Prevalence and predictive factors of post-traumatic hypopituitarism.
OBJECTIVE
To estimate the prevalence and predictive factors of hypopituitarism following traumatic brain injury (TBI).


METHODS
A cross-sectional cohort study.


METHODS
One hundred and four hospitalized TBI patients (26F/78M), median age 41 (range 18-64) years, body mass index (BMI) 25 (17-39) kg/m(2); severity: mild [Glasgow Coma Scale (GCS) score 13-15) n = 44, moderate (GCS 9-12) n = 20, severe (GCS < 9) n = 40].


METHODS
Patients were evaluated 13 (10-27) months post-injury, with measurement of baseline (0800-1000 h) and post-stimulatory hormonal levels during an insulin tolerance test (ITT) (86%) or, if contraindicated, an arginine(arg)-GHRH test + Synacthen test (14%). Insufficiencies were confirmed by retesting.


RESULTS
Hypopituitarism was found in 16 (15%) patients, affecting one axis in 10, two axes in four and more than two axes in two patients. The GH axis was most frequently affected (15%), followed by secondary hypoadrenalism (5%), hypogonadism (2%), hypothyroidism (2%) and diabetes insipidus (2%). The risk of pituitary insufficiency was increased in patients with severe TBI as opposed to mild TBI [odds ratio (OR) 10.1, 95% confidence interval (CI) 2.1-48.4, P = 0.004], and in those patients with increased intracerebral pressure [OR 6.5, 95% CI 1.0-42.2, P = 0.03]. Patients with only one affected axis were all GH deficient; 60% (n = 6) of these were overweight or obese.


CONCLUSIONS
The prevalence of hypopituitarism was estimated at 16%. Although high, this value was lower than previously reported, and may still be overestimated because of well-known confounding factors, such as obesity. Indicators of increased TBI severity were predictive of hypopituitarism, with a high negative predictive value. Neuroendocrine evaluation should therefore be considered in patients with severe TBI, and in particular in those with increased intracerebral pressure (ICP).
Klose
M
M
Department of Medical Endocrinology, the University Hospital of Copenhagen, Blegdamsvej 9, DK-2100 Copenhagen, Denmark. klose@rh.dk
Juul
A
A
Poulsgaard
L
L
Kosteljanetz
M
M
Brennum
J
J
Feldt-Rasmussen
U
U
D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000172:deficiency; D000328:Adult; D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D001930:Brain Injuries / Q000150:complications* / Q000503:physiopathology; D004812:Epidemiologic Methods; D005260:Female; D013006:Growth Hormone / Q000172:deficiency; D006801:Humans; D007018:Hypopituitarism / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D007986:Luteinizing Hormone / Q000172:deficiency; D008297:Male; D008875:Middle Aged; D010901:Pituitary Function Tests; D010903:Pituitary Gland, Anterior / Q000503:physiopathology; D012737:Sex Factors; D013972:Thyrotropin / Q000172:deficiency
D000324:Adrenocorticotropic Hormone; D007986:Luteinizing Hormone; D013972:Thyrotropin; D013006:Growth Hormone