Adults who have concussion are three times more likely to commit suicide than the average population. A new study published online in the Canadian Medical Association Journal on Feb. 8 suggests that physicians must take suicide risk into account when treating patients with concussion.

The researchers note that concussion is the most common brain injury in adults. Co-author Michael Fralick, a medical trainee at the University of Toronto, points out that the injury is not limited to athletes or soldiers.

The study involved analysing 235,110 concussion cases in the past 20 years in Ontario, Canada. The patients were 41 years old on the average and half were men, without previous suicide attempt, mental disorder or hospitalisation. To distinguish between recreational and occupational injuries, the concussions that occurred on a weekend were compared to the ones that occurred on a weekday.

ConcussionDoric Donell | Australia Network News

About 667 suicides were recorded after a follow-up, 9.3 years later. Interestingly, if the concussion occurred over the weekend (recreational), the risk was four times higher, about 39 suicides per 100,000 annually, while people who had concussion on weekdays (occupational) were three times more likely to take their own lives, about 29 suicides per 100,000 annually.

The researchers note that it would take about 5.7 years from the concussion incident before a person commits suicide. Any additional concussion after the initial incident added the risk. Apparently, the most common method of suicide was overdosing from drugs. On the average, they were 44 years old and majority visited their family physicians a month before suicide.

Previous studies have associated concussion with suicide risk but this is the first one to observe the difference between concussions experienced on the weekends and weekdays. The study intends to inform physicians and patients about concussion risks and suicide prevention.

“Given the quick usual resolution of symptoms, physicians may underestimate the adverse effects of concussion and its relevance in a patient’s history,” says Donald Redelmeier, a senior core scientist at the Institute for Clinical Evaluative Sciences (ICES) and a physician at Sunnybrook Health Sciences Centre in Toronto. “Greater attention to the long-term implications of a concussion might save lives because deaths from suicide can be prevented.”