Measurement of cortisol in human Hair as a biomarker of systemic exposure

Abstract

Clin Invest Med 2007; 30 (5): E183-E191. AbstractPurpose: Current methods for measuring long-term endogenous production of cortisol can be challenging due to the need to take multiple urine, saliva or serum samples. Hair grows approximately 1 centimeter per month, and hair analysis accurately reflects exposure to drug abuse and environmental toxins. Here we describe a new assay for measurement of cortisol in hair, and determined a reference range for non-obese subjects. Methods: For measurement of cortisol in hair we modified an immunoassay originally developed for measuring cortisol in saliva. We compared hair samples obtained from various parts of the head, and assessed the effect of hair dying. We analyzed hair samples from non-obese subjects, in whom we also obtained urine, saliva and blood samples for cortisol measurements. Results: The mean extraction recovery for hair cortisol standards of 100 ng/ml, 50 ng/ml and 2 ng/ml (n=6) was 87.9%, 88.9% and 87.4%, respectively. Hair cortisol levels were not affected by hair color or by dying hair samples after they were obtained. Cortisol levels were decreased in hair that was artificially colored before taking the sample. The coefficient of variation was high for cortisol levels in hair from different sections of the head (30.5%), but was smaller when comparing between hair samples obtained from the vertex posterior (15.6%). The reference range for cortisol in hair was 17.7-153.2 pg/mg of hair (median 46.1 pg/mg). Hair cortisol levels correlated significantly with cortisol in 24-hour urine (r=0.33; P=0.041). Conclusion:The correlation of hair cortisol with 24-hour urine cortisol supports its relevance as biomarker for longterm exposure.Cortisol is a glucocorticoid hormone produced by the adrenal glands. In humans, cortisol levels are increased in severe stress, depression, and selected systemic diseases such as Cushing's syndrome. Proper assessment of endogenous cortisol secretion is required to adequately determine its relation to these clinical conditions. For that end, cortisol is currently measured in saliva, serum and urine. While each of these measurements has advantages and limitations, all these methods require multiple samples to provide an assessment of cortisol levels over prolonged periods of time. Furthermore, due to diurnal variations

Extraction and Analysis of Cortisol from Human and Monkey Hair

“…The exception is a grinding apparatus such as a ball mill or mini-beadbeater. We note that some research groups mince hair samples into small fragments roughly 1 mm in length 12 , but based on our observations we recommend performing grinding instead of mincing if at all possible. Another area of methodological variation in the literature involves whether or not to wash the hair prior to CORT extraction 13 , and if so, what wash conditions to use.…”

Relationship between hair and salivary cortisol and pregnancy in women undergoing IVF

“…The validity and reliability of hair cortisol sampling has been supported in both animal (Davenport et al, 2006) and human studies (Sauve et al, 2007;Stalder and Kirschbaum, 2012). Furthermore, the utility of hair sampling as a marker of long term HPA function has been demonstrated in a range of health contexts (Yamada et al, 2007;Kalra et al, 2007;Dettenborn et al, 2011;Steudte et al, 2011;Pereg et al, 2011;Braig et al, 2015).…”

Hypothalamic-pituitary-adrenal axis dysregulation and cortisol activity in obesity: A systematic review

“…As hair grows approximately one centimeter each month, hair cortisol measurements reflect cortisol concentrations over an extended period of time, rather than one day, and there is evidence that this measure is correlated with 24-h UFC (Sauvé et al, 2007). …”

“…This may be because urinary cortisol reflects total cortisol secreted whereas salivary cortisol reflects free cortisol already filtered from plasma, thus already accounting for clearance. Finally, while these methods index patterns of daily cortisol concentrations, hair can be used to measure long-term systemic cortisol output and has been shown to correlate with 24-h urinary free cortisol (UFC; Sauvé et al, 2007).…”