title: Ten-year natural course of habitual snoring and restless legs syndrome in a population aged 61-63 years at the baseline.
abstract: OBJECTIVE
  We investigated the prevalence, natural course, and associated risk factors of habitual snoring (HS) and restless legs syndrome (RLS) over a period of 10 years among an aging population from their early sixties to their seventies.
  
  
  METHODS
  A population-based follow-up study among all persons born in 1935 and living in the city of Oulu in northern Finland was conducted. In this study, we examined subjects who had participated in two subsequent surveys conducted in 1996-1998 and 2007-2008. The data were gathered by questionnaires, as well as by laboratory and clinical measurements.
  
  
  RESULTS
  Altogether 457 (55%) of the 838 eligible subjects participated in both surveys. The prevalence of both RLS and HS decreased during the 10 years from 21% to 15% and from 26% to 19%, respectively. Half of those who snored in 1996-1998 stopped snoring in 10 years time, and half of those who suffered from restless legs at least three times per week in 1996-1998 suffered from this syndrome never or less than once a week in 2007-2008. The 10-year incidence of new cases of both HS and RLS was 7%. Male gender predicted best the incidence of new HS in 10 years, while the Zung sum score as a marker of depressive symptoms and waist circumference predicted RLS.
  
  
  CONCLUSIONS
  Overall, the prevalence of both HS and RLS seems to diminish during aging. The causes behind this still remain unknown and should be investigated with more sophisticated methods.
authors: Institute of Health Sciences, University of Oulu, Oulu, Finland. anna-kaisa.juuti@oulu.fi
authors: Anna-Kaisa
authors: AK
authors: Juuti
authors: Liisa
authors: L
authors: Hiltunen
authors: Ulla
authors: U
authors: Rajala
authors: Mauri
authors: M
authors: Laakso
authors: Pirjo
authors: P
authors: Härkönen
authors: Sirkka
authors: S
authors: Keinänen-Kiukaanniemi
authors: Esa
authors: E
authors: Läärä
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D005387:Finland; D006306:Health Surveys; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012148:Restless Legs Syndrome / Q000175:diagnosis* / Q000453:epidemiology*; D012737:Sex Factors; D012913:Snoring / Q000175:diagnosis* / Q000453:epidemiology*; D055105:Waist Circumference