Concussion rates higher than previously reported, Ont. study suggests

Increasing awareness and understanding of concussions are allowing researchers to better track the prevalence of the condition, a new study suggests, noting that rates of such injuries in Ontario are about twice as previously reported.

A team of researchers with Toronto's University Health Network combed through patient data collected throughout the province between 2008 and 2016 and assessed the number of diagnosed and suspected concussions treated during that time.

The resulting study, published in the Journal of Head Trauma Rehabilitation, found that the number of patients experiencing concussions and their side effects were considerably higher than past research had led them to expect.

Study co-author and concussion rehabilitation specialist Dr. Mark Bayley said past efforts to study concussions focused on smaller sample groups, such as participants in a specific sport or patients seeking treatment through one particular avenue such as an emergency department.

The larger research sample in this study, he said, gave him and his peers a better sense of both the scope of the problem and the factors underpinning their findings.

"It does appear that this is due to increasing awareness more than to an increased actual incidents of concussion," Bayley said in an interview Wednesday. "What people used call 'bell-ringer' or 'seeing stars' is now being more frequently recognized as a concussion and something that needs to be monitored for prevention of complications."

Bayley said previous research had pegged the concussion rate in Ontario at roughly 600 per every 100,000 people, a figure he and his colleagues suspected fell short of actual levels.

By mining Ontario patient data compiled by the Institute for Clinical and Evaluative Sciences, Bayley and other researchers concluded the real figure was almost twice as high.

The study found more than 1.3 million concussion patients between 2008 and 2016. The annual average concussion rate in the province during that stretch was 1,153 per 100,000 people or about 1.2 per cent of the province's population, the data suggested.

Bayley said that while the rates were fairly consistent, researchers tracked some upticks in the number of diagnoses that coincided with high-profile instances of concussions in the pop-culture spotlight. Those ranged from hockey star Sidney Crosby's previous concussion diagnoses to the 2015 movie Concussion, chronicling a researcher's efforts to sound the alarm about the impact the condition can have on professional football players.

Of all the concussions identified in the study, Bayley said 79 per cent of them were diagnosed in a hospital emergency department, though he noted that the number flagged by primary care doctors had spiked noticeably in 2016.

Urban and rural divide

The study also identified differences in concussion rates along age, gender and geographic lines.

It found children under five were the most likely demographic to experience a concussion, followed by women over the age of 65.

Men, however, were more likely to contend with the condition than women across the population as a whole.

Bayley said one of the most striking findings related to the divide between urban and rural residents.

He said those living in more remote communities were significantly more likely to experience a concussion than those based in cities, noting rural rates could be as high as 1,400 per 100,000 people.

He said researchers did not examine the causes of the concussions in the study, though he flagged increased reliance on car travel and higher number of jobs involving heavy equipment as possible factors behind the rural rates.

What is known, he said, is that the bulk of Ontario's concussion treatment and rehabilitation resources are concentrated in urban centres where the need is not as great.

"We need to make sure that those individuals have access to care," he said of rural residents. "And we need to be innovative in this way."

Bayley said increasing telephone or video access to health resources may go some way to closing the gap with city-dwellers, noting that much of the key to successful concussion recovery involves gaining access to quality treatment protocols and reliable information about symptom management.

But he said he hopes the latest research will also encourage an increase in the number of concussion clinics and experts in more remote areas.

"There's a large number of people suffering from the complications of concussion," he said. "We believe that better care earlier on would result in more people getting better sooner."

The study was based on administrative health databases that depend on physicians to accurately diagnose and report concussions.