Objectives: If Helicobacter pylori plays an important role in the occurrence of three distinct diseases--gastric cancer, gastric ulcer, and duodenal ulcer--their individual epidemiologic behaviors should show a resemblance to one common pattern.
Methods: To test this hypothesis, birth cohort and linear regression analyses were used to study the US temporal and geographic variations, respectively, of mortality from the three diseases.
Results: US mortality from gastric ulcer in males and duodenal ulcer in both sexes showed a clear-cut peak of occurrence in subjects born around 1885, whereas gastric cancer declined continuously in all Americans born since 1855. The geographic distributions showed a strong correlation between gastric and duodenal ulcer, as opposed to weak correlations between either ulcer type and gastric cancer.
Conclusions: The similarities in the behavior of the three diseases support the idea that identical risk factors play a crucial role in their occurrence. However, the time lag between the decline in mortality from gastric cancer and the decline in mortality from peptic ulcer and their weak geographic correlations indicate that factors besides H pylori must have influenced their epidemiology.