Polypharmacy of Psychotropic Medications May Increase the Risk of Emergency Department Visits Among Adolescents with Autism Spectrum Disorder

Background: Studies have documented high prevalence rates of using psychotropic medications to manage comorbid mental health concerns in children and adolescents with ASD, particularly older children and adolescents with ASD. It is not uncommon for physicians to prescribe multiple psychotropic medications both within and across drug classes. However, little is known about the effectiveness of polypharmacy to minimize high level service, utilization such as the Emergency Department (ED) for behavior and/or mental health crises.

Objectives: This study used a large, national healthcare claims database of a privately insured population in the US to investigate the association between prescription patterns of psychotropic medications and the incidence of ED visits for adolescents with ASD.

Methods: Using the MarketScan® database between 2005 and 2014, we designed a retrospective, longitudinal study to describe the prescription patterns of psychotropic medications (MEDs) among adolescents (aged 12-21) with ASD and potential ED visits. We identified ASD subjects as those with at least two separate diagnoses of ASD (ICD 9 codes 299.0x and 299.8x) through the entire study period. ED utilization was summarized at the individual level on a yearly basis, with the index date defined as the first ED visit date in a calendar year, or set to be July 1^st for a year without ED visits. Prescribed psychotropic MEDs within 3 months prior to the index date were documented. Other potential risk factors/confounders considered include mental health comorbidity and demographic characteristics (age, sex, etc.). Descriptive analyses and multivariable regressions were performed to estimate the effect of psychotropic MED prescriptions on ED utilization.

Results: Our study cohort consists of 63,886 ASD patients with 181,686 person-year observations (Table 1). Annually, 57.7% had ≥1 psychotropic MEDs prescribed within 3 months prior to the index date and 17.6% concurrently had ≥3 different psychotropic medications concurrently prescribed. More older adolescents were prescribed ≥ 3 MEDs (age 18-21: 19.0% ; age 15-17: 18.8%; age 12-14: 15.7%). 35% of adolescents with ASD having both internalizing and externalizing mental health comorbidities were prescribed ≥3 psychotropic MEDs, followed by those with internalizing comorbidities only (27.8%), those with externalizing comorbidities only (20.3%), and those with neither (8.9%). Multivariable logistic regression analysis showed that (Table 2), while there was essentially no increase in ED risk with prescribing 1 or 2 psychotropic MEDs, prescription of ≥3 MEDs was associated with a significantly increased risk of ED visits (adjusted Odds Ratio [95% Confidence Interval]=1.26 [1.14, 1.38] vs. 2 MEDs).

Conclusions: In this privately insured population, nearly 60% of adolescents with ASD had at least one prescribed psychotropic medication annually and 17.6% had 3 or more concurrent psychotropic MEDs within 3 months of ED utilization. Our study has provided evidence that psychotropic polypharmacy is associated with elevated risk of ED visits among adolescents with ASD. Further studies are warranted to examine whether this is reflective of greater symptom severity, more complex presentations, suboptimal medication management, under-utilization of other treatments, or some other factor(s).