Increased prevalence of nocturnal smoking in restless legs syndrome (RLS)

Objective: We investigated the prevalence of nocturnal smoking (NS) in patients with RLS. Methods: One hundred RLS patients living in Emilia-Romagna (Northern Italy) and 100 matched controls, randomly selected from the general population, underwent interviews for the presence of nocturnal smoking and for obsessive-compulsive traits, depression, excessive daytime sleepiness (EDS) and subjective sleep quality. Results: NS was more prevalent in RLS patients than controls (lifetime prevalence: 12% vs. 2%, P = 0.012). Patients with NS had more frequently Sleep-Related Eating Disorders (SRED) than patients without NS (83.3% vs. 26.1%, P = 0.0002). Pathological and borderline Maudsley Obsessive-Compulsive Inventory (MOCI) values as well as pathological values at the Beck Depression Inventory (BDI) increased from controls to RLS patients without NS to RLS patients with NS (P = 0.005 and P = 0.01, respectively). Conclusions: We demonstrate an increased prevalence of NS in patients with RLS, in many cases associated with increased SRED. NS may be associated with psychopathological traits in RLS and may be relevant in the management of RLS patients.