Proton pump inhibitors and the risk of colorectal cancer.
BACKGROUND
Proton pump inhibitor (PPI) use is associated with increased serum gastrin levels and bacterial overgrowth, resulting in more toxic bile salt formation. Concern has risen that these factors may increase the risk of developing colorectal neoplasia.


OBJECTIVE
To investigate the association between the use of PPIs and the risk of colorectal cancer.


METHODS
A population-based case-control study was conducted within the Dutch Primary Care Information (IPCI) database over the period 1996-2005. Cases with colorectal cancer were matched with up to 20 controls on age, gender, calendar time, and duration of follow-up prior to diagnosis. Cumulative exposure to PPIs was assessed in the 5 yr prior to diagnosis with a 1-yr lag time analysis. We calculated adjusted odds ratios (OR) with 95% confidence intervals (95% CI) using multivariate, conditional logistic regression analysis.


RESULTS
Within the source population of 457,024 persons, we identified 595 colorectal cancer cases. The odds of colorectal cancer were not increased among patients ever using PPIs compared with patients who never used PPIs (OR 0.85, 95% CI 0.63-1.16). Also, the use of PPIs for >365 days was not associated with a greater risk of colorectal cancer (OR 0.79, 95% CI 0.44-1.41) compared with nonusers. The odds of colorectal cancer in neither the right nor the left hemicolon were significantly increased in patients using PPIs.


CONCLUSIONS
The present study indicates no association between PPI use and the risk of colorectal cancer. Larger numbers of long-term PPI users are needed to confirm the absence of a risk-increasing effect of long-term PPI exposure.
van Soest
Eva M
EM
Department of Gastroenterology and Hepatology, Erasmus Unievrsity Medical Center, Rotterdam, The Netherlands.
van Rossum
Leo G M
LG
Dieleman
Jeanne P
JP
van Oijen
Martijn G H
MG
Siersema
Peter D
PD
Sturkenboom
Miriam C J M
MC
Kuipers
Ernst J
EJ
D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D054328:Proton Pump Inhibitors / Q000009:adverse effects*; D012306:Risk
D054328:Proton Pump Inhibitors