Cognitive disengagement syndrome across attention deficit/hyperactivity disorder, autism spectrum disorder, and internalizing disorders: towards a transdiagnostic construct

Cognitive Disengagement Syndrome (CDS) refers to symptoms of fogginess, daydreaming, blank staring, and slowed behaviour. Growing evidence suggests that CDS reflects a transdiagnostic construct. This study aimed to examine (1) associations between age, sex, and CDS severity; (2) differences in CDS across Attention-Deficit/Hyperactivity Disorder (ADHD), Autism Spectrum Disorder (ASD), and internalizing disorders; and (3) associations between CDS and quality of life, as assessed by the KIDSCREEN-27. CDS was assessed in 958 clinically referred children and adolescents (mean age = 10.7 ± 2.8 years; 36.3% female) with a primary diagnosis of ADHD (n = 353), ASD (n = 494), or internalizing disorders (n = 111). Four Child Behaviour Checklist (CBCL) items (13, 17, 80, 102) were used to operationalize CDS. Analyses included ANOVAs, MANOVAs, and multiple regression analyses in the full sample and a subsample without comorbidities. CDS levels didn't differ by sex, whereas adolescents (12-17 years) showed higher CDS levels than children (6-11 years). Across diagnostic groups, ASD (M = 2.6, SD = 1.8) and internalizing disorders (M = 2.6, SD = 1.9) displayed higher CDS scores than ADHD (M = 1.8, SD = 1.6; p < .001). These findings remained significant in the subsamples without comorbidities (p < .001). Multiple regression analyses indicated that higher CDS scores were significantly associated with lower quality of life (B = -2.20, p < .001), independent of diagnostic group, sex, and age, without significant interaction between CDS and diagnosis. Correlational analyses indicated stronger associations between CDS with autistic (r = .25-.36; p < .05) and affective CBCL symptom dimensions (r = .19-.36; p < .05) dimensions than with ADHD symptoms. CDS appears to represent a clinically relevant transdiagnostic construct. Its strong expression in ASD suggests that it captures disengagement mechanisms beyond current nosological frameworks.