Comparison of safety and outcomes of shock wave lithotripsy between elderly and non-elderly patients

Background: This study compared the clinical outcomes of extracorporeal shock wave lithotripsy between elderly (aged ≥65 years) and non-elderly (aged <65 years) patients. Methods: A retrospective review of medical records was performed on 483 (non-elderly: 245, elderly: 238) patients with upper urinary tract stones who underwent shock wave lithotripsy between 2007 and 2015. The demographic data, stone parameters, stone-free rate, retreatment rate, and complication rate were analyzed in both elderly and non-elderly patient groups. Results: There was no significant difference between non-elderly and elderly patients in terms of stone-free rate (46.5% vs 41.1%, P>0.05) regardless of stone site or stone size and overall retreatment rate (41.6% vs 37.0%, P>0.05). Elderly patients had a higher complication rate than non-elderly patients (15.5% vs 23.5%, P=0.026). The most common complication was flank pain. Receiver operating characteristic curves predicted that elderly patients (cutoff value: 65 years of age) had a higher risk of complications and that patients with smaller stones (cutoff value: 0.8 cm) had a higher stone-free rate. Conclusion: This study showed that elderly patients with upper urinary tract stones undergoing shock wave lithotripsy had comparable efficacy for stone-free rates and retreatment rates, but higher complication rates.