Abstract 14953: Age Criteria Modification of Current Risk Scores Predicting Stroke in Patients With Atrial Fibrillation: A Nationwide Cohort Study From Korea
Background: Recently, it was suggested that lowering the age threshold for stroke risk estimation help identify truly low stroke risk in Taiwan atrial fibrillation (AF) patients.
Purpose: This study hypothesized that lowering the cutoff age in current risk stratification scores (CHA2DS2-VASc, CHADS2, and R2CHADS2) might provide better stroke prediction.
Methods: We included non-valvular AF patients not using oral anticoagulants (OACs) from 506,805 adults in prospective cohort data collected by the National Health Insurance Service in Korea. The younger age groups of the current risk scores were divided into 2 subgroups by a cutoff of 55 years. We assigned -1 point to the younger subgroup (<55 years of age) and did not change the points assigned to other groups. The modified risk scores were compared with each original score by calculating the c-statistics and net reclassification improvement (NRI).
Results: During 14,430 person-years of follow-up, we observed 188 ischemic strokes. Annualized stroke rate was 1.3%. C-statistics for the full point scores improved after modifying the age criteria in all the risk scores (CHA2DS2-VASc: from 0.74 to 0.75; CHADS2: from 0.74 to 0.76; R2CHADS2: from 0.74 to 0.75). In the primary prevention subset (3,286 patients with no history of prior stroke), there were similar improvements of c-statistics (CHA2DS2-VASc: from 0.68 to 0.70; CHADS2: from 0.67 to 0.70; R2CHADS2: from 0.67 to 0.70). The NRIs were positive comparing the modified score with each original score (CHA2DS2-VASc: 27.1%; CHADS2: 4.7%; R2CHADS2: 2.2%).
Conclusions: By using the lowered cutoff age (55 years of age), refining the age criteria of current risk scores provided improved stroke prediction in atrial fibrillation patients.
Author Disclosures: D. Kim: None. P. Yang: None. T. Kim: None. J. Uhm: None. H. Pak: None. M. Lee: None. B. Joung: None.
- © 2016 by American Heart Association, Inc.