown for prefrontal cortex dependent working memory function. Given the high density of glucocorticoid receptors in the prefrontal cortex, we investigated whether common polymorphisms of the glucocorticoid receptor gene (ER22/23EK, N363S, BclI, 9beta A3669G) modulate the influence of cortisol administration on working memory. Working memory performance was investigated in 169 subjects under 10mg hydrocortisone (cortisol) and under placebo using an item-recognition task. No impairing effect of hydrocortisone treatment became evident. However, a sex by genotype interaction on general working memory performance was revealed (p=.02). While female heterozygous carriers of the 9beta G allele displayed faster reaction times than the other genotype groups, 9beta G heterozygous men were relatively slower. Heritability estimates for memory are roughly 50%, indicating that common genetic polymorphisms have an important impact on cognitive performance. Our results suggest that variants of the GR gene might explain some of the variance attributable to genetic factors. Furthermore, it can be speculated that they modulate the individual vulnerability for memory impairments related to stress related psychiatric disorder

Evidence for an association between mineralocorticoid receptor gene haplotypes and psychobiological measures of atypical depression

Diabetes mellitus: pathophysiological changes and therap

A psychobiological perspective on genetic determinants of hypothalamus-pituitary-adrenal axis activity

From the perspective of psychobiological stress research we present a brief overview of findings documenting a significant impact of genetic factors on the activity of the hypothalamus-pituitary-adrenal (HPA) axis. Quantitative genetic studies in twins as well as association studies, primarily on polymorphisms in the glucocorticoid receptor gene, are depicted. Recent findings suggest that the collaboration of psychobiology and molecular genetics is a promising interdisciplinary approach that will significantly contribute to the understanding of the mechanisms underlying the link between stress, the HPA axis, and HPA-related clinical states