Abstract Body

Background and purpose

In Portugal in 2010, the FAMA study verified an overall prevalence of atrial fibrillation (AF) of 2.5% in a population sample older than 40 years and only 56.8% of patients with AF were prescribed adequate oral anticoagulation. The aim is to determine the prevalence of AF and to assess how these patients are being cared for: what anticoagulants are being prescribed and are they being prescribed as recommended?

Methods

Retrospective longitudinal study. This study was conducted in the Regional Health Administration of Northern Portugal and used a database that included 63,526 patients with code K78 of the International Classification of Primary Care between January 2016 and December 2018.

Results

The prevalence of AF among adults over 40 years in the northern region of Portugal was 2.3% in 2016, 2.8% in 2017, and 3% in 2018. From a total of 63,526 patients, 95.8% had an indication to receive anticoagulation therapy. Of these, 44,326 (72.9%) are being treated with anticoagulants: 17,936 (40.5%) were prescribed vitamin K antagonists and 26,390 (59.5%) were prescribed non-vitamin K antagonist anticoagulants. On the other hand, 2688 patients of the total (4.2%) had no indication to receive anticoagulation therapy. Of these 2688 patients, 1100 (40.9%) were receiving anticoagulants.

Conclusions

The prevalence of AF is 3%. Here, we report evidence of both undertreatment and overtreatment. Albeit having an indication, a considerable proportion of patients (27.1%) are not anticoagulated, and among AF patients without an indication to receive anticoagulation therapy, a considerable proportion (40.9%) are receiving anticoagulants.