Medical and Behavioral Correlates Associated with a History of Depression in Children and Adolescents with ASD

Background: In addition to reports of rising prevalence rates of autism spectrum disorders (ASD) themselves, research suggests that ASD is associated with medical and psychiatric comorbidities at higher rates than are observed in typically developing children. Although coexisting psychiatric problems are often not the focus of treatment, research suggests that they can exacerbate the core symptoms of ASD and negatively impact a child’s functionality and quality of life. To this effect, depressive syndromes have been shown to be a particularly common and impairing comorbidity across a range of ages. 

Objectives: To identify medical and behavioral problems that are associated with a history of depressive symptomology in ASD.

Methods: A large ASD-only data set (N=4098; age 2-17 years, M=6.2, SD=3.44) from the Autism Treatment Network was divided into two groups based on caregiver endorsement of current or previous diagnoses of depression. Using ANOVA and Chi-square analyses, these groups were compared on several medical and behavioral factors. Dependent variables were operationalized with the Child Behavior Checklist and the 27-item Health and Mental Health History form. .

Results: Bivariate analysis of the data revealed significant differences in the characteristics of the Depressed (N=135) and Non-depressed (N=3963) groups. The largest effect was age, with the Depressed group being significantly older (χ² = 133.13, p< .001; Depressed M= 11.3 years, SD= 3.5; Non-Depressed M=6.0 years, SD= 3.3). The Depressed group was also more likely to have Asperger’s disorder (30% vs. 7.6% of the Non-Depressed group; χ² = 19.8, p< .001); or PDD-NOS (20.7% vs. 19.7% of the Non-Depressed group; χ² = 7.7, p= .003). Average IQ did not differ between groups. After controlling for age and within-spectrum diagnosis, the Depressed group and the Non-Depressed group significantly differed in their report of seizures and seizure disorder (χ² = 14.6, p< .001), GI problems (χ² = 25.2, p< .001), history of other psychiatric disorders (χ² = .27.29, p< .001), and self-injurious behavior and aggression (χ² = 18.63, p< .001), with the Depressed group displaying these problems at significantly higher percentages. The groups did not differ in reports of family history of depression and other psychiatric problems, eating problems, repetitive behavior, social deficits, or ADHD symptoms. For sleep problems, psychotropic medication use and history of anxiety, the Depressed and Non-Depressed groups differed significantly in the unadjusted model but not after controlling for age and diagnosis.

Conclusions: These findings suggest the existence of ASD subgroup(s) with more complicated and numerous comorbidity, versus a clear “ASD+Depression” group. This should inform studies of both depression mechanisms and treatments in ASD. In addition, the presence of these medical and behavioral problems in individuals with ASD may flag the need to screen for depressive features. Further research is needed to better define the relationship between these comorbidities and depression in ASD.