A computer model for evaluating the costs of cholecystectomy or ursodiol treatment in the management of cholelithiasis.

Over 500,000 cholecystectomies are performed each year in the United States. The procedure has its risks (mortality is 1.2% in the general population and 3% in patients aged 75 years or over) and it is expensive: the average direct cost of each cholecystectomy is about $10,000, for a national total of $5 billion annually. An alternative to surgery is to dissolve the stone with ursodiol, a naturally occurring bile acid, which has been successfully used for cholesterol gallstones with a diameter less than 20 mm. A computer model was developed to compare the costs of surgery for gallstones and treatment with ursodiol. In a hypothetical health maintenance organization with one million enrollees, use of ursodiol treatment rather than cholecystectomy would result in cumulative savings of $8.5 million after one year, $30.7 million after five years, and $57.8 million after ten years.