Seventeen case series, six grouped case series and 40 case reports (n=492 participants) were included in the review. Three studies were prospective and 60 were retrospective. Case series scored between 2.0 and 12.7 on the Downs and Black checklist.
Haemorrhagic complications were experienced by 7.7% of patients (mostly within 72 hours of haemorrhage) and thromboembolic complications were experienced by 6.1% (mostly after 72 hours post-haemorrhage). Statistical analyses demonstrated a significant increase in risk of thromboembolic complications when anticoagulation was restarted after 72 hours (p=0.006). There was a trend towards an increase in haemorrhagic complications when anticoagulation was restarted before 72 hours, but this was not statistically significant (p=0.0727).
Univariate analyses identified that re-haemorrhage was more common in younger patients, where haemorrhage was caused by trauma, subdural haematomas and failure to reverse anticoagulation. Thromboembolic complications were more common in younger patients and patients with spinal haemorrhage, multiple haemorrhages and non-traumatic causes of initial haemorrhage. Patients restarted at lower intensity anticoagulation were significantly more likely to experience a thromboembolic complication than patients restarted at previous intensity anticoagulation (p<0.0001).
Other results were reported in the review. Sensitivity analysis results were not reported.