The hypothalamic-pituitary axis (HPA) sits deep near the center of the brain, and is responsible for the production and distribution of hormones. The HPA is vulnerable to injury, and several studies have found that people who have sustained a traumatic brain injury will also show damage in the HPA. Decreased levels of certain hormones such as testosterone, growth hormone, and IGF-1 have also been documented in people who have sustained a traumatic brain injury, with levels continuing to decrease in the months and years after the injury.
A recent study sought to determine if low hormone levels have an effect on recovery during rehabilitation. The researchers found that nearly 70% of the traumatic brain injury patients in an acute rehabilitation facility showed hormone dysfunction. When they measured functional improvement on a daily basis, those patients who had low hormone levels performed significantly worse than those who did not.
The researchers suggested that traumatic brain injury patients should be routinely monitored for hormone levels soon after the injury, and that the administration of supplemental hormones may improve performance during rehabilitation.
Rosario ER, Aqeel R, Brown MA, et al. Hypothalamic-pituitary dysfunction following traumatic brain injury affects functional improvement during acute inpatient rehabilitation. Journal of Head Trauma Rehabilitation. (October 2013).