Association between intestinal functional disorders and anal fistula: evidence from a retrospective case-control study.
Chronic diarrhea before diagnosis was associated with higher odds of anal fistula.
Association between intestinal functional disorders and anal fistula: evidence from a retrospective case-control study.
Clinical observations indicate that some individuals experience bowel dysfunction, such as diarrhea or constipation, prior to the diagnosis of anal fistula (anal fistula).
This study aimed to evaluate the association between pre-diagnostic bowel dysfunction and anal fistula and to explore whether such associations differ across anal fistula anatomical subtypes.
We conducted a retrospective hospital-based case-control study including 251 patients with newly diagnosed anal fistula between July 2024 and July 2025.
Pre-existing bowel dysfunction was associated with a higher likelihood of developing anal fistula ( p < 0.05).
Smoking, alcohol consumption, prolonged sedentary or standing occupations, and higher body mass index (BMI) were also associated with anal fistula.
In exploratory analyses of anal fistula subtypes, diarrhea showed modest heterogeneity across anatomical classifications, whereas constipation showed no significant variation across subtypes.
This retrospective case-control study indicates that pre-existing intestinal functional disorders, particularly chronic diarrhea, are associated with a higher likelihood of anal fistula, with the association appearing more pronounced among low anal fistulas.
No consistent subtype-specific pattern was observed overall, although diarrhea showed modest heterogeneity across anatomical classifications in exploratory analyses.