Researchers used conditional logistic regression to evaluate nine variables.
Neurology Reviews. 2018 February;26(2):35
WASHINGTON, DC—In a pediatric epilepsy population, number of antiepileptic drugs (AEDs) used and prior epilepsy surgery may predict sudden unexpected death in epilepsy (SUDEP), according to a study presented at the 71st Annual Meeting of the American Epilepsy Society.
Kishore Vedala, a medical student at the Medical College of Georgia at Augusta University, and colleagues sought to develop a predictive model for at-risk pediatric patients by conducting a matched case–control study.
Using records from the Medical College of Georgia, the researchers identified 11 SUDEP cases that occurred between 2007 and 2017. They compared the cases with 53 controls matched for age, epilepsy duration, and gender. The researchers used a conditional logistic regression model to evaluate the following nine potential predictor variables: mental retardation, seizure frequency, seizure type, prior status epilepticus, number of AEDs, prior epilepsy surgery, vagus nerve stimulator therapy, seizure progression, and awake interictal heart rate variability. They identified the optimum predictor models using Akaike’s information criterion and evaluated model performance using receiver operating characteristic area under the curve (AUC).
Prior status epilepticus (ie, having had a seizure that lasted longer than five minutes), prior epilepsy surgery, and having received three or more AEDs at the same time were significant predictors of SUDEP (odds ratios, 7.83, 4.23, and 4.7, respectively), whereas the other variables were not. The best model used number of AEDs and prior epilepsy surgery (AUC, 0.855). The second-best model used number of AEDs and prior status epilepticus (AUC, 0.839). The third-best model used number of AEDs alone (AUC, 0.807).
Yong Park, MD
The risk factors likely reflect epilepsy that is difficult to control. Many of the patients who underwent surgery continued to have frequent seizures, which suggests that unsuccessful surgery might increase SUDEP risk through unknown mechanisms, the researchers said. Although surgery and number of medications were associated with increased SUDEP risk, this finding “does not mean that people with epilepsy should not continue with those treatments, which may be key to helping control seizures and improving quality of life,” said Yong Park, MD, senior author of the study and Professor and Chair of Child Neurology at Medical College of Georgia at Augusta University. “Rather, our findings help identify those who may be at high risk and should be watched closely, such as by being monitored at night when SUDEP is most likely to occur.”