title: Daytime sleepiness predicts mortality and cardiovascular disease in older adults. The Cardiovascular Health Study Research Group.
abstract: BACKGROUND
  As part of the baseline examination in the Cardiovascular Health Study, sleep disturbance symptoms including snoring and daytime sleepiness, were assessed as potential risk factors or precipitants of cardiovascular disease (CVD). Because of the association of sleep disturbance with poorer health and the possible associations of sleep apnea with CVD, we hypothesized that those with poorer sleep or daytime sleepiness may be at increased risk of mortality or incident CVD.
  
  
  METHODS
  Participants (n = 5888) were recruited in 1989, with an additional minority cohort recruited in 1993, in four US communities for a cohort study designed to evaluate risk factors for cardiovascular disease.
  
  
  METHODS
  An interview-administered questionnaire regarding health and sleep habits with ongoing ascertainment of total mortality and cardiovascular disease morbidity and mortality, including total CVD morbidity and mortality, incident myocardial infarction, and congestive heart failure.
  
  
  RESULTS
  Daytime sleepiness was the only sleep symptom that was significantly associated with mortality in both men and women. The unadjusted hazard ratio was 2.12 (1.66, 2.72) in women and 1.40 (1.12, 1.73) in men. Men who reported difficulty falling asleep also had an increased mortality rate (HR = 1.43 (1.14, 1.80)) which was not seen in women. The risks were attenuated with adjustment for age but remained significant for daytime sleepiness in women (HR = 1.82 (1.42, 2.34)) and for difficulty falling asleep in men. (HR = 1.29 (1.03, 1.63)). Frequent awakenings, early morning awakening, and snoring were not associated with a significantly increased risk of mortality in these older men and women. Crude event rates were evaluated for total incident cardiovascular morbidity and mortality, incident myocardial infarction, and incident congestive heart failure (CHF). Incident CVD rates were higher in both men and women with daytime sleepiness. The aged adjusted HR was 1.35 (95% CI = 1.03, 1.76) in men and was 1.66 (95% CI = 1.28, 2.16) in women. Incident CVD was not higher in those with any other sleep disturbance including snoring. The risk of CVD events associated with daytime sleepiness was attenuated but remained significant in women after adjustment for age. Incident myocardial infarction (MI) rates were also higher in women with daytime sleepiness but were not significantly higher in men. Incident CHF rates were increased in both men and women with daytime sleepiness. In men, the age adjusted HR was 1.49 (95% CI, 1.12- 1.98) and in women, was 2.21 (95% CI, 1.64-2.98). Women reporting both daytime sleepiness and frequent awakening had a hazard ratio of 2.34 (95% CI, 1.66-3.29) for incident CHF compared with those with daytime sleepiness but without frequent awakening. This interaction was not found in men.
  
  
  CONCLUSIONS
  In this study, daytime sleepiness was the only sleep disturbance symptom that was associated with mortality, incident CVD morbidity and mortality, MI, and CHF. These findings were stronger in women than men, i.e., the associations persisted for mortality, CVD, and CHF in women after adjustment for age and other factors. Thus, a report of daytime sleepiness identifies older adults at increased risk for total and cardiovascular mortality, and is an independent risk factor in women.
authors.affiliation: University of Pittsburgh, Pennsylvania 15213, USA.
authors.forename: A B
authors.initials: AB
authors.lastname: Newman
authors.forename: C F
authors.initials: CF
authors.lastname: Spiekerman
authors.forename: P
authors.initials: P
authors.lastname: Enright
authors.forename: D
authors.initials: D
authors.lastname: Lefkowitz
authors.forename: T
authors.initials: T
authors.lastname: Manolio
authors.forename: C F
authors.initials: CF
authors.lastname: Reynolds
authors.forename: J
authors.initials: J
authors.lastname: Robbins
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000401:mortality; D015331:Cohort Studies; D005260:Female; D006304:Health Status; D006333:Heart Failure / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000453:epidemiology; D016017:Odds Ratio; D012307:Risk Factors; D012737:Sex Factors; D012891:Sleep Apnea Syndromes / Q000453:epidemiology; D012894:Sleep Stages / Q000502:physiology; D012893:Sleep Wake Disorders / Q000453:epidemiology*; D012913:Snoring / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology