Anticonvulsant treatment for psychiatric and seizure indications among youths

Objective: This study compared the prevalence of. anticonvulsant treatment for youths with a diagnosis of a psychiatric disorder to youths with a diagnosis of a seizure disorder. Methods: Administrative claims from outpatient visits and prescriptions were organized for a data set of 258,472 youths who were younger than 18 years of age in a mid-Atlantic state Medicaid program and were continuously enrolled in 2000. Youths dispensed an anticonvulsant were grouped into the following ICD-9 diagnostic categories: a diagnosis of a psychiatric disorder without a seizure disorder, a diagnosis of a seizure disorder without a psychiatric disorder, and a diagnosis of both a psychiatric and a seizure disorder. Anticonvulsant use was analyzed for specific diagnostic classes by age, gender, race or ethnicity, and Medicaid eligibility categories. Results: A total of 4,522 youths in the one-year data set received an anticonvulsant (1.75 percent): 3,061 had a psychiatric disorder only, 251 had a seizure disorder only, and 611 had both psychiatric and seizure disorders. Among anticonvulsant-treated youths with diagnosis information in their records (3,923 of 4,522 youths), 81 percent had a psychiatric diagnosis and 19 percent had a seizure disorder; 71 percent of those with a seizure disorder also had a psychiatric disorder. Anticonvulsant use for seizure control was proportionally greater for those younger than five years. By contrast, a vast majority of anticonvulsant users with a psychiatric diagnosis were between five and 17 years. Among anticonvulsant-treated youths with a psychiatric diagnosis, males were approximately twice as common as females. For youths with a seizure disorder, no difference was found for gender. Mood disorders and attention-deficit hyperactivity disorder were the major psychiatric diagnoses associated with anticonvulsant use. Valproic acid products were the most commonly dispensed type of anticonvulsant. Conclusions: Recent state Medicaid data reveal that youths who use anticonvulsants are far more likely to have a psychiatric diagnosis than a seizure diagnosis. Widespread off-label use of anticonvulsants for psychiatric disorders among youths warrants attention to ensure benefits and minimize risks.