Chemoprophylaxis of prosthetic joint patients during dental treatment: a decision-utility analysis.

A decision-analytic model and a cost effectiveness analysis was performed on 1 million hypothetic prosthetic joint patients undergoing dental treatment, to determine the most cost-effective strategy to prevent late prosthetic joint infections. The cost per quality-adjusted life-year saved (QALY) was determined for three preventive strategies: no prophylaxis, oral penicillin, and oral cephalexin. The UCLA Pain-Walking-Function-Activity Scale was used to obtain quality-of-life adjustments (utility assessment) for the study population. Costs were derived from 70 patients hospitalized between July 1, 1982, and June 30, 1986, at the UCLA Center for Health Sciences. The most cost-effective preventive strategy was the no prophylaxis alternative ($196,500/QALY). However, by recommending a 1-day strategy of oral cephalexin only to those dental patients at high risk for late prosthetic joint infections rather than a 3-day regimen to all patients, the cost effectiveness improved from $1.1 million/QALY to $446,100/QALY while maintaining a low risk of death (0.38 deaths per 10(6) dental visits).