title: Indoor particles affect vascular function in the aged: an air filtration-based intervention study.
abstract: BACKGROUND
  Exposure to particulate matter is associated with risk of cardiovascular events, possibly through endothelial dysfunction, and indoor air may be most important.
  
  
  OBJECTIVE
  We investigated effects of controlled exposure to indoor air particles on microvascular function (MVF) as the primary endpoint and biomarkers of inflammation and oxidative stress as secondary endpoints in a healthy elderly population.
  
  
  METHODS
  A total of 21 nonsmoking couples participated in a randomized, double-blind, crossover study with two consecutive 48-hour exposures to either particle-filtered or nonfiltered air (2,533-4,058 and 7,718-12,988 particles/cm(3), respectively) in their homes.
  
  
  RESULTS
  MVF was assessed noninvasively by measuring digital peripheral artery tone after arm ischemia. Secondary endpoints included hemoglobin, red blood cells, platelet count, coagulation factors, P-selectin, plasma amyloid A, C-reactive protein, fibrinogen, IL-6, tumor necrosis factor-alpha, protein oxidation measured as 2-aminoadipic semialdehyde in plasma, urinary 8-iso-prostaglandin F(2alpha), and blood pressure. Indoor air filtration significantly improved MVF by 8.1% (95% confidence interval, 0.4-16.3%), and the particulate matter (diameter < 2.5 mum) mass of the indoor particles was more important than the total number concentration (10-700 nm) for these effects. MVF was significantly associated with personal exposure to iron, potassium, copper, zinc, arsenic, and lead in the fine fraction. After Bonferroni correction, none of the secondary biomarkers changed significantly.
  
  
  CONCLUSIONS
  Reduction of particle exposure by filtration of recirculated indoor air for only 48 hours improved MVF in healthy elderly citizens, suggesting that this may be a feasible way of reducing the risk of cardiovascular disease.
authors.affiliation: D. Institute of Public Health, Department of Environmental and Occupational Health, Øster Farimagsgade 5A, DK-1014 Copenhagen K, Denmark.
authors.forename: Elvira Vaclavik
authors.initials: EV
authors.lastname: Bräuner
authors.forename: Lykke
authors.initials: L
authors.lastname: Forchhammer
authors.forename: Peter
authors.initials: P
authors.lastname: Møller
authors.forename: Lars
authors.initials: L
authors.lastname: Barregard
authors.forename: Lars
authors.initials: L
authors.lastname: Gunnarsen
authors.forename: Alireza
authors.initials: A
authors.lastname: Afshari
authors.forename: Peter
authors.initials: P
authors.lastname: Wåhlin
authors.forename: Marianne
authors.initials: M
authors.lastname: Glasius
authors.forename: Lars Ove
authors.initials: LO
authors.lastname: Dragsted
authors.forename: Samar
authors.initials: S
authors.lastname: Basu
authors.forename: Ole
authors.initials: O
authors.lastname: Raaschou-Nielsen
authors.forename: Steffen
authors.initials: S
authors.lastname: Loft
mesh_terms: D000280:Administration, Inhalation; D000367:Age Factors; D000368:Aged; D016902:Air Pollution, Indoor / Q000032:analysis / Q000517:prevention & control*; D050197:Atherosclerosis / Q000097:blood / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D016001:Confidence Intervals; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004784:Environmental Monitoring; D005260:Female; D005374:Filtration / Q000379:methods; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood; D019570:Inhalation Exposure; D008297:Male; D008851:Micropore Filters; D008875:Middle Aged; D009585:Nitrogen Dioxide / Q000032:analysis; D018384:Oxidative Stress; D052638:Particulate Matter / Q000633:toxicity*; D011237:Predictive Value of Tests; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012737:Sex Factors; D014657:Vasculitis / Q000097:blood / Q000209:etiology / Q000517:prevention & control*
chemical_list: D018836:Inflammation Mediators; D052638:Particulate Matter; D009585:Nitrogen Dioxide