title: Prospective study of restless legs syndrome and mortality among men.
abstract: OBJECTIVE
  To prospectively examine whether men with restless legs syndrome (RLS) had an increased risk of mortality.
  
  
  METHODS
  This was a prospective cohort study of 18,425 US men free of diabetes, arthritis, and renal failure in the Health Professionals Follow-up Study (HPFS). In 2002, RLS was assessed using a set of standardized questions. Deaths were identified from state vital statistics records, the National Death Index, family reports, and the postal system.
  
  
  RESULTS
  During 8 years of follow-up (2002-2010), we documented 2,765 deaths. In an age-adjusted model, RLS was associated with a 39% increased risk of mortality (hazard ratio [HR] = 1.39; 95% confidence interval [CI] 1.19-1.62; p < 0.0001). The association between RLS and mortality was slightly attenuated after further adjustment for body mass index, lifestyle factors, chronic conditions, sleep duration, and other sleep-related disorders (adjusted HR = 1.30; 95% CI 1.11-1.52; p = 0.003). When we further excluded those with major chronic conditions (e.g., cancer, high blood pressure, cardiovascular disease, and other comorbidities), the adjusted HR was 1.92 (95% CI 1.03-3.56; p = 0.04). The interactions between RLS and other risk factors (older age, overweight, short sleep duration, smoking, low physical activity, and unhealthy diet) in relation to total mortality risk were not significant (p for interaction >0.2 for all).
  
  
  CONCLUSIONS
  We observed that men with RLS had a higher overall mortality and this association was independent of known risk factors. The increased mortality in RLS was more frequently associated with respiratory disease, endocrine disease, nutritional/metabolic disease, and immunologic disorders. Future research exploring the pathophysiologic relationship between these disorders and RLS is warranted.
authors.affiliation: Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA. yanping.li@channing.harvard.edu
authors.forename: Yanping
authors.initials: Y
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: John W
authors.initials: JW
authors.lastname: Winkelman
authors.forename: Atul
authors.initials: A
authors.lastname: Malhotra
authors.forename: Jing
authors.initials: J
authors.lastname: Ma
authors.forename: Xiang
authors.initials: X
authors.lastname: Gao
mesh_terms: D015992:Body Mass Index; D015331:Cohort Studies; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008019:Life Style; D008297:Male; D011446:Prospective Studies; D012148:Restless Legs Syndrome / Q000150:complications / Q000401:mortality*; D012307:Risk Factors; D011795:Surveys and Questionnaires