Purpose: Using data from the GARFIELD Registry we sought to determine the effect of accompanying coronary artery disease (CAD) on outcomes in atrial fibrillation (AF) patients. Methods: The study population comprised consecutively recruited patients with newly diagnosed (≤6 weeks) non-valvular AF and ≥1 additional investigator-defined stroke risk factor(s). The effect of CAD on 1-yr outcomes was determined, adjusting for age, sex, heart failure, LV dysfunction, hypertension, diabetes and stroke/TIA. Results: 20% of the 10,608 AF patients had CAD. They were older, less likely to be female and had a higher risk profile than patients without CAD. After adjustment, rates of death (HR 1.41, 95% CI 1.04-1.89) and acute coronary syndrome (HR 4.13, 95% CI 2.57-6.62) at 1 year were higher in CAD patients (HR 1.41, 95% CI 1.04-1.89) whereas those for stroke/systemic embolism (HR 1.19, 95% CI 0.77-1.86) and major bleed (HR 1.28, 95% CI 0.68-2.41) were similar. After additional adjustment for antithrombotic treatment only ACS remained significant (HR 3.91, 95% CI 2.41-6.33). View this table: Conclusions: In this observational study, AF patients with CAD had a higher risk profile than those without CAD. AF patients with CAD were at higher risk of ACS at 1 year, once treatment differences were taken into account.