Investigating relations among stress, sleep and nail cortisol and DHEA

Abstract

In the current study, we present data investigating the relationships among stress, sleep disturbance, self-control, and levels of cortisol (CORT) and dehydroepiandrosterone (DHEA) in fingernail clippings. Currently, hair CORT is the only routinely used noninvasive, validated, biomarker of chronic exposure to stress-related hormones. Nail clippings represent an important potential alternative sample matrix for assessing chronic hormone exposure, as it offers a different timeline of hormone incorporation than scalp hair, and may be obtainable from populations in which hair either is lacking or is unavailable for cultural reasons. Moreover, there is established precedent for using fingernail clippings to attain biomarker data. However, the value of nail hormone assessment for psychological research is currently unknown due to a paucity of information on the relations between nail hormone concentrations and environmental or psychological variables. In the present study, we collected data from a low income, minority population (N = 47; 97% African American) to demonstrate feasibility and acceptability of nail collection and analysis of the adrenal steroids CORT and DHEA. Participants reported on perceived stress, sleep and self-control abilities. Correlational analyses suggest that exposure to stressful events, disturbances in sleep and waking were associated with higher levels of nail DHEA, while self-control was associated with higher levels of nail CORT. We discuss the potential importance of this methodology for investigating biological, behavioral, and subjective indices of stress and well-being.

Innovations in biological assessments of chronic stress through hair and nail cortisol: Conceptual, developmental, and methodological issues

“…Among infants, nail DHEA was positively associated with prenatal stress in the first trimester, with nail DHEA positively associated with infant irritability (Mikoteit et al, ). Nail DHEA in the previously mentioned study on low‐income minority adolescents was also shown to be positively associated with stressful events, sleep disturbance, and waking (Doan et al, ). In another study with 33 university students, an increase in the ratio between nail cortisol and nail DHEA was observed during a stressful period in the semester.…”

“…As noted, there has been very little characterization of the contexts among studies using hair or nail cortisol, with studies mostly relying on simple measures of socioeconomic status. For instance, only a few hair cortisol studies have made minority and low‐income children and families a focus of study (Doan et al, ; Liu et al, ; Rippe et al, ; Vaghri et al, ). Given the very little variation in context among most studies, there remains a limited understanding regarding the influence of context on hair and nail cortisol across development.…”

“…While hair cut from the root indexes the recent past (depending on how much hair is cut), nails that are available to be cut are actually indexing several months past the time the nail emerges from the matrix. Thus, it may make more sense to collect data on potential causes of cortisol (e.g., stressful events) and wait a few months before collecting nail samples (Doan et al, ). Overall, there may be some imprecision in the time frame of the cortisol output being assessed when using hair and nail cortisol; accordingly, the measures would not be well suited for studies that aiming to detect change by the day.…”

“…To our knowledge, a few studies have been conducted to examine nail cortisol in children. In a study we conducted with 46 mostly low‐income minority adolescents, nail cortisol was not associated with perceived stress but instead was positively associated with self‐regulation as assessed by effortful control (Doan, Deyoung, Fuller‐Rowell, Liu, & Meyer, ).…”

<p>Correlation of selected stress associated factors with vitamin D deficiency in Jordanian men and women</p>

“…Allostatic load is an inability of the body's systems to accommodate adequately stress challenge due to chronic stressThis accompanies the modern lifestyle and impairs normal levels of stress mediators including cortisol (CORT). 4 Therefore elevated CORT levels reflect decreased body's ability to counteract consequences of chronic stress, 5,6 and to support quality of life. 7 Accordingly, fluctuating blood levels of CORT have been correlated with certain individual's behaviors such as heavy cigarettes smoking, 8 heavy coffee consumption, 9 sleep deprivation, 10 overweight, 11,12 and hyperlipidemaia.…”