AbstractAimsAtrial fibrillation (AF) is becoming increasingly common. Traditional cardiovascular risk factors (CVRF) do not explain all AF cases. Blood‐based biomarkers reflecting cardiac injury such as high‐sensitivity troponin I (hsTnI) may help close this gap.MethodsWe investigated the predictive ability of hsTnI for incident AF in 45,298 participants (median age 51.4 years, 45.0% men) across European community cohorts in comparison to CVRF and established biomarkers (C‐reactive protein, N‐terminal pro B‐type natriuretic peptide).ResultsDuring a median follow‐up of 7.7 years, 1734 (3.8%) participants developed AF. Those in the highest hsTnI quarter (≥4.2 ng/L) had a 3.91‐fold (95% confidence interval (CI) 3.30, 4.63; p < .01) risk for developing AF compared to the lowest quarter (<1.4 ng/L). In multivariable‐adjusted Cox proportional hazards models a statistically significant association was seen between hsTnI and AF (hazard ratio (HR) per 1 standard deviation (SD) increase in log10(hsTnI) 1.08; 95% CI 1.01, 1.16; p = .03). Inclusion of hsTnI did improve model discrimination (C‐index CVRF 0.811 vs. C‐index CVRF and hsTnI 0.813; p < .01). Higher hsTnI concentrations were associated with heart failure (HR per SD 1.37; 95% CI 1.12, 1.68; p < .01) and overall mortality (HR per SD 1.24; 95% CI 1.09, 1.41; p < .01).ConclusionhsTnI as a biomarker of myocardial injury does not improve prediction of AF incidence beyond classical CVRF and NT‐proBNP. However, it is associated with the AF‐related disease heart failure and mortality likely reflecting underlying subclinical cardiovascular impairment.