Endocrine Changes After Brain Injury 

While awareness is increasing regarding the health effects of concussion and other traumatic brain injury (TBI), the potential effects from neuroendocrine changes remain underappreciated. Deficiencies in hormones made by the pituitary gland are seen at a higher rate in patients who have sustained TBI, with reports of chronic pituitary dysfunction in 15-60% of adults[1] and up to 42% of children and adolescents[2] after TBI. These deficiencies may resolve over time, or develop years after injury.

It is particularly important to consider pituitary dysfunction in patients with persistent symptoms after TBI, as these deficiencies can be addressed.  Deficiencies in pituitary hormones – “hypopituitarism”—impact health and quality of life and, if left untreated, are associated with increased morbidity.[3]  Symptoms may be include fatigue and ‘mental fog,’ irregular menses, decrease in libido or spontaneous morning erections, and new changes to weight/skin/hair.  Careful evaluation can diagnose any pituitary deficiencies, and deficient hormones can be replaced.

The pituitary is responsible for ensuring that several hormonal axes stay balanced: stress hormone (cortisol), thyroid hormone, reproductive hormones, and growth hormone. Any of these may be affected. Growth hormone deficiency is now the most commonly reported chronic post-TBI deficiency, and replacement of growth hormone has been associated with improved quality of life and physical parameters.  It is important to carefully evaluate pituitary hormones in order to determine whether there is a deficiency; post-concussion symptoms which are due to pituitary dysfunction should be alleviated by replacement.

[1] Aimaretti et al 2005; Bondanelli et al. 2004; Emelifeonwu et al 2020; Kreber et al. 2016; Schneider et al. 2006

[2] Krahulik et al. 2017; Niederland et al 2007, Reifschneider et al. 2015; Ulutabanca et al. 2014

[3] Jasim et al 2017; Olsson 2016; Pappachan et al 2015; Rosen 1990; Tomlinson et al 2001; Wexler et al 2009