title: Short-term exposure to high levels of air pollution as a risk factor for acute isolated pulmonary embolism.
abstract: BACKGROUND
  The association between air pollution exposure and occurrence of venous thromboembolism is a matter of debate. This retrospective case-control study investigated the associations between one month's exposure to elevated levels of different pollutants (i.e. PM10, CO, NOx, O3, SO2, Benzene, Benzoapyrene, Nickel, Lead Arsenic) and the development of acute isolated pulmonary embolism (PE).
  
  
  METHODS
  The cases included 33 patients consecutively admitted to Padua Hospital with an objectively proven diagnosis of acute unprovoked (i.e. without predisposing conditions) isolated (i.e. without deep vein thrombosis) PE. The control group consisted of 72 consecutive patients with objectively proven acute provoked (i.e. associated to predisposing conditions) isolated PE. Average mean concentrations of pollutants in the month before PE diagnosis were computed by monitors located at 2 different sites throughout the city of Padua, and were obtained from the Regional Agency for Environmental Protection.
  
  
  RESULTS
  Individuals who had PM10, NOx, Benzene, Benzoapyrene, Cadmium, and Lead exposure equal/above the 2nd tertile, measured in controls, showed a significant increase in the risk of unprovoked PE. In case of PM10 and Benzoapyrene this risk was not affected after adjustment for possible confounders. In fact, in the multivariate logistic regression analysis, the OR values were 5.24 (95% CI: 1.52-18.12) for PM10 and 3.95 (95% CI: 1.06-14.71) for Benzoapyrene exposure in the month before PE diagnosis.
  
  
  CONCLUSIONS
  Our results, although preliminary, identify short-term (i.e. one month) exposure to elevate levels of air pollutants as a possible risk factor for the development of acute isolated PE. Larger studies are needed to confirm our results.
authors.affiliation: Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Spiezia
authors.affiliation: Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Campello
authors.affiliation: Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Bon
authors.affiliation: Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Maggiolo
authors.affiliation: Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Pelizzaro
authors.affiliation: Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua, Italy. Electronic address: paolo.simioni@unipd.it.
authors.forename: Paolo
authors.initials: P
authors.lastname: Simioni
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000009:adverse effects*; D000397:Air Pollution / Q000009:adverse effects*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D052638:Particulate Matter / Q000009:adverse effects*; D011655:Pulmonary Embolism / Q000209:etiology*; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter
keywords: Air pollution; Isolated pulmonary embolism; PM(10); Risk factors