Mild TBI May Increase Risk for Parkinson Disease
The Parkinson-affected neuron on the left produces a very low level of dopamine compared with the normal neuron on the right. Image credit: Carol and Mike Werner/Science Source
HealthDay News — Mild traumatic brain injury (TBI) is associated with increased risk of Parkinson disease (PD) among military veterans, according to a study published online April 18 in Neurology.
Raquel C. Gardner, M.D., from the University of California, San Francisco, and colleagues conducted a retrospective cohort study involving all patients with a TBI diagnosis in Veterans Health Administration databases from October 2002 to September 2014, age-matched to a random sample of patients without TBI in a 1:1 ratio. Participants were aged 18 years and older and had no PD or dementia at baseline. In models adjusted for demographics and medical/psychiatric comorbidities, the risk of PD after TBI was assessed.
The researchers found that 1,462 patients from the overall cohort of 325,870 patients were diagnosed with PD during follow-up. Participants with TBI had an increased incidence of PD compared to those with no TBI (no TBI, 0.31 percent; all-severity TBI, 0.58 percent; mild TBI, 0.47 percent; moderate-severe TBI, 0.75 percent). All-severity TBI, mild TBI, and moderate-severe TBI were associated with increased PD risk in adjusted models (hazard ratios, 1.71, 1.56, and 1.83, respectively).
"This study highlights 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," the authors write.