Impact of anaemia severity on functional outcome in patients with cerebral venous thrombosis: a DOAC-CVT substudy

INTRODUCTION: Anaemia is an established risk factor for poor outcome in intracerebral haemorrhage and ischaemic stroke. We examined whether anaemia predicts poor outcome in cerebral venous thrombosis (CVT). PATIENTS AND METHODS: We used data of the DOAC-CVT study, which was an international, prospective observational cohort study in adult patients with CVT that ran from January 2021 to January 2024. Anaemia at admission was defined according to World Health Organization criteria. Poor outcome was defined as modified Rankin Scale (mRS) 3-6 at 6-months. Binary logistic regression, adjusted for age, recent delivery/puerperium, income country, cancer and intracranial haemorrhage, was applied. RESULTS: Of 619 patients in DOAC-CVT, 583 patients were included, of whom 157 (27%) had anaemia. Compared to patients without anaemia, patients with anaemia were slightly younger (median age 40 vs. 42 years), more often female (76% vs. 59%), from middle income countries (36% vs. 21%), more often had intracranial haemorrhage (48% vs. 32%) and cancer (5% vs. 2%). Anaemia was associated with poor functional outcome (mRS 3-6, 10% vs. 5%, aOR: 2.20, 95% Cl, 1.01-4.81), but not with mortality (3% vs. 1%, aOR: 3.54, 95% Cl, 0.68-18.31). When stratified by severity, moderate to severe anaemia was associated with poor functional outcome (aOR 2.88, 95% Cl, 1.14-7.38), but mild anaemia was not (aOR 1.64, 95% Cl, 0.60-4.55). DISCUSSION AND CONCLUSION: Anaemia at admission, especially moderate to severe, is a predictor for poor functional outcome in patients with CVT, highlighting the need for further studies on potential interventions.