Many children with autism spectrum disorders (ASD) take psychotropic medications to treat associated symptoms of their conditions, such as irritability and anxiety. Usage has increased in recent years, and some recent studies have questioned the evidence base supporting the drugs’ effectiveness in young people with ASD.
A new study, published in a supplement to the November issue of Pediatrics, suggests that coexisting psychiatric conditions and problem behaviors might account for much of that prescribing.
The study, which examined children and teens ages 2 and 17 with autism spectrum disorders, found that 80 percent of children with a comorbid psychiatric condition were taking medication, compared to just 15 percent without any psychiatric comorbidity.
Depending on the condition in question, those with a comorbid disorder were between 5 and 17 times more likely to be taking a psychotropic medication as those without the additional disorder.
The study included 2853 children enrolled in a registry run by the Autism Treatment Network, a consortium of 17 academic medical centers in the United States and Canada that is associated with the advocacy group Autism Speaks.
The registry used DSM-IV-TR criteria and the Autism Diagnostic Observation Schedule to diagnose autistic disorder, Asperger syndrome, or pervasive developmental disorder not otherwise specified. It relied on parent reports for information about comorbid psychiatric diagnoses and medication use.
Some metaanalyses have questioned the effectiveness of treating ASD with psychiatric medications, though they have not always taken psychiatric comorbidity into account. Comorbidity is very common in autism spectrum disorders, with studies finding that between 70% and 95% percent qualify for at least one additional psychiatric diagnosis. Other researchers, however, have said these high rates partly reflect overlapping symptoms and problems with diagnostic criteria.
The Pediatrics study didn’t collect information about why the children and teens had been prescribed medication – that is, whether the meds were to treat the comorbid condition, symptoms of the ASD, or both.
However, it found that current psychotropic use was also correlated with high scores on the Child Behavior Checklist, a measure of overall problem behavior. That suggests that more troubled children are more likely to be medicated. It’s possible that children with higher scores on the checklist would also be more likely to have a comorbid psychiatric diagnosis, although this study didn’t examine the relationship between those two factors.
Previous studies have found rates of psychiatric medication use among children with ASD to range from 24% to about 80%. The authors of the Pediatrics study speculated that the relatively low overall rate of medication use in their sample – 27% – stemmed from the large number of young children enrolled in the registry. Medication use, they found, was more common in older kids, with just 1% of children under 3 receiving medication, compared with 11% of those ages 3 to 5, 46% ages 6 to 11, and 66% ages 12 to 17.
The study also found that children with sleep disorders and gastrointestinal complaints, both of which are common in children with ASD, were slightly more likely to be taking psychotropics than those without. But the difference was not nearly as marked as the finding about psychiatric comorbidity.
In addition, white children were more likely to take medications than ethnic minorities, as were those with private insurance, as compared to those with public insurance or no insurance.
ASD are far more commonly diagnosed in boys than girls, but the study found that boys and girls with ASD were prescribed medication at about the same rate. IQ didn’t correlate significantly with prescription rates, either.
The researchers noted that no medication has proved effective for the core symptoms of ASD, such as social and communication problems. Just two drugs, the antipsychotics Risperdal and Abilify, carry official FDA approval for treating irritability associated with autism in children -an umbrella term that includes aggression, severe temper tantrums, and self-injurious behavior.
Nevertheless, the authors concluded that “the evidence for the effectiveness of medications is gradually accumulating, and physician prescription of these medications to treat ASD and comorbid psychiatric conditions will likely increase over time.”