Incidence and risk factors of posttraumatic seizures following traumatic brain injury: A Traumatic Brain Injury Model Systems Study

Abstract

SUMMARYObjective: Determine incidence of posttraumatic seizure (PTS) following traumatic brain injury (TBI) among individuals with moderate-to-severe TBI requiring rehabilitation and surviving at least 5 years. Methods: Using the prospective TBI Model Systems National Database, we calculated PTS incidence during acute hospitalization, and at years 1, 2, and 5 postinjury in a continuously followed cohort enrolled from 1989 to 2000 (n = 795). Incidence rates were stratified by risk factors, and adjusted relative risk (RR) was calculated. Late PTS associations with immediate (<24 h), early (24 h-7 day), or late seizures (>7 day) versus no seizure prior to discharge from acute hospitalization was also examined. Results: PTS incidence during acute hospitalization was highest immediately (<24 h) post-TBI (8.9%). New onset PTS incidence was greatest between discharge from inpatient rehabilitation and year 1 (9.2%). Late PTS cumulative incidence from injury to year 1 was 11.9%, and reached 20.5% by year 5. Immediate/early PTS RR (2.04) was increased for those undergoing surgical evacuation procedures. Late PTS RR was significantly greater for individuals who self-identified as a race other than black/white (year 1 RR = 2.22), and for black individuals (year 5 RR = 3.02) versus white individuals. Late PTS was greater for individuals with subarachnoid hemorrhage (year 1 RR = 2.06) and individuals age 23-32 (year 5 RR = 2.43) and 33-44 (year 5 RR = 3.02). Late PTS RR years 1 and 5 was significantly higher for those undergoing surgical evacuation procedures (RR: 3.05 and 2.72, respectively).

Epileptiform activity in traumatic brain injury predicts post‐traumatic epilepsy

“…2 PTE rates are reported in up to 20% of patients, with increased risk based on brain injury severity, surgical intervention, time since traumatic brain injury (TBI), and younger age. [3][4][5][6] Although some risk factors are known, we need to better stratify patients at highest risk for PTE to better understand antiepileptogenesis and develop therapeutic agents. Although there is great interest in interventions to prevent post-TBI epileptogenesis, clinical trials have been plagued by financial and logistical barriers, with estimates upward of $20 million.…”

A testbed for optimizing electrodes embedded in the skull or in artificial skull replacement pieces used after injury

“…Being able to monitor brain health and the development of seizure activity is particularly useful after a traumatic brain injury 2,3 . After injury, putting electrodes, such as ECoG arrays, within the cranial cavity could potentially compound the injury by causing additional irritation and damage 4 .…”

“…The ability to chronically monitor brain health and watch for epileptic activity development would be quite useful after brain trauma or surgery 2,3 . However, continuous brain monitoring via scalp surface electroencephalograms (EEGs) can be cumbersome and impractical outside of the clinical setting and may not be possible if the skin is not healthy enough after injury to safely apply the electrodes.…”

State of the Art: Novel Applications for Deep Brain Stimulation

“…Post‐traumatic seizures are an important complication of head injury, and can be classified as immediate (occurring within 24 hours of injury), early (occurring between 24 hours and one week of injury), or late (occurring more than 7 days following injury). Late post‐traumatic seizures are often taken to indicate the presence post‐traumatic epilepsy . In a large US epidemiological study, the five‐year cumulative incidence of post‐traumatic seizures was reported to be 0.7, 1.2, and 10% in mild, moderate and severe head injuries respectively and more recent studies have reported the cumulative prevalence of post‐traumatic seizures to range between 4 and 20.5% .…”

“…Late post‐traumatic seizures are often taken to indicate the presence post‐traumatic epilepsy . In a large US epidemiological study, the five‐year cumulative incidence of post‐traumatic seizures was reported to be 0.7, 1.2, and 10% in mild, moderate and severe head injuries respectively and more recent studies have reported the cumulative prevalence of post‐traumatic seizures to range between 4 and 20.5% . Following traumatic brain injury, the risk of developing epilepsy may be as much as 30 times higher than in the general population, and the majority of patients who develop post‐traumatic epilepsy after TBI have drug‐resistant epilepsy, which means that they fail to respond to an adequate trial of more than two appropriately selected anti‐epileptic drugs .…”