Protective effect of appendectomy against the onset of ulcerative colitis: A case-control study

Previous studies suggest that appendectomy has a protective effect against ulcerative colitis (UC); however, relatively few studies focusing on this topic have been reported in China.

To explore the correlation between appendectomy and the onset of UC.

A total of 313 patients with newly diagnosed UC and 313 healthy individuals were selected for this study. According to whether their appendix was removed before the diagnosis of UC, patients were divided into appendectomized and non-appendectomized groups. Their general clinical data, appendectomy history, disease severity, extent of involvement, and blood routine test results were collected to evaluate the relationship between appendectomy and the onset of UC.

The study revealed that the average time interval for the diagnosis of UC after appendectomy was 14.72 ± 13.87 years. 55.81% patients were diagnosed with UC five years after appendectomy. Among them, eight patients underwent appendectomy before the age of 20 years and were diagnosed with UC five years later. In the appendectomized group, the onset age of UC was higher, and the degree of disease activity was significantly lower. This group had a higher proportion of patients in clinical remission or with mild disease and a lower proportion of patients with severe disease. The extent of lesions in the appendectomized group was limited, with a higher proportion of E1 and E2, whereas a lower proportion of E3 lesions.

Appendectomy may delay the onset of UC, reduce disease severity, and lessen the scope of involvement.