The effect of medical treatments on maladaptive daydreaming and mind-wandering in adult attention deficit hyperactivity disorder: a multicenter follow-up study

Background The effects of medical treatments on maladaptive daydreaming (MD) and mind-wandering (MW) in adult attention deficit hyperactivity disorder (ADHD) remain unclear. The aim of this study was to prospectively investigate the extent to which methylphenidate and atomoxetine are associated with changes in MD and MW. Methods The study included 85 drug-naive adults with ADHD and 53 healthy controls. Drug-naive ADHD patients were clinically followed for 12 weeks. The Adult ADHD Self-Report Scale (ASRS), Maladaptive Daydreaming Scale (MDS), and Mind-Wandering Questionnaire (MWQ) were administered at baseline and at 4-, 8-, and 12-week follow-ups. Results MDS and MWQ scores were significantly higher in patients with ADHD than in healthy controls. During the 12-week follow-up, significant reductions in ASRS, MDS and MWQ scores were observed ( p < 0.001). The largest reductions were observed in the first 4 weeks. MDS scores continued to decrease through week 12, whereas MWQ scores remained similar between weeks 8 and 12. There was no significant difference between methylphenidate and atomoxetine in terms of changes over time (ASRS: F = 1.606, p = 0.209; MDS: F = 0.886, p = 0.384; MWQ: F = 1.759, p = 0.182). Higher baseline MDS scores were associated with greater reductions in MDS and MWQ scores. The association with MDS reduction remained significant after adjustment for baseline MWQ (F = 27.942, p < 0.001, ηp² = 0.171), and the association with MWQ reduction remained significant after adjustment for baseline ASRS (F = 10.135, p < 0.001, ηp² = 0.070). Although baseline MDS was associated with greater ASRS reduction in the unadjusted analysis, this association was no longer significant after adjustment for baseline MWQ (F = 2.341, p = 0.109, ηp² = 0.017), whereas baseline MWQ remained significantly associated with ASRS reduction (F = 14.224, p < 0.001, ηp² = 0.095). Conclusion In ADHD, both stimulant and non-stimulant medications were associated with significant reductions in MD and MW. These reductions were most evident during the first 4 weeks. MDS scores continued to decrease through week 12, whereas MWQ scores remained similar between weeks 8 and 12. Higher baseline MD severity was associated with greater reductions in MD and MW but did not independently account for the reduction in ADHD symptoms after baseline MW was considered. These findings suggest that MD and MW are related but distinguishable dimensions and that MW may be more closely associated with changes in core ADHD symptoms. Given the non-randomized design and potential confounding, between-group comparisons should be interpreted cautiously.