Shift work increases the frequency of duodenal ulcer in H pylori infected workers

Aim: To evaluate whether shift work is associated with an increased rate of peptic ulcer in H pylori infected workers. Methods: During a two year period, consecutive dyspeptic workers underwent non-invasive evaluation of H pylori status by means of urea C-13 breath test or stool testing. Those testing positive were included in the study and divided into two main categories: day-time workers and shift workers. An upper gastrointestinal endoscopy was performed in all workers, and biopsy specimens were taken from the stomach to confirm the presence of H pylori infection ( culture and histology). Results: A total of 247 day-time workers and 101 shift workers were included. The prevalence of duodenal ulcer was significantly higher in shift workers than in day-time workers ( 29 of 101 v 23 of 247; OR=3.92, 95% CI 2.13 to 7.21), and persisted after multivariate analysis, taking into account possible confounding factors ( OR = 3.96, 95% CI 2.10 to 7.47). Conclusion: Shift work increases the ulcerogenic potential of H pylori infection and should be considered a risk factor for duodenal ulcer in infected shift workers. Treatment of infection in this high risk group may improve the health of workers and may reduce the economic impact of peptic ulcer.