Early endocrine alterations reflect prolonged stress and relate to 1-year functional outcome in patients with severe brain injury

Eur J Endocrinol. 2015 Jun;172(6):813-22. doi: 10.1530/EJE-14-1152. Epub 2015 Mar 30.

Abstract

Objective: Severe brain injury may increase the risk of developing acute and chronic hypopituitarism. Pituitary hormone alterations developed in the early recovery phase after brain injury may have implications for long-term functional recovery. The objective of the present study was to assess the pattern and prevalence of pituitary hormone alterations 3 months after a severe brain injury with relation to functional outcome at a 1-year follow-up.

Design: Prospective study at a tertiary university referral centre.

Methods: A total of 163 patients admitted to neurorehabilitation after severe traumatic brain injury (TBI, n=111) or non-TBI (n=52) were included. The main outcome measures were endocrine alterations 3.3 months (median) after the brain injury and their relationship to the functioning and ability of the patients at a 1-year follow-up, as measured by the Functional Independence Measure and the Glasgow Outcome Scale-Extended.

Results: Three months after the injury, elevated stress hormones (i.e. 30 min stimulated cortisol, prolactin and/or IGF1) and/or suppressed gonadal or thyroid hormones were recorded in 68 and 32% of the patients respectively. At 1 year after the injury, lower functioning level (Functional Independence Measure) and lower capability of performing normal life activities (Glasgow Outcome Scale-Extended) were related to both the elevated stress hormones (P≤0.01) and the reduced gonadal and/or thyroid hormones (P≤0.01) measured at 3 months.

Conclusion: The present study suggests that brain injury-related endocrine alterations that mimic secondary hypogonadism and hypothyroidism and that occur with elevated stress hormones most probably reflect a prolonged stress response 2-5 months after severe brain injury, rather than pituitary insufficiency per se. These endocrine alterations thus seem to reflect a more severe disease state and relate to 1-year functional outcome.

MeSH terms

  • Adult
  • Brain Injuries / blood*
  • Brain Injuries / complications
  • Female
  • Follow-Up Studies
  • Glasgow Outcome Scale
  • Gonadal Hormones / blood*
  • Humans
  • Hydrocortisone / blood*
  • Insulin-Like Growth Factor I / analysis*
  • Male
  • Middle Aged
  • Pituitary Hormones / blood*
  • Stress, Psychological / blood*
  • Stress, Psychological / etiology
  • Thyroid Hormones / blood*

Substances

  • Gonadal Hormones
  • IGF1 protein, human
  • Pituitary Hormones
  • Thyroid Hormones
  • Insulin-Like Growth Factor I
  • Hydrocortisone