BOSTON—Blast-related concussions, which are often linked to hormonal changes leading to problems such as sleep disturbances, fatigue, depression, and poor quality of life, may be prevalent in US military veterans, according to results from a new study conducted in male US service members who had been deployed to Iraq or Afghanistan.
In civilians, chronic hypopituitarism, defined as a deficiency in the production of 1 or more pituitary hormones for at least 1 year after injury, affects a significant portion of people who have experienced concussions, also referred to as mild traumatic brain injury (TBI), researchers who presented the findings at ENDO 2016 reported.
“Although studies in civilians indicate a 25% to 50% prevalence of hormonal deficiencies resulting from brain injuries, surprisingly there are limited data on their prevalence and symptoms in military veterans,” said Charles Wilkinson, PhD, of the Veterans Affairs (VA) Puget Sound Health Care System in Seattle.
Given that blast-related concussions account for 80% of the TBI diagnoses among US military services members, Dr Wilkinson and colleagues sought to learn more about potential pituitary dysfunction in this patient population.
“Some of these hormone deficiencies, which mimic some symptoms of posttraumatic stress disorder (PTSD) may be treated successfully with hormone replacement if correctly diagnosed,” said Dr Wilkinson.
The researchers evaluated blood samples from 27 male veterans with 1 or more blast concussions sustained at least 1 year earlier and from 14 previously deployed male veterans with no history of blast exposure. Basal morning levels of insulin-like growth factor I (IGF-1), luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin, free and total testosterone, thyroid-stimulating hormone (TSH), thyroxine, adrenocorticotropic hormone (ACTH), and cortisol were measured. The researchers assessed growth hormone deficiency and secondary adrenal insufficiency through provocative testing with the glucagon stimulation test (GST). Body composition was also measured.
Results revealed that 12 of 27 veterans who had experienced blast concussions (44%) had chronic hypopituitarism vs only 1 in the 14 study participants without blast injuries (7%).
Growth hormone deficiency, which can negatively affect cognition, mood, sleep, and metabolism, was the most common hormone deficiency, the researchers noted. Adrenal insufficiency, hypogonadism, and thyroid hormone deficiency either alone or in combination were also evident in those with hypopituitarism.
The researchers also collected data via behavioral questionnaires on the number of blast exposures, length of deployments, sleep quality, fatigue, cognitive function, depression, and symptoms of PTSD.
Surprisingly, on every test, participants with mild TBI and hypopituitarism experienced more problems compared with those with mild TBI but no hypopituitarism, noted Dr Wilkinson. These participants had significantly poorer overall sleep quality, more depressive symptoms, and were more easily fatigued than those with mild TBI and normal hormone levels.
“The value of screening for hormonal abnormalities after concussions, particularly in the presence of chronic symptoms, is currently a matter of debate,” Dr Wilkinson said. “Yet, if the possibility of hormone deficiencies in our veterans is not considered, appropriate treatment may not occur.”
This study was funded by the Department of Veterans Affairs. The researchers report no relevant financial disclosures.
- Colasurdo EA, Pagulayan KF, Burges DE, et al. SAT-480. Chronic hypopituitarism is prevalent after blast concussion in deployed military personnel. Presented at: ENDO 2016; April 1-4, 2016; Boston, MA.