Does age impact outcomes of retrograde intrarenal surgery in the elderly? Results from 366 patients from the FLEXible ureteroscopy outcomes registry (FLEXOR)

Background: There has been a consistent increase in the last decades in prevalence of renal stones in elderly. Aims: To evaluate outcomes of retrograde intrarenal surgery (RIRS) for renal stones in elderly and factors associated with postoperative complications and residual fragments (RFs). Methods: Data from 12 centers were retrospectively reviewed. Inclusion criteria: ≥ 75 years, renal stones only, normal renal anatomy. Patients were divided into three groups; Group 1: patients aged 75–79 years; Group 2: age 80–84 years; Group 3: age ≥ 85 years. Multivariable logistic regression analyses were performed to assess factors associated with perioperative complications, sepsis, and RFs. Results: 366 patients were included. There were 189 patients in Group 1, 113 in Group 2, and 64 in Group 3. There was no difference between groups regarding stone features and total surgical time. Median length of stay was significantly longer in Group 3 (6.0 days, vs 2.0 days in Group 2 vs 2.5 days in Group 1, p = 0.043). There was no significant difference in postoperative complications and RFs between the groups. At multivariable logistic regression analysis, female gender (OR 2.82) and maximum stone diameter (OR 1.14) were associated with higher odds of sepsis, while surgical time (OR 1.12) and the use of a reusable ureteroscope (OR 6.51) with overall complications. Stone size (OR 1.23) was associated with higher odds of RFs. Conclusion: RIRS showed safety and efficacy for kidney stones in elderly patients. Surgical time should be kept as short as possible to avoid higher odds of postoperative complications, particularly in females.