[Effects of helicobacter pylori infection on gastric mucosaia: a 5-year cohort study].

OBJECTIVE: To observe the changes in severity of gastritis and intestinal metaplasia by following-up a group of patients for 5 years to explore the effect of Helicobacter pylori (Hp) on the disease process. METHODS: In this prospective cohort study, patients were selected from 7 enterprises by regular endoscopic examination in Zhongshan Hospital from July 1993 to June 1994. Recruited patients were those with upper abdominal discomfort and diagnosed as chronic gastritis endoscopically and pathologically. Hp-positive patients were given either eradication therapy or symptomatic treatment according to their willingness. All the patients were followed-up for 5 years. RESULTS: Among the total 75 patients (30 were Hp positive and 45 were Hp negative), 24 Hp-negative cases were recruited as control group. Among 45 originally Hp-positive patients, except for one drop-out case, 16 cases in whom Hp was eradicated were defined as the eradication group and the remaining 28 patients with persistent Hp infection were assigned into the infection group. In the control group, in only 17% approximately 33% of patients the gastritis was worsened. In the infection group, 29% approximately 42% of patients had no changes in their gastritis severity, however in 43% approximately 57% of patients the disease was worsened. While in the eradication group, in 50% of patients the disease was improved, and in only 25% of patients the disease was aggravated, with an aggravalion rate much lower than that in infection group. For intestinal metaplasia (IM), in the control group, 16% approximately 25% of patients had their IM aggravated, but no changes occurred in 50% approximately 67% of patients. In the infection group, the rate of IM worsening increased to 43%-57%, while no IM worsening could be seen in eradication group, 75.0% of the patients in this group maintained their original status. CONCLUSIONS: Eradication of Hp could not only ameliorate the severity of gastritis, but also inhibit the development of IM.