Prevalence of previous appendectomy among patients needing gastrointestinal endoscopy.

BACKGROUND The appendix may be an immune modulator of the gut, and its absence may lead to an increase in gastrointestinal illnesses. If this is true, we may expect patients needing endoscopy to have a higher prevalence of previous appendectomy. METHODS We did a case-control study at the University of Oklahoma Hospital for 13 months. Subjects having endoscopic evaluation at the University of Oklahoma Hospital formed the study group. Patients seen at the general medicine clinic of the University of Oklahoma served as controls. We recorded the patient's name, age, sex, race, history of smoking, and history of appendectomy or tonsillectomy. RESULTS The endoscopy group had 524 patients; 469 patients were in the control group. There were no differences based on race or history of smoking. There was greater prevalence of previous appendectomy in the endoscopy group (33.46% vs. 20.55%). The prevalence of tonsillectomy was 29.28% in the study group vs. 21.61% among the controls. Multiple regression revealed that history of appendectomy and not tonsillectomy was related to the performance of endoscopy. CONCLUSION History of appendectomy is associated with greater performance of endoscopy.