Criteria for evaluation of the anticoagulant therapy efficacy: the role of «surrogate criteria»

Abstract

The article is devoted to the problem of using indirect indicators, or surrogate criteria, both in randomized clinical and observational studies. The reasons for the increasing frequency of using surrogate criteria in assessing the results of clinical trials are considered. The possible negative consequences of the widespread use of proxy measures and the need to educate clinicians to obtain evidence-based information using surrogate criteria rather than true clinical outcomes are discussed. Data from analyzes aimed at identifying the most important problems in the use of surrogate criteria in assessing the effectiveness of certain interventions are presented. The problem of using surrogate criteria in assessing the effectiveness and safety of the use of anticoagulants in patients with atrial fibrillation or venous thromboembolic complications is separately considered. The necessary conditions are provided to ensure the possibility of using surrogate criteria in studies assessing the effectiveness of interventions. Examples of the use of both justified and insufficiently justified use of surrogate criteria for assessing the effectiveness of anticoagulants in various clinical situations are considered. The results of a randomized clinical trial evaluating the effectiveness of an anticoagulant based on identifying surrogate criteria for atrial fibrillation using devices implanted in the heart are discussed. The problem of using surrogate criteria when assessing the risk of bleeding in studies assessing the effects of anticoagulants is discussed separately. The opinions of experts are presented, emphasizing the need for careful use of surrogate criteria when assessing the incidence of both venous thromboembolic complications and bleeding, since in such cases the results of comparing the benefits and risks of the intervention can be significantly distorted.

Keywords

• surrogate criteria
• atrial fibrillation
• venous thromboembolic events
• apixaban
• rivaroxaban
• warfarin.