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Updated: May 11, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Factor VIII in the setting of acute ischemic stroke among patients with suspected hypercoagulable state
Tiffany R Chang1, Karen C Albright, Amelia K Boehme
11Stroke Program, Department of Neurology, Tulane University School of Medicine, New Orleans, LA, USA.
Background:
Elevation of factor VIII is associated with higher risk of large vessel arterial occlusions including stroke.
Methods:
Factor VIII levels were examined in consecutive patients with acute ischemic stroke (AIS) presenting to a single center between July 2008 and May 2012. Factor VIII levels exceeding the laboratory reference range were considered elevated (>150%).
Results:
Factor VIII level was elevated in 72.4% (84 of 116) of the patients. Elevated factor VIII level was more frequent in blacks, diabetics, and patients who were anemic. Patients with elevated factor VIII had higher median baseline National Institute of Health Stroke Scale (NIHSS; 5 vs 2, P = .0295) and twice the frequency of neuroworsening (21.4% vs 9.4%), but discharge NIHSS and modified Rankin Scale were similar in the groups.
Conclusions:
High factor VIII level was found in the majority of tested patients with AIS. Several baseline differences were found between patients with normal and high factor VIII levels, but no differences were identified in outcome.
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