Hair cortisol and dehydroepiandrosterone and their associations with optimism and pessimism in older people.

The cumulative negative effects of prolonged Hypothalamic-Pituitary-Adrenal axis (HPA axis) activation are associated with several age-related diseases. Some psychological traits such as optimism and pessimism have been shown to be related to both health and the stress response, although their relationship with the HPA axis is inconclusive. More stable HPA axis biomarkers, such as hair samples of cortisol (HC) and dehydroepiandrosterone (HDHEA), would help to clarify the association between these psychological traits and HPA axis functioning. The main aim of this study was to test the relationships between optimism and pessimism and chronic stress biomarkers measured in hair (HC and HDHEA). Additionally, a secondary objective was to explore sex differences in HC and HDHEA levels and their relationship with these psychological traits. We measured optimism, pessimism, and their combination (dispositional optimism) using the Life Orientation Test Revised (LOT-R) and chronic stress biomarkers (HC and HDHEA) in 119 healthy participants (46 men and 73 women) between 56 and 81 years old who belonged to a university program. Regression analyses controlling for perceived stress and BMI indicated that higher dispositional optimism was related to lower HC and HC:HDHEAratio (ß = -0.256, p = .008 and ß = -0.300, p = .002, respectively). More specifically, higher pessimism was related to higher HC (ß = 0.235; p = .012) and HC:HDHEAratio (ß = 0.240; p = .011), whereas higher optimism was associated with a lower HC:HDHEAratio(ß = -0.205; p = .031). Moderation analyses showed no sex differences. To date, this is the first study to investigate the link between these traits and HC and HDHEA in older people. Our results confirm that positive and negative expectations about the future (i.e. optimism and pessimism) may play an important role in health due to their relationship with the HPA axis. They also strengthen the idea that the negative effects of pessimism have a greater weight than the protective effects of optimism in their relationship with HPA axis regulation.

HOME vs. LAB hair samples for the determination of long-term steroid concentrations: a comparison between hair samples collected by laypersons and trained research staff.

Hair segment analysis is a valuable tool for the assessment of cumulative long-term steroid secretion. Preliminary findings suggest comparable cortisol concentrations in hair collected by instructed laypersons and research staff. However, it remains unclear whether hair sample quality and hair steroids other than cortisol are affected by level of experience (laypersons vs. research staff), home collection circumstances (instructions, familiarity to participant, performance confidence), and characteristics of the layperson (conscientiousness). Sixty participants (23.6 ± 3.9 years; 43 females) provided hair samples twice: first collected by laypersons (HOME) according to provided instructions (written vs. written/video-based instructions) and second by trained research staff (LAB) on the same day or the day after the HOME collection. Hair steroid concentrations (cortisol, cortisone, DHEA, progesterone) were determined using LC-MS/MS. Hair sample quality was evaluated using nine predefined criteria. Laypersons completed questionnaires for the assessment of potential factors of hair outcome measures (hair steroid concentrations, hair sample quality). Hair steroids from HOME and LAB samples were positively correlated (rs between 0.76 and 0.89) and did not significantly differ, with the exception of cortisone. The quality of hair samples was significantly higher for LAB than for HOME samples. Neither HOME collection circumstances nor layperson-related characteristics had an impact on hair outcome measures. However, a low self-reported performance confidence predicted a high absolute difference between HOME and LAB DHEA. In summary, our findings suggest higher quality of hair samples collected by trained research staff compared to instructed laypersons. However, these differences might be negligible, considering the high correlation between HOME and LAB hair steroid concentrations, with the characteristics of the layperson or collection circumstances having a minor impact on hair steroids and hair sample quality. These findings provide further support for the notion that well-instructed laypersons can be enabled to collect hair samples.

Assay validation of hair androgens across the menstrual cycle.

INTRODUCTION: Saliva is a common noninvasive biofluid for measuring stress and sex hormones, yet one pressing limitation is that salivary hormones fluctuate momentarily, daily, and (for girls) across the menstrual cycle. Hair steroid assays are thought to provide a cumulative index which collapses across hormonal variability, potentially eliminating the confound of daily and menstrual cyclicity and thereby reflecting individual differences in average hormone levels. Here we seek to validate a hair bioassay methodology and test whether hair androgens accurately measure long-term, stable androgen levels in emerging adult women across two menstrual cycles. METHODS: Hair samples were collected at the end of each menstrual cycle for two cycles, and saliva samples were collected in the morning once per week across two menstrual cycles (N = 11 women). Hair samples were segmented by 1 cm for the first 4 cm to reflect the hormone levels of the past four serial months. Hair samples were assayed using commercially-available enzyme-immuno-assays for testosterone and DHEA. RESULTS: Hair androgen concentrations were significantly correlated with averaged saliva hormone levels (DHEA: r = .75, p < .05; Testosterone: r = .67, p < .05). With respect to hair hormone stability, there were significant correlations for almost all the pairs of two 1 cm hair segments collected in two months that corresponded to the same time period. Hair androgens in one segment were significantly correlated with those in next segment. Regarding salivary androgen stability, the intra-class correlation across the weekly saliva samples indicated that for DHEA 59% of the total variance was within person and 41% was between person; and for testosterone 91% of the total variance was between person, and only 9% within person. DISCUSSION: Results suggest that a one-time measure of hair provides a valid and reliable estimate of average steroid levels across two months. Moreover, whereas saliva measures of androgen levels capture week-to-week fluctuations in steroids, hair samples provide information on individual differences in average exposure to steroids, across long periods of time, such as months. Results are encouraging that hair DHEA and testosterone reflects the cumulative hormonal concentration and can be used as a stable hormonal index. Results also indicate that it is feasible to collect the first 3-4 centimeters of hair for studies of stable hormone levels.

Hair cortisol concentration and glycated hemoglobin in African American adults.

BACKGROUND: African Americans have higher diabetes prevalence compared to Whites. They also have elevated cortisol levels - indicating possible HPA axis dysregulation - which may raise blood glucose as part of the biological response to physiological and psychosocial stress. Little is known about chronic cortisol levels in African Americans, and even less about the role of chronically elevated cortisol in type 2 diabetes development in this racial group. PURPOSE: We used analysis of cortisol in hair to examine associations of long-term (∼3months) cortisol levels with glycated hemoglobin (HbA1c) in a group of African American adults. In exploratory analyses, we also studied the relationship of hair dehydroepiandrosterone (DHEA) with HbA1c. METHOD: Participants were 61 community-dwelling African American adults (85% female; mean age 54.30 years). The first 3cm of scalp-near hair were analyzed for cortisol and DHEA concentration using enzyme-linked immunoassay analysis. Glycated hemoglobin was assessed, and regression analyses predicting HbA1c from hair cortisol and DHEA were performed in the full sample and in a subsample of participants (n=20) meeting the National Institute of Diabetes and Digestive Kidney Disease (NIDDK) criteria for type 2 diabetes (HbA1c≥6.5%). RESULTS: In the full sample, HbA1c increased with hair cortisol level (ß=0.22, p=0.04, f(2)=0.10), independent of age, sex, chronic health conditions, diabetes medication use, exercise, and depressive symptoms. In the subsample of participants with an HbA1c≥6.5%, hair cortisol was also positively related to HbA1c (ß=0.45, p=0.04, f(2)=0.32), independent of diabetes medication use. Glycated hemoglobin was unrelated to hair DHEA in both the full sample and HbA1c≥6.5% subsample. CONCLUSION: Long-term HPA axis dysregulation in the form of elevated hair cortisol is associated with elevated HbA1c in African American adults.