Psychopharmacotherapy use and adherence in autism spectrum disorders

More than half of children diagnosed with an autism spectrum disorder (ASD) use medication to manage ASD-associated aberrant behaviors. However, obtaining a diagnosis can be difficult, leaving many children undiagnosed and so not included in previous medication studies. Additionally, research in this area is limited by parent recall, volunteer participation, and lacks a quantitative medication adherence measure, an important predictor of treatment outcome. The goal of this project was to quantify medication use and adherence in children who met ASD diagnostic criteria by linking South Carolina population-based surveillance data from 2000 to 2008 with Medicaid for a detailed demographic, behavioral, educational, and medical history.;First, medication use among 8- and 15-year olds with ASD in 2006 or 2007 was quantified. Forty percent used psychotropics, and 20% used multiple psychotropic classes. Common combinations were attention deficit hyperactivity disorder (ADHD) medications and an antihypertensive, antidepressant or antipsychotic; and antidepressants and antipsychotics. The number of prescriptions and medication costs varied by age. Second, we assessed demographic, behavioral, and medical predictors of polypharmacy among 8-year old children between 2000 and 2008. Of children with any psychotropic prescription claim, 153 (41%) used interclass polypharmacy overlapping 30 days or more. The most common combinations were attention deficit hyperactivity disorder (ADHD) medications and an antidepressant, antipsychotic, or a mood stabilizer. Black children, those eligible for Medicaid due to income, and those with ASD-diagnostic communication deficits had significantly lower odds of polypharmacy, while children with aberrant behaviors and conduct disorders had higher odds. Lastly, adherence rates were calculated using the validated Proportion of Days Covered (PDC) and predictors of adherence were identified. Rates were low for ADHD medications (44%), antidepressants (40%) and antipsychotics (52%). Aberrant behaviors, co-occurring conditions, and the medication regimen complexity index were the strongest predictors of adherence.;This study has significant implications for routine prescribers and developing clinical trials; low adherence rates highlight the importance of addressing adherence, as, regardless of biomedical advances, no treatment can yield optimal outcomes if not taken properly. Identifying barriers to adherence will guide targeted interventions to ultimately improve treatment outcomes.