Research Reports - Hypothalamic-pituitary dysfunction following traumatic brain injury affects functional improvement during acute inpatient rehabilitation
J Head Trauma Rehabil. 2013 Sep-Oct;28(5):390-6
Rosario ER, Aqeel R, Brown MA, Sanchez G, Moore C, Patterson D
OBJECTIVE: To evaluate the occurrence of hypothalamic-pituitary dysfunction
following a traumatic brain injury (TBI) and to determine its effect on
functional improvement in acute inpatient rehabilitation.
METHODS: A retrospective chart review identified male patients with a primary
diagnosis of TBI with or without a skull fracture, an onset date within 6 months
prior to admission, and were 16 years of age or older. The percentage of
individuals in this population with abnormal hormone levels was determined on the
basis of the established normal reference range for each hormone assay. The
functional independence measure, which assesses functional outcomes in acute
inpatient rehabilitation, was used to examine the relationship between hormone
levels and functional improvement.
RESULTS: Hypothalamic-pituitary dysfunction was identified in nearly 70% of men
following TBI. Hypogonadism, or low testosterone levels, was observed in 66% of
the patients, followed by low levels of free T4 in 46% and low levels of insulin
growth factor-1 in 26% of patients. Hypopituitarism associated with impaired
functional recovery. Specifically, the functional independence measure change per
day was significantly lower in patients with low levels of testosterone and
insulin growth factor-1.
CONCLUSIONS: These findings suggest the importance of testosterone and insulin
growth factor-1 activity in the early stages of physical and cognitive