Gastroduodenal endoscopy was performed, and the findings were independently scored according to the Kyoto classification of gastritis and the Kimura-Takemoto classification by two endoscopists (9 (link),15 ). The Kimura-Takemoto gastric atrophy classification scores atrophy as six grades: Closed (C)-I, C-II, C-III, and Open (O)-I, O-II, and O-III (15 ). In this classification, C-I, C-II, and C-III denote closed-type atrophic patterns, with a margin between the non-atrophic fundic mucosa and atrophic mucosa located in the lesser curvature of the stomach; and O-I, O-II, and O-III denote open-type atrophic patterns, whose margin does not cross the lesser curvature. According to the Kyoto classification of gastritis, patients are classified into three groups based on endoscopic findings: H. pylori-negative patients (no gastritis), current H. pylori-positive patients (active gastritis), and previous H. pylori-infected patients (inactive gastritis). The total score involves five parameters of gastritis, including atrophy (Kimura-Takemoto classification CI = Kyoto A0, CII & C-III = Kyoto A1, and OI-OIII = Kyoto A2), intestinal metaplasia (none: IM0, within antrum: IM1, and up to corpus: IM2), hypertrophy of gastric folds (negative: H0, positive: H1), nodularity (negative: N0, positive: N1), and diffuse redness (negative: DR0, mild: DR1, severe: DR2). These scores were independently calculated for all subjects by two expert endoscopists after endoscopy (Table 1). During endoscopy, more than 40 pictures were taken by an expert endoscopist. When the two endoscopists differed on the score assigned, they arrived at a consensus by reviewing the pictures. The status of intestinal metaplasia was diagnosed using image-enhanced endoscopy, such as narrow band imaging, but not pathological evaluations.