Executive Dysfunction in Restless Legs Syndrome: Clinical Correlates and Outcome After Therapeutic Management

Restless leg syndrome (RLS) is a common neurological disorder whose diagnosis is only clinical. The efficacy of dopaminergic agents in improvement of sensorimotor symptoms advance the hypothesis that altered dopaminergic transmission is at the origin of this condition. RLS usually leads to a sleep fragmentation, which induces sometimes severe insomnia most often associated, in clinical practice, to a cognitive complaint (attentional in nature). Executive functions in which dopaminergic transmission is heavily involved refer to a set of complex functions. At least three of them should be considered during their evaluation (ie flexibility, inhibition, and the updating of working memory). These functions are among the targets of the alteration of the quality and quantity of sleep. The few studies that have focused on the study of the integrity of executive functions in RLS have discordant results. The lack of control of key variables in the assessment of executive functioning (ie intellectual performance, depressive symptomatology, generalized slowing in information processing) and the lack of reference in the theoretical approach in executive functions are certainly the two main reasons. Moreover, the question of polysomnographic correlates and the reversibility of these cognitive abnormalities after pharmacological management of RLS remains unanswered today. The main objective of this study is to compare the executive performance of untreated RLS patients with a group of matched controls.