A new study suggests that patients who have their appendix removed are at increased risk of Crohn's disease.
The cause of Crohn's disease, a painful condition involving inflammation of the small intestine, remains unknown. But Swedish researchers now reveal an intriguing link between appendicitis and Crohn's disease.

They followed up 212,218 patients, half of whom had had appendectomies between 1964 and 1993. A total of 613 patients were diagnosed with Crohn's disease, and of these 56 per cent had a history of appendectomy.

The data shows that appendectomy increases the risk of Crohn's disease by three times. However, patients should not be alarmed - for the absolute risk of developing Crohn's disease in ten years is less than two patients per 1,000 appendix operations. There is no suggestion that the operation itself is linked with Crohn's disease - it is having appendicitis that is the relevant factor. Women, those with a perforated appendix, and those who had their appendix out after their tenth birthday had the higher risk of Crohn's disease. This study suggests a new avenue of research into the causes of Crohn's disease.