Prescription drugs associated with false-positive results when using faecal immunochemical tests for colorectal cancer screening

Dig Liver Dis. 2016 Oct;48(10):1249-54. doi: 10.1016/j.dld.2016.06.011. Epub 2016 Jun 21.


Background: The most common side effect in population screening programmes is a false-positive result which leads to unnecessary risks and costs.

Aims: To identify factors associated with false-positive results in a colorectal cancer screening programme with the faecal immunochemical test (FIT).

Methods: Cross-sectional study of 472 participants with a positive FIT who underwent colonoscopy for confirmation of diagnosis between 2013 and 2014. A false-positive result was defined as having a positive FIT (≥20μg haemoglobin per gram of faeces) and follow-up colonoscopy without intermediate/high-risk lesions or cancer.

Results: Women showed a two-fold increased likelihood of a false-positive result compared with men (adjusted OR, 2.3; 95%CI, 1.5-3.4), but no female-specific factor was identified. The other variables associated with a false-positive result were successive screening (adjusted OR, 1.5; 95%CI, 1.0-2.2), anal disorders (adjusted OR, 3.1; 95%CI, 2.1-4.5) and the use of proton pump inhibitors (adjusted OR, 1.8; 95%CI, 1.1-2.9). Successive screening and proton pump inhibitor use were associated with FP in men. None of the other drugs were related to a false-positive FIT.

Conclusion: Concurrent use of proton pump inhibitors at the time of FIT might increase the likelihood of a false-positive result. Further investigation is needed to determine whether discontinuing them could decrease the false-positive rate.

Keywords: Colorectal cancer screening; Faecal immunochemical test; False positive; Screening.

MeSH terms

  • Aged
  • Anus Diseases / complications
  • Colonoscopy / methods
  • Colorectal Neoplasms / diagnosis*
  • Cross-Sectional Studies
  • Early Detection of Cancer / methods*
  • False Positive Reactions
  • Feces / chemistry
  • Female
  • Hemoglobins / analysis
  • Humans
  • Logistic Models
  • Male
  • Mass Screening / methods*
  • Middle Aged
  • Multivariate Analysis
  • Occult Blood
  • Prescription Drugs / isolation & purification
  • Proton Pump Inhibitors / isolation & purification*
  • Risk Factors
  • Spain


  • Hemoglobins
  • Prescription Drugs
  • Proton Pump Inhibitors