Surgical outcomes in elective sigmoid resection for diverticulitis stratified according to indication: a propensity-score matched cohort study with 903 patients

OBJECTIVE: Weighing the perioperative risk of elective sigmoidectomy is done regardless of the specific diverticulitis classification. The aim of this study is to evaluate surgical outcomes according to the classification grade and the indication. METHODS: All patients who underwent elective colonic resection for diverticulitis during the ten-year study period were included. They were divided into two groups: relative surgery indication (RSI) and absolute surgery indication (ASI). RSI included microabscess and recurrent uncomplicated disease. ASI included macroabscess and recurrent complicated disease. Propensity score-matching (PSM, 1:1) was performed. RESULTS: 585 patients fulfilled criteria for RSI and 318 patients fulfilled criteria for ASI. In the univariate analysis, RSI patients were younger (62 vs. 67.7 years, p < 0.001), had a higher physical status (ASA score 1 or 2 in 80.7% vs. 60.8%, p < 0.001), were less immunosuppressed (3.4% vs. 6.9%, p = 0.021) and suffered less often from coronary heart disease (3.8% vs. 7.2%, p = 0.025). After PSM, 318 RSI vs. 318 ASI patients were selected; baseline characteristics results were comparable. The proportion of planned laparoscopic resection was 93% in RSI versus 75% in ASI (p < 0.001), and the conversion rate to open surgery for laparoscopic resection was 5.0% and 13.8% in RSI versus ASI, respectively (p < 0.001). Major morbidity (Clavien/Dindo ≥ IIIb) occurred less frequently in RSI (3.77% vs. 10%, p = 0.003). A defunctioning stoma was formed in 0.9% and 11.0% in RSI vs ASI, respectively (p < 0.001). CONCLUSION: The lower risk for postoperative morbidity, the higher chance for a laparoscopic resection and the decreased rate of stoma formation are attributed to patients with recurrent uncomplicated diverticulitis or diverticulitis including a microabscess as compared to patients with complicated diverticulitis or diverticulitis and a macroabscess, and this applies even after PSM.