Prevalence of anterior pituitary dysfunction in patients following traumatic brain injury in a german multi-centre screening program

Introduction: We determined the prevalence of anterior pituitary dysfunction in a multi-centre screening program across five German endocrine centres in patients rehabilitating from TBI (GCS<13). Patients & Methods: 246 patients (39±14yrs; 133 males, 12±8 months after TBI) underwent a series of baseline endocrine tests with central assessment of TSH, free T4, prolactin, LH, FSH, testosterone (m), estradiol (f), cortisol, GH, and IGF-I. If IGF-I was < -2 SDS dynamic testing was performed. GHD was defined according to BMI-dependent cut-off values for GH response to GHRH+arginine of < 4.2, < 8.0 and < 11.5 ng/ml in obese, overweight and lean subjects, respectively, or < 3 micro g/l in ITT. Hypocortisolism was suggested when basal cortisol was <200nmol/l and confirmed by ITT (peak< 500 nmol/l). Results: In TBI patients some degree of impaired pituitary function was shown in 21 % (n=52/246). Total, multiple and isolated deficits were present in 1%, 2 % and 18 %, respectively. 19% had an IGF-I of < - 1 SDS, 9% of < - 2 SDS. In 5% % GHD was confirmed. 9% had hypogonadism. 4% had hypocortisolism and 1 % of patients had confirmed ACTH-deficiency. 12% had TSH-deficiency. Summary: In summary, in this large series carried out on an unselected group of TBI survivors we have found hypopituitarism in every fifth patient with predominantly secondary hypogonadism and hypothyreosis. Regarding somatotrope insufficiency IGF-I is decreased in 50% of GHD patients. Conclusion: These findings strongly suggest that patients who suffer head trauma should routinely undergo endocrine evaluation.