Evaluation of a method to measure long term cortisol levels

Area of Science:

• Endocrinology
• Biochemistry
• Clinical Diagnostics

Background:

• Elevated cortisol is linked to obesity, diabetes, osteoporosis, and cardiovascular disease.
• Traditional cortisol measurements (serum, saliva, urine) offer only a single time point.
• Hair cortisol analysis provides a novel method for assessing long-term cortisol exposure.

Purpose of the Study:

• To evaluate the feasibility of hair cortisol as a parameter for measuring cortisol exposure.
• To investigate the correlation between hair cortisol levels and anthropometric/clinical markers.

Main Methods:

• Hair samples from 195 healthy individuals and 10 patients (9 hypercortisolemic, 1 hypocortisolemic) were analyzed for cortisol.
• Cortisol was extracted using methanol and quantified via ELISA.
• Waist circumference, hip circumference, and blood pressure were measured in 46 healthy subjects.

Main Results:

• Hair cortisol showed a positive correlation with waist circumference (r=0.392) and waist-to-hip ratio (WHR) (r=0.425).
• No significant correlations were found between hair cortisol and BMI, blood pressure, or age.
• Hair cortisol levels were significantly elevated in hypercortisolemic patients (p<0.0001).

Conclusions:

• Hair cortisol is a feasible marker reflecting cortisol exposure at the tissue level.
• Positive correlations with WHR and elevated levels in hypercortisolism support its clinical utility.
• Hair cortisol measurements are minimally affected by hair treatments, color, products, gender, or age.