title: Antithrombotic drug does not affect the positive predictive value of an immunochemical fecal occult blood test.
abstract: OBJECTIVE
  Antithrombotic drugs may affect the diagnostic performance of immunochemical fecal occult blood test (iFOBT) for colorectal cancer (CRC) screening. The aim of the present study was to assess the effect of antithrombotic drugs on the diagnostic performance of iFOBT.
  
  
  METHODS
  We analyzed 1016 patients who underwent colonoscopy for positive iFOBT. Patients were classified as follows: patients who had advanced neoplasms detected and those who did not; patients who had cancers detected and those who did not; patients who had any neoplasms detected and those who did not. We compared the following factors between two paired groups: sex, age, endoscopists' experience, and antithrombotic drug usage.
  
  
  RESULTS
  A total of 139 patients were taking antithrombotic drugs (13.7%). Advanced neoplasms, cancers, and any neoplasms were detected in 196 (19.3%), 59 (5.8%), and 490 (48.2%)patients, respectively. There were no higher detection rates in the antithrombotic drug (-) group than in the (+) group (advanced neoplasms: 19.3% vs 19.4%, P=1.000; cancers: 5.8% vs 5.8%, P=1.000; any neoplasms: 48.4% vs 47.5%, P=0.856). Multivariate logistic regression analysis revealed that none of aspirin, warfarin, or other antithrombotic drugs was a significant factor for advanced neoplasms (95% CI 0.350-1.216, P=0.179; 95% CI 0.421-1.899, P=0.772; 95% CI 0.323-1.810, P=0.764, respectively). As to cancers and any neoplasms, no antithrombotic drug also proved to be a significant factor.
  
  
  CONCLUSIONS
  The present study demonstrated that the positive predictive value of iFOBT was not affected by ongoing antithrombotic therapy.
authors: Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan; Department of Gastroenterology, NTT Medical Center Tokyo, Tokyo, Japan.
authors: Yosuke
authors: Y
authors: Tsuji
authors: Toshiaki
authors: T
authors: Gunji
authors: Hajime
authors: H
authors: Sato
authors: Akiko
authors: A
authors: Ono
authors: Takafumi
authors: T
authors: Ito
authors: Ken
authors: K
authors: Ohata
authors: Nobutake
authors: N
authors: Yamamichi
authors: Mitsuhiro
authors: M
authors: Fujishiro
authors: Nobuyuki
authors: N
authors: Matsuhashi
authors: Kazuhiko
authors: K
authors: Koike
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003113:Colonoscopy / Q000379:methods; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D016001:Confidence Intervals; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D055088:Early Detection of Cancer / Q000379:methods; D005189:False Positive Reactions; D005260:Female; D005343:Fibrinolytic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D007564:Japan; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D009780:Occult Blood; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity
chemical_list: D005343:Fibrinolytic Agents; D011933:Reagent Kits, Diagnostic
keywords: antithrombotic agent; cancer screening; colonic neoplasm; colonoscopy; false-positive reaction