We found that more than half of Medicaid-enrolled children with a diagnosis of ASD received a psychotropic medication in 2001, and >1 in 10 received ≥3 concurrently. These proportions are 5% to 10% higher than what has been reported previously in surveys of children with ASDs occurring in similar years.10–12
Use among the Medicaid population may be higher than in the general ASD population because Medicaid typically has less restrictive formulary and copayments than private insurance.32
Also, Medicaid-eligible children may be more severely affected than the general population of children with ASDs; that 70% of children in this study qualified for Medicaid because of their disability provides some evidence of this. The young children in this sample, however, had substantially higher psychotropic medication use than what has been previously reported among Medicaid-enrolled children. Zito et al33
found that 1% of Medicaid-eligible 2- to 4-year-olds were prescribed psychotropic medication; our study found proportions of 18% for 0- to 2-year-olds and 32% for 3- to 5-year-olds. In addition, psychotropic medication use among this sample was ~5 times higher than what has been reported for Medicaid-eligible children in general34
and 2.5 times higher than what has been reported for Medicaid-eligible children who use mental health services.35
White children were more likely than children in any other ethnic or racial group to use medications, similar to what previous studies have reported regarding psychotropic medication use in general.34,36,37
Although this issue has not been examined in ASDs, studies of children with attention-deficit/hyperactivity disorder suggest that differences may be attributable to disparities in access to health care, beliefs about adverse effects of medication, and general trust of the health care system.38,39
The finding that children who were eligible for Medicaid because of disability were more likely to use medication than children who were eligible because of poverty is not surprising and is in line with previous research40
; more concerning is the high prevalence of psychotropic medication and multiple medication use among children in foster care. Because difficult behavior is associated with placement changes in foster care, child welfare systems may attempt to reduce behavioral difficulties with medication to increase placement stability.41
Because children with ASDs are often quite averse to changes in routine, foster placement may be even more disruptive to them than to other children. Alternatively, children in foster care may have less access to behavioral programs, resulting in greater psychotropic medication use to control behaviors.
Hospitalizations, high volume of ASD-related medical services, and the presence of other psychiatric diagnoses, all of which were associated with psychotropic medication use, may be indicators of clinical complexity, which would also explain the very high percentages of multiple medication use among children who had an inpatient stay or who were assigned 1 of these diagnoses, yet among those without any other psychiatric diagnosis, use was still nearly 40%.
The significant associations with county characteristics reveal that socioeconomics and local health system factors drive medication use as much as the needs of individual children. Children in counties with greater urban density had lower proportions of medication use. Similarly, Palmer et al22
showed that greater urban density at the county level was associated with more identification of children with ASD. Urban areas, as well as areas with a higher proportion of white residents, may have access to academic health settings where there is greater familiarity with developmental delays. Alternatively, with greater access to health care resources, less severe cases may be more likely to be diagnosed, thereby resulting in a Medicaid-eligible group of children who are less in need of medication.
Interpretation of study findings is limited by a number of factors, primary among them that the autism diagnosis in Medicaid claims has not been validated. Although its accuracy has not been specifically examined, Fombonne et al42
found 97% positive predictive value for chart diagnoses and a diagnosis of autism administered by a trained research team, and Yeargin-Allsopp et al43
found that 98% of children with a chart diagnosis met research criteria for ASD. Similarly, there were no measures of symptoms or severity, both of which are most likely associated with psychotropic medication use. A third limitation is that states have different coding strategies and incentives for providers to submit claims. Differences, for example, in whether psychotropic medications are covered under capitated or fee-for-service plans may affect claim submission. Although this may affect the observed overall proportions, it is unlikely to affect the odds ratios associated with the logistic regression, because clustering at the county and state levels was accounted for in the analysis. A fourth limitation is the absence of other variables at the child level (eg, age of diagnosis, use of behavioral interventions) and county level (eg, ASD-specific intervention resources) that may relate to medication use. Finally, the study was conducted with Medicaid-eligible children and may not be generalizable to other children, although children with ASDs are disproportionately Medicaid eligible relative to those with other disabilities.44–46
In addition, Medicaid is the most important insurer of children in the United States, covering >1 in 4 children.47
Despite these limitations, these findings have important implications. The high levels of use of many different psychotropic agents, often in combination, is concerning, especially among young children, in whom the effects of these medications on development have not been well studied.33,48
Especially worthy of additional study is sedative use among very young children, which may be associated with the sleep problems that often accompany autism49
or may be associated with medical procedures.50
There also is little systematic evidence for the use of psychotropic medications in combination.51
These issues speak to the importance of scientific studies’ keeping pace with practice. Although traditional randomized trials may not be feasible or ethical, careful naturalistic studies of the risks, benefits, and costs of psychotropic medication use in children with ASDs are warranted.52
The association of health care resources with psychotropic medication use suggests the potential of under-resourced communities and the need for more and well-trained pediatric primary care and specialist clinicians who can accurately diagnose ASDs and appropriately treat children with ASDs. Finally, the results suggest the potential importance of local and regional policies and practices. Variation in state and county approaches and resulting service use offers an important opportunity for study and the potential to develop local and national models that maximize the safety, efficiency, and effectiveness of care that is delivered to children with ASDs.