http://orcid.org/0000-0002-5994-9304Magnus Nakrem Lyngbakken1,2, http://orcid.org/0000-0002-7701-9303Peter Selmer Rønningen3,4, Magnar Gangås Solberg3,4, http://orcid.org/0000-0002-7681-8621Trygve Berge3, Jon Brynildsen1, Erika Nerdrum Aagaard1,2, Brede Kvisvik1,2, http://orcid.org/0000-0003-2114-3134Helge Røsjø2,5, http://orcid.org/0000-0003-4265-3598Kjetil Steine1,4, Arnljot Tveit3,4, Torbjørn Omland1,2 Correspondence to Dr Magnus Nakrem Lyngbakken, Department of Cardiology, Division of Medicine, Akershus University Hospital, Lorenskog 1478, Norway; [email protected] Abstract Objective Atrial fibrillation is a common arrhythmia associated with risk of stroke, heart failure and death. We aimed to elucidate the associations of cardiac biomarkers, echocardiographic left atrial volumetric indices and risk of prevalent and incident atrial fibrillation in the general population. Methods We assessed cardiac troponin T (cTnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), growth differentiation factor 15 (GDF-15), maximum (LAVimax) and minimum (LAVimin) indexed left atrial volumes and left atrial emptying fraction (LAEF) in subjects born in 1950 participating in the prospective observational cohort, Akershus Cardiac Examination 1950 Study. The Cohorts for Heart and Ageing Research in Genomic Epidemiology for Atrial Fibrillation risk score and sex was used to adjust for residual risk of atrial fibrillation.