Unlike some previous research, the new work focused on adults in the
general population rather than either athletes or military personnel
with head injuries.
“For years there have been examples of serious head injuries leading
to potential cases of suicide in military veterans and professional
athletes,” said senior author Dr. Donald A. Redelmeier of the
University of Toronto in Ontario.
“I always worried that even mild concussions acquired in normal
community settings might also be a risk, and might cause lasting
damage,” he told Reuters Health.
The researchers analyzed medical records for adults in Ontario with
a diagnosed concussion that was not serious enough to require
hospitalization and followed them from 1992 to 2012. More than
230,000 people fell into this category.
Over an average follow-up period of nine years, 667 people who had
experienced concussions committed suicide, which is equivalent to a
rate of 31 suicides per 100,000 people per year. That’s more than
three times higher than the suicide rate in the general population,
according to the results.
In Canada there are an average of about nine suicides per 100,000
people annually, Redelmeier said.
Weekend concussions appeared to carry an even higher risk of suicide
than weekday concussions, the researchers note in CMAJ.
Weekday concussions may happen at work, where there is a treatment
protocol, but weekend concussions may be easier to shrug off without
really slowing down, Redelmeier said.
Suicide risk after a concussion increased regardless of a patient’s
past history of psychiatric conditions.
“It’s incredibly important to put these things into perspective –
the vast majority of people in this study did not die from suicide,”
“Approximately 4 to 5 million concussions occur annually (in the
U.S.),” said Craig J. Bryan of the University of Utah department of
psychology in Salt Lake City, who was not part of the new study.
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“Also, concussion appears to increase risk for sleep disturbance and
depression, and can affect decision-making processes,” Bryan told
Reuters Health by email. “All of these are risk factors for suicide
in their own right.”
The study does not prove that concussions cause some suicides, as
they may be connected in a different way, Redelmeier said.
People who suffer concussions could be predisposed to suicide
beforehand, or a concussion might cause lasting injury to neurons in
the brain that never recover, or people who suffer a concussion and
don’t take enough time to recover may be doing further damage, he
“For example, concussions are much more likely to be experienced by
individuals who drink alcohol a lot or get into fights,” Bryan said.
“Alcohol use and aggression are also risk factors for suicide.”
“If you’ve just been diagnosed with a concussion the standard
medical advice should be enforced, give yourself plenty of time to
sleep,” Redelmeier said. “Once you start feeling better, don’t try
to come back with a vengeance.”
“Once you are better, don’t forget about it entirely,” he said. “If
you had a concussion 15 years ago maybe you also want to mention it
to your physician.”
SOURCE: http://bit.ly/1Q3FF3h CMAJ, online February 8, 2016.
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