Hair glucocorticoids in adults with intellectual disabilities and depressive symptoms pre- and post-bright light therapy: First explorations

J Appl Res Intellect Disabil. 2021 Nov;34(6):1549-1559. doi: 10.1111/jar.12899. Epub 2021 May 28.


Background: Depressive symptoms and stress are common in adults with intellectual disabilities. Our aim was to explore long-term biological stress levels, assessed by hair cortisol (HairF) and cortisone (HairE) concentrations, in adults with intellectual disabilities and depressive symptoms and to investigate the effects of bright light therapy (BLT) on hair glucocorticoids.

Method: Scalp hair samples (n = 14) were retrospectively examined at baseline and post-BLT (10.000 and 300 lux). Liquid chromatography-tandem mass spectrometry was used to measure hair glucocorticoids.

Results: A significant correlation was found between baseline HairF and depression scores (r = .605, p = .028). Post-intervention HairE levels were significantly increased ([95% CI: 11.2-17.4 pg/mg], p = .003), in particular after dim light (300 lux) ([95% CI: 10.0-18.3 pg/mg], p = .020).

Conclusions: This study showed that retrospectively examining biological levels of stress in adults with intellectual disabilities seems a potentially promising and objective method to gain insight in the stress level of adults with intellectual disabilities.

Keywords: bright light therapy; cortisol; cortisone; depression; intellectual disabilities; long-term stress.

MeSH terms

  • Adult
  • Depression
  • Glucocorticoids*
  • Humans
  • Intellectual Disability*
  • Phototherapy
  • Retrospective Studies


  • Glucocorticoids