Is extracorporeal shock wave lithotripsy the preferred treatment option for elderly patients with urinary stone? A multivariate analysis of the effect of patient age on treatment outcome.

Abstract

To investigate the effect of patient age on the stone-free rate (SFR) in patients with urinary calculi treated by extracorporeal shockwave lithotripsy (ESWL). In all, 2192 solitary radio-opaque urinary stones of 5-15 mm were identified in adult patients receiving primary ESWL. Patients were divided into three age groups, i.e. < or = 40, 41-60 and >60 years (579, 1026 and 587 patients, respectively). Multiple logistic regression was used to assess the effect of age and other possible predicting factors (gender, stone characteristics, e.g. side, site and size, and the type of lithotripter used) on the SFR at 3 months after treatment. The overall adjusted odds ratios (95% confidence interval) for the SFR for those aged 41-60 and >60 years (taking those aged < or= 40 years as the reference) were 0.708 (0.573-0.875; P = 0.001) and 0.643 (0.506-0.818; P < 0.001). However, if the patients were divided into those with renal or ureteric stones, only the SFR of the former was affected by age, and the adjusted odds ratios were 0.665 (0.512-0.864; P = 0.002) and 0.629 (0.470-0.841; P = 0.002), respectively. Ageing had no effect on the SFR for ureteric stones. The SFR after ESWL for renal stones, but not ureteric stones, was significantly lower in older patients. Further studies on the effects of ageing on renal stone clearance after ESWL are needed to improve stone management in the elderly population.