Prevalence of Restless Legs Syndrome in Migraine Patients: A Case-Control Study. Analysis of Risk Factors for Restless Legs Syndrome in Migraine Patients

Background: Restless legs syndrome (RLS) is a sensorimotor disorder. It can be idiopathic, associated to other diseases or to pharmacologic treatments. RLS has been reported to occur more frequently in migraine patients, but a clear pathogenetic link seems still under debate. We aimed to evaluate RLS prevalence in migraine, impact on sleep quality and the main clinical determinants of this association. Methods: Migraine patients and age- and sex-matched controls were enrolled from 1st January 2011 to 30th December 2012. Migraine and RLS diagnosis complied with already published clinical criteria. Medical and pharmacological histories, as well as structured questionnaires were collected. Results: RLS was found in 29/180 (16.1%) patients and 11/180 (6.1%) controls. The odds ratio (OR) for RLS was 2.95 (CI 95%, 1.42-6.11). Among migraine patients, after adjustment for possible confounding factors, familial history (OR 3.863, CI 1.076-13.873), and serotoninergic overload (OR 3.654, CI 1.347-9.916) were significantly associated with RLS occurrence. Pittsburgh Sleep Quality Index score was higher in migraine patients with RLS than in subjects without RLS. Conclusions: The confirmed association between migraine and RLS might be because of familial predisposition and to serotoninergic drugs effect, possibly interfering with the balance between dopaminergic and serotoninergic pathways.