Helicobacter pylori Eradication Improves Gastric Atrophy and Intestinal Metaplasia in Long-Term Observation

BACKGROUND AND AIM: Helicobacter pylori has been shown to cause atrophic gastritis and intestinal metaplasia (IM), both of which are precancerous lesions. To clarify the mechanism by which H. pylori eradication prevents gastric cancer, we monitored atrophy and IM improvement in gastric mucosa over a long period after H. pylori eradication. METHODS: We monitored 118 patients (72 males, 46 females; mean age 61.3 ± 5.1 years) for a mean of 8.6 years (range 5-13) after successful H. pylori eradication. Biopsy specimens were taken from the greater curvatures of the antrum (A2) and the corpus (B2). RESULTS: Atrophy was significantly decreased in patients with successful H. pylori eradication, both at A2 (from 1.60 ± 0.09 to 1.02 ± 0.08; p < 0.001) and B2 (from 0.71 ± 0.10 to 0.02 ± 0.02; p < 0.001), and IM score was significantly decreased at B2 (from 0.17 ± 0.12 to 0.00 ± 0.00; p < 0.05), but not at A2 (from 0.60 ± 0.11 to 0.43 ± 0.09; p = NS). In patients without successful eradication, however, there were no differences in scores over time. Before eradication, IM score was significantly higher in males than in females, both at A2 (0.81 ± 0.12 vs. 0.25 ± 0.10; p < 0.05) and B2 (0.32 ± 0.08 vs. 0.07 ± 0.04; p < 0.05). CONCLUSION: We were able to monitor the gastric mucosa for a mean of 8.6 years after H. pylori eradication, the longest period reported to date. Significant improvements in gastric atrophy and IM after H. pylori eradication may decrease the risk of gastric cancer.