Supplementary Material for: Current Status of Helicobacter pylori Diagnosis and Eradication Therapy in Japan Using a Nationwide Database

Background: Helicobacter pylori infection increases the risk of stomach cancer; therefore, eradication therapy is recommended for infected individuals. Although several methods are recommended for the diagnosis and therapy of H. pylori infection, their frequency and effectiveness have not been fully investigated in Japan. Methods: A nationwide claims database including >1.6 million patients (April 2008 – ­October 2016) in Japan was utilized. We analyzed the distribution of methods for H. pylori diagnosis and therapy, waiting period between eradication and diagnostic test, and success rate of primary therapy. Results: Data for 481,041 patients were extracted. After primary eradication therapy, urea breath test was used for >80% of diagnoses, and antibody measurement for 0.7%. The success rate of primary eradication was >80% for most diagnostic methods and 69.0% for antibody measurement; inappropriately-timed antibody measurement may have contributed to this disparity. The overall success rate of eradication therapy decreased from 2011 to 2014, but increased from 2015, coinciding with launch of the potassium-competitive acid blocker vonoprazan, which showed a higher success rate of eradication than proton-pump inhibitors. Conclusions: Diagnostic tests of H. pylori infection mostly followed Japanese Society for Helicobacter Research guidance, although some antibody measurements were timed inappropriately. Vonoprazan appears to increase the success rate of primary therapy.