RESUMO
INTRODUCTION: Despite the increasing utilization of direct oral anticoagulant (DOAC) prescriptions, vitamin K antagonists (VKAs) remain the treatment of choice for treating and preventing thromboembolic events. The morbidity and mortality of VKAs are partly due to the difficulty of keeping the patient within the therapeutic range. For patients treated by VKA, time in therapeutic range (TTR) is a quality parameter of treatment, widely used in clinical trials but rarely by prescribers. It is well established that its use correlates with the risk of hemorrhage, thrombosis or mortality. We studied this parameter in a cohort of patients to evaluate the quality of their therapeutic follow-up and tried to identify risk factors for low TTR. METHODS: The study was made in collaboration with LaboSud Oc Biologie for a duration of 4 months. It included 3387 patients representing 2,4029 INR. We calculated the patients' TTR. The laboratory transmitted to us the sex and age of each patient and the VKA molecule used, the therapeutic range and the specialty of the prescriber. We then analyzed the odds ratio associated with these different factors. RESULTS: The mean TTR was 68%, close to the TTR recommended by scientific societies. Patient's sex was the only statistically correlated factor, with a worse equilibrium in females taking VKAs (OR=1.22, 95% CI: 1.06-1.39, P=0.00552). Many factors usually correlated with poor equilibrium under VKA have not been studied due to lack of information. CONCLUSION: Given the context of economic restriction and the TTR of our cohort close to the recommended 70%, there would be no benefit in terms of safety to prefer DOAC for the patients involved in this study. Regular monitoring of the individual patient's as well as the cohort's TTR should optimize the management of patients receiving VKAs.
