Associations of psychoactive substances and steroid hormones in hair: Findings relevant to stress research from a large cohort of young adults

Abstract

Objective:
Epidemiological studies increasingly use hair samples to assess people’s cumulative exposure to steroid
hormones, but how the use of different psychoactive substances may affect steroid hormone levels in hair is, so
far, largely unknown. The current study addresses this gap by establishing the substance exposure correlates of
cortisol, cortisone, and testosterone in hair, while also accounting for a number of relevant covariates.

Method:
Data came from a large urban community-sample of young adults with a high prevalence of substance
use (N = 1002, mean age=20.6 years, 50.2% female), who provided 3 cm of hair samples. Liquid
chromatography-tandem mass spectrometry (LC-MS/MS) quantified cortisol, cortisone, and testosterone, as well
as delta-9-tetrahydrocannabinol (THC), 3,4-methylenedioxymethamphetamine (MDMA, “Ecstasy”), cocaine,
several opioids, and their respective metabolites. Multiple linear regression models with covariates were used to
predict steroid hormone levels from substance exposure in a four-step approach: In the full sample, low and high
substance hair concentrations (median split) were first tested against no use for each substance individually (step
1) and for all substances together (step 2). Then, within the participants with any substance in hair only, the
continuous hair concentration of each substance in pg/mg (step 3) and finally of all substances together, were
regressed (step 4).

Results:
Low, high, and continuous levels of THC in hair were robustly associated with higher levels of cortisol
(sig. in step 1 low THC: β = 0.29, p = .021; high THC: β = 0.42, p = .001; step 2: low THC: β = 0.27, p = 0.036,
and high THC: β = 0.40, p = .004, and step 4: β = 0.12, p = .041). Participants with high MDMA levels had
higher levels of cortisone without adjusting for other substances (step 1: β = 0.34, p = .026), but this effect was
not significant in the other models. While high THC levels were associated with lower levels of testosterone in
step 2 (β = -0.35, p = .018), MDMA concentration was positively related to testosterone concentration with and
without adjusting for other substances (step 3: β = 0.24, p = .041; step 4: β = 0.17, 95%, p = .015) in male
participants.

Conclusion:
The use of psychoactive substances, especially of cannabis and ecstasy, should be considered in
studies investigating steroid hormones in hair.