How Common are Thyroid Disorders after Childhood TBI?

Neuroendocrine dysfunction is a common consequence that can progress from several months to years after a traumatic brain injury (TBI). A TBI sustained in childhood is often associated with disorders such as hypopituitarism and abnormalities in thyroid function later in life. As a result of the time lapse between the injury and a neuroendocrine diagnosis, it can be difficult to connect a cause and effect between the two. Past research has shown conflicting results, and it has been difficult to demonstrate a reliable rate of risk.

A recent study suggests that the incidence of permanent hypopituitarism following childhood TBI may be overestimated. However, research did show that some disturbance in pituitary function occurs following TBI, as the concentration of peripheral thyroid hormones were lower in children with TBI than they were in children who did not have a TBI. Furthermore, increased severity of TBI was shown to be associated with lower concentration of thyroid-stimulating hormones.

In the long term, individuals who experienced TBI in early childhood may have lower levels of thyroid-stimulating hormone, but they typically remain within the lower end of a normal range. Changes in thyroid function post-injury may be less obvious than previous studies have suggested, but still may reflect minor hypothalamic-pituitary damage that is important to assess.

Source: Heather NL, Derraik JGB, Chiavaroli V, et al. Increasing severity of traumatic brain injury in early childhood is associated with a progressive reduction in long-term serum thyroid-stimulating hormone concentrations. Clinical Endocrinology. (March 2016.)