Dynamic evaluation of metabolic syndrome and its impact on surgical outcomes after Retrograde Intrarenal Surgery (RIRS): an academic single-center retrospective study

Purpose To evaluate their impact on surgical outcomes, such as stone-free rate, consequent need for a second surgery and perioperative complications in patients submitted to RIRS. Patients and Methods A single-center retrospective study including adult patients undergoing RIRS. Exclusion criteria were abnormal urinary tract anatomy, bilateral or concomitant ureteral stone surgery. Clinical and surgical characteristics were collected. Stone free status was defined as no clinically relevant residual fragments (> 2mm) at 3-months after surgery. Group comparison and logistic regression were studied to assess predictors and surgical outcomes Results 120 patients (63 men and 57 women) who underwent RIRS were included. Mean age was 54.0 (± 13.2). 37 (30.8%) cases were classified as FMD, 49 (40.9%) as MMD and 34 (28.3%) as MetS. Stone free (SF+) rate in the general population was 55.8% and 64.9%, 57.1%, 44.1% in FMD, MMD and Mets patients, respectively. Patients no stone free (SF-) presented a higher prevalence of diabetes in comparison to SF + cases (p = 0.002). Patients who needed a second procedure (40%) to eliminate residual ureteral fragments presented a higher prevalence of diabetes (58.3% vs. 30.6%,p = 0.005) and hypertriglyceridemia (41.7% vs. 20.8%, p = 0.024). At univariate analysis diabetes resulted to be a significant predictor of no stone free status at 3 months (OR 3.56, 95% C.I. 1.681–7.757, p-value = 0.001) and for the need of second surgery (OR 3.182, 95% C.I. 1.500–6.919,p-value = 0.003). Conclusion Diabetes appears to be a significant risk factor for poor outcomes after RIRS. Our results may be relevant during patient counselling and surgery planning.