Epilepsy surgery trends in the United States: Differences between children and adults

To the Editors

I was very pleased to read the recent study by Pestana Knight et al. entitled “Increasing utilization of pediatric epilepsy surgery in the United States between 1997 and 2009,” published in Epilepsia.¹ As the authors discuss, their observation of increased utilization of pediatric epilepsy surgery in the Kids' Inpatient Database (KID) is in stark contrast with our recent study utilizing the Nationwide Inpatient Sample to examine adult epilepsy surgery rates during a similar time frame.² In our study, although there was a progressive increase in the number of hospitalizations for intractable focal epilepsy in adults from 1990 to 2008, the number of resective procedures remained constant during these years, leading to an overall reduced rate of epilepsy surgery. Specifically, we did not observe a change in surgery rates after publication of the first randomized-controlled trial demonstrating the efficacy of epilepsy surgery in 2001,³ which was followed by joint guidelines recommending referral of patients with intractable seizures to a comprehensive epilepsy center.^4,5 Furthermore, our group has reported a drop in epilepsy surgeries at high-volume epilepsy centers during this time that appears to coincide with increased referrals to lower-volume hospitals that may have higher rates of perioperative complications.⁶

It would be interesting to know whether Pestana Knight and colleagues observed a similar discrepancy between surgery trends at high-volume epilepsy centers and low-volume hospitals in the pediatric population. Furthermore, their findings raise the important question of whether increasing rates of pediatric epilepsy surgery might actually contribute to the diminished number of procedures performed in adults, in that patients with childhood-onset epilepsy are receiving treatment earlier, and thus no longer need surgery by the time they reach adulthood. However, I am skeptical whether this is the case, given our own observation of increasing hospital admissions for focal epilepsy in adults,² and it would be interesting to know whether the authors similarly examined epilepsy hospitalization trends in the Kids' Inpatient Database (KID).

There is reason for optimism given the findings of Pestana Knight and colleagues, the publication of a second randomized-controlled trial demonstrating the efficacy of early resection in epilepsy,⁷ and a recent report by Haneef and colleagues demonstrating a slight trend towards earlier surgical referrals.⁸ However, surgical referrals remain significantly underutilized in both children and adults, as Pestana Knight et al. observed that the number of surgical cases was only one third of what would be expected. Furthermore, both the present study and our previous investigation found reduced utilization of surgery in racial minority patients or those without private insurance.² We must continue to educate practitioners about the increased morbidity and mortality associated with intractable epilepsy, and that focal epilepsy patients who have failed to respond to two or more antiepileptic drug regimens should be referred to an epilepsy center for comprehensive multidisciplinary evaluation.