Short- and long-term outcome of sphincteroplasty for anal incontinence: Results from the Norwegian Registry of Anal Incontinence

The purpose of this study was to assess outcome after 1 and 5 years in patients who had undergone sphincteroplasty for anal incontinence (AI) in Norway. The study was conducted as a retrospective cohort study based on prospectively recorded data from the Norwegian Registry of Anal Incontinence. AI was quantified using the St. Mark’s score. Quality of life (QoL) was assessed with a simple visual analog scale with range 0 – 10. Primary endpoints were reduction in St. Mark’s score and QoL score at follow-up. Some 75 patients had available results at year 1 follow-up, and 34 patients at year 5. Between baseline and year 1 there was a mean decrease in St. Mark’s score of 3.9 points (p < 0.001) and an increase in QoL-score of 0.4 points (p=0.282). Between year 1 and year 5 mean St. Mark’s score increased by 1.0 points (p=0.359), while the QoL decreased by 1.7 points (p=0.020). Comparing baseline with year 5, there was still a mean decrease in the St. Mark´s score (p < 0.001). A low St. Mark’s score at baseline was statistically significantly associated with less reduction in St. Mark’s score at year 1 (p < 0.001), and patients with a baseline St. Mark’s score of 9 or less experienced a mean St Mark’s score increase of 0.25 point (p=0.901). Neither age, menopause or ultrasonographic extent of sphincter defect prior to surgery affected outcome. Patients with a baseline St. Mark’s score of 9 or less have little to no benefit from sphincteroplasty for AI.