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 +/- 14 yrs; 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 < 200 nmol/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.