title: Air pollution related prothrombotic changes in persons with diabetes.
abstract: BACKGROUND
  Population studies suggest that persons with diabetes are more sensitive to the effects of particulate matter (PM) air pollution. However, the biological mechanisms of a possible prothrombotic effect underlying this enhanced susceptibility remain largely unknown.
  
  
  OBJECTIVE
  We hypothesized that exposure to PM causes prothrombotic changes in persons with diabetes, possibly via systemic inflammation.
  
  
  METHODS
  Our study included 137 nonsmoking adults with diabetes who were outpatients at the University Hospital Leuven. Recent exposure (2 hr before examination) to ambient PM was measured at the entrance of the hospital. Individual chronic exposure to PM was assessed by measuring the area occupied by carbon in airway macrophages obtained by sputum induction. Platelet function was measured ex vivo with the PFA-100 platelet function analyzer, which simulates a damaged blood vessel; we analyzed the function of platelets in primary hemostasis under high shear conditions. Total and differential blood leukocytes were counted.
  
  
  RESULTS
  Independent of antiplatelet medication, an interquartile range (IQR) increase of 39.2 microg/m3 in PM10 (PM with aerodynamic diameter <or= 10 microm) concentration measured 2 hr before the clinical examination (recent exposure) was associated with a decrease of 21.1 sec [95% confidence interval (CI), 35.3 to 6.8] in the PFA-100 closure time (i.e., increased platelet activation) and an increase in blood leukocytes of 512 per microliter of blood (95% CI, 45.2979). Each area increase of 0.25 microm2 (IQR) in carbon load of airway macrophages (chronic exposure) was associated with an increase of 687 leukocytes per microliter of blood (95% CI, 2241,150).
  
  
  CONCLUSIONS
  A relevant increase in recent PM exposure was associated with a change in platelet function toward a greater prothrombotic tendency. The magnitude of the change was about two-thirds (in the opposite direction) of the average effect of antiplatelet medication. Diabetic patients showed evidence of proinflammatory response to both recent and chronic exposure to PM air pollution.
authors.affiliation: Occupational and Environmental Medicine, Unit of Lung Toxicology, Katholique Universiteit Leuven, Leuven, Belgium.
authors.forename: Lotte
authors.initials: L
authors.lastname: Jacobs
authors.forename: Jan
authors.initials: J
authors.lastname: Emmerechts
authors.forename: Chantal
authors.initials: C
authors.lastname: Mathieu
authors.forename: Marc F
authors.initials: MF
authors.lastname: Hoylaerts
authors.forename: Frans
authors.initials: F
authors.lastname: Fierens
authors.forename: Peter H
authors.initials: PH
authors.lastname: Hoet
authors.forename: Benoit
authors.initials: B
authors.lastname: Nemery
authors.forename: Tim S
authors.initials: TS
authors.lastname: Nawrot
mesh_terms: D000328:Adult; D000368:Aged; D000397:Air Pollution / Q000009:adverse effects*; D001792:Blood Platelets / Q000187:drug effects* / Q000502:physiology; D003920:Diabetes Mellitus / Q000097:blood* / Q000276:immunology / Q000378:metabolism*; D004781:Environmental Exposure / Q000009:adverse effects; D005260:Female; D006801:Humans; D007249:Inflammation / Q000139:chemically induced; D007962:Leukocytes / Q000187:drug effects / Q000502:physiology; D008297:Male; D008875:Middle Aged; D052638:Particulate Matter / Q000009:adverse effects; D010979:Platelet Function Tests
chemical_list: D052638:Particulate Matter