Clinical question: Is anticoagulation beneficial for patients with atrial fibrillation (Afib) and low CHA2DS2-VASc score (0 for men, 1 for women) or for those with one additional stroke risk factor?
Background: Guidelines nearly universally recommend anticoagulation for patients with a CHA2DS2-VASc of >2, but differ on recommendation for patients with a CHA2DS2-VASc of 1.
Study design: Cohort study.
Setting: Multiple national registries in Denmark.
Synopsis: Based on analysis, patients with very low stroke risk using the CHA2DS2-VASc score (0 for men, 1 for women) had particularly low stroke risk and did not appear to benefit from additional therapy with aspirin or warfarin, both at one year and at full follow-up (mean 5.9 years).
The addition of one stroke risk factor increased stroke risk without treatment significantly (three-fold increase). Hazard ratios favored treatment with warfarin in these patients, most notably with a reduction in all-cause mortality (though this was more significant at one year than at full follow-up).
Bottom line: Although guidelines differ on treatment strategy for patients with Afib and one stroke risk factor (i.e., CHA2DS2-VASc score of 1 for men, 2 for women), this study supports treatment with warfarin.
Citation: Lip GY, Skjöth F, Rasmussen LH, Larsen TB. Oral anticoagulation, aspirin, or no therapy in patients with nonvalvular AF with 0 or 1 stroke risk factor based on the CHA2DS2-VASc score. J Am Coll Cardiol. 2015;65(14):1385-1394.