Concussion and Brain Health

Can our days of playing contact sports lead to dementia? Professor James Goodwin explains.

Some seasons ago, Harlequins prop forward and England international rugby player, Joe Marler, woke up in the dressing room, lying on his back, to hear ‘kit man’ Mark Woodward ask him, ‘has your wife brought along the children’? Marler didn’t know what he was talking about. He was asked again, ‘has she brought the kids’? “I just paused and broke down’, said Marler in an interview. ‘I had no recollection of having kids and it just really scared the life out of me”. Marler had been knocked out on the field of play and carried off with concussion.

Sadly, such cases are not rare in contact sports such as American football, rugby, hockey, soccer and unsurprisingly, the military and combat sports such as MMA and boxing. About 3.8 million concussions occur in the US each year in sports. But it’s not just sport. Road traffic accidents, falls and physical assaults all contribute. In the UK, nearly 700,000 people report to the ER each year with head trauma.

It’s true to say that almost none of us go through life without being hit on the head or even being concussed. What are the consequences? Without minimising the aftermath, it’s also true to say that nature has gone a long way to protecting the brain from blows to the head. Our scalp, the bony cranium, the three meninges surrounding the brain and their fluid interior all play their part in cushioning blows to the head. And, let’s not forget the awesome redundancy and resilience of the brain itself. Part of this resilience is synaptic plasticity – the ability of the synapses (connections between brain cells) to resist degradation and preserve cognitive functions despite potentially damaging conditions.

But every system has its limit. Sufficient smaller blows over time or single heavier, more traumatic blows are going to damage the brain’s structure and function. There may be short-term damage and recovery or more substantial long term consequences. Traumatic Brain Injury (TBI) happens when the brain is subject to a sudden, large, external, physical force. Depending on the person’s responsiveness, the injury is classified as mild, moderate or severe.

The consequences of such blows to the head can be serious. So much so that many sports bodies, such as UEFA, the NFL and Rugby Union have or are putting into place safeguarding protocols and detailed guidance on how to prevent or mitigate concussion injuries. Players like David May, former Manchester United defender has revealed that there is an atmosphere of fear now in many retired players – with a possible severe diagnosis on the horizon. And they are right to be worried. Research has found that lifetime soccer players are five times more likely to be diagnosed with neurodegenerative disease than someone who was not a professional player – largely due to heading and head impacts. 

Blows to the head which do not cause outward symptoms of concussion are now called ‘subconcussions’ – and they can be just as deadly. Alix Popham, triathlon athlete and head injury campaigner, has revealed in an interview with The Telegraph his belief that he has potentially suffered thousands of subconcussions throughout his career. “It (competing) was like the Wild West, just mayhem”, he said. “I can’t remember it, mind, but no regrets”.

Subconcussions are so serious because they can’t be detected – until now. As I can reveal for the first time here on our pages, a US company is developing a blood test for subconcussion. It is based on the shower of tiny particles called exosomes (typically 30-150 millionths of a millimeter) that is released from brain fibres when they are injured. The exosomes enter the blood and stimulate the appearance of biomarkers which can be detected by a technique called ‘immuno-assay’. This is a spectacular development. Players will now not have to ‘sit it out’ as the return-to-play decision is made. This test will revolutionise our ability to detect and track subconcussive and concussive brain injuries.

Now the million-pound question. If I am an athlete, boxer or MMA fighter – or even if not – will blows to the head over a lifetime contribute to my risk of dementia? The answer to that is probably, ‘yes’ but we have to qualify it. There are many, many risk factors across our lifetime all of which interact and it’s very difficult to pin down individual values. No one has done that yet.  But we do know that some factors are very powerful and that is why on our pages, we emphasise the ‘brain health pillars’. So in answer to the inevitable question, what do I do about defending my brain, the answer is firstly, try to reduce the incidence of blows to the head if possible; if this is not possible, adopt any measures that your professional sports body recommends, such as head gear or actions to be taken after a concussion. And finally, do everything else you can to power up your brain health: follow the dietary rules, keep physically fit; look after your gut health; get proper sleep; keep an active mind and adopt a healthy lifestyle. It’s never too late to make positive changes to our brain health and that, mercifully, applies to the effects of concussion.