Prevalence of Restless Legs Syndrome in Adult ADHD and Its Subtypes

In this observational cross-sectional study, 49 subjects were assessed for sleep disorders and for ADHD symptoms. Thirty-six received an ADHD diagnosis (29: combined type (ADHD-C); 7: inattentive type). An RLS and RLS symptoms prevalence of 34.5% was found, with a higher prevalence rate in the ADHD-C subgroup, although not significantly (p = 0.066). RLS symptoms were correlated with particularly hyperactivity-impulsivity (ρ = 0.742; p: 0.000). ADHD patients with positive RLS scores reported higher scores on the ADHD-Rating scale compared with patients with negative RLS scores (Z: -2.968, p = 0.003), mainly due to higher hyperactivity-impulsivity scores (Z: -3.145; p = 0.002). Our findings show that clinicians need to be aware of RLS among adult ADHD patients, particularly those with severe hyperactivity-impulsivity symptoms.