Significance of age on prognosis in patients treated by extracorporeal shock wave lithotripsy

PURPOSE: To investigate the effect of patient age on the stone-free rate (SFR) in patients with urinary stones treated by extracorporeal shock wave lithotripsy (ESWL). PATIENTS AND METHOD: 138 patients with renal calculi and 463 patients with ureteral calculi were treated using the Siemens Lithostar Multiline. Multiple logistic regression was used to investigate the effect of age and other possible predicting factors, i.e., gender, location, size, side, grade of hydronephrosis, symptom at onset and history of urolithiasis, on the SFR at 3 months after treatment. RESULTS: The overall SFR was 77.2%. The SFRs of aged< = 39, 40-49, 50-59, 60-69 and 70 = < years were 87.4%, 84.4%, 75.0%, 71.1% and 66.3%, respectively. The elder patients complained less frequency of pain at onset and showed more frequency of hydronephrosis. Multiple logistic regression analysis revealed that patient age (younger) as well as stone location (middle and distal ureter), size (small), hydronephrosis (mild or less) and symptom (painful) at onset were a independent (better) prognostic factors determining stone clearance after ESWL of upper urinary tract stones. CONCLUSION: The SFR of elder patients showed lower than that of younger ones, however, the former less needed analgesia for ESWL session than the latter. ESWL is convenient, relatively useful for elder patients.