Derivation,Validation And Application Of A Risk Assessment Model For Incident Atrial Fibrillation

Background and Objectives The incidence of atrial fibrillation(AF)is increasing,conferring a major healthcare issue in Asia.No risk score for assessing individuals’ risk of developing incident AF has been specifically developed for Asian subjects.Our aim was to investigate risk factors for incident AF in Asian subjects and to combine them into a simple clinical risk score.Material and Methods Risk factors for incident AF were analyzed in 471,446 subjects form the Chinese Yunnan Insurance Database(interval derivation cohort)and then combined into a simple clinical risk score.Internal validation was conducted by bootstrap analysis.External application of the new score was performed in 451,199 subjects from the Korean National Health Insurance Service(NHIS,external cohort).Results In the internal cohort,structural heart disease(SHD),heart failure(HF),age>75 years,coronary artery disease(CAD),hyperthyroidism,chronic obstructive pulmonary disease(COPD),and hypertension were independently associated with incident AF.Given the low prevalence and the extreme strong association of SHD with incident AF(hazard ratio,26.07;95%confidence interval[CI],18.22-37.30;P<0.001),these patients should be independently considered as high risk for AF and were excluded from the analysis.The remaining predictors were combined into the new simple C2HEST score:C2:CAD/COPD(1 point each);H:hypertension(1 point);E:elderly(age≥75 years,2 points);S:systolic HF(2 points);and T:thyroid disease(hyperthyroidism,1 point).The C2HEST score showed good discrimination with the area under the curve(AUC)of 0.75(95%CI,0.73-0.77)and had good calibration(P=0.774).The score was internally validated by bootstrap sampling procedure,giving an AUC of o.75(95%CI,0.73-0.77).External application gave an AUC of 0.65(95%CI,0.65-0.66).The C2HEST score was superior to CHADS2 and CHA2DS2-VASc score in both cohorts in predicting incident AF.Conclusions We have developed and validated the C2HEST score as a simple clinical tool to assess the individual risk of developing AF in the Asian population without SHD.Background and Objectives The C2HEST score was initially proposed for predicting incident atrial fibrillation(AF)in general population.Its performance in post-stroke subjects remains to be established,especially since subjects at high risk for incident AF should be targeted for more comprehensive screening.The present study aimed to evaluate this newly-established incident AF prediction risk score in a post-stroke population.Material and Methods This validation was based on a hospital-based nationwide cohort with 240,459 French post-stroke subjects.Kaplan-Meier curves for incident rate of AF were drawn to depict differences between varying risk categories.Discrimination of the C2 HEST score was evaluated using C-index,net reclassification index(NRI),integrated discriminatory improvement(IDI)and decision curve analysis(DCA).Results During 7.9±11.5 months of follow-up,14,095 subjects developed incident AF.The incidence of AF increased from 23.5 per 1,000 patient-years in patients with C2 HEST score 0 to 196.8 per 1,000 patient-years in patients with C2 HEST score >6.Kaplan-Meier curves showed a clear difference among different risk strata(log-rank P<0.0001).The C2 HEST score had good discrimination with C-index 0.734(95%confidence interval [Cl],0.732-0.736),which was better than the Framingham and CHA2DS2-VASC scores(P <0.0001,respectively).The C2 HEST score also showed superiority compared with the Framingham and CHA2DS2-VASC scores as was shown by NRI,IDI(P <0.0001,respectively)and DCA.Conclusions The C2 HEST score performed well in discriminating the individual risk of developing incident AF in a white European population hospitalized with previous stroke.This simple score may potentially be used as a risk stratification tool for decision-making in relation to a screening strategy for AF in post-stroke subjects.Background and Objectives Atrial high-rate episode(AHRE)is commonly seen in patients with cardiac electronic devices(CIED),which is associated with increased risk of thromboembolism.The present study aimed at evaluating the capacity of the C2 HEST score in predicting sustained AHRE in CIED patients.Material and Methods Consecutive subjects receiving CIED in Sandwell and West Birmingham Hospitals for 1999 to 2017 were enrolled and followed,for whom the baseline characteristics and device visiting records were reviewed.AHRE over 24 h as outcome event,a multivariable regression model was established to investigate risk factors for sustained AHRE.Receiver operating curve(ROC)was drawn do depict subjects developing sustained AHRE.Area under the curve(AUC)and was calculated to assess the predictive capability of the C2 HEST score in sustained AHRE.Kaplan-Meier curve and Log-rank test were conducted to evaluate the discriminative power of the C2 HEST score in grouping subjects for developing AHRE.Sensitivity analysis was also performed to assess the role of the C2 HEST score in subgroups of patients.Results 500 consecutive patients with CIED were enrolled with a mean 53.1 ± 33.9months of follow-up.44(8.8%)individuals developed sustained AHRE(>24h),yield a incidence of 2.09 per 100 patient-years.Heart failure and elderly(>75 years)were independent predictors for AHRE > 24 h.The C2 HEST showed moderate predictivity accuracy with AUC of 0.663(95% confidence interval,0.584-0.743).In the low-(0-1point),medium-(2-3 points)and high-risk(> 4 points)groups of patients,divided by the C2 HEST score,in incidences were 0.85,1.87 and 3.62 per 100 patient-years,respectively(Log-rank test P = 0.003).Conclusions The C2HEST score showed moderated predictive and discriminative ability in sustained AHRE among patients with CIED.