AN OVERVIEW OF THE EFFECT OF COMPUTER-ASSISTED MANAGEMENT OF ANTICOAGULANT-THERAPY ON THE QUALITY OF ANTICOAGULATION

Risks and benefits of anticoagulant therapy depend directly of the dua lity of anticoagulation. We carried out a meta-analysis of published r andomized trials to assess the overall effectiveness of computer-assis ted prescription systems on the quality of anticoagulation. Randomized controlled trials were identified through electronic searches of the Medline database (1966-1997) and systematic analyses of the references of articles. Two investigators selected relevant papers and summarize d data from the studies. The outcome variable was the proportion of da ys within the target range of anticoagulation. A pooled estimate of th e common odds ratio of being in the target range and its confidence in terval was obtained by the Mantel-Haenszel method. Nine trials having included 1336 patients were identified. Computer systems were based on a pharmacokinetic-pharmacodynamic model and a bayesian prediction met hod, Most of them concerned the oral anticoagulant warfarin. The globa l odds ratio of being in the target range was 1.29 [95% Cl: 1.17-1.49] , thus meaning that the use of a computer for anticoagulation optimiza tion increased by 29% the proportion of visits where patients were app ropriately treated. The proportion of clinical events was too low for allowing a summary analysis, but major hemorrhages tended to be less f requent among patients of the computer groups than among patients of t he control groups (2.0 versus 3.9%). Evidence from randomized controll ed trials supports the effectiveness of computer-aided;anticoagulant p rescription. Widespread use of these systems in ambulatory care could increase the benefit/risk ratio of anticoagulant treatment at a low co st. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.