Growth hormone deficiency and hypopituitarism in adults after complicated mild traumatic brain injury

Traumatic brain injury is considered the main cause of hypopituitarism in adults, and GH deficiency appears to be the most frequent pituitary deficit. Most of the available studies have included all degrees of severity of trauma. We aimed to assess pituitary function and GH deficiency in adult patients at different time lengths after complicated mild TBI according to Glasgow Coma Scale. We also aimed to evaluate whether mild TBI patients with GH deficiency had developed alterations in the glycolipid profile.

Forty-eight patients (34 men and 14 women) with complicated mild TBI were included in the study. Twenty-three patients were evaluated at 1 year (Group A) and 25 patients at 5 years or longer after the injury (Group B). All patients underwent basal hormonal evaluation for pituitary function. GH deficiency was investigated by the combined test (GH releasing hormone + arginine). The glycolipid profile was also evaluated.

GH deficiency occurred in 8/23 patients (34.7 %) of Group A and in 12/25 patients (48 %) of Group B. In addition, two patients, one in each group, showed evidence of central hypothyroidism. Patients with GH deficiency, especially in Group A, presented a higher frequency of visceral adiposity and adverse metabolic profile as compared to no-GH deficiency patients.

Patients examined at 1 year or several years from complicated mild TBI had a similarly high occurrence of isolated GH deficiency, which was associated with visceral adiposity and metabolic alterations. Our findings suggest that patients undergone complicated mild TBI should be evaluated for GH deficiency even after several years from trauma.