Atrial fibrillation (AF) increases stroke risk fivefold. Oral anticoagulation (OAC) with warfarin reduces the risk of stroke by 64%. Direct oral anticoagulants are non-inferior to warfarin in preventing stroke in non-valvular AF, but have a lower risk of fatal intracranial haemorrhage. We determined how many patients discharged with a diagnosis of ischaemic stroke and AF were prescribed OAC, and established reasons for, and associations with, non-prescription of OAC.
All patients discharged with a diagnosis of ischaemic stroke and AF during the four-year period between 2013 and 2016 within NHS Highland were included in the study. Patients who started OAC after a period of treatment with antiplatelets were considered as being treated with OAC. Electronic patient records provided demographics, CHA2DS2-VASc and HAS-BLED scores and information on why patients were not started on OAC.
A total of 181 patients were discharged with a diagnosis of ischaemic stroke and AF over the study period: 52.5% (n=95) were female (p=0.45); 35.4% (n=64) were discharged without OAC. The median CHA2DS2-VASc score for patients not treated with OAC was 5 (interquartile range [IQR] 4–6). The median HAS-BLED score was 3 (IQR 2.5–4). There was no difference in rate of OAC prescription between men and women (67% vs. 62%, p=0.45). Patients 80 years of age or older were significantly less likely to be prescribed OAC on discharge than those under 80 years (54% vs. 76%, p=0.002). The two most common reasons for withholding OAC were concern over bleeding risk and falls. Patients treated at a hospital with a stroke unit were no more likely to be discharged on OAC compared with those treated at hospitals without a stroke unit (66% vs. 62%, p=0.64). Of patients not treated with OAC, 64% (n=41) were discharged on long-term antiplatelet drugs.
In conclusion, raising awareness of the relatively low risk of major bleeding, even in elderly patients and in those at risk of falls, might help increase OAC usage and reduce recurrent strokes.