SummaryThe aims of this study were to investigate trends in the incidence of diagnosed atrial fibrillation (AF), and to identify factors associated with the prescription of antithrombotics (ATs) and to identify the persistence of patients with oral anticoagulant (OAC) treatment in primary care. Data were obtained from 400 Italian primary care physicians providing information to the Health Search/Thales Database from 2001 to 2004. The age-standardised incidence of AF was: 3.9–3.0 cases, and 3.6–3.0 cases per 1,000 person-years in males and females, respectively. During the study period, 2,016 (37.2%) patients had no prescription, 1,663 (30.7%) were prescribed an antiplatelet (AP) agent, 1,440 (26.6%) were prescribed an OAC and 301 (5.5%) had both prescriptions. The date of diagnosis (p = 0.0001) affected the likelihood of receiving an OAC. AP, but not OAC, use significantly increased with a worsening stroke risk profile using the CHADS2 risk score. Older age increased the probability (p < 0.0001) of receiving an AP, but not an OAC. Approximately 42% and 24% of patients persisted with OAC treatment at one and two years, respectively, the remainder interrupted or discontinued their treatment. Underuse and discontinuation of OAC treatment is common in incident AF patients. Risk stratification only partially influences AT management.