A comparison of the CHARGE–AF and the CHA2DS2-VASc risk scores for prediction of atrial fibrillation in the Framingham Heart Study

Abstract

Background Atrial fibrillation (AF) affects more than 33 million individuals worldwide and increases risks of stroke, heart failure, and death. The CHARGE-AF risk score was developed to predict incident AF in three American cohorts and it was validated in two European cohorts. The CHA2DS2-VASc risk score was derived to predict risk of stroke, peripheral embolism, and pulmonary embolism in individuals with AF, but it has been increasingly used for AF risk prediction. We compared CHARGE-AF risk score versus CHA2DS2-VASc risk score for incident AF risk in a community-based cohort. Methods and Results We studied Framingham Heart Study participants aged 46 to 94 years without prevalent AF and with complete covariates. We predicted AF risk using Fine-Gray proportional sub-distribution hazards regression. We used the Wald χ2 statistic for model fit, C-statistic for discrimination, and Hosmer-Lemeshow (HL) χ2 statistic for calibration. We included 9722 observations (mean age 63.9 ± 10.6 years, 56% women) from 4548 unique individuals: 752 (16.5%) developed incident AF and 793 (17.4%) died. The mean CHARGE-AF score was 12.0 ± 1.2 and the sub-distribution hazard ratio (sHR) for AF per unit increment was 2.15 (95% CI, 99–131%; P < .0001). The mean CHA2DS2-VASc score was 2.0 ± 1.5 and the sHR for AF per unit increment was 1.43 (95% CI, 37%-51%; P < .0001). The CHARGE-AF model had better fit than CHA2DS2-VASc (Wald χ2 = 403 vs 209, both with 1 df), improved discrimination (C-statistic = 0.75, 95% CI, 0.73–0.76 vs C-statistic = 0.71, 95% CI, 0.69–0.73), and better calibration (HL χ2 = 5.6, P = .69 vs HL χ2 = 28.5, P < .0001). Conclusion The CHARGE-AF risk score performed better than the CHA2DS2-VASc risk score at predicting AF in a community-based cohort.

Heart rate and premature atrial contractions at 24hECG independently predict atrial fibrillation in a population-based study

“…AF is a major population health problem and improved AF prediction may be useful in attempts to construct primary prevention programme 20. This study has attempted to assess the relationship between heart rate and PACs, two known predictors of AF, as regards AF risk, in order to assess a plausible mechanistic link between the two and to determine whether these variables may be useful in AF prediction.…”

The appropriate use of risk scores in the prediction of atrial fibrillation

“…The results from Christophersen et al (19) are consistent with those from a recent publication from the MESA cohort (14). In the MESA analysis, which included a multi-ethnic sample of 6,663 adults in the United States without prior cardiovascular disease, the C-statistic for the CHARGE-AF score was 0.779 (95% CI, 0.744-0.814), compared with a C-statistic of 0.695 (95% CI, 0.654-0.735) for the CHA 2 DS 2 -VASc score.…”

“…A recent report published in the American Heart Journal aimed to directly compare the predictive ability and calibration of the CHARGE-AF and CHA 2 DS 2 -VASc risk scores for the prediction of incident AF (19). For this analysis, Christophersen et al used data from 4,548 (mean age, 63.9±10.6 years, 56% women) participants form the original FHS and Framingham Offspring Cohort applying a pooled-examination approach and standard statistical techniques (Wald χ 2 statistic to assess model fit, the C-statistic to assess model discrimination, and the Hosmer-Lemeshow (HL) χ 2 statistic to assess model calibration).…”

Validation of a genetic risk score for atrial fibrillation: A prospective multicenter cohort study

“…To this end, efforts have been made to predict the occurrence of AF using risk scores based on clinical factors associated with disease [ 13 , 14 ]. While clinical risk factors for AF (e.g., obesity, hypertension, and obstructive sleep apnea) are well established, risk scores incorporating these factors have fallen short in validation studies [ 15 ].…”