A new study has revealed a link between concussion and the risk of being diagnosed with attention-deficit hyperactivity disorder, mood and anxiety disorders, dementia and Parkinson’s disease later in life.
Despite ‘clinical recovery’ from concussion typically lasting one week, a team of researchers from the University of Manitoba suspected there may be longer term effects. They used 25 years of population-based health data between 1990 and 2015, involving almost 50,000 cases of concussion from people living in Manitoba, Canada.
They found that concussion was associated with an increased risk of being diagnosed with attention-deficit hyperactivity disorder (ADHD), mood and anxiety disorders (MADs), dementia and Parkinson’s disease.
After analysing the population data, they found that concussion was linked to an increased risk of diagnosis of ADHD, dementia and Parkinson’s.
Women who had a concussion were at greater risk of developing ADHD and MADs, but there were no differences between men and women for the risk of developing dementia or Parkinson’s.
Multiple concussions didn’t affect the risk of later being diagnosed with ADHD, but a second concussion increased the risk of dementia, while exposure to more than three concussions increased the risk of being diagnosed with MADs.
While previous studies have found links between concussion and ADHD, dementia, Parkinson’s and MADs, most have relied on patients self-reporting their symptoms, the researchers write.
However, this study can only show an association, not cause and effect.
The mechanism behind this increased risk is unknown, but the researchers state it’s possible that the pathways of some biomarkers that are dysregulated in ADHD, Mads, dementia and Parkinson’s, namely, cortisol, are also affected after a concussion.
The paper, published in the BMJ journal, states that future research is needed to explore the relationships between concussion and ADHD, MADs, dementia and Parkinson’s in other populations.
