title: Association between obstructive sleep apnea and cancer incidence in a large multicenter Spanish cohort.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) has been associated with increased cancer mortality, but whether it is also associated with cancer incidence is unknown.
  
  
  OBJECTIVE
  To investigate whether OSA is associated with increased cancer incidence in a large clinical cohort.
  
  
  METHODS
  A multicenter, clinical cohort study including consecutive patients investigated for suspected OSA between 2003 and 2007 in seven Spanish teaching hospitals. Apnea-hypopnea index (AHI) and percent nighttime with oxygen saturation less than 90% (TSat(90)) were used as surrogates of OSA severity, both as continuous variables and categorized by tertiles. Cox proportional hazards regression analyses were used to calculate hazard ratio (HR) and 95% confidence interval (CI) for cancer incidence after adjusting for confounding variables.
  
  
  RESULTS
  A total of 4,910 patients were analyzed (median follow-up, 4.5 yr; interquartile range, 3.4-5.2). Compared with the lower TSat(90) category (<1.2%), the adjusted hazards (95% CI) of cancer incidence for increasing categories were 1.58 (1.07-2.34) for TSat(90) 1.2-12% and 2.33 (1.57-3.46) for TSat(90) greater than 12%. Continuous TSat(90) was also associated with cancer incidence (adjusted HR, 1.07 [1.02-1.13] per 10-unit increase in TSat(90)). In stratified analyses, TSat(90) was associated with cancer incidence in patients younger than 65 years (adjusted HR, 1.13 [95% CI, 1.06-1.21] per 10-unit increase in TSat(90)) and males (adjusted HR, 1.11 [95% CI, 1.04-1.17] per 10-unit increase in TSat(90)). AHI was not associated with cancer incidence in the adjusted analyses, except for patients younger than 65 years (adjusted HR for AHI >43 vs. <18.7, 1.66; 95% CI, 1.04-2.64).
  
  
  CONCLUSIONS
  Increased overnight hypoxia as a surrogate of OSA severity was associated with increased cancer incidence. This association seems to be limited to men and patients younger than 65 years of age.
authors.affiliation: Respiratory Department, Hospital Universitario de Valme, Sevilla, Spain. fracamrod@gmail.com
authors.forename: Francisco
authors.initials: F
authors.lastname: Campos-Rodriguez
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Martinez-Garcia
authors.forename: Montserrat
authors.initials: M
authors.lastname: Martinez
authors.forename: Joaquin
authors.initials: J
authors.lastname: Duran-Cantolla
authors.forename: Monica de la
authors.initials: Mde L
authors.lastname: Peña
authors.forename: María J
authors.initials: MJ
authors.lastname: Masdeu
authors.forename: Monica
authors.initials: M
authors.lastname: Gonzalez
authors.forename: Felix del
authors.initials: Fd
authors.lastname: Campo
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Gallego
authors.forename: Jose M
authors.initials: JM
authors.lastname: Marin
authors.forename: Ferran
authors.initials: F
authors.lastname: Barbe
authors.forename: Jose M
authors.initials: JM
authors.lastname: Montserrat
authors.forename: Ramon
authors.initials: R
authors.lastname: Farre
mesh_terms: D000367:Age Factors; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology*; D012189:Retrospective Studies; D012737:Sex Factors; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology*; D013030:Spain / Q000453:epidemiology