Adult-onset epilepsy and risk of traumatic brain injury: a nationwide cohort study

Abstract

BackgroundA knowledge gap exists regarding the risk of traumatic brain injury (TBI) in patients with epilepsy.MethodsPatients with adult-onset epilepsy during 2005–2018 in Finland were studied using retrospective longitudinal national registry-linkage design. Patients with epilepsy (n=35 686; 51% men; mean age 56.6 years) were 1:1 matched to non-epileptic controls by age, sex, comorbidity burden and cohort entry year. The primary outcome was TBI leading to admission or death, secondary outcomes were TBI admission, fatal TBI, acute neurosurgical operations (ANOs) for TBI and TBI recurrence.ResultsThe cumulative rate of the primary endpoint was 1.2% at 1 year, 5.6% at 10 years and 7.3% at 14 years in the epilepsy group versus 2.9% at 14 years in the matched controls (HR=3.77; p<0.0001). Epilepsy was associated with increased risk of TBI admission (6.9% vs 2.7%; HR=3.96; p<0.0001), ANOs (1.3% vs 0.4%; HR=7.00; p<0.0001) and fatal TBI (1.3% vs 0.5%; HR=3.82; p<0.0001), during follow-up. Competing risk analyses confirmed the association of epilepsy with all outcomes (p<0.0001). Epilepsy was associated with TBI recurrence during follow-up (HR 1.72; p=0.002).ConclusionPatients with adult-onset epilepsy have a significantly increased risk of severe and fatal TBI. The results underline the importance of TBI prevention in epilepsy.

Posttraumatic Epilepsy and Dementia Risk

“…More work is needed to determine if order of diagnosis of head injury vs seizure/epilepsy matters with regards to dementia risk; prior literature has shown a bidirectional association between head injury and epilepsy. 42 Indeed, our secondary analysis suggested that both PTE and head injury occurring after seizure/epilepsy were associated with increased dementia risk compared to head injury alone and seizure/epilepsy alone.…”

“…The pathophysiological mechanisms underlying the long-term sequelae of head injury and the development of PTE are complex, but a growing body of literature suggests that neurodegenerative mechanisms may contribute to both, providing biologic plausibility for the observed associations. More work is needed to determine if order of diagnosis of head injury vs seizure/epilepsy matters with regards to dementia risk; prior literature has shown a bidirectional association between head injury and epilepsy . Indeed, our secondary analysis suggested that both PTE and head injury occurring after seizure/epilepsy were associated with increased dementia risk compared to head injury alone and seizure/epilepsy alone.…”

Risk of epilepsy after traumatic brain injury: a nationwide Norwegian matched cohort study

“…Thus, there is a possibility that prior seizures and diagnoses of epilepsy may have been missed in the exclusion process. Since patients with epilepsy have an increased risk of TBI compared with controls ( 41 ), this might have contributed to an overestimation of epilepsy in patients with TBI versus the control group. Despite these limitations, the use of extensive nationwide registers resulting in a large sample size representing the total population of hospital-admitted patients with TBI, the use of a matched control group and the competing risk analysis, accounting for the increased risk of death among patients with TBI, ensure valid and up-to-date estimates of the cumulative incidence of PTE.…”

Seizure-Related Head Injuries: A Narrative Review

“…The underlying cause remains unclear; proposed explanations include the loss of consciousness during seizures, an atonic state, the frailty of the affected population, and antiepileptic drug side effects. TBIs in people with epilepsy are also more repetitive and more frequently fatal when compared to the population without epilepsy [19,20].…”