The atypical antipsychotic medication risperidone (Risperdal) does not negatively affect cognitive skills of children with autism, and may lead to improvements, according to an NIMH-funded study published recently in the Journal of Child and Adolescent Psychopharmacology. Risperidone is prescribed for children with autism to treat aggression, self-harming behavior and other serious behavioral problems.
Antipsychotics often cause sedation or drowsiness, especially in the first weeks of treatment, but it is not clear if they also blunt or impair cognitive functioning. Results of other studies have been mixed, and few studies have been conducted on children with autism spectrum disorder, a developmental disorder that can cause severe and pervasive impairments in thinking, feeling, language, and the ability to relate to others.
In the new study, Michael Aman, Ph.D., of the Ohio State University, and colleagues randomly assigned 38 children ages five to 17 to either risperidone or placebo (sugar pill) for an eight-week period. All of the children had autism spectrum disorder and serious behavior problems.
The children were assessed at the beginning of the study, at four weeks and at eight weeks to determine changes in their cognitive skills. Aman and colleagues found that most of the children taking risperidone responded to medication. The children showed significantly improved cognitive skills in aspects of attention and memory. There was no change in some skills, such as hand-eye coordination and simple math. An earlier report indicated that risperidone also was associated with reduced irritability, disruptive behavior and hyperactivity.1 Aman and colleagues suggested that this calming effect may have enabled the participants to perform better on the assessments.
The researchers caution that the study's implications are limited because so many of the initial participants were unable to complete the study. Initially, 101 children were enrolled in the study, but many were determined to be too severely impaired by their illness or too disruptive in their behavior to be adequately assessed. The 38 final participants tended to be older and to have higher IQs than the children who did not complete the study. Still, risperidone was associated with some important gains in cognitive skills and no indications of functional loss. Additional research is needed to determine the extent to which risperidone may improve cognitive skills in children with autism, said the authors.
Clinicians can be reassured that prescribing risperidone to children with autism likely will not harm cognitive skills, but the authors recommend prescribing with caution because the medication is still associated with potentially serious metabolic side effects.
Aman MG, Hollway JA, McDougle CJ, Scahill L, Tierney E, McCracken JT, Arnold LE, Vitiello B, Ritz L, Gavaletz A, Cronin P, Swiezy N, Wheeler C, Koenig K, Ghuman JK, Posey DJ. Cognitive effects of risperidone in children with autism and irritable behavior. Journal of Child and Adolescent Psychopharmacology. 2008 Jun; 18(3): 227-236.
1Research Units on Pediatric Psychopharmacology Autism Network. Risperidone in children with autism and serious behavioral problems. The New England Journal of Medicine. 2002 Aug 1; 347(5): 314-321.