Utilidad marginal de la escala SAMe-TT2R2 en la predicción de la calidad de la anticoagulación oral con acenocumarol en el “mundo real”

Abstract

IntroductionThe SAMe-TT2R2 score has been proposed to predict the quality of anticoagulation with vitamin K antagonists. ObjectiveTo validate the discriminatory power of the SAMe-TT2R2 score real-life in a patient cohort with non-valvular atrial fibrillation. Material and methodsAn observational study was conducted on patients with non-valvular atrial fibrillation treated with vitamin K antagonists for at least six months. Good anticoagulation control was considered a time in the therapeutic range of ≥ 65%, estimated with the Rosendaal method. The relationship between the SAMe-TT2R2 score and the anticoagulation control was evaluated using a binary logistic regression. The discriminatory power was determined using the calculation of the value of the area under the ROC curve. ResultsThe study included total of 241 patients, with a mean age of 78.6±8.6 years, and 53% women. The mean time in the therapeutic range was 59.4±25.4%, low according to the increase in the SAMe-TT2R2 score. In general, the scale did not appear to have the power to discriminate patients with adequate anticoagulation control, with an area under the ROC curve of 0.57 (95% CI: 0.49-0.64, P=.06). It was only useful for extreme scores, with a probability of good control of 65.1% vs. 34.9%, P=.01 for a value of 0, and of 0% vs. 100%, P=.03 for ≥ 4. The disparity ratio of having a time in the therapeutic range of <65% for a score ≥2 was 1.22 (95% CI: 0.73-2.02, P=.44). ConclusionIn a cohort of patients with non-valvular atrial fibrillation and with real-life data, the SAMe-TT2R2 scale, did not, on the whole, show discriminatory power for the adequate control of anticoagulation with vitamin K antagonists. It only showed to be useful to correctly classify the cases with extreme scores.