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SAMe-TT2R2 Score in the Outpatient Anticoagulation Clinic to Predict Time in Therapeutic Range and Adverse Events
Fernando Pivatto Junior1, Rafael Selbach Scheffel1, Lucas Ries1
1Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS - Brazil.
Background:
The SAMe-TT2R2 score was developed to predict which patients on oral anticoagulation with vitamin K antagonists (VKAs) will reach an adequate time in therapeutic range (TTR) (> 65%-70%). Studies have reported a relationship between this score and the occurrence of adverse events.
Objective:
To describe the TTR according to the score, in addition to relating the score obtained with the occurrence of adverse events in patients with nonvalvular atrial fibrillation (AF) on oral anticoagulation with VKAs.
Methods:
Retrospective cohort study including patients with nonvalvular AF attending an outpatient anticoagulation clinic of a tertiary hospital. Visits to the outpatient clinic and emergency, as well as hospital admissions to the institution, during 2014 were evaluated. The TTR was calculated through the Rosendaal´s method.
Results:
We analyzed 263 patients (median TTR, 62.5%). The low-risk group (score 0-1) had a better median TTR as compared with the high-risk group (score ≥ 2): 69.2% vs. 56.3%, p = 0.002. Similarly, the percentage of patients with TTR ≥ 60%, 65% or 70% was higher in the low-risk group (p < 0.001, p = 0.001 and p = 0.003, respectively). The high-risk group had a higher percentage of adverse events (11.2% vs. 7.2%), although not significant (p = 0.369).
Conclusions:
The SAMe-TT2R2 score proved to be effective to predict patients with a better TTR, but was not associated with adverse events.
Fundamento:
O escore SAMe-TT2R2 foi desenvolvido visando predizer quais pacientes em anticoagulação oral com antagonistas da vitamina K (AVKs) atingirão um tempo na faixa terapêutica (TFT) adequado (> 65%-70%) no seguimento. Estudos também o relacionaram com a ocorrência de eventos adversos.
Objetivos:
Descrever o TFT de acordo com o escore, além de relacionar a pontuação obtida com a ocorrência de eventos adversos adversos em pacientes com fibrilação atrial (FA) não valvar em anticoagulação oral com AVKs.
MéTodos:
Estudo de coorte retrospectivo incluindo pacientes com FA não valvar em acompanhamento em ambulatório de anticoagulação de um hospital terciário. Foi realizada uma avaliação retrospectiva de consultas ambulatoriais, visitas a emergência e internações hospitalares na instituição no período de janeiro-dezembro/2014. O TFT foi calculado aplicando-se o método de Rosendaal.
Resultados:
Foram analisados 263 pacientes com TFT mediano de 62,5%. O grupo de baixo risco (0-1 ponto) obteve um TFT mediano maior em comparação com o grupo de alto risco (≥ 2 pontos): 69,2% vs. 56,3%, p = 0,002. Da mesma forma, o percentual de pacientes com TFT ≥ 60%, 65% ou 70% foi superior nos pacientes de baixo risco (p < 0,001, p = 0,001 e p = 0,003, respectivamente). Os pacientes de alto risco tiveram um percentual maior de eventos adversos (11,2% vs. 7,2%), embora não significativo (p = 0,369).
ConclusõEs:
O escore SAMe-TT2R2 foi uma ferramenta eficaz na predição do TFT em pacientes com FA em uso de AVKs para anticoagulação, porém não se associou à ocorrência de eventos adversos.
Insights
The SAMe-TT2R2 score effectively predicts time in therapeutic range (TTR) for patients on warfarin, identifying those likely to achieve optimal anticoagulation. However, the score did not significantly correlate with adverse events in this study.
Area of Science:
- Cardiology
- Pharmacology
- Clinical Medicine
Background:
- The SAMe-TT2R2 score was developed to predict adequate time in therapeutic range (TTR) in patients using vitamin K antagonists (VKAs).
- Previous studies suggest a link between the SAMe-TT2R2 score and adverse event occurrence.
Purpose of the Study:
- To assess the TTR based on the SAMe-TT2R2 score in patients with nonvalvular atrial fibrillation (AF) on VKAs.
- To determine the association between the SAMe-TT2R2 score and adverse events in this patient population.
Main Methods:
- A retrospective cohort study was conducted on 263 patients with nonvalvular AF receiving VKA therapy.
- Data on outpatient visits, emergency visits, and hospital admissions in 2014 were analyzed.
- Time in therapeutic range (TTR) was calculated using the Rosendaal method.
Main Results:
- Patients in the low-risk SAMe-TT2R2 score group (0-1) demonstrated a significantly higher median TTR (69.2%) compared to the high-risk group (≥2) (56.3%, p=0.002).
- A greater percentage of low-risk patients achieved TTR thresholds of 60%, 65%, and 70% compared to high-risk patients (p<0.001, p=0.001, p=0.003, respectively).
- While the high-risk group had a higher incidence of adverse events (11.2% vs. 7.2%), this difference was not statistically significant (p=0.369).
Conclusions:
- The SAMe-TT2R2 score is a valuable tool for predicting TTR in patients on VKAs, identifying individuals likely to maintain therapeutic anticoagulation.
- The study found no significant association between the SAMe-TT2R2 score and the occurrence of adverse events in patients with nonvalvular AF on VKAs.
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