title: Migraine and restless legs syndrome: a systematic review.
abstract: BACKGROUND
  Restless legs syndrome (RLS) is increasingly being reported as a comorbidity of migraine.
  
  
  METHODS
  We conducted a systematic review and meta-analysis of studies investigating RLS in headache/migraine and vice versa. We calculated the prevalence and 95% confidence intervals (CI) of RLS in headache/migraine, of headache/migraine in RLS and controls, and odds ratios (ORs) of the association between the conditions. We then determined pooled effect estimates for the associations.
  
  
  RESULTS
  We identified 24 studies. RLS prevalence in migraine ranged from 8.7% to 39.0% with no apparent differences based on gender and aura status. Prevalence among controls was compatible with the literature. Migraine prevalence in RLS ranged from 15.1% to 62.6%. We did not pool prevalence data because of high unexplained heterogeneity. High heterogeneity with respect to the association between any migraine and RLS could be explained by study design. Pooled analyses showed substantially higher effect estimates in case-control studies (pooled OR = 4.19, 95% CI 3.07-5.71; I (2) = 0.0%) than in cohort studies (pooled OR = 1.22, 95% CI 1.14-1.30; I (2) = 0.0%).
  
  
  CONCLUSIONS
  Our results support the concept of RLS as an important comorbidity of migraine. However, the degree of association appears to be strongly determined by study design. Potential effects by gender and aura status and the role of RLS in other headache disorders remain unclear.
authors.affiliation: Department of Neurology, University Hospital Essen, Germany markus.schuerks@uni-due.de tobias.kurth@u-bordeaux.fr.
authors.forename: Markus
authors.initials: M
authors.lastname: Schürks
authors.affiliation: Division of Public Health Sciences, Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Anke
authors.initials: A
authors.lastname: Winter
authors.affiliation: Institute of Epidemiology and Social Medicine, University of Münster, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Berger
authors.affiliation: Division of Preventive Medicine, Department of Medicine; Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA College of Health Sciences, University of Bordeaux, France Inserm Research Center for Epidemiology and Biostatistics - Team Neuroepidemiology, Bordeaux, France.
authors.forename: Tobias
authors.initials: T
authors.lastname: Kurth
mesh_terms: D016022:Case-Control Studies; D008881:Migraine Disorders / Q000150:complications / Q000453:epidemiology*; D015995:Prevalence; D012148:Restless Legs Syndrome / Q000453:epidemiology* / Q000209:etiology
keywords: Migraine; association; meta-analysis; prevalence; restless legs syndrome; systematic review