ADHD in aging

BACKGROUND. Attention-Deficit/Hyperactivity Disorder (ADHD) is a highly prevalent neurodevelopmental condition, which may be associated with life-enduring cognitive dysfunction. It has been hypothesized that age-related cognitive decline may overlap with preexisting deficits in older ADHD patients, leading to increased problems to manage everyday-life activities. This phenomenon may mimic neurodegenerative disorders, in particular Mild Cognitive Impairment (MCI). This cross-sectional study aims to assess cognitive and behavioral differences between older subjects with ADHD and MCI. METHODS. A total of 107 older participants (41 controls; 40 MCI and 26 ADHD; mean age = 67.60 ± 7.50 years; mean schooling = 15.14 ± 2.77 years; 65.4% females) underwent clinical, cognitive, and behavioral assessments by a multidisciplinary team at the Memory Clinic, D’Or Institute for Research and Education, Rio de Janeiro, Brazil. Mean scores in neuropsychological tasks and behavioral scales were compared across groups. RESULTS. Participants with ADHD showed poorer performances than controls in episodic memory, executive function, and attention tests. Scores were comparable between MCI and ADHD for all domains, except for the memory tasks: MCI subjects presented worse results in encoding and delayed-recall subtests, whereas ADHD were more impaired in recognition test. DISCUSSION. MCI and ADHD in older individuals are dissociated clinical entities with overlapping, but distinct, cognitive profiles. Assessment of verbal memory, especially using recognition tasks, but not evaluation of executive function, could allow differentiation between these disorders.