Mapping the association between cognitive disengagement syndrome and internalizing disorders: A systematic scoping review with meta-analysis and meta-regression.

Cognitive Disengagement Syndrome (CDS), previously known as Sluggish Cognitive Tempo, has increasingly been recognized as a construct distinct from ADHD inattention yet strongly associated with internalizing disorders. This scoping review synthesized evidence from 82 studies published between 2002 and 2025, combining narrative synthesis with three-level meta-analysis and meta-regression. Across healthy and clinical samples, individuals with elevated CDS consistently showed higher rates of depression and anxiety, with more than one-third reaching clinical thresholds. Associations remained significant after controlling for ADHD inattention and were observed in children, adolescents, and adults. Longitudinal evidence suggested that CDS may operate as a developmental risk factor for later depression, though findings for anxiety were less consistent. Despite robust evidence of comorbidity, very few studies examined the functional consequences of CDS-internalizing overlap, and none employed analytic strategies to address symptom overlap, despite substantial phenomenological similarities. Meta-analyses confirmed moderate-to-strong associations, with the strongest link for depression (r = 0.56), followed by anxiety (r = 0.46) and broader internalizing symptoms (r = 0.44). Meta-regression identified depression as a significant moderator and revealed inflated effect sizes in same-informant studies, while demographic factors such as age, sex, population type, and sample size did not significantly account for variability. These findings support the conceptualization of CDS as a structurally distinct yet transdiagnostic construct, particularly tied to depressive symptomatology. However, methodological limitations, including scarce longitudinal and multi-informant studies, lack of symptom-overlap controls, and limited evidence on functional outcomes, constrain clinical interpretation and highlight the need for more rigorous, developmentally informed research.