Patient decision making for asymptomatic renal calculi: balancing benefit and risk

To evaluate which variables affect patients' decisions on the management of asymptomatic renal calculi.

We hypothesized that patients who had experienced greater pain, passed larger or more stones, or passed stones more recently would be more likely to choose surgical intervention (ureteroscopy [URS] or shock wave lithotripsy [ESWL]) instead of observation (OBS). The survey was distributed to 101 patients in our stone clinic. The patients were given a hypothetical scenario of an asymptomatic 8-mm lower pole stone and descriptions for OBS (annual radiography, 40% chance of growth >10 mm within 4 years, 20% chance of passage), ESWL (65% success rate), and URS (90% success rate, with stent placement for 1 week). The patients were also asked whether they would rather defer the decision to their physician.

Of the patients, 22.8% chose OBS, 29.7% chose URS, and 47.5% chose ESWL. The patients who had passed larger stones (P = .029) were less likely to choose OBS over surgery. Of the 78 patients who chose intervention, 61.5% preferred ESWL. The patients were more likely to choose URS if they had previously undergone URS (P = .0064) and stent placement (P = .048), and the patients were more likely to choose ESWL if they had a previously undergone ESWL (P = .019). Surgical choice was not affect by size of the largest stone passed (P = .46), date of last passage (P = .080), previous pain intensity (P = .11), previous percutaneous nephrolithotomy (P = .73), or number of stones passed (P = .51). Finally, 56.4% of patients deferred the decision of the treatment approach to the physician.

Previous stone experience and treatment significantly affected treatment choice. Patients rely on their physician to educate them on the alternatives and play an active role in selecting the treatment approach.