Helicobacter pylori epidemiology in relation to peptic ulcer and gastric cancer in south and north China.

Peptic ulcer disease is twice as common in people living in South China when compared with those in North China. However, the gastric cancer rate in North China is three times that of South China. The overall Helicobacter pylori prevalence rate is similar in North and South China populations and it is higher than Caucasians living in Western societies. However, there is a significantly higher prevalence of H. pylori seropositivity among those who live in the high gastric cancer areas of China. On the other hand, there is no significant difference in the H. pylori positive rate in the peptic ulcer disease patients between the two regions of China. Other permissive/associated co-factors in the development of peptic ulcer disease or gastric cancer remain unknown at this stage.