Transanal irrigation in patients affected by low anterior resection syndrome (LARS): Long-term results from an Italian national study

Background: Low Anterior Resection Syndrome (LARS) is a debilitating condition post-surgery, requiring long-term management. Aim: To evaluate the benefits of long-term transanal irrigation (TAI) treatment (up to 24 months) for LARS patients. Methods: A multicenter study across 13 centers included 159 patients to assess satisfaction with TAI for bowel control and quality of life (QoL). Secondary objectives included evaluating symptom improvement, dropout rates, and TAI characteristics (frequency, water volume, duration). Validated questionnaires were administered at baseline (T0) and after 1 (T1), 6 (T6), 12 (T12), and 24 (T24) months. Statistical analyses included signed rank sum tests for score differences, F-tests for symptom frequency, mixed-effects models for LARS category changes. Results: TAI significantly improved satisfaction and QoL (p < 0.001). At T0, 84.8 % of patients had major LARS, decreasing to 16.5 % at T24. Mean LARS score improved by 19.8 ± 12.3 points from baseline to T24, showing a sustained and significant long-term improvement (p < 0.001). Symptom frequency decreased from 4.3 events per patient at T0 to 0.5 at T24 (p < 0.001). Dropouts occurred in 5 (11.4 %) cases by T6, 9 (6.8 %) by T12, and 12 (8.9 %) by T24. Conclusion: This study confirmed for the first time that long-term TAI treatment benefits LARS patients by improving symptoms, satisfaction, and QoL, with effects sustained over 24 months.