Background Anticoagulation therapy with vitamin K antagonist (VKA) is a treatment used for prevention of ischaemic stroke associated with non-valvular atrial fibrillation (NVAF). Novel oral anticoagulants (NOAC) (rivaroxaban, dabigatran, apixaban) do not have limitations related to monitoring of anticoagulation, and have been shown to be at least as effective as VKA.¹

Purpose To estimate the comorbidities and incidence rates for stroke in NVAF patients treated with VKA and with NOAC.

Material and methods This was an observational, non-interventional, retrospective cohort study of adult patients diagnosed with NVAF during the study period June 2013 to June 2016.

Results 5231 patients were included in the study with a diagnosis of NVAF (4940 with VKA and 291 with NOAC), of whom 63% (n=3.306) had permanent AF, 22% (n=1.135) paroxysmal AF and 15% (n=790) persistent AF. The gender distribution showed that 49% (n=2589) were men and 51% (n=2642) were women. The proportion of NVAF by age was 4.5% (n=233) of patients younger than 60 years, 16.5% (n=861) of patients aged 60–70 years, 47% (n=2460) of patients aged 70–80 years and 32.1% (n=1677) of patients >80 years. The most common comorbidities were hypertension (70%, n=3698) and congestive heart failure (42%, n=2201).

Regarding ischaemic stroke rates per 100 patient years, we found 2.73% of all VKA treated patients and 2.05% of all NOAC treated patients suffered an ischaemic stroke. We did not found a significant overall difference between stroke and different oral anticoagulants used (p=0.244). 86% (n=148) had ischaemic stroke and 12% (n=21) had haemorrhagic stroke; 2% (n=4) unknown.

Conclusion Comorbidities observed are in line with other studies conducted in NVAF and, in common with them, the disease increases with age. Rates of stroke or systemic embolism in both cohorts of NVAF did not differ by treatment assignment.

References and/or acknowledgements 1. Patel MR, Mahaffey KW, Garg J, et al, ROCKET AF Investigators. Rivaroxaban versus warfarin in nonvalvular atrial fibrillation. N Engl J Med2011;365:883–91.

No conflict of interest