Mind-wandering, emotion dysregulation, and non-suicidal self-injury in adult attention-deficit/hyperactivity disorder: a comparative study with remitted major depressive disorder

Abstract Background Although a link between Attention-Deficit/Hyperactivity Disorder (ADHD) and Non-Suicidal Self-Injury (NSSI) has been established, the roles of excessive mind-wandering and emotion dysregulation in this association remain insufficiently understood. This study aimed to evaluate levels of NSSI, emotional dysregulation, and excessive mind-wandering in adults diagnosed with ADHD, comparing them to a control group of individuals with Major Depressive Disorder in remission (rMDD). Methods A total of 93 participants with no comorbidities—confirmed as ADHD ( n = 48) or rMDD ( n = 45) via the Structured Clinical Interview for DSM-5—were included. Participants completed the Adult ADD/ADHD Scale, The Inventory of Statements about Self-Injury (ISAS), the Difficulties in Emotion Regulation Scale (DERS), and the Mind Excessively Wandering Scale (MEWS). Data were analyzed using intergroup comparisons and logistic regression analysis. Results Lifetime prevalence of NSSI ( p = 0.380) and DERS scores ( p = 0.528) were similar across both groups. However, MEWS scores were significantly higher in the ADHD group ( p = 0.008) and positively correlated with ADHD symptom severity ( p < 0.05). Additionally, a positive correlation was observed between MEWS and total DERS scores within the ADHD group ( p < 0.05). Furthermore, ISAS scores were positively correlated with DERS ( r = 0.55, p = 0.03), but not with ADHD symptomseverity or MEWS. Regarding clinical history, childhood home accidents ( p = 0.013), graderetention ( p < 0.001), and disciplinary actions ( p = 0.002), along with adult traffic violations ( p = 0.010), were significantly more frequent in the ADHD group. In an exploratory multivariable logistic regression analysis, adjusted for collinearity, revealed that none of the evaluated clinical dimensions, including age, MEWS, and DERS scores, significantly differentiated between the two diagnostic groups (all p > 0.05). Conclusions This study demonstrates no significant difference in lifetime NSSI or emotional dysregulation between adult ADHD and rMDD groups. Although mind-wandering levels were higher in the ADHD group, this variable did not significantly differentiate between the diagnoses. The findings suggest that self-harm behaviors in ADHD may be more closely associated with emotional dysregulation than with mind-wandering.