title: Ambient air pollution and oxygen saturation.
abstract: We investigated the association between fine particulate air pollution and oxygen saturation as measured with a peripheral oxygen saturation monitor during a 12-week repeated-measures study of 28 older Boston residents. Oxygen saturation and air pollution particulates with a mean diameter less than or equal to 2.5 microm were measured continuously during a protocol of rest, standing, exercise, postexercise rest, and 20 cycles of slow, paced breathing. In fixed-effect models, mean pollution concentration was associated with reduced oxygen saturation during the baseline rest period (6 hours: mean, -0.173%; 95% confidence interval [CI], -0.345 to -0.001), postexercise (6 hours: mean, -0.173%; 95% CI, -0.332 to -0.014), with a trend toward decrease during postexercise paced breathing (6 hours: mean, -0.142%; 95% CI, -0.292 to 0.007) but not during exercise. Participants taking beta-blockers had a greater pollution-related decrease in oxygen saturation at rest (6 hours: mean, -0.769%; 95% CI, -1.210 to -0.327) (interaction for particulates with a mean diameter less than or equal to 2.5 microm by beta-blocker, p < 0.0005) than did those not taking beta-blockers (p > 0.25). The reduction in oxygen saturation associated with air pollution may result from subtle particulate-related pulmonary vascular and/or inflammatory changes. Further investigation may contribute to our understanding of the mechanisms through which particulates may increase respiratory and cardiac morbidity among vulnerable populations.
authors.affiliation: Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 181 Longwood Avenue, Boston, MA 02115, USA. redld@channing.harvard.edu
authors.forename: Dawn L
authors.initials: DL
authors.lastname: DeMeo
authors.forename: Antonella
authors.initials: A
authors.lastname: Zanobetti
authors.forename: Augusto A
authors.initials: AA
authors.lastname: Litonjua
authors.forename: Brent A
authors.initials: BA
authors.lastname: Coull
authors.forename: Joel
authors.initials: J
authors.lastname: Schwartz
authors.forename: Diane R
authors.initials: DR
authors.lastname: Gold
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D001784:Blood Gas Analysis; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D015444:Exercise / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D010316:Particle Size; D012146:Rest / Q000502:physiology
chemical_list: D000319:Adrenergic beta-Antagonists; D000393:Air Pollutants; D010100:Oxygen