Abstract
Background
Previous trials have shown that the C-statistics of SAMe-TT2R2 score in the prediction of suboptimal time in therapeutic range (TTR) is very low.
Objectives
To propose the novel risk score model for predicting the poor anticoagulation control in atrial fibrillation (AF) patients compared with the SAMe-TT2R2 score.
Methods
We prospectively recruited AF patients from 27 hospitals between 2014 and 2017 in the COOL AF Thailand registry. The poor anticoagulation control was defined as TTR <65%. Multivariate logistic regression analysis was performed for the prediction of poor anticoagulation control. The novel risk score model was then generated. Receiver operating characteristic (ROC) curve analysis was performed to calculate the C-statistics and to compare between the novel risk score model and the SAMe-TT2R2 score. Net Reclassification Index (NRI) and Integrated Discrimination Index (IDI) were performed.
Results
Of 3,461 patients, 2,233 patients taking warfarin having available TTR data were retrieved. There were 1,432 patients having poor anticoagulation control (TTR < 65%) and 801 patients having good anticoagulation control (TTR ≥ 65%). Symptomatic AF, diabetes, heart failure, and a history of bleeding were associated with increased risk while obesity, AF duration, and paroxysmal AF were associated with decreased risk of poor anticoagulation control. SHOB-D2AF score was created. The C-statistics of SHOB-D2AF score was greater than the SAMe-TT2R2 score (0.584 vs 0.506, P < 0.001). NRI of the SHOB-D2AF score was 17.82% compared with the SAMe-TT2R2 score.
Conclusions
SHOB-D2AF score was the novel risk score which was better than the SAMe-TT2R2 score in predicting poor anticoagulation control.