Pituitary functions in the acute phase of traumatic brain injury: are they related to severity of the injury or mortality?

PRIMARY OBJECTIVE There are only limited data regarding pituitary functions in the acute phase of traumatic brain injury (TBI) and previous studies have been conducted in only small cohorts of subjects. Therefore we have investigated the pituitary functions in the early acute phase, within 24 hours of trauma, in 104 patients with TBI. Additionally, the relationships between basal pituitary hormones, severity of the trauma and mortality due to trauma were also investigated. METHODS AND PROCEDURES One hundred and four TBI patients were included in the study consecutively. All patients underwent basal hormonal evaluation within the first 24 hours of admission. Twenty of 104 patients died during the acute phase. MAIN OUTCOMES Prolactin levels were negatively correlated with the Glasgow coma scale (GCS), cortisol levels were positively correlated with the GCS and cortisol levels were positively correlated with ACTH levels. Additionally there was a significant positive correlation between the total testosterone levels and the GCS in males. Logistic regression analysis revealed that mortality after TBI was unrelated to basal pituitary hormone levels. However age and GCS were significantly related to the mortality. The percentages of pituitary hormone deficiencies were as follows: 3.8% had TSH deficiency, 40.0% had gonadotrophin deficiency, 8.8% had ACTH deficiency and 20.0% had GH deficiency. CONCLUSIONS Present data clearly demonstrate that pituitary function is disturbed in TBI and the most frequently deficient pituitary hormones were gonadotrophins in the early acute phase of TBI. Basal hormone levels including cortisol, prolactin and total testosterone were related to the severity of the trauma. However there was no relation between basal hormones and mortality due to TBI. Age and GCS were significantly related to mortality.