Association of Anaemia With Higher Mortality and Disability After Subarachnoid Haemorrhage: A Single-Centre Cohort Study

Cureus. 2025 Apr 26;17(4):e83031. doi: 10.7759/cureus.83031. eCollection 2025 Apr.

Abstract

Background: Critical care management in subarachnoid haemorrhage (SAH) aims to facilitate neuroprotection and prevent secondary neurological insults. Anaemia after SAH leads to reduced cerebral oxygen delivery and poor outcomes. This study aimed to investigate the association between anaemia and mortality and morbidity outcomes in patients with SAH in tertiary centres, as well as evaluate the impact of blood transfusions on outcomes in anaemic SAH patients. Methods: We performed a retrospective study of 987 patients with SAH at a tertiary neurocritical care centre between September 2016 and September 2018. Data were collected on baseline characteristics, World Federation of Neurosurgical Societies SAH grade, secondary insults such as anaemia and hydrocephalus, and units of blood transfused. The primary outcome was to investigate the correlation between anaemia and 28-day Modified Rankin Scale (MRS) score. Secondary outcomes were delayed neurological deficits, length of stay and death in the intensive care unit (ICU). Anaemia was defined as haemoglobin (Hb) ≤ 95 g/L, and severe anaemia as Hb≤80 g/L. Results: Of the patients, 28.7% had anaemia and 12% had severe anaemia. Anaemia after SAH was associated with an increased risk of death or severe disability (p<0.001), worse survival outcomes (p<0.001) and increased length of stay in ICU (p<0.001).

Conclusions: Anaemia after SAH is associated with a significant increase in mortality and morbidity and should be monitored closely and corrected.

Keywords: acute subarachnoid haemorrhage; anaemia; blood transfusion; intracerebral aneurysms; neurointensive care unit.