title: Association between sleep duration and mortality is mediated by markers of inflammation and health in older adults: the Health, Aging and Body Composition Study.
abstract: OBJECTIVE
  Inflammation may represent a common physiological pathway linking both short and long sleep duration to mortality. We evaluated inflammatory markers as mediators of the relationship between sleep duration and mortality in community-dwelling older adults.
  
  
  METHODS
  Prospective cohort with longitudinal follow-up for mortality outcomes.
  
  
  METHODS
  Pittsburgh, Pennsylvania, and Memphis, Tennessee.
  
  
  METHODS
  Participants in the Health, Aging and Body Composition (Health ABC) Study (mean age 73.6 ± 2.9 years at baseline) were sampled and recruited from Medicare listings.
  
  
  RESULTS
  Baseline measures of subjective sleep duration, markers of inflammation (serum interleukin-6, tumor necrosis factor-α, and C-reactive protein) and health status were evaluated as predictors of all-cause mortality (average follow-up = 8.2 ± 2.3 years). Sleep duration was related to mortality, and age-, sex-, and race-adjusted hazard ratios (HR) were highest for those with the shortest (< 6 h HR: 1.30, CI: 1.05-1.61) and longest (> 8 h HR: 1.49, CI: 1.15-1.93) sleep durations. Adjustment for inflammatory markers and health status attenuated the HR for short (< 6 h) sleepers (HR = 1.06, 95% CI = 0.83-1.34). Age-, sex-, and race-adjusted HRs for the > 8-h sleeper group were less strongly attenuated by adjustment for inflammatory markers than by other health factors associated with poor sleep with adjusted HR = 1.23, 95% CI = 0.93-1.63. Inflammatory markers remained significantly associated with mortality.
  
  
  CONCLUSIONS
  Inflammatory markers, lifestyle, and health status explained mortality risk associated with short sleep, while the mortality risk associated with long sleep was explained predominantly by lifestyle and health status.
authors.affiliation: Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, Pittsburgh, PA.
authors.forename: Martica H
authors.initials: MH
authors.lastname: Hall
authors.affiliation: Graduate School of Public Health, Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Smagula
authors.affiliation: Graduate School of Public Health, Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Boudreau
authors.affiliation: Departments of Epidemiology and Biostatistics, University of California at San Francisco, San Francisco, CA.
authors.forename: Hilsa N
authors.initials: HN
authors.lastname: Ayonayon
authors.affiliation: Graduate School of Public Health, Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Suzanne E
authors.initials: SE
authors.lastname: Goldman
authors.affiliation: Laboratory of Epidemiology, Demography and Biometry, Intramural Research Program, National Institute on Aging, Bethesda, MD.
authors.forename: Tamara B
authors.initials: TB
authors.lastname: Harris
authors.affiliation: Graduate School of Public Health, Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Barbara L
authors.initials: BL
authors.lastname: Naydeck
authors.affiliation: Departments of Epidemiology and Biostatistics, University of California at San Francisco, San Francisco, CA.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Rubin
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Laura
authors.initials: L
authors.lastname: Samuelsson
authors.affiliation: Department of Preventive Medicine, University of Tennessee, Memphis, TN.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Satterfield
authors.affiliation: San Francisco Coordinating Center, California Pacific Medical Center Research Institute, San Francisco, CA.
authors.forename: Katie L
authors.initials: KL
authors.lastname: Stone
authors.affiliation: Institute of Health Sciences, VU University Medical Center and EMGO Institute, VU Medical Center, Amsterdam, the Netherlands.
authors.forename: Marjolein
authors.initials: M
authors.lastname: Visser
authors.affiliation: Graduate School of Public Health, Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA.|Graduate School of Public Health, Department of Medicine, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Anne B
authors.initials: AB
authors.lastname: Newman
mesh_terms: D000368:Aged; D000375:Aging / Q000097:blood* / Q000502:physiology*; D015415:Biomarkers / Q000097:blood*; D001823:Body Composition; D002097:C-Reactive Protein / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006304:Health Status; D006801:Humans; D007249:Inflammation / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D008019:Life Style; D008137:Longitudinal Studies; D008297:Male; D009026:Mortality; D010414:Pennsylvania; D011446:Prospective Studies; D044469:Racial Groups; D012111:Residence Characteristics; D012890:Sleep / Q000502:physiology*; D007319:Sleep Initiation and Maintenance Disorders; D016019:Survival Analysis; D013714:Tennessee; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein
keywords: aging; epidemiology; inflammation; mortality; sleep