Background: Restless legs syndrome (RLS), a common sensorimotor disorder, has a wide range of severity from merely annoying to affecting sleep and quality of life severely enough to warrant medical treatment. Previous epidemiological studies, however, have failed to determine the prevalence of those with clinically significant RLS symptoms and to examine the life effects and medical experiences of this group.
Methods: A total of 16 202 adults (aged >/=18 years) were interviewed using validated diagnostic questions to determine the presence, frequency, and severity of RLS symptoms; respondents reporting RLS symptoms were asked about medical diagnoses and the impact of the disorder and completed the Short Form-36 Health Survey (SF-36). Criteria determined by RLS experts for medically significant RLS (frequency at least twice a week, distress at least moderate) defined "RLS sufferers" as a group most likely to warrant medical treatment.
Results: In all, 15 391 fully completed questionnaires were obtained; in the past year, RLS symptoms of any frequency were reported by 1114 (7.2%). Symptoms occurred at least weekly for 773 respondents (5.0%); they occurred at least 2 times per week and were reported as moderately or severely distressing by 416 (2.7%). Of those 416 (termed RLS sufferers), 337 (81.0%) reported discussing their symptoms with a primary care physician, and only 21 (6.2%) were given a diagnosis of RLS. The SF-36 scores for RLS sufferers were significantly below population norms, matching those of patients with other chronic medical conditions.
Conclusion: Clinically significant RLS is common (prevalence, 2.7%), is underdiagnosed, and significantly affects sleep and quality of life.