The Sex, Age, Medical History, Treatment, Tobacco Use, Race Risk (SAMe TT2R2) Score Predicts Warfarin Control in a Singaporean Population.
BACKGROUND
Warfarin reduces stroke risk in atrial fibrillation (AF) patients but requires ongoing monitoring. Time in therapeutic range (TTR) is used as a measure of warfarin control, with a TTR less than 60% associated with adverse patient outcomes. The Sex, Age, Medical history, Treatment, Tobacco use, Race (SAMe-TT2R2) score has been identified as a model able to predict warfarin control, but this has been tested in mainly Caucasian populations. Therefore, the aim of this study was to determine the ability of the SAMe-TT2R2score to predict warfarin control in a Singaporean population consisting of Chinese, Malay, and Indian race.


METHODS
Retrospective data were collected from the National Heart Centre Singapore for AF patients receiving warfarin between January and June 2014. The TTR and the SAMe-TT2R2score were calculated for each patient.


RESULTS
The 1137 non-valvular AF patients had a mean TTR of 58.0 ± 34.3% and a median SAMe-TT2R2score of 3. The categorized SAMe-TT2R2scores (2 versus >2) showed a significant reduction in mean TTR for the entire population (63.2% versus 55.8%, P = .0004) and also when categorized according to race for Chinese (62.7% versus 56.9%, P = .0075) and Malay (68.4% versus 50.6%, P = .0131) populations.


CONCLUSIONS
The SAMe-TT2R2tool is effective in predicting warfarin control in a Singaporean population as patients with a score greater than 2 had poor control. The minimum score for non-Caucasian patients is 2; thus, in these patients, the presence of any additional risk factors identified in the SAMe-TT2R2tool categorizes them as unlikely to achieve adequate warfarin control and possible candidates for alternative anticoagulants.
Menzies Health Institute Queensland, Griffith University, Queensland, Australia; School of Pharmacy, Griffith University, Queensland, Australia.
Nijole
N
Bernaitis
Cardiology Department, National Heart Centre Singapore, Singapore.
Chi Keong
CK
Ching
Pharmacy Department, National Heart Centre Singapore, Singapore.
Liping
L
Chen
Pharmacy Department, National Heart Centre Singapore, Singapore.
Jin Shing
JS
Hon
Pharmacy Department, National Heart Centre Singapore, Singapore.
Siew Chong
SC
Teo
Menzies Health Institute Queensland, Griffith University, Queensland, Australia; School of Pharmacy, Griffith University, Queensland, Australia.
Andrew K
AK
Davey
Menzies Health Institute Queensland, Griffith University, Queensland, Australia; School of Pharmacy, Griffith University, Queensland, Australia. Electronic address: s.dukie@griffith.edu.au.
Shailendra
S
Anoopkumar-Dukie
D000367:Age Factors; D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000188:drug therapy / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D044469:Racial Groups; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors; D012846:Singapore / Q000453:epidemiology; D020521:Stroke / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D064424:Tobacco Use / Q000453:epidemiology*; D014859:Warfarin / Q000627:therapeutic use*
D000925:Anticoagulants; D014859:Warfarin
Warfarin; anticoagulant; atrial fibrillation; predictor model