- The risk of recurrent acute ischaemic stroke (AIS) is higher in atrial fibrillation (Afib) patients having a stroke despite being on therapy with an oral anticoagulant (OAC).
Why this matters
- Findings highlight the need for preventive strategies for this high-risk patient group.
- An individual patient data analysis of 7 prospective cohort studies included 5314 patients with Afib and cerebral ischaemia.
- Patients who received oral anticoagulant (vitamin K antagonists [VKA] or direct OAC [DOAC]) prior to index event (OACprior) were compared with those who did not receive prior anticoagulation (OACnaive).
- Primary outcome: recurrent AIS; secondary outcomes: symptomatic intracranial haemorrhage (ICH) and mortality.
- Funding: None disclosed.
- Overall, 5136 (96.7%) patients had an ischaemic stroke (median National Institutes of Health Stroke Scale on-admission, 6 [interquartile range, 2-12]).
- No significant difference was observed in the median CHA2DS2-VASc score between OACprior and OACnaive (P=.103).
- During 6128 patient-years of follow-up, 289 patients had AIS (4.7% per year [95% CI, 4.2-5.3%]), 90 had ICH (1.5% per year [95% CI, 1.2-1.8%]) and 624 died (10.2% per year [95% CI, 9.4-11.0%]).
- OACprior was associated with an increased risk for AIS (HR, 1.6; 95% CI, 1.2-2.3; P=.005) but not ICH (HR, 1.1; 95% CI, 0.5-2.3; P=.811) and mortality (HR, 1.1; 95% CI, 0.8-1.4; P=.667).
- AIS risk did not decrease in patients who changed the type of anticoagulation therapy (n=307) vs those who did not change (n=585, HR 1.2; 95% CI, 0.7-2.1)
- Risk of bias.
- OACprior was determined by history but not by last OAC intake time.