Levetiracetam vs phenytoin prophylaxis in severe traumatic brain injury: Systematic review and meta-analysis

Antiseizure Medications in Adult Patients With Traumatic Brain Injury: A Systematic Review and Bayesian Network Meta-Analysis

OBJECTIVES

We sought to evaluate the effectiveness of any antiseizure medication on the incidence of early post-traumatic seizures among adult patients with traumatic brain injury.

DATA SOURCES

MEDLINE, Embase, PubMed, Cochrane Central Register of Controlled Trials, and LILACS were searched from inception to October 2023.

STUDY SELECTION

We included randomized trials of adult patients with traumatic brain injury evaluating any antiseizure medication compared with either placebo or another agent.

DATA EXTRACTION

Two reviewers independently extracted individual study data and evaluated studies for risk of bias using the Cochrane Risk of Bias tool. Our main outcome of interest was the occurrence of early seizures (i.e., within 7 d); secondary outcomes included late-seizures and all-cause mortality.

DATA SYNTHESIS

Bayesian network meta-analyses were used to derive risk ratios (RRs) alongside 95% credible intervals (CrIs). We used Grading of Recommendations Assessment, Development, and Evaluation methodology to rate the certainty in our findings. Overall, ten individual randomized controlled trials (1851 participants) were included. Compared with placebo, phenytoin (RR, 0.28; 95% CrI, 0.13-0.57; moderate certainty) and levetiracetam (RR, 0.20; 95% CrI, 0.07-0.60; moderate certainty) were associated with a reduction in the risk of early seizures. Carbamazepine may be associated with a reduced risk of early seizures, but the evidence is very uncertain (RR, 0.41; 95% CrI, 0.12-1.27; very low certainty). Valproic acid may result in little to no difference in the risk of early seizures, but the evidence is very uncertain (RR, 0.97; 95% CrI, 0.16-9.00; very low certainty). The evidence is very uncertain about the impact of any antiseizure medication on the risk of late seizures or all-cause mortality at longest reported follow-up time.

CONCLUSIONS

Phenytoin or levetiracetam reduce the risk of early seizures among adult patients with traumatic brain injury. Further research is needed to evaluate required duration of therapy and long-term safety profiles.

Levetiracetam dosing for seizure prophylaxis in neurocritical care patients

BACKGROUND/OBJECTIVE

Levetiracetam is used for seizure prophylaxis in patients presenting with subarachnoid hemorrhage (SAH) or traumatic brain injury (TBI). We aim to characterize the optimal levetiracetam dosage for seizure prophylaxis.

METHODS

This retrospective cohort study included adult patients at an academic tertiary hospital presenting with SAH or TBI who received levetiracetam at a total daily dose (TDD) equivalent to or greater than 1000 mg. The primary outcome was combined seizure incidence, including clinical and subclinical seizures.

RESULTS

We identified 139 patients (49.6% male, mean age 53 years) for inclusion. For patients receiving a 1000-mg TDD, the administration was 500 mg twice daily. For patients receiving >1000-mg TDD, 77/78 patients received 1000 mg twice daily and one patient received 750 mg twice daily. Patients receiving 1000-mg TDD had a higher seizure incidence than those receiving >1000-mg TDD (p = 0.01), despite no difference in examined confounders, including history of alcoholism (p = 0.49), benzodiazepine use (p = 0.28), or propofol use (p = 0.17). No difference in adverse effects was observed (anemia, p = 0.44; leukopenia, p = 0.60; thrombocytopenia, p = 0.86).

CONCLUSIONS

Patients may experience a reduced incidence of clinical and electroencephalographic seizures with levetiracetam dosing >1000-mg TDD.

Current Clinical Trials in Traumatic Brain Injury

Traumatic brain injury (TBI) is one of the leading causes of morbidity, disability and mortality across all age groups globally. Currently, only palliative treatments exist, but these are suboptimal and do little to combat the progressive damage to the brain that occurs after a TBI. However, multiple experimental treatments are currently available that target the primary and secondary biochemical and cellular changes that occur after a TBI. Some of these drugs have progressed to clinical trials and are currently being evaluated for their therapeutic benefits in TBI patients. The aim of this study was to identify which drugs are currently being evaluated in clinical trials for TBI. A search of ClinicalTrials.gov was performed on 3 December 2021 and all clinical trials that mentioned “TBI” OR “traumatic brain injury” AND “drug” were searched, revealing 362 registered trials. Of the trials, 46 were excluded due to the drug not being mentioned, leaving 138 that were completed and 116 that were withdrawn. Although the studies included 267,298 TBI patients, the average number of patients per study was 865 with a range of 5–200,000. Of the completed studies, 125 different drugs were tested in TBI patients but only 7 drugs were used in more than three studies, including amantadine, botulinum toxin A and tranexamic acid (TXA). However, previous clinical studies using these seven drugs showed variable results. The current study concludes that clinical trials in TBI have to be carefully conducted so as to reduce variability across studies, since the severity of TBI and timing of therapeutic interventions were key aspects of trial success.