Predictors for regression and progression of intestinal metaplasia (IM): A large population-based study from low prevalence area of gastric cancer (IM-predictor trial).

Background: Gastric intestinal metaplasia (IM) can lead to gastric cancer. Until now, there have been limited studies of predictors for regression and progression of IM. This study aimed to determine risk factors associated with regression or progression of IM for guiding proper management and prevention of gastric cancer.

Methods: 2,025 patients undergoing gastroscopy in Thammasat University Hospital, Thailand were enrolled during September 2017-August 2019. Patients' data including baseline characteristics, laboratory results, and histopathology of gastric biopsies from University medical database were extensively reviewed.

Results: 2,025 patients had mean age of 61.3 years and 44.2% were males. Overall H. pylori prevalence was 47.5%. There were 1,551(76.6%) patients with chronic gastritis and 361(17.8%) with IM. Of 400 patients with chronic gastritis having follow-up endoscopy and repeated gastric biopsies, 104(26%) had persistent H. pylori infection and 27(26%) developed IM during mean follow-up time of 24 months. Persistent H. pylori infection was significantly associated with development of IM (OR 3.16, 95%CI 1.56-6.39, p = 0.001). Regression, persistence, and progression of IM were demonstrated in 57.3%, 39.2%, and 3.5% of patients, respectively. Age >65 years, persistent H. pylori infection, and diabetes mellitus were significantly associated with persistent IM or progression to dysplasia with OR 2.47(95%CI 1.33-4.61, p = 0.004), OR 2.64(95%CI 1.13-6.18, p = 0.025), and OR 2.54(95%CI 1.16-5.54, p = 0.019), respectively. Patients without H. pylori infection had more IM regression than patients with persistent infection (60.4%vs.39.4%, p = 0.035). Patients with persistent H. pylori infection significantly had higher IM progression to dysplasia (15.2%vs.2.1%; OR 11.15, 95%CI 1.18-105.24, p = 0.035) than noninfected. During 24 months of study, 30 patients (1.5%) were diagnosed with gastric cancer.

Conclusion: Regression of IM could be achieved by successful H. pylori eradication. Persistent H. pylori infection was significantly associated with development and progression of IM to dysplasia. Age >65 years and diabetes mellitus were also significant predictors for IM progression.