In hospitalized children with autism spectrum disorder (ASD), predictors of comorbid attention-deficit/hyperactivity disorder (ADHD) included male sex, adolescent age, White race, and longer hospital stay, according to study results presented at Psych Congress 2020 Virtual Experience, held online from September 11 to 13, 2020.

This retrospective study analyzed hospital admission records comprising 3095 cases of ASD obtained from the Healthcare Cost and Utilization Project’s Nationwide Inpatient Sample. The data range for inclusion in the analysis was January 2012 to January 2014. Approximately 32.5% (n=1005) of the cases reported a co-diagnosis of ADHD

Boys were found to have a significantly higher odds of comorbid ADHD compared with girls (odds ratio [OR], 2.2; 95% CI, 1.741-2.749; P <.001). Adolescents between the ages of 12 and 18 years were more likely to have ADHD compared with those aged <11 years (58.7% vs 41.3%, respectively). A higher prevalence of comorbid ADHD was also found in White patients (66.7%) compared with those of African American (16.4%), Hispanic (11.4%), and Asian (2.5%) descent. Patients with ASD and comorbid ADHD were mostly from the South (30.8%) and Midwest (29.9%).

Psychosis was reported in a significantly higher proportion of patients with ADHD compared with patients without ADHD (37.3% vs 24.9%, respectively; OR, 1.762; 95% CI, 1.485-2.090; P <.001). Additionally, patients with ADHD had a longer hospital stay (9.2 ± 9.319 vs 7.9 ± 11.971 days). Comorbid ADHD with ASD increased the length of hospital stay by 0.9 days, whereas comorbid depression increased length of stay by 2.1 days. Conversely, comorbid drug use was associated with a 6-day decrease in hospital length of stay.

Limitations of the study include the use of an administrative database that lacks patient-level data, as well as reliance on diagnostic codes for the identification of patients with ASD.

Patel R, Ashraf S. Predictors of co-diagnosis of attention-deficit/hyperactivity disorder in children with autism spectrum disorder. Presented at: Psych Congress 2020 Virtual Experience; September 10-13, 2020. Poster 190.