A new study highlights the high death toll of brain injuries that often goes unnoticed. According to the findings published in CMAJ, adults with a history of one concussion are three times more likely to commit suicide compared to those without a history of concussion. Curiously, that risk was amplified further in those who experienced a brain injury on a weekend.
Past research has found links between the development of depression and suicidal thoughts in those with TBI, and increased risk of suicide in veterans and football players. However, the researchers wanted to see if those findings translated to the general population.
“For years there have been examples of serious head injuries leading to potential cases of suicide in military veterans and professional athletes,” senior author Dr. Donald A. Redelmeier told Reuters. “I always worried that even mild concussions acquired in normal community settings might also be a risk, and might cause lasting damage.”
For the study, the researchers reviewed diagnostic codes from a health insurance database including information from over 235,000 individuals who had experienced a concussion over a 20-year period in Ontario, Canada.
The majority of the participants had not previously attempted suicide, been hospitalized, or had a psychiatric disorder. The researchers also distinguished from recreational and occupational head injuries by comparing head injuries that occurred on weekdays to those that occurred on weekends.
Throughout the approximately nine-year follow-up period, 667 people included in the study died from suicide. Of those, 519 experienced a concussion on a weekday, while the other 148 experienced their head injury on a weekend.
The mean time between concussion and the subsequent suicide was almost six years.
While more people who experienced head injuries on a weekday committed suicide overall, the absolute calculated risk was highest among those who experienced their brain injury on a weekend.
When calculated, the suicide rate for those who experienced a concussion was three times higher than that of the population, while the rate was four times higher for those who had a concussion on the weekend.
Redelmeier suggested this discrepancy in suicide rate may because concussions experienced during recreational activity are frequently ignored or not properly checked out.
The team also noted the suicide risk among those with concussions was consistent across demographics and record of past psychiatric conditions. “It became accentuated with time and exceeded the risk among military personnel. Half of these patients had visited a physician in the last week of life,” the researchers wrote.
The findings highlight the need for increased screening of depression and suicidal ideation among those who have experienced brain injuries, so that professionals can intervene early.