A team from Sweden and the USA investigated the relationship between appendectomy and ulcerative colitis risk.
The researchers studied a cohort of 212,963 patients who underwent appendectomy before the age of 50 years between 1964 and 1993, and a cohort of matched controls, who were identified from the Swedish Inpatient Register and the nationwide census.
The cohort was followed until 1995 for any subsequent diagnosis of ulcerative colitis
Patients who underwent appendectomy for appendicitis and mesenteric lymphadenitis were found to have a low risk of ulcerative colitis. For patients with perforated appendicitis, non-perforated appendicitis, and mesenteric lymphadenitis, the adjusted hazard ratios were 0.58, 0.76, and 0.57, respectively.
In contrast, patients who underwent appendectomy for nonspecific abdominal pain had the same risk of ulcerative colitis as the controls (adjusted hazard ratio, 1.06).
|Risk of developing ulcerative colitis following appendectomy for various conditions:|
Perforated appendicitis: 0.58
|New England Journal of Medicine|
For the patients who had appendicitis, an inverse relation with the risk of ulcerative colitis was found only for those who underwent surgery before the age of 20 years.
Dr Roland Andersson, of the Ryhov Hospital, Jonkoping, Sweden, said on behalf of the group, "Appendectomy for an inflammatory condition (appendicitis or lymphadenitis), but not for nonspecific abdominal pain, is associated with a low risk of subsequent ulcerative colitis. This inverse relation is limited to patients who undergo surgery before the age of 20 years."