Hypopituitarism following traumatic brain injury (TBI): call for attention.

Recent studies have demonstrated that hypopituitarism, in particular GH deficiency, is common among survivors of traumatic brain injury (TBI) years tested several months or following head trauma. In addition, it has been shown that post-traumatic neuroendocrine abnormalities occur early and with high frequency. These findings may have significant implications for the recovery and rehabilitation of patients with TBI. Although data emerging after year 2000 demonstrate the relevance of the problem, in general there is a lack of awareness in the medical community about the incidence and clinical repercussions of the pathology. Most, but not all, head trauma associated with hypopituitarism is the result of motor vechicle accidents. The subjects at risk are those who have suffered moderate-to-severe head trauma, although mild intensity trauma may also precede hypopituitarism. Particular attention should be paid to this problem in children and adolescents; onset of pituitary deficits can evolve over years following injury. Plasma IGF-I concentrations, plus dynamic GH testing, are indicated for the assessment of the GH-IGF axis in TBI patients. Some degree of hypopituitarism is found in 35-40% of TBI patients. Among mulitple pituitary deficits, the most common ones were GH deficiency (GHD) and gonadotrophin deficiency. In most series, 12-15% presented with severe GHD and 14% with partial GHD after stimulating GH secretion, confirming that the most common isolated deficit is GHD. Psychometric evaluation and neurocognitive testing show variability of disability, and these measures are needed and important to support hormonal replacement. Preliminary data, from small pilot, open-label studies show that subjects treated with GH experience significant improvements in concentration, memory, depression, anxiety and fatigue. In conclusion, pituitary failure can occur even in minor head injuries and is poorly recognized.