Abstracts

Rationale: Children with epilepsy have a common need of psychotropic treatment for psychiatric comorbidities, such as attention deficit / hyperactivity disorder (ADHD), depression, anxiety or psychosis. However, a large number of psychotropic drugs have a proconvulsant potential, which may worsen seizure control. Drug utilization studies including psychotropics other than anticonvulsant drugs (AEDs) in children with epilepsy are scarce and most are conducted outside the US. Detection of prominent treatment pattern could inform the research agenda concerning drug safety and efficacy of psychotropic regimen.Methods: We used Medicaid Analystic eXtract (MAX) data including billing data for pharmacy, in- and outpatient encounters in 29 US states from 1999 to 2010 to describe psychotropic drug utilization in children with epilepsy. Children aged 3-18 with at least two outpatient visits with diagnosis of epilepsy (ICD-9-CM 345.xx) at least 30 days apart but within 2 years or 1 inpatient visit with epilepsy were included in this study. We followed the patients for 1 year to describe the prevalence of select psychotropic drug use other than AEDs, and for 2 years to describe the prevalence of psychotropic polypharmacy, respectively. We measured psychotropic drug utilization from pharmacy claims using NDC codes to identify active ingredients, prescription fill date and pharmacy-recorded dispensed days' supply.Results: The most commonly used non-AED psychotropic drugs in children with epilepsy were ADHD drugs, including stimulants and alpha agonists. The prevalence of amphetamine use ranged from 4.4% to 9.0% across the 11 years follow-up; methylphenidate from 7.4% to 9.8% and clonidine from 6.7% to 8.8%. Other prevalent psychotropics included risperidone (range: 6.1% - 9.1%) as the most commonly used antipsychotic; diphenhydramine (range: 4.3% - 6.1%), hydroxyzine (range: 2.8% - 3.8%) and pyrilamine (range: 1.6% - 3.6%) were the most commonly used anxiolytics/hypnotics/sedatives; and fluoxetine (range: 1.7% - 2.2%) and sertraline (range: 2.1% - 3.2%) were the most commonly used antidepressants. About 10% - 15% of children with epilepsy had at least one episode of concomitant use of 2 psychotropic drugs during the 2-year follow-up from 1999-2001 to 2008-2010. The prevalence of the top psychotropic polypharmacy regimen excluding AEDs were all below 2% and included amphetamine + clonidine, amphetamine + risperidone, clonidine + aripiprazole, clonidine + methylphenidate, clonidine + risperidone, and methylphenidate + risperidone. The prevalence of psychotropic polypharmacy excluding AEDs increased steadily from 12.0% in 1999-2001 to a peak of 15.2% in 2005-2007 and declined slightly thereafter to 14.8% in 2008-2010.Conclusions: The use of psychotropic drugs other than AEDs in children with epilepsy covered by Medicaid programs is prevalent and growing, with the most prevalent use involving ADHD drugs, antipsychotics, anxiolytics/hypnotics/sedatives and antidepressants. The impact of these drugs on seizure control should be further investigated.