Therapeutic Horseback Riding for Youth With Autism and Psychiatric Comorbidities: A Randomized Trial

OBJECTIVE Autism spectrum disorder care is often complicated by co-occurring psychiatric symptoms. Equine-assisted services show promise for improving behavioral outcomes in this population. We aimed to examine benefits of equine-assisted services for youth with autism at higher risk for mental health interventions. METHODS A total of 236 youth with autism and psychiatric comorbidity (aged 6–16 years.) were enrolled in a randomized controlled multisite clinical trial, stratified by nonverbal IQ, and assigned to 1 of 3 intervention arms: therapeutic horseback riding (THR), no horse contact barn activity (BA), or waiting period followed by a BA/THR hybrid. Caregivers completed outcome measures. Speech outcomes were evaluated by blinded raters. Intervention methods expand those from a previous efficacy trial. RESULTS Intent-to-treat analyses with 169 participants completing at least 1 intervention lesson revealed that compared with the waitlist control (n = 28), both THR (n = 74) and BA (n = 67) interventions showed clinically significant reductions in co-primary outcomes of irritability (P < .0001; THR effect size d = 1.15; BA effect size d = 1.04) and hyperactivity (THR P < .0001, effect size d = 1.06; BA P = .005, effect size d = 0.68). The THR group showed significantly greater reductions in hyperactivity compared with the BA group (P = .03; effect size d = 0.39) beginning at intervention week 4. Additional significant improvements in THR and BA groups vs the waitlist control were seen in emotional regulation and social behaviors. CONCLUSIONS Equine-assisted activities are an effective intervention to address behavior challenges in youth with autism and psychiatric comorbidity; THR may offer additive reductions in hyperactivity.