Abstract
IMPORTANCE: Fecal incontinence (FI) affects up to 8% of adults and substantially impairs quality of life. Surgical options carry higher risk and cost, and evidence for minimally invasive alternatives, such as anal inserts, is limited. OBJECTIVE: To determine whether a novel anal insert achieves a clinically meaningful reduction in FI severity compared with usual care. DESIGN, SETTING, AND PARTICIPANTS: This multicenter, open-label, randomized clinical superiority trial was conducted from May 26, 2021, to August 1, 2024, with 8 weeks of treatment and 4 weeks of follow-up at 2 outpatient hospital clinics in the Netherlands. Participants were individuals aged 16 to 90 years with FI (Rome IV criteria) with at least 1 FI episode during a 14-day run-in period. Data were analyzed from August 2 to December 20, 2024. INTERVENTION: A single-use anal insert compared with usual care alone. MAIN OUTCOMES AND MEASURES: The primary outcome was proportion of participants achieving a reduction of at least 3 points in the St Mark's incontinence score from baseline to 8 weeks. Secondary outcomes included FI-specific quality of life, anxiety, depression, adverse events, and weekly FI episodes (post hoc outcome). RESULTS: A total of 73 participants were screened and 72 were randomized (60 [83.3%] female; mean [SD] age, 67.3 [9.8] years]), with 35 participants receiving the insert and 37 receiving usual care. There was no significant difference in reduction in St Mark's score (9 participants [25.7%] in the insert group vs 7 participants [18.9%] in the control group; relative risk, 1.36 [95% CI, 0.57 to 3.25]). Coping (mean between-group difference, 0.19 [95% CI, 0.03 to 0.35]) and depression (mean between-group difference, 0.15 [95% CI, 0.01 to 0.30]) domains of the quality-of-life assessment improved more with the insert group, whereas lifestyle and embarrassment domains of the quality-of-life assessment, anxiety, and overall depression showed no between-group differences. The insert reduced FI episodes (estimated mean difference, -3.09 [95% CI, -4.39 to -1.75] episodes per week) and increased the proportion achieving more than 50% reduction in FI episodes. No serious adverse events occurred; device-related adverse events were common but mild. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, the primary outcome of achieving a reduction of at least 3 points in St Mark's incontinence score was not met; however, the anal insert improved selected FI-specific quality-of-life domains. These findings suggest that the device may provide a minimally invasive option for selected patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04657588.