Psychiatric comorbidity associated with co-occurring autism spectrum disorder and substance use disorder

Background: Although both autism spectrum disorder (ASD) and substance use disorder (SUD) are both commonly comorbid with other psychiatric conditions, there is a paucity of research on the overlap of these disorders. The primary aim of the present study was to identify the prevalence of psychiatric comorbidities in young adults with SUD and ASD compared to those with ASD only. Method: Multivariate logistic regression controlling for age was used to compare the prevalence of psychiatric disorders in a sample of treatment-seeking adult outpatients with a) ASD without SUD and b) ASD with SUD. Psychiatric and SUD diagnoses were determined by semi-structured interview (SCID for DSM IV). Results: The sample included 42 patients with ASD only (mean age +/- SD = 26.2 +/- 8.9 years) and 21 with ASD and SUD (35.2 +/- 12.6). High rates of psychopathology were found in both groups. Comorbid conduct disorder (CD) was significantly more prevalent in the ASD + SUD group (25 %) compared to those without SUD (5%; p < 0.05). There were no other significant differences between groups in the rates of non-conduct comorbid psychopathology. Conclusion: In both groups, rates of psychopathology were high with CD being significantly more common in young adults with ASD and SUD. These findings highlight the importance of screening for CD in individuals with ASD to mitigate the potential development of comorbid SUD. Further research is needed to determine if CD is a true risk factor for SUD in the ASD population and identify other risk factors.

Automated summary

This study compared the prevalence of psychiatric comorbidities in young adults with autism spectrum disorder (ASD) and substance use disorder (SUD) to those with ASD only, finding high rates of psychopathology in both groups. Conduct disorder (CD) was significantly more prevalent in the ASD + SUD group, highlighting the importance of screening for CD in individuals with ASD to mitigate the potential development of comorbid SUD. Further research is needed to determine CD as a true risk factor for SUD in the ASD population and identify other risk factors.