title: Platelet aggregability in patients with interstitial pneumonias.
abstract: BACKGROUND
  Recent epidemiological studies have shown that patients with interstitial pneumonia have an increased risk of cardiovascular events. Although the presence of a coagulation/fibrinolysis abnormality in idiopathic pulmonary fibrosis (IPF) has been reported, platelet aggregability has not been evaluated in interstitial pneumonias. This study aimed to investigate platelet aggregability in patients with interstitial pneumonias.
  
  
  METHODS
  This observational cohort study included 59 patients with interstitial pneumonias [19 with IPF, 23 with other idiopathic interstitial pneumonias (IIPs), and 17 with connective tissue disease-associated interstitial pneumonias (CTD-IPs)] and 23 healthy control subjects. ADP- and collagen-induced platelet aggregability was measured together with coagulation/fibrinolysis markers. Whole blood (WB) and platelet rich plasma platelet aggregation were measured using the screen filtration pressure and optical aggregometer techniques, respectively. The platelet aggregation threshold index (PATI) was calculated; a lower PATI indicated enhanced platelet aggregability.
  
  
  RESULTS
  ADP-induced WB-PATI was significantly decreased in CTD-IPs [log WB-PATI median 0.31 (inter-quartile range, 0.07-0.34) μM, n = 17] compared with that in controls [0.35 (0.32-0.45) μM, n = 23] (p < 0.05). However, there was no significant difference in platelet aggregability between the other patient groups and controls. In contrast, d-dimer, thrombin-antithrombin complex, and von Willebrand factor levels were significantly higher in all patient groups compared with those in controls (p < 0.001). Platelet aggregability was not associated with either disease severity or survival.
  
  
  CONCLUSIONS
  Serum coagulation and fibrinolysis markers significantly increased in IIPs and CTD-IPs. In contrast, platelet aggregability was only weakly enhanced in CTDs, but not in IIPs.
authors.affiliation: Assistant professor Department of respiratory medicine Kyoto university hospital. hanta@kuhp.kyoto-u.ac.jp.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Handa
authors.forename: Kizuku
authors.initials: K
authors.lastname: Watanabe
authors.forename: Kiminobu
authors.initials: K
authors.lastname: Tanizawa
authors.forename: Toru
authors.initials: T
authors.lastname: Oga
authors.forename: Kensaku
authors.initials: K
authors.lastname: Aihara
authors.forename: Kohei
authors.initials: K
authors.lastname: Ikezoe
authors.forename: Akihiko
authors.initials: A
authors.lastname: Sokai
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Nakatsuka
authors.forename: Toyohiro
authors.initials: T
authors.lastname: Hirai
authors.forename: Sonoko
authors.initials: S
authors.lastname: Nagai
authors.forename: Kazuo
authors.initials: K
authors.lastname: Chin
authors.forename: Hisanori
authors.initials: H
authors.lastname: Horiuchi
authors.forename: Michiaki
authors.initials: M
authors.lastname: Mishima
mesh_terms: D000368:Aged; D000990:Antithrombin III; D001777:Blood Coagulation; D001780:Blood Coagulation Tests; D016022:Case-Control Studies; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D005342:Fibrinolysis; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000097:blood* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D010447:Peptide Hydrolases / Q000097:blood; D010974:Platelet Aggregation; D010979:Platelet Function Tests; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C046193:antithrombin III-protease complex; C036309:fibrin fragment D; D014841:von Willebrand Factor; D000990:Antithrombin III; D010447:Peptide Hydrolases
keywords: Coagulation factor; Connective tissue disease; Fibrinolysis; Idiopathic pulmonary fibrosis; Screen filtration method; Thrombosis