Prior antiplatelet or anticoagulant therapy and mortality in stroke

OBJECTIVE: To examine the influence of previous antiplatelet or anticoagulant therapy on subsequent stroke mortality at different time points up to 1 year post stroke.

DESIGN: Data were examined from a hospital register collected over 5 years (2004-2008).

SETTING: A single large university hospital.

PARTICIPANTS: Every adult (18+ years) admitted with an acute stroke.

MAIN OUTCOME MEASURES: Mortality risks at 7, 30, 60, 90 and 365 days were assessed using logistic regression following ischaemic and haemorrhagic stroke, adjusting for age, gender, premorbid Rankin and stroke type.

RESULTS: 3308 patients with first or recurrent stroke were included (53% women, mean age 77.7±11.5 years, 86% ischaemic stroke). One-year mortality was 35.2% (999) for ischaemic stroke and 48.3% (227) for haemorrhagic stroke. Compared with no previous therapy, the mortality following ischaemic stroke for those already receiving antiplatelets or anticoagulants was not associated with increased mortality at any time points up to 1 year after presentation in the fully adjusted model. However, patients with haemorrhagic stroke had a worse prognosis at all time points after standard risk factor adjustment. For patients who used aspirin or warfarin prior to haemorrhagic stroke compared with no use, ORs (95% CIs) were 1.31 (0.64 to 2.68) and 2.91 (1.23 to 6.89) for 7 days, 2.36 (1.18 to 4.71) and 2.37 (1.00 to 5.61) for 30 days, 2.18 (1.10 to 4.29) and 2.86 (1.20 to 6.84) for 60 days, 2.56 (1.27 to 5.13) and 2.82 (1.16 to 6.86) for 90 days and 1.67 (0.89 to 3.12) and 2.44 (1.06 to 5.62) for 365 days.

CONCLUSIONS: Prior antiplatelet or anticoagulant use was associated with increased mortality following HS but not IS after adjustment for common factors associated with a poor prognosis. The reasons for this poor prognosis and potential therapeutic options need exploring in future studies.