gms | German Medical Science

Objective: While neuroendocrine dysfunction at some time point following traumatic brain injury (TBI) has been described in a large number of studies in recent years, there is a lack of longitudinal studies comparing initial laboratory findings of pituitary hormones in the acute period with the results of functional testing of the hypothalamic-pituitary insufficiency more than a year post-injury. The present study was designed to fill this gap.

Methods: In 82 consecutive patients admitted for TBI, the cortico-, thyreo-, gonado- and somatotropic as well as the posterior pituitary function were examined on day 0, 3 and 7 post-injury. To date, in 14 patients dynamic endocrine testing 30-36 months after the trauma is available. Recovery was assessed by the Glasgow Outcome Scale (GOS) at 6 months and by the Nottingham Health Profile at 30-36 months. Consent from the ethical committee was obtained.

Results: Age ranged from 18-92 years (mean 52) and trauma severity was mild to severe (initial Glasgow Coma Score, GCS, 3 to 15). In the acute post-trauma period, most of the patients suffered from hypothalamo-pituitary dysfunction (25% cortico-, 46% thyreo-, 83% gonado- and/or 23% somatotropic system), while at the last follow-up one third of patients demonstrated clinical findings suggestive of hypopituitarism. Dynamic testing of the corticotropic system by an ACTH-test revealed an insufficient increase in all patients (compared to age-matched controls). Growth hormone (GH) deficiency as examined by the GHRH-Arginine test was found in 50%. One patient had an absolute loss of growth hormone secretion (increment <3ng/ml). However, no significant association of GCS or GOS and pituitary dysfunction was established.

Conclusions: The prevalence of hypopituitarism may be as high as 80% early after TBI with some 50% persistent endocrine insufficiency for years, altogether suggesting an alarming socio-economic impact. Since none of our patients had been offered hormonal replacement therapy, we conclude that a substantial percentage of these patients remain undiagnosed and untreated.