The risk of suicide is up to four times higher in adults who have had concussion
The risk of suicide is up to four times higher in adults who have had concussion compared with those who haven’t, a large Canadian study suggests.
Following 235,000 patients with concussion for 20 years, the researchers found that weekday concussions were associated with a three-fold increased risk of suicide, and weekend concussions with a four-fold increase.
“Given the quick usual resolution of symptoms, physicians may underestimate the adverse effects of concussion and its relevance in a patient’s history,” study author Dr Donald Redelmeier, senior core scientist at the Institute for Clinical Evaluative Sciences, Toronto, Ontario, said.
“Greater attention to the long-term implications of a concussion might save lives because deaths from suicide can be prevented,” Dr Redelmeier said.
This is the first study to look at the link between suicide and concussion based on whether it was a weekday or a weekend. A weekend concussion would suggest the accident was recreational rather than occupational.
Patients with concussion completed suicide at a rate of 29 per 100,000 people annually, which was three times higher than the average. Those with a weekend concussion had an absolute risk of suicide four times higher than the population norm, at 39 per 100,000 people annually.
“The link between concussion and suicide is not confined to professional athletes or military veterans,” Mr Michael Fralick, coauthor and medical trainee at University of Toronto, said.
Concussion is the most common type of head injury in Australia, according to the Victorian Better Health Channel.
Most of the concussion patients had no previous attempts at suicide, hospitalisation or a past psychiatric disorder. The mean age was 41 years, and the majority lived in the city.
The researchers found that there was a dose-response relationship and that the risk of suicide was accentuated over time. Previous suicide attempts were still a stronger predictor of completed suicide than concussion though.
“The increased long-term risk of suicide observed in this study persisted among those who had no psychiatric risk factors and was distinctly larger than among patients after an ankle sprain,” wrote the authors.
Half of the patients visited a doctor in the last week of life, typically for a diagnosis that was not mental-health related.
CMAJ 2016; online Feb 8