IJCS | Volume 31, Nº4, July / August 2018

DOI: 10.5935/2359-4802.20180028 383 ORIGINAL ARTICLE International Journal of Cardiovascular Sciences. 2018;31(4)383-392 Mailing Address: Sérgio Henrique Simonetti Rua das Tâmaras, 210. Postal Code: 04361-130, Vila Paulista, São Paulo, SP - Brazil. E-mail: shs.nurse04@gmail.com , sergioh@dantepazzanese.org.br Adherence Score for Users of Oral Anticoagulants Sérgio Henrique Simonetti, 1 Ana Cristina Mancussi e Faro, 2 Estela Regina Ferraz Bianchi 2 Instituto Dante Pazzanese de Cardiologia, 1 São Paulo - Brazil Escola de Enfermagem da Universidade de São Paulo, 2 São Paulo - Brazil Manuscript received June 05, 2017, revised manuscript December 21, 2017, accepted January 15, 2018. Abstract Background: The score is an effective instrument for the assessment of treatment adherence in users of oral anticoagulants and maintenance of INR (international normalized ratio) within the therapeutic range. Objective: To develop an adherence score for oral anticoagulant users for the maintenance of INR within the therapeutic range. Methods: This was an analytical, observational, cross-sectional study, with a quantitative approach, conducted in a public cardiology hospital. A total of 607 patients who met the inclusion criteria were evaluated. Variables with a significance level of 5% in the exploratory analysis and considered clinically relevant were included and subjected to a multiple logistic regression model. Predictive accuracy of the model was determined using the C statistic. Results: The variables with a significance level of 5% in the multivariate analysis were: education, family income, inadequate use of medications, drug-drug interactions, invasive procedures, food-drug interactions, physical activity, medical conditions, other factors, and complications related to oral anticoagulant therapy. The following prognostic variables were identified: family income, inadequate use of medications, invasive procedures, drug- drug interactions, dietary habits, medical conditions, other factors (stress, thinness, weight loss). C-statistic for adherence score was 0.94. Conclusion: The Simonetti adherence score proved to be easily applicable and feasible, with high predictive value for influencing factors, promoting the improvement of adherence and maintenance of INR in the ideal range. (Int J Cardiovasc Sci. 2018;31(4)383-392) Keywords: Cardiovascular Diseases; Anticoagulants/therapy; Probability; Medication Adherence; Health Education. Introduction Health promotion is a key strategy for prevention of thromboembolic events in patients on oral anticoagulant therapy (OAC-T) in addition to other aspects related to the assistance of this population. In this context, health professionals, nurses and physicians play the role of educators, particularly in providing clear guidance on risk factors and possible signs and symptoms and related complications associated with a OAC-T. 1 Stability of OAC-T is associated with treatment adherence, in addition to other factors including age, concomitant use of other drugs, comorbidities, irregular use of vitamin K, inadequate use of the drug, and hereditary polymorphism. 2 Educational programs for outpatient management of patients on OAC-T have been crucial for the approach of drug and dietary interactions with coumarin derivatives, which may affect treatment adherence. 2,3 A study 4 pointed out important considerations about adherence to OAC-T. First, knowledge about adherence to OAC-T is still a challenge among health professionals in national and international contexts. Second, the study provides data on instruments proposed by health professionals aimed at improving patients’ adherence and knowledge about the treatment, and on patients’ sociodemographic status. The authors also reported the scarcity of studies on factors that may influence therapy