Heading in soccer linked to a decline in brain function

By Imogen Howse via SWNS

Heading a football has been linked to a “measurable” decline in the microstructure and function of the brain over a two-year period.

A new study examined 148 young adult amateur football players by determining how often they hit the ball with their head.

Players then had their memory and verbal learning performance assessed and underwent diffusion tensor imaging (DTI) - an MRI technique which characterizes the microstructure of the brain – both at the start of the study and again two years later.

Those in the "high-heading" group (over 1,500 headers in two years) demonstrated an increase of diffusivity in frontal white matter regions and a decrease of orientation dispersion index (a measure of brain organization).

These results were similar to those seen in people with mild traumatic brain injuries - and were also accompanied by a decline in verbal learning performance.

Lead author Dr. Michael Lipton, of Columbia University, said: “There is enormous worldwide concern for brain injury in general and in the potential for football heading in particular to cause long-term adverse brain effects.

“A large part of this concern relates to the potential for changes in young adulthood to confer risk for neurodegeneration and dementia later in life.”

Previous research has examined the adverse effects football heading has on the brain at a single point in time, but this study looked at the impacts over a two-year period – with the analysis adjusted for variables including age, sex, education, and history of concussion.

Dr. Lipton said: “When we first started, there was no method for assessing the number of head impacts a player experienced.

“So, we developed a structured, epidemiological questionnaire that has been validated in multiple studies.

“Our analysis found that high levels of heading over the two-year period were associated with changes in brain microstructure similar to findings seen in mild traumatic brain injuries.

“High levels of heading were also associated with a decline in verbal learning performance.

“This is the first study to show a change of brain structure over the long-term related to sub-concussive head impacts in football.”

Dr. Lipton and his colleagues also presented another study, in which they used DTI to investigate the association between repetitive head impacts from football heading and verbal learning performance.

Here, researchers analyzed football heading in 353 amateur football players between the ages of 18 and 53 over a 12 month period – and then had them undergo DTI and verbal learning performance testing.

While prior research has focused on deep white matter regions in the brain, this study evaluated the integrity of the interface between the brain’s gray and white matter, which are located closer to the skull.

“Importantly, our new approach addresses a brain region that is susceptible to injury but has been neglected due to limitations of existing methods,” Dr Lipton said.

“Application of this technique has potential to disclose the extent of injury from repetitive heading, but also from concussion and traumatic brain injury to an extent not previously possible.”

Researchers discovered that the normally sharp gray to white matter interface was blunted in proportion to high repetitive head impact exposure.

Dr. Lipton added: “We used DTI to assess the sharpness of the transition from gray matter to white matter.

“In various brain disorders, what is typically a sharp distinction between these two brain tissues becomes a more gradual or fuzzier transition.

“These findings therefore add to the ongoing conversation and contentious debate as to whether football heading is benign or confers significant risk.”

Dementia has killed five members of England's World Cup-winning team of 1966.

They include Ray Wilson, Martin Peters, Jack Charlton, his brother Bobby Charlton and Nobby Stiles.

The latest findings, due to be presented later this week at the annual meeting of the Radiological Society of North America (RSNA), add to growing concern about the health effects of headers first raised following the death, aged just 59, of former England and West Bromwich Albion striker Jeff Astle in 2002.

The cause of his death was a degenerative brain disease that had first become apparent as much as five years earlier.

A coroner found that the repeated minor trauma of heading the ball had been the cause of Astle's death, as the leather footballs used in his playing days were considerably heavier than the plastic ones used later, especially when wet.

In 2015, his family launched the Jeff Astle Foundation, raising awareness of brain injury in all forms of sport, as well as offering support to those affected.

The charity has grown in size with high profile patrons include high profile former England internationals Alan Shearer and Gary Neville.