Incidence and risk factors of low anterior resection syndrome after sphincter-preserving radical resection for low rectal cancer

BACKGROUNDLow anterior resection syndrome (LARS) represents one of the most prevalent and debilitating complications following sphincter-preserving surgery for rectal cancer (RC), severely impairing the quality of life of patients with low RC.Early identification of patients at high risk of long-term major LARS is essential for improving postoperative patient outcomes. AIMTo determine the incidence of, and potential risk factors for, long-term major LARS after sphincter-preserving resection for RC. METHODSThe Medline, Web of Science, EMBASE, and Cochrane Library databases were searched from their inception to January 2026.Concurrently, patients who underwent sphincter-preserving surgery for RC at our centre between 2019 and 2021 were retrospectively analysed to explore the incidence and risk factors for major LARS after surgery, and a meta-analysis was performed. RESULTSIn total, 2685 studies were retrieved, of which 20 observational studies were included in the meta-analysis.Meanwhile, 174 patients with RC from our centre were reviewed and followed up; consequently, 6380 patients were included in the final meta-analysis.The results of the meta-analysis demonstrated that the incidence of long-term major LARS was 35% (95%CI: 29%-41%, I² = 96%).Risk factors identified included distance from the anal verge (weighted mean difference = -1.52,P < 0.001), particularly when ≤ 5 cm [odds ratio (OR) = 2.51, P < 0.001], neoadjuvant therapy (OR = 3.01, P < 0.001), adjuvant radiotherapy and adjuvant chemotherapy (OR = 2.38, P = 0.001 and OR = 1.41,P < 0.001, respectively), protective stoma (OR = 2.65, P < 0.001), intersphincteric resection (OR = 3.32, P < 0.001) and anastomotic leakage (OR = 2.92, P < 0.001).Age, sex, body mass index, and lymphatic metastasis were not associated with major LARS. CONCLUSIONWe identify seven potential risk factors for long-term major LARS in patients with RC.These findings support early identification of high-risk patients and a wholecourse nursing-management model.