Variations of pituitary function over time after brain injuries: the lesson from a prospective study

Traumatic Brain Injury (TBI) and Subarachnoid Haemorrhage (SAH) are conditions at high risk to develop hypopituitarism as pointed out by many papers in scientific literature. But most of the papers were referred to retrospective evaluations, not considering the possible evolution of the pituitary function over time. Aim of our studies was to clarify whether pituitary deficiencies and normal pituitary function recorded at short term follow-up (3 months), would improve or worsen, respectively, at long term (12 months after the brain injury). In a multicenter study protocol, in patients who suffered TBI (n = 70; 50 Males, 20 Females; age 39.31 +/- 2.4 years; BMI 23.8 +/- 0.4 kg/m(2)) or SAH (n = 32; 12M, 20F; age: 51.9 +/- 2.2 year; BMI: 24.7 +/- 0.6 kg/m(2)) we tested 3 and 12 months after the pathological events the pituitary function. In TBI patients, the 3 month evaluation had shown some degree of hypopituitarism in 32.8% and the 12 months retesting demonstrated some degree of hypopituitarism in 22.7%. Total hypopituitarism was always confirmed at 12 months while Multiple and Isolated deficits recorded at 3 months was confirmed in nearly 25% only of the patients. On the other hand, in 5.5% of TBI with normal pituitary function at 3 months Isolated deficits were recorded at 12 months testing. Moreover, in 13.3% of TBI with Isolated deficit at 3 months Multiple hypopituitarism was demonstrated at 12 months retesting. In SAH patients, the 3 months evaluation had shown some degree of hypopituitarism in 46.8% and the 12 month retesting demonstrated some degree of hypopituitarism in 37.5%. No multiple hypopituitarism recorded at 3 months was confirmed at 12 months, but 2 patients with isolated deficits at 3 months showed multiple hypopituitarism at 12 month retesting. At 12 as well as at 3 months, both in TBI and SAH patients, the most common deficit was severe GHD (>20%) followed by secondary hypogonadism and then hypoadrenalism and hypothyroidism. In all, in patients who experienced TBI or SAH the risk to develop hypopituitarism is very high; early diagnosis of total hypopituitarism is always confirmed at the long term follow-up; however pituitary function in brain injured patients may improve over time, because, isolated and even multiple pituitary insufficiencies recorded at short term can be transient; on the other hand normal pituitary function recorder at short term may, become impaired 12 months after the injury. Thus, brain injured patients must undergo neuroendocrine follow-up over time in order to monitoring pituitary function and eventually providing appropriate placement.