Epidemiology and Cognitive Function in Adults with ADHD and Cognitive Disengagement Syndrome

Background Attention-Deficit/Hyperactivity Disorder (ADHD) is characterized by inattention, hyperactivity, and impulsivity. A substantial proportion of individuals with ADHD also exhibit symptoms of Cognitive Disengagement Syndrome (CDS), which may further impair executive functions. Purpose This study aimed to examine the prevalence of comorbid ADHD and CDS (ADHD+) among adults in Bushehr, Iran, and to compare executive functioning between students with ADHD+ and healthy controls. Gender-based prevalence patterns were also explored. Methods A total of 690 university students were screened using the Barkley Adult ADHD Rating Scale-IV (BAARS-IV). ADHD and CDS diagnoses were confirmed via structured clinical interviews. From this sample, 43 adults with comorbid ADHD+CDS and 53 matched healthy controls completed three standardized executive function tasks: the Stroop Color-Word Test (SCWT), Wisconsin Card Sorting Test (WCST), and Tower of London Test (TOL). Results The prevalence of comorbid ADHD and CDS (ADHD+) was 25.15% across the total sample (N = 690), whereas 41.3% of those diagnosed with ADHD also met criteria for CDS; however MANOVA revealed significant group differences across ADHD symptom domains based on CDS comorbidity (Wilk’s λ = .48, F = 184.21, p < .001, η 2 = .52). Significant effects were observed for attentional problems (F = 103.12, p < .001, η 2 = .13), overall ADHD symptoms (F = 65.26, p < .001, η 2 = .09), and combined ADHD + scores (F = 259.43, p < .001, η 2 = .27). Smaller effects were found for hyperactivity and impulsivity (η 2 = .01). Conclusions Students with ADHD and comorbid CDS exhibit specific cognitive deficits, particularly in planning and attentional control, that should be considered in designing cognitive rehabilitation programs. These findings may inform culturally appropriate intervention strategies in Iran, such as cognitive rehabilitation programs targeting attentional control and planning deficits among university students with ADHD+CDS.