National trends in pediatric use of anticonvulsants

Objective: This research study aimed to assess national trends in pediatric use of anticonvulsants for seizures and psychiatric disorders. Methods: In a cross-sectional design, data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey were analyzed. Outpatient visit information for youths (ages 0-17 years) was grouped by year for 1996-1997, 2000-2001, 2004-2005, and 2008-2009. Six of the most common anticonvulsant drugs used for psychiatric conditions were examined. Psychiatric diagnoses and seizure or convulsion diagnoses were identified with ICD-9-CM codes. The primary outcome measure was percentage prevalence of visits for anticonvulsants that included a psychiatric diagnosis as a proportion of total youth visits for an anticonvulsant. Total, diagnosis-stratified, and drugspecific visits, as well as visits for concomitant anticonvulsants and psychotropics, were analyzed. Results: As a proportion of total youth visits for anticonvulsants, visits with a psychiatric diagnosis increased 1.7 fold (p<.001), whereas the proportion of seizure-related visits did not change significantly. Regardless of diagnosis, anticonvulsant use significantly increased, from .33% to .68% of total youth visits in the 14-year period. There were significant increases in anticonvulsant use to treat pediatric bipolar disorder and disruptive behavior disorders. Visits noting divalproex decreased while visits noting lamotrigine increased among visits involving a psychiatric diagnosis. The concomitant use of stimulants and anticonvulsants significantly increased in visits noting a psychiatric diagnosis. Conclusions: Whereas anticonvulsant use for seizure disorders across the 14-year period was stable, the use of these drugs for psychiatric conditions rose to a dominant position. The growth of concomitant and off-label use to treat behavioral disorders raises questions about effectiveness and safety in community populations of youths.