TY - JOUR T1 - Association between proton pump inhibitor use and gastric cancer: a population-based cohort study using two different types of nationwide databases in Korea JF - Gut JO - Gut DO - 10.1136/gutjnl-2020-323845 SP - gutjnl-2020-323845 AU - Seung In Seo AU - Chan Hyuk Park AU - Seng Chan You AU - Jae Young Kim AU - Kyung Joo Lee AU - Jinseob Kim AU - Yerim Kim AU - Jong Jin Yoo AU - Won-Woo Seo AU - Hyung Seok Lee AU - Woon Geon Shin Y1 - 2021/05/10 UR - http://gut.bmj.com/content/early/2021/05/11/gutjnl-2020-323845.abstract N2 - Objective The association between proton pump inhibitor (PPI) use and gastric cancer related to Helicobacter pylori eradication has not been fully investigated in geographical regions with high risk of gastric cancer. We aimed to evaluate the association between PPIs and gastric cancer in Korea.Design This study analysed the original and common data model versions of the Korean National Health Insurance Service database from 2002 to 2013. We compared the incidence rates of gastric cancer after 1-year drug exposure, between new users of PPIs and other drugs excluding PPIs, by Cox proportional hazards model. We also analysed the incidence of gastric cancer among PPI users after H. pylori eradication.Results The analysis included 11 741 patients in matched PPI and non-PPI cohorts after large-scale propensity score matching. During a median follow-up of 4.3 years, PPI use was associated with a 2.37-fold increased incidence of gastric cancer (PPI≥30 days vs non-PPI; 118/51 813 person-years vs 40/49 729 person-years; HR 2.37, 95% CI 1.56 to 3.68, p=0.001). The incidence rates of gastric cancer showed an increasing trend parallel to the duration of PPI use. In H. pylori-eradicated subjects, the incidence of gastric cancer was significantly associated with PPI use over 180 days compared with the non-PPI group (PPI≥180 days vs non-PPI; 30/12 470 person-years vs 9/7814 person-years; HR 2.22, 95% CI 1.05 to 4.67, p=0.036).Conclusion PPI use was associated with gastric cancer, regardless of H. pylori eradication status. Long-term PPIs should be used with caution in high-risk regions for gastric cancer.Data are available upon reasonable request. The analytic R code is available from the author WGS (e-mail, sgun9139@gmail.com). ER -