AF genetic risk scores were associated with incident AF (HR 1.67; 95% CI 1.47-1.90 for highest vs lowest quartile) and cardioembolic stroke, but offered small improvements in risk discrimination.
Cohort (n=22,456)
Yes
Do AF genetic risk scores improve risk stratification for incident AF and cardioembolic stroke compared to clinical risk factors alone?
AF genetic risk scores are independently associated with incident AF and cardioembolic stroke, but offer only small improvements in discrimination over clinical risk factors alone.
Effect estimate: HR 1.67 (95% CI 1.47-1.90)
p-value: p=9.3x10^-15
Background: Atrial fibrillation (AF) has a substantial genetic basis. Identification of individuals at greatest AF risk could minimize the incidence of cardioembolic stroke. Methods: To determine whether genetic data can stratify risk for development of AF, we examined associations between AF genetic risk scores and incident AF in 5 prospective studies comprising 18 919 individuals of European ancestry. We examined associations between AF genetic risk scores and ischemic stroke in a separate study of 509 ischemic stroke cases (202 cardioembolic 40%) and 3028 referents. Scores were based on 11 to 719 common variants (≥5%) associated with AF at P values ranging from <1×10 −3 to <1×10 −8 in a prior independent genetic association study. Results: Incident AF occurred in 1032 individuals (5.5%). AF genetic risk scores were associated with new-onset AF after adjustment for clinical risk factors. The pooled hazard ratio for incident AF for the highest versus lowest quartile of genetic risk scores ranged from 1.28 (719 variants; 95% confidence interval, 1.13–1.46; P =1.5×10 −4 ) to 1.67 (25 variants; 95% confidence interval, 1.47–1.90; P =9.3×10 −15 ). Discrimination of combined clinical and genetic risk scores varied across studies and scores (maximum C statistic, 0.629–0.811; maximum ΔC statistic from clinical score alone, 0.009–0.017). AF genetic risk was associated with stroke in age- and sex-adjusted models. For example, individuals in the highest versus lowest quartile of a 127-variant score had a 2.49-fold increased odds of cardioembolic stroke (95% confidence interval, 1.39–4.58; P =2.7×10 −3 ). The effect persisted after the exclusion of individuals (n=70) with known AF (odds ratio, 2.25; 95% confidence interval, 1.20–4.40; P =0.01). Conclusions: Comprehensive AF genetic risk scores were associated with incident AF beyond associations for clinical AF risk factors but offered small improvements in discrimination. AF genetic risk was also associated with cardioembolic stroke in age- and sex-adjusted analyses. Efforts are warranted to determine whether AF genetic risk may improve identification of subclinical AF or help distinguish between stroke mechanisms.
Lubitz et al. (Sat,) conducted a cohort in Atrial fibrillation (n=22,456). AF genetic risk scores vs. Lowest quartile of genetic risk scores was evaluated on Incident AF (HR 1.67, 95% CI 1.47-1.90, p=9.3x10^-15). AF genetic risk scores were associated with incident AF (HR 1.67; 95% CI 1.47-1.90 for highest vs lowest quartile) and cardioembolic stroke, but offered small improvements in risk discrimination.