The prevalence of Helicobacter pylori in nonulcer dyspepsia. Importance of stratification according to age Helicobacter pylori (formerly Campylobacter pylori) is causally related to active antral gastritis and is highly associated with duodenal and gastric ulcers. However, the relationship of H pylori to nonulcer dyspepsia is less clear. We determined the presence of H pylori in unselected patients who were undergoing upper gastrointestinal tract endoscopy, and we found a prevalence of 37% in 110 patients with nonulcer dyspepsia that was similar to previous data. Patients with nonulcer dyspepsia who had H pylori were found to be significantly older than patients with nonulcer dyspepsia who did not have H pylori. In addition, when stratified according to age, we detected an increased prevalence of H pylori in patients with nonulcer dyspepsia with increasing age, similar to that reported for asymptomatic control populations. This finding casts doubt as to the causal role of H pylori for most patients with nonulcer dyspepsia and stresses the importance of considering epidemiologic factors, such as age, when evaluating the role of H pylori in specific disease states. 