Bidirectional association found between TBI, neurological diagnoses

There is a bidirectional association between traumatic brain injury (TBI) and certain neurological conditions, according to a study published online June 17 in Neurology.

Carrie Peltz, Ph.D., from the Northern California Institute for Research and Education in San Francisco, and colleagues conducted a retrospective cohort study involving veterans age 55 and older who received care at U.S. Veterans Health Affairs facilities and had acute TBI. Participants with TBI were matched to non-TBI controls (13,801 and 41,403, respectively). Incident stroke, Parkinson disease (PD), epilepsy and dementia were determined one year before and after TBI in the TBI cohort and during a two-year period in the non-TBI cohort.

The researchers found that compared with the non-TBI cohort, veterans with TBI had higher incidence rates of the four conditions before TBI (incidence rate ratios, 3.2, 3.1, 3.0 and 4.4 for stroke, dementia, PD and epilepsy, respectively). After adjustment for comorbidities and health care utilization, results were slightly attenuated but remained significant. For veterans with TBI, incidence rates were higher in the one year after TBI compared with the pre-TBI period, with significantly higher rates of incident stroke, epilepsy and dementia (incidence rate ratios, 1.83, 2.29 and 1.24, respectively), while rates of PD did not differ significantly.

“These findings suggest that the period after being diagnosed with a neurological condition is an important time period for preventing TBI,” Peltz said in a statement. “Our findings raise the possibility that dementia, stroke, epilepsy and Parkinson’s disease are themselves risk factors for TBI in older people. Neurological diseases often impair motor control, balance, gait, coordination and thinking skills—all of which make people more likely to fall, which is the main cause of TBI in older adults.”

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