title: A case-crossover study of ambient particulate matter and cardiovascular and respiratory medical encounters among US military personnel deployed to southwest Asia.
abstract: OBJECTIVE
  To evaluate the impact of ambient particulate matter (PM) on acute cardiorespiratory morbidity among US military personnel in southwest Asia.
  
  
  METHODS
  We linked ambient PM data collected between December 2005 and June 2007 with personnel, medical, and meteorological data. We implemented a case-crossover analysis to estimate base-specific associations and pooled those estimates using meta-analytic methods.
  
  
  RESULTS
  The adjusted odds ratios for a 10-μg/m increase in ambient PM2.5 and a qualifying medical encounter were 0.92 (95% confidence interval [CI]: 0.77 to 1.11) and 1.01 (95% CI: 0.95 to 1.07) for the current (lag_0) and previous (lag_1) days. The estimates for a 10-μg/m increase in PM10 were 0.99 (95% CI: 0.97 to 1.03) at lag_0, and 1.00 (95% CI: 0.97 to 1.02) at lag_1.
  
  
  CONCLUSIONS
  No statistically significant associations between PM and cardiorespiratory outcomes were observed in this young, relatively healthy, deployed military population.
authors.affiliation: Environmental Medicine Program, US Army Public Health Command (Provisional), 5158 Black Hawk Rd., Aberdeen Proving Ground, MD 21010, USA. joseph.h.abraham@us.army.mil
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Abraham
authors.forename: Coleen P
authors.initials: CP
authors.lastname: Baird
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001211:Asia, Western; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008889:Military Personnel / Q000706:statistics & numerical data*; D052638:Particulate Matter / Q000633:toxicity*; D012140:Respiratory Tract Diseases / Q000453:epidemiology / Q000209:etiology*; D055815:Young Adult
chemical_list: D052638:Particulate Matter