Atrial fibrillation patients who sustained warfarin-associated intracerebral haemorrhage have poor neurological outcomes: results from a matched case series

摘要

Coagulopathy-associated intracerebral haemorrhage has become increasingly common because of the rising demand in the ageing population for anticoagulation for atrial fibrillation. This study compared the clinical features and neurological outcomes of intracerebral haemorrhage in patients with atrial fibrillation who were prescribed warfarin with those who were not. Methods: This was a retrospective matched case series of patients with intracerebral haemorrhage from three tertiary hospitals in Hong Kong from 1 January 2006 to 31 December 2011. Patients who developed intracerebral haemorrhage and who were prescribed warfarin for atrial fibrillation (ICH-W group) were compared with those with intracerebral haemorrhage and not prescribed warfarin (ICH-C group); they were matched for age and gender in 1:1 ratio. Clinical features and neurological outcomes were compared, and the impact of coagulopathy on haematoma size was also studied. Results: We identified 114 patients in the ICH-W group with a mean age of 75 years. Both ICH-W and ICH-C groups had a median intracerebral haemorrhage score of 2. There was a non–statistically significant trend of higher intracerebral haemorrhage volume in the ICH-W group (12.9 mL vs 10.5 mL). The median modified Rankin Scale and the proportion with good recovery (modified Rankin Scale score ≤3) at 6 months were comparable. Nonetheless, ICH-W patients had higher hospital mortality (51.8% vs 36.0%; P=0.02) and 6-month mortality (60.5% vs 43.0%; P=0.01) than ICH-C patients. Overall, 60% of ICH-W patients had their admission international normalised ratio within the therapeutic range during intracerebral haemorrhage, and 14% had a subtherapeutic admission international normalised ratio. International normalised ratio at admission was not associated with intracerebral haemorrhage volume or neurological outcome. Conclusion: Warfarin-associated intracerebral haemorrhage in patients with atrial fibrillation carried a higher stroke mortality than the non-warfarinised patients. New knowledge added by this study Warfarin-associated intracerebral haemorrhage (ICH) carries a high mortality. Implications for clinical practice or policy The reversal of coagulopathy after warfarin-associated ICH was often incomplete. Given the high mortality after warfarin-associated ICH, newer oral anticoagulants may be a safer alternative in patients with a high risk of cerebral bleeding. As a class of drugs, they are associated with fewer ICHs. [Abstract in Chinese] Introduction Atrial fibrillation (AF) is associated with an increased risk of stroke or systemic thromboembolism. Approximately 5% of AF patients develop stroke or other embolic events each year. 1 Anticoagulation with warfarin, a vitamin K antagonist, reduces stroke risk in AF patients by 64%. 2 It has been the drug of choice for many years in both primary and secondary stroke prevention in AF. Unfortunately, anticoagulation increases the risk of bleeding, and intracerebral haemorrhage (ICH) has been the most life-threatening bleeding complication of concern. This study aimed to compare the clinical features and neurological outcomes of ICH in warfarinised AF patients with those in non-warfarinised patients. Methods This was a retrospective matched case series of consecutive patients with first acute ICH admitted to the medical unit of three tertiary hospitals in Hong Kong—Princess Margaret Hospital (PMH) and Caritas Medical Centre (CMC) in Kowloon West, and Queen Elizabeth Hospital (QEH) in Kowloon Central—from 1 January 2006 to 31 December 2011. The three hospitals cover about one quarter of the 7 million population in Hong Kong. It is a general practice in Hong Kong that patients with acute stroke symptoms are admitted to the medical unit (to acute stroke unit first, and to general medical ward if acute stroke unit is full) for further management, with computed tomography (CT) brain scans done within 24 hours of admission. If ICH is identified, a neurosurgeon will be consulted for assessment. Therefore ICH patients in the medical unit are a good indication of the general ICH population. We searched our electronic database for all patients aged 18 years or above who developed first ICH in the presence of anticoagulation with warfarin for non-valvular AF (ICH-W group) from the three hospitals, and matched them with a comparison group (ICH-C group) without taking warfarin at a 1:1 ratio for age (±1 year), gender, and admission year. The comparison group comprised patients from the medical unit of PMH (principal study centre) who had a first episode of ICH without anticoagulation, regardless of any AF. Patients with isolated subdural, subarachnoid, or intraventricular haemorrhage were excluded. We retrieved and compared the data regarding neurological impairment and investigation findings, estimated the ICH volume on CT through the ABC/2 method, and calculated the ICH score. 3 4 Hospital mortality and 6-month modified Rankin Scale score (mRS, 0-6