Sexual orientation modulates endocrine stress reactivity

Biol Psychiatry. 2015 Apr 1;77(7):668-76. doi: 10.1016/j.biopsych.2014.08.013. Epub 2014 Aug 26.

Abstract

Background: Biological sex differences and sociocultural gender diversity influence endocrine stress reactivity. Although numerous studies have shown that men typically activate stronger stress responses than women when exposed to laboratory-based psychosocial stressors, it is unclear whether sexual orientation further modulates stress reactivity. Given that lesbian, gay, and bisexual (LGB) individuals frequently report heightened distress secondary to stigma-related stressors, we investigated whether cortisol stress reactivity differs between LGB individuals and heterosexual individuals in response to a well-validated psychosocial stressor.

Methods: The study population comprised 87 healthy adults (mean age, 25 years) who were grouped according to their biological sex and their gendered sexual orientation: lesbian/bisexual women (n = 20), heterosexual women (n = 21), gay/bisexual men (n = 26), and heterosexual men (n = 20). Investigators collected 10 salivary cortisol samples throughout a 2-hour afternoon visit involving exposure to the Trier Social Stress Test modified to maximize between-sex differences.

Results: Relative to heterosexual women, lesbian/bisexual women showed higher cortisol stress reactivity 40 min after exposure to the stressor. In contrast, gay/bisexual men displayed lower overall cortisol concentrations throughout testing compared with heterosexual men. Main findings were significant while adjusting for sex hormones (estradiol-to-progesterone ratio in women and testosterone in men), age, self-esteem, and disclosure status (whether LGB participants had completed their "coming out").

Conclusions: Our results provide novel evidence for gender-based modulation of cortisol stress reactivity based on sexual orientation that goes beyond well-established between-sex differences. This study raises several important avenues for future research related to the physiologic functioning of LGB populations and gender diversity more broadly.

Keywords: Cortisol; Gender diversity; Sex differences; Sexual orientation; Stress reactivity; Trier Social Stress Test.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aging / metabolism
  • Bisexuality / physiology*
  • Estradiol / metabolism
  • Female
  • Heterosexuality / physiology*
  • Homosexuality, Female*
  • Homosexuality, Male*
  • Humans
  • Hydrocortisone / metabolism*
  • Male
  • Progesterone / metabolism
  • Saliva / metabolism
  • Self Concept
  • Sex Characteristics
  • Stress, Psychological / metabolism*
  • Stress, Psychological / psychology
  • Testosterone / metabolism
  • Young Adult

Substances

  • Testosterone
  • Progesterone
  • Estradiol
  • Hydrocortisone