title: Impact of age on pH, 8-isoprostane, and nitrogen oxides in exhaled breath condensate.
abstract: BACKGROUND
  Few studies have addressed the effects of aging on levels of inflammatory markers in exhaled breath condensate (EBC). The aim of this study was to determine whether there are significant age-associated differences in pH, 8-isoprostane, and nitrogen oxide values in EBC from a population of healthy adults.
  
  
  METHODS
  EBC samples were obtained from 75 healthy volunteers aged 18 to 80 years and stratified into five groups according to age (n = 15): 18 to 29, 30 to 39 years, 40 to 49 years, 50 to 59 years, and 60 to 80 years. The following were measured in the samples collected: pH before and after deaeration, nitrite, nitrate, and 8-isoprostane. Differences between the groups were assessed by the Kruskal-Wallis test.
  
  
  RESULTS
  Significant differences in deaerated pH (p < 0.0001) were found in the group of individuals 60 to 80 years of age as compared to the remaining groups. Significant differences were also found in 8-isoprostane levels between the younger and older groups (18 to 29 years and 30 to 39 years of age; p = 0.006 and p = 0.034, respectively). There were no significant differences in nitrite or nitrate values between younger and older individuals.
  
  
  CONCLUSIONS
  The results of this study indicate that pH and 8-isoprostane levels in EBC show a relationship with age. Thus, values obtained in studies with control groups may require adjustment for these factors.
authors.affiliation: Ciber Enfermedades Respiratorias, Fisiologia, Immunologia, Universidad Autònoma de Barcelona, Barcelona, Spain. Electronic address: mjcruz@ir.vhebron.net.
authors.forename: María-Jesus
authors.initials: MJ
authors.lastname: Cruz
authors.affiliation: Servei de Pneumologia Hospital Vall d'Hebron, Fisiologia, Immunologia, Universidad Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Sánchez-Vidaurre
authors.affiliation: Universidad Autònoma de Barcelona; Servei de Pneumologia, Fisiologia, Immunologia, Universidad Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Pablo-Vicente
authors.initials: PV
authors.lastname: Romero
authors.affiliation: Servei de Pneumologia Hospital Vall d'Hebron, Fisiologia, Immunologia, Universidad Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Ferran
authors.initials: F
authors.lastname: Morell
authors.affiliation: Hospital de Bellvitge; and Departament de Biologia Cellular, Fisiologia, Immunologia, Universidad Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Muñoz
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000378:metabolism; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D012016:Reference Values; D012119:Respiration; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D015415:Biomarkers; C075750:8-epi-prostaglandin F2alpha; D009569:Nitric Oxide; D015237:Dinoprost