title: Increased risk of heart failure in women with symptoms of sleep-disordered breathing.
abstract: BACKGROUND
  An association between obstructive sleep apnea and the incidence of heart failure has been reported in men but not in women. The aim of this study was to investigate whether a combination of snoring and excessive daytime sleepiness, the two main symptoms of obstructive sleep apnea syndrome, was able to predict incident heart failure in a population-based sample of women.
  
  
  METHODS
  The population-based cohort study Sleep and Health in Women (SHE; n = 5990 women born between 1901 and 1980) was used, with baseline questionnaire data from April 2000 relating to snoring, excessive daytime sleepiness, and covariates. Using data retrieved from the Swedish National Patient Register and Cause of Death Register, the follow-up of incident heart failure continued until 31 December 2011.
  
  
  RESULTS
  Among women with both snoring and excessive daytime sleepiness at baseline, 5.3% developed heart failure during follow-up compared with 0.9% in the reference group with neither snoring nor excessive daytime sleepiness. After adjustment for age, waist circumference, smoking, alcohol, hypertension, diabetes, previous myocardial infarction, physical inactivity, depressive symptoms, menopausal status, and hormone replacement therapy, women with the combination of snoring and excessive daytime sleepiness had a twofold increase in the risk of incident heart failure (hazard ratio [HR] 2.2 95% confidence interval [CI] 1.1-4.4).
  
  
  CONCLUSIONS
  Symptoms of obstructive sleep apnea, that is, the combination of snoring and excessive daytime sleepiness, are associated with an increased risk of developing heart failure in women.
authors: Department of Medical Sciences, Respiratory, Allergy, and Sleep Research, Uppsala University, Uppsala, Sweden. Electronic address: mirjam.ljunggren@medsci.uu.se.
authors: Mirjam
authors: M
authors: Ljunggren
authors: Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors: Liisa
authors: L
authors: Byberg
authors: Department of Medical Sciences, Respiratory, Allergy, and Sleep Research, Uppsala University, Uppsala, Sweden.
authors: Jenny
authors: J
authors: Theorell-Haglöw
authors: Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden; Department of Medical Sciences, Cardiology, Uppsala University, Uppsala, Sweden.
authors: Bertil
authors: B
authors: Lindahl
authors: Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors: Karl
authors: K
authors: Michaëlsson
authors: Department of Medical Sciences, Respiratory, Allergy, and Sleep Research, Uppsala University, Uppsala, Sweden.
authors: Eva
authors: E
authors: Lindberg
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D006970:Disorders of Excessive Somnolence / Q000150:complications; D005260:Female; D006333:Heart Failure / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D017286:Polysomnography; D012307:Risk Factors; D012891:Sleep Apnea Syndromes / Q000150:complications*; D012913:Snoring / Q000150:complications; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology
keywords: Excessive daytime sleepiness; Heart failure; Obstructive sleep apnea syndrome; Snoring; Women