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Mild TBI and Risk of Parkinson Disease

Neurology; ePub 2018 Apr 18; Gardner, et al

Among military veterans, mild traumatic brain injury (mTBI) is associated with 56% increased risk of Parkinson disease (PD), even after adjusting for demographics and medical/psychiatric comorbidities, according to a recent study. Therefore, it’s crucial for clinicians to understand the importance of TBI prevention, long-term follow-up of TBI-exposed veterans, and the need to determine mechanisms and modifiable risk factors for post-TBI PD. Researchers identified all patients with a TBI diagnosis in Veterans Health Administration databases from October 2002 to September 2014 and age-matched 1:1 to a random sample of patients without TBI. All patients were aged ≥18 years without PD or dementia at baseline. Researchers found:

  • Among 325,870 patients (half with TBI; average age 47.9 ± 17.4 years; average follow-up 4.6 years), 1,462 were diagnosed with PD during follow-up.
  • Compared to no TBI, those with TBI had higher incidence of PD (no TBI 0.31%, all-severity TBI 0.58%, mTBI 0.47%, moderate-severe TBI 0.75%).
  • In adjusted models, all-severity TBI, mTBI, and moderate-severe TBI were associated with increased risk of PD: all-severity TBI 1.71; mTBI 1.56; and moderate-severe TBI 1.83.


Gardner RC, Byers AL, Barnes DE, Li Y, Boscardin J, Yaffe K. Mild TBI and risk of Parkinson disease. A Chronic Effects of Neurotrauma Consortium Study. [Published online ahead of print April 18, 2018]. Neurology. doi:10.1212/WNL.0000000000005522.