Predictors of recurrence and long-term patient reported outcomes following surgical repair of anal fistula, a retrospective analysis

Abstract Purpose Surgery for anal fistulas can result in devastating complications, including reoperations and fecal incontinence. There is limited contemporary evidence comparing outcomes since the adoption of the ligation of intersphincteric fistula tract procedure into mainstream practice. The purpose of this study is to compare recurrence rates and long-term outcomes of anal fistula following repair. Methods Data was collected from the electronic medical records or patient reported outcomes from patients aged 18 or older with a primary or recurrent cryptoglandular anal fistula. Primary outcome was recurrence defined as the identification of at least one fistula os or a high clinical suspicion of anal fistula. Secondary outcomes included fecal incontinence and postoperative quality of life. Results A total of 171 patients underwent definitive surgical repairs for their anal fistula. So 66.5% had a simple fistula, and 33.5% had a complex fistula. Of the 171 patients, 12.5% had a recurrence. The recurrence rates were 5.9% for simple fistula and 25.4% for complex fistula. Predictors of recurrence included diabetes mellitus, history of anorectal abscess, complex fistula, and sphincter sparing surgery. LIFT or plug/biologic procedures were both associated with a 50% or greater recurrence rate. No significant differences were found in fecal incontinence or associated quality of life between sphincter sparing or non-sphincter sparing surgical resections. Conclusion The study provides insights into the long-term outcomes of surgical repair for anal fistula. We demonstrate that sphincter sparing operations are associated with increased recurrence, meanwhile, non-sphincter sparing surgeries did not increase the risk of fecal incontinence or worsen quality of life.