Use of CHADS₂ and CHA₂DS₂-VASc scores to predict subsequent myocardial infarction, stroke, and death in patients with acute coronary syndrome: data from Taiwan acute coronary syndrome full spectrum registry

Abstract

Background: Acute coronary syndrome (ACS) patients have a wide spectrum of risks for subsequent cardiovascular events and death. However, there is no simple, convenience scoring system to identify risk of adverse outcomes. We investigated whether CHADS₂ and CHA₂DS₂-VASc scores were useful tools to assess the risk for adverse events among ACS patients.

Methods: This observational prospective study was conducted at 39 hospitals. Totally 3,183 patients with ACS were enrolled, and CHADS₂ and CHA₂DS₂-VASc scores were calculated. The primary endpoint was occurrence of adverse event, including subsequent myocardial infarction, stroke, or death, within 1 year of discharge.

Results: CHADS₂ and CHA₂DS₂-VASc scores were significant predictors of adverse events in separate multivariate regression analyses. A Kaplan-Meier analysis of CHADS₂ and CHA₂DS₂-VASc scores of ≥2 showed a higher rate of adverse events as compared with scores of <2 (P<0.001;log-rank test). CHA₂DS₂-VASc score was better than CHADS₂ score in predicting subsequent adverse events; the area under the receiver operating characteristic curve increased from 0.66 to 0.70 (p<0.001). Patients with CHADS₂ scores of 0 or 1 were further classified according to CHA₂DS₂-VASc score, using a cutoff value of 2. The rate of adverse events significantly differed between those with a score of <2 and those with a score of ≥2 (4.1% vs.10.7%, P<0.001).

Conclusions: CHADS₂ and CHA₂DS₂-VASc scores were useful predictors of subsequent adverse events in ACS patients.

Conflict of interest statement

Competing Interests: Although this research is partly sponsored by Sanofi-Aventis company, the data is independently analyzed by the investigators. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials. The authors declare no conflict of interest.

Figures

Figure 1. Rates of adverse events, including myocardial infarction (MI), stroke, or death, according to CHADS2 and CHA2DS2-VASc scores.

The rate of MI, stroke, or death increased as CHADS2 (A) and CHA2DS2-VASc (B) scores increased.

Figure 2. Adjusted hazard ratios for the composite endpoint myocardial infarction (MI), stroke, or death, in relation to CHADS2 or CHA2DS2-VASc scores, in patients with acute coronary syndrome.

The risk of MI, stroke, or death progressively increased with each unit increase in CHADS2 and CHA2DS2-VASc scores. The reference groups are patients with scores of 0. * And § are defined as p<0.001 vs. CHADS2 and CHA2DS2-VASc scores of 0, respectively.

Figure 3. Kaplan-Meier curves for the time to the composite endpoint of myocardial infarction (MI), stroke, or death, according to CHADS2 and CHA2DS2-VASc scores.

Survival analysis showed that a CHADS2 score of ≥2 was associated with a higher event rate than a score of <2 (p<0.001; log-rank test) (A). In addition, a CHA2DS2-VASc score of ≥2 was a significant predictor of adverse events (p<0.001; log-rank test) (B).

Figure 4. Receiver operating characteristic (ROC) curves for CHADS2, CHA2DS2-VASc and GRACE scores predicting myocardial infarction (MI), stroke, or death.

Diagnostic performance in predicting MI, stroke, or death was better for CHA2DS2-VASc score than for CHADS2 score. The area under the ROC curve (AUC) increased from 0.66 to 0.70, and the difference was statistically significant (p<0.001). Besides, the diagnostic accuracy in predicting adverse events was better for GRACE score than for CHA2DS2-VASc score (AUC 0.74 vs. 0.70, p<0.001).

Figure 5. Flowchart of adverse event rates and risk scores in the patients with CHADS2 score of 0 or 1.

(A) Rate of MI, stroke, or death in patients with a CHADS2 score of 0 or 1, according to CHA2DS2-VASc score. The rate of myocardial infarction (MI), stroke, or death progressively increased, from 3.0% to 33.3%, with increasing CHA2DS2-VASc score. (B) The flowchart shows the rate of MI, stroke, or death in patients stratified by CHADS2 and CHA2DS2-VASc scores.