title: Associations between sleep architecture and sleep-disordered breathing and cognition in older community-dwelling men: the Osteoporotic Fractures in Men Sleep Study.
abstract: OBJECTIVE
  To examine the association between sleep architecture, sleep-disordered breathing, and cognition in older men.
  
  
  METHODS
  Population-based cross-sectional study.
  
  
  METHODS
  Six clinical sites in the United States.
  
  
  METHODS
  Two thousand nine hundred nine community-dwelling men aged 67 and older who were not selected on the basis of sleep problems or cognitive impairment.
  
  
  METHODS
  Predictors were measured using in-home polysomnography: sleep architecture, nocturnal hypoxemia (any sleep time with arterial oxygen saturation <80%), apnea-hypopnea index (AHI), and arousal index. Cognitive outcomes were measured using the modified Mini-Mental State Examination (3MS), Trail-Making Test Part B (TMT-B), and the Digit Vigilance Test (DVT).
  
  
  RESULTS
  Analyses adjusted for age, race, education, body mass index, lifestyle, comorbidities, and medication use showed that participants who spent less percentage of time in rapid eye movement (REM) sleep had lower levels of cognition; participants in the lowest quartile (<14.8%) took an average of 5.9 seconds longer on the TMT-B and 20.1 seconds longer on the DVT than those in the highest quartile (≥23.7%). Similarly, greater percentage of time spent in Stage 1 sleep was related to poorer cognitive function. Participants in the highest quartile of Stage 1 sleep (≥8.6%) had worse cognitive scores on average than those in the lowest quartile (<4.0%). Those with nocturnal hypoxemia took an average of 22.3 seconds longer to complete the DVT than those without, but no associations were found with 3MS or the TMT-B.
  
  
  CONCLUSIONS
  Spending less percentage of time in REM sleep and greater percentage of time in Stage 1 sleep and having higher levels of nocturnal hypoxemia were associated with poorer cognition in older men. Further studies are needed to clarify the direction of these associations and to explore potential mechanisms.
authors.affiliation: Research Institute, California Pacific Medical Center, San Francisco, California, USA. tblackwell@sfcc-cpmc.net
authors.forename: Terri
authors.initials: T
authors.lastname: Blackwell
authors.forename: Kristine
authors.initials: K
authors.lastname: Yaffe
authors.forename: Sonia
authors.initials: S
authors.lastname: Ancoli-Israel
authors.forename: Susan
authors.initials: S
authors.lastname: Redline
authors.forename: Kristine E
authors.initials: KE
authors.lastname: Ensrud
authors.forename: Marcia L
authors.initials: ML
authors.lastname: Stefanick
authors.forename: Alison
authors.initials: A
authors.lastname: Laffan
authors.forename: Katie L
authors.initials: KL
authors.lastname: Stone
mesh_terms: D000368:Aged; D003072:Cognition Disorders / Q000209:etiology*; D003430:Cross-Sectional Studies; D006801:Humans; D000860:Hypoxia / Q000150:complications; D008297:Male; D058866:Osteoporotic Fractures / Q000150:complications; D012111:Residence Characteristics; D012890:Sleep / Q000502:physiology*; D012891:Sleep Apnea Syndromes / Q000150:complications*