Systematic Review and Meta-analysis: Efficacy of Pharmacological Interventions for Irritability and Emotional Dysregulation in Autism Spectrum Disorder and Predictors of Response

Objective: Emotional dysregulation and irritability are common in individuals with autism spectrum disorder (ASD). We conducted the first meta-analysis assessing the efficacy of a broad range of pharmacological interventions for emotional dysregulation and irritability in ASD and predictors of response.Method: Following a preregistered protocol (PROSPERO: CRD42021235779), we systematically searched multiple databases until January 1, 2021. We included placebo-controlled randomized controlled trials (RCTs) and evaluated the efficacy of pharmacological interventions and predictors of response for emotional dysregulation and irritability. We assessed heterogeneity using Q statistics and publication bias. We conducted subanalyses and meta-regressions to identify predictors of response. The primary effect size was the standardized mean difference. Quality of studies was assessed using the Cochrane Risk of Bias Tool (RoB2).Results: A total of 2,856 individuals with ASD in 45 studies were included, among which 26.7% of RCTs had a high risk of bias. Compared to placebo, antipsychotics (standardized mean difference = 1.028, 95% CI = 0.824-1.232) and medications used to treat attention-deficit/hyperactivity disorder (ADHD) (0.471, 0.061-0.881) were significantly better than placebo in improving emotional dysregulation and irritability, whereas evidence of efficacy was not found for other drug classes (p > .05). Within individual medications, evidence of efficacy was found for aripiprazole (1.179, 0.838-1.520) and risperidone (1.074, 0.818-1.331). Increased rates of comorbid epilepsy (b = -0.049, p = .026) were associated with a lower efficacy.Conclusion: Some pharmacological interventions (particularly risperidone and aripiprazole) have proved efficacy for short-term treatment of emotional dysregulation and irritability in ASD and should be considered within a multimodal treatment plan, taking into account also the tolerability profile and families' preferences.