title: Obstructive sleep apnea is associated with increased high-sensitivity cardiac troponin T levels.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) is associated with increased cardiovascular risk. Stress imposed on the myocardium by repeated severe hypoxemia and/or BP surges during sleep may result in subclinical myocardial injury. A high-sensitivity cardiac troponin T (hs-cTnT) assay has been developed. We hypothesized that the severity of OSA, as assessed by the apnea-hypopnea index (AHI), is associated with circulating levels of hs-cTnT in the general population.
  
  
  METHODS
  Five hundred five subjects drawn from the general population (age range, 30-65 years; 45% women) underwent in-hospital polysomnography and had morning blood samples drawn. Oversampling of subjects at high risk of OSA was performed.
  
  
  RESULTS
  Overall, hs-cTnT was detectable (≥ 3 ng/L) in 216 subjects (42.8%). After categorizing subjects according to AHI cutoffs that correspond to no, mild to moderate, and severe OSA, the proportion of subjects with detectable hs-cTnT levels increased with increasing severity of OSA (P for trend < .001). Multivariate logistic regression with detectable hs-cTnT as the dependent variable was used to further assess the association between OSA and troponin T. After adjustment for significant univariate predictors of detectable hs-cTnT, the association between AHI and hs-cTnT was no longer statistically significant.
  
  
  CONCLUSIONS
  The prevalence of detectable hs-cTnT increases in proportion to OSA severity, but this association is likely to be caused by a clustering of cardiovascular risk factors among subjects with OSA.
authors.affiliation: Division of Medicine, Akershus University Hospital, Lørenskog, Oslo, Norway; K.G. Jebsen Cardiac Research Centre, Center for Heart Failure Research and Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Anna
authors.initials: A
authors.lastname: Randby
authors.affiliation: Division of Medicine, Akershus University Hospital, Lørenskog, Oslo, Norway; K.G. Jebsen Cardiac Research Centre, Center for Heart Failure Research and Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Silje K
authors.initials: SK
authors.lastname: Namtvedt
authors.affiliation: Division of Medicine, Akershus University Hospital, Lørenskog, Oslo, Norway; K.G. Jebsen Cardiac Research Centre, Center for Heart Failure Research and Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Gunnar
authors.initials: G
authors.lastname: Einvik
authors.affiliation: Department of Otorhinopharyngology, Akershus University Hospital, Lørenskog, Oslo, Norway; Department of Behavioral Sciences in Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
authors.forename: Harald
authors.initials: H
authors.lastname: Hrubos-Strøm
authors.affiliation: Division of Diagnostics and Technology, Akershus University Hospital, Lørenskog, Oslo, Norway.
authors.forename: Tor-Arne
authors.initials: TA
authors.lastname: Hagve
authors.affiliation: Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic and Foundation, Rochester, MN.
authors.forename: Virend K
authors.initials: VK
authors.lastname: Somers
authors.affiliation: Division of Medicine, Akershus University Hospital, Lørenskog, Oslo, Norway; K.G. Jebsen Cardiac Research Centre, Center for Heart Failure Research and Institute of Clinical Medicine, University of Oslo, Oslo, Norway. Electronic address: torbjorn.omland@medisin.uio.no.
authors.forename: Torbjørn
authors.initials: T
authors.lastname: Omland
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009206:Myocardium / Q000378:metabolism*; D017286:Polysomnography; D015995:Prevalence; D012307:Risk Factors; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000453:epidemiology* / Q000503:physiopathology; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D020107:Troponin T