Endocrine Abstracts

Aim of the work: Clinical research studies over the last 15 years have reported a significant burden of hypopituitarism in survivors of traumatic brain injury (TBI). However, these endocrine anomalies remain under diagnosed due to nonspecific clinical signs and misunderstanding of the phenomenon. The aim of the work is to evaluate for the first time in Belgium their prevalence and to quantify the deficits of the different pituitary axes in patients recruited to the endocrinology consultation of a university center.

Main results: We studied the data of 74 patients. The prevalence of neuroendocrine disorders in this series is 37.84% (28/74). The biological explorations found: somatotropic deficits (19/28), gonadotropic deficits (9/28), corticotropic deficits (8/28), thyrotrophic deficits (3/28), prolactin deficiency (3/28), prolactin excess (1/28), and diabetes insipidus (1/28). Deficiencies are most often isolated (19/28) rather than associated (9/28). Isolated somatotropic deficiency is the most common (12/28, 42.86%). TBI patients with endocrine deficiencies had significantly higher BMI (30.14±4.62 versus 24.62±4.62 kg/m², P<0.001) than TBI patients without hormonal deficiencies. This can be partly explainable by body composition changes induced by GH deficiency. Indeed, the median BMI of our patients with somatotropic deficiency is significantly higher than in the other patients, while there is no significant difference in BMI for the other deficits. It should be noted that there are not enough cases of disorders of the lactotropic axis and diabetes insipidus to assert a statistically significant difference.

Conclusion: TBI and their consequences are a major public health problem, and hypopituitarism occurs in about 1/3 of cases. No formal risk factors have been identified but it seems that the severity of the trauma is often related to the occurrence of post-traumatic hypopituitarism, although they are encountered in a significant number of mild head injuries. The primary lesions are mechanical and the secondary lesions are vascular. Brain imaging can show lesions or be normal. Most often, only one pituitary axis is affected, and most frequently the somatotropic axis. Deficits can resolve or have a delayed onset. The signs and symptoms of post-traumatic hypopituitarism are most often nonspecific, so that they are not frequently detected. Their prevalence would be underestimated, and their routine screening could ensure that non-tumor causes of hypopituitarism exceed tumor causes.