Endocrine Abstracts

Objective: To estimate the occurrence of hypopituitarism 12 months following traumatic brain injury (TBI), describe the time course, evaluate the predictive value of early hormonal changes and trauma related parameters, as well as out-come.

Methods Forty-six patients with TBI (mild (GCS:13–15) n=22; moderate (GCS:9–13) n=9; severe (GCS<9) n=15) were included. Patients were tested early post-injury (baseline hormone levels + Synacthen-test), and re-tested at 3 and 12 months post-injury (baseline + post-stimulatory hormone levels performing an insulin tolerance test or if contraindicated an arginineGHRH-test).

Results: In the early post-traumatic phase, pituitary hormone alterations were observed in 34/46 (74%) of TBI patients, primarily affecting the gonadal (31/46) and thyroidal (15/46) axes. These changes were most prevalent in severe TBI. At three months, 6/46 patients failed anterior pituitary testing. Twelve months post-injury, one patient had recovered, whereas one developed GH-deficiency in addition to existing ACTH-deficiency. No patients being sufficient at 3 months developed insufficiency during the 9 months follow-up. All insufficient patients had GH-deficiency (5/46 (11%)), followed by ACTH- (3/46), TSH- (1/46), LH/FSH- (1/46) and ADH-deficiency (1/46). The risk of long-term hypopituitarism was positively related to trauma severity (P=0.04; 4=severe TBI; 1=moderate TBI), but unrelated to early hormonal alterations when adjusted for trauma severity (P>0.1). Insufficient patients had lower self-evaluated health status (P=0.05), and a higher increase in BMI (P=0.01) and total cholesterol (P=0.04) as opposed to sufficient patients.

Conclusion: Head trauma patients had a high frequency of non-specific early hormonal alterations being non-predictive of long-term posttraumatic hypopituitarism. The prevalence of long-term posttraumatic hypopituitarism is clinically relevant in patients with severe TBI, and these patients should be referred to neuroendocrine evaluation in the stable posttraumatic phase. Clinicians should moreover become aware of potential hypoadrenalism in the initial posttraumatic period, as insufficiencies are most certainly present in some patients already from the eliciting trauma.