Is duodenal ulcer a seasonal disease? A retrospective endoscopic study of 3105 patients.

The monthly pattern of distribution of endoscopically diagnosed duodenal ulcer disease was evaluated for the years 1975-1989. A retrospective review of 3105 endoscopies performed for peptic disease was recorded and analyzed. Among them, 2020 endoscopies revealed duodenal bulb deformity, and 1035 revealed the presence of acute duodenal ulcer. Chi-square analysis of the data for goodness of fit revealed statistical differences for certain months. Slightly more patients with chronic deformity presented in June and November, whereas more patients with acute duodenal ulcer presented in July, November, and December (p < 0.001). The ratio of acute to chronic disease was nearly constant throughout the year. The Edwards chi 2 test for seasonal trends did not reveal any seasonality (p > 0.75). The differences observed in June-July and November-December, as compared with the rest of the year, were so small that they should not be relied upon for the clinical management of peptic disease.