LITHOTRIPSY VERSUS CHOLECYSTECTOMY FOR MANAGEMENT OF GALLSTONES - A DECISION-ANALYSIS BY MARKOV PROCESS

Extracorporeal shock-wave lithotripsy is a new treatment method that effectively disintegrates radiolucent gallstones and is associated with a low complication rate. Using the model of a Markov process for decision analysis, survival and costs under four possible strategies to treat gallstones were compared: expectant management with cholecystectomy (EC) or lithotripsy (EL) reserved for symptomatic gallstones; prophylactic cholecystectomy (PC) or lithotripsy (PL) for all gallstones. Life expectancy for the different strategies varies by few days. Only if high annual rates of pain and complication occurred in subjects with silent gallstones would both prophylactic procedures marginally increase life expectancy. Prophylactic cholecystectomy then would be more cost-effective than prophylactic lithotripsy. Expectant strategies remain much cheaper than prophylactic management over a broad range of probability values and procedural costs. Expectant use of lithotripsy costs less than cholecystectomy. A low success rate of lithotripsy would raise the direct costs of lithotripsy above those of cholecystectomy but leave total costs of both strategies in the same order of magnitude. Lithotripsy appears to be a feasible alternative to treat symptomatic but not asymptomatic gallstones.