Measuring cortisol and DHEA in fingernails: a pilot study

Area of Science:

• Endocrinology
• Psychoneuroendocrinology
• Biomarker Discovery

Background:

• Cortisol and dehydroepiandrosterone (DHEA) abnormalities are linked to psychiatric disorders.
• Conventional hormone level analysis (saliva, urine, blood) offers short-term insights.
• Fingernails passively incorporate endogenous hormones during keratinization, reflecting prolonged secretion.

Purpose of the Study:

• To pilot the measurement of cortisol and DHEA levels in fingernails.
• To assess fingernail hormone levels as a potential indicator of accumulated steroid hormone secretion over extended periods.
• To explore a novel method for assessing long-term hormonal changes relevant to psychiatric research.

Main Methods:

• Collected fingernail samples from 33 university students (18-24 years) twice during a semester.
• Scheduled sample collection to capture periods of varying student stress levels.
• Analyzed nail cortisol and dehydroepiandrosterone (DHEA) levels.

Main Results:

• A significant increase in the cortisol:DHEA ratio was observed during periods of higher stress (P = 0.0002).
• This ratio increase was driven by a significant decrease in DHEA levels (P = 0.004).
• Cortisol levels showed a numerical increase, though not statistically significant (P = 0.256).

Conclusions:

• Fingernail analysis is a viable method for measuring cortisol and DHEA.
• This technique may serve as a biomarker for environmental stress.
• Further validation is needed, but this method holds promise for studying healthy and patient populations.