Pituitary hormone problems common in soldiers with moderate to severe blast-related brain injuries

The study looked at 19 UK soldiers with moderate to severe brain injury caused by blasts from Improvised Explosive Devices (IEDs) while on duty in Afghanistan, and a group of 39 individuals with moderate to severe traumatic brain injuries caused by road traffic accidents, falls and assaults, rather than explosive blasts. They found that a much higher proportion of soldiers with blast injuries were likely to have pituitary hormone problems (32 per cent) than in the non-blast control group (2.6 per cent). One in five of the soldiers ended up receiving hormone treatment with growth hormone, testosterone and/or hydrocortisone (replacing the stress hormone cortisol).

The study also showed that the soldiers who had pituitary dysfunction following blast injury had more severe damage to white matter connections within the brain, and more severe cognitive problems, such as being slow in processing information, than those who did not have hormone problems.

The recent conflicts in Iraq and Afghanistan have seen rapid advances in personal protective equipment and in the medical management of severe trauma. These gains have meant that increasing numbers of soldiers are surviving previously fatal and complex injuries.

Injuries caused by IEDs are so numerous that they have been called the ‘signature injury’ of these conflicts. Just between December 2009 and March 2012, 183 UK soldiers survived a moderate-severe blast traumatic brain injury TBI in Afghanistan. The total number of such injuries amongst US troops is much higher. The complex physical forces involved in a blast have led to much speculation about how the blast wave itself causes brain injury.

The patients were treated in the multi-disciplinary traumatic brain injury clinic at the Imperial Centre for Endocrinology at Imperial College Healthcare NHS Trust by Dr Tony Goldstone, Consultant Endocrinologist, and they were scanned at the Computational, Cognitive and Clinical Neuroimaging Laboratory at Imperial College London, by Prof David Sharp, Consultant Neurologist and Major David Baxter, Military Neurosurgeon.

Dr Tony Goldstone from the MRC Clinical Sciences Centre says:

This study was set up to see if there were facets unique to the kind of trauma caused to the brain by IEDs. We found that there was a high prevalence of hormonal problems in soldiers with these kinds of injuries. This study involved a relatively small number of soldiers, and so assessment of additional patients will be needed to confirm such a prevalence rate. However the results do emphasise the importance of actively screening for pituitary problems in all soldiers and others who have had moderate to severe brain injury from exposure to blast. This will enable identification of those who may benefit from hormonal treatments to aid their rehabilitation, recovery and quality of life.”

Air Marshal Paul Evans, Surgeon General said:

“I fully support the research that has been undertaken by Imperial College London and the Ministry of Defence. As Surgeon General, I am committed to ensuring Service personnel benefit from the latest advances in medical research and we continue to conduct research into traumatic brain injury with colleagues at Imperial College London as well as our US and other NATO partners. A Defence Medical Services working group identifies priority areas for TBI research and MOD policy continues to be reviewed in light of emerging best practice. Working in partnership will ensure our personnel benefit as well as enable best practice to be shared between the MOD and NHS.”

Professor David Lomas, Chair of the MRC’s Population and Systems Medicine Board, which funded the research, said:

“Trauma is a serious health problem that has a major impact on people in both a civilian and military setting. By linking academic and military research programmes through studies such as this we will build a greater understanding of acute trauma that will inform future approaches to trauma management, to ensure that people suffering major injury receive the most advanced specialist care.”

The Annals of Neurology study is entitled ‘Pituitary Dysfunction after Blast Traumatic Brain Injury: the UK BIOSAP Study

The UK Blast Injury Outcome Study in Armed forces Personnel (BIOSAP Study) is a collaboration between Imperial College London, the Academic Department of Military Surgery and Trauma and the Defence Medical Rehabilitation Centre at Headley Court.

*The pituitary gland is a small organ at the base of the brain. It secretes several hormones that regulate the secretion of many other hormones produced in different parts of the body. In adults, a lack of growth hormone can produce symptoms including tiredness, low mood, poor emotional and social well-being, as well as increasing body fat, reducing muscle and thinning bones. These problems can be reversed with growth hormone replacement (though adults will not grow any taller). Lack of testosterone can cause tiredness, sexual problems, increased body fat, reduced muscle and thinning of bones. Lack of cortisol can produce tiredness and worse outcomes during illnesses such as infections.

Medical Research Council