title: Pernicious anemia and colorectal cancer risk - A nested case-control study.
abstract: BACKGROUND
  Hypergastrinemia was shown to stimulate colonic epithelial cell proliferation.
  
  
  OBJECTIVE
  To evaluate the association between pernicious anemia (PA), a disease with hypergastrinemia, and colorectal cancer (CRC) risk.
  
  
  METHODS
  We conducted a nested case-control study within a large database from the UK. Cases were defined as all individuals in the cohort with at least one medical code for CRC. Controls were selected based on incidence-density sampling. For each case, up to four eligible controls were matched on age at diagnosis, sex, practice-site, and both duration and calendar time of follow-up. Exposure of interest was diagnosis of PA prior to CRC diagnosis date. The primary analysis was a multivariable conditional logistic regression.
  
  
  RESULTS
  Our study included 22,098 CRC cases and 85,969 matched controls. We identified 154 (0.70%) cases and 563 (0.65%) controls with past history of PA. The adjusted OR for the association between PA and CRC risk was 1.02 (95% CI 0.85-1.22). There was no difference in the results after stratification according to sex. In a sensitivity analysis only among individuals without chronic use of proton pump inhibitors (PPIs) the adjusted OR was 1.14 (95% CI 0.90-1.45). There was no association between duration of PA and CRC risk.
  
  
  CONCLUSIONS
  PA is not associated with higher CRC risk.
authors.affiliation: Division of Gastroenterology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Ben
authors.initials: B
authors.lastname: Boursi
authors.affiliation: Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Division of Hematology/Oncology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Ronac
authors.initials: R
authors.lastname: Mamtani
authors.affiliation: Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Haynes
authors.affiliation: Division of Gastroenterology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA; Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA. Electronic address: yangy@mail.med.upenn.edu.
authors.forename: Yu-Xiao
authors.initials: YX
authors.lastname: Yang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000752:Anemia, Pernicious / Q000453:epidemiology*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000150:complications*; D016208:Databases, Factual; D005260:Female; D005755:Gastrins / Q000097:blood*; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D054328:Proton Pump Inhibitors / Q000009:adverse effects*; D012307:Risk Factors; D012737:Sex Factors; D006113:United Kingdom
chemical_list: D005755:Gastrins; D054328:Proton Pump Inhibitors
keywords: Colon cancer; Gastrin; Pernicious anemia; Proton pump inhibitors