Abstract TP170: Persistently Elevated Factor VIII In Acute Ischemic Stroke Is Associated With Higher CRP, Lower Baseline NIHSS, And Longer Length Of Hospital Stay

Abstract

Objective: We sought to determine the proportion of patients with elevated factor VIII (FVIII) levels whose FVIII levels remain elevated after the acute phase of stroke, and the patient characteristics that predict sustained elevation of FVIII levels. Background: Factor VIII plays a major role in the fluid phase of blood coagulation. Elevated FVIII has been shown to increase risk of venous and arterial thrombosis. The importance of screening for elevated FVIII after a first thrombotic event especially acute ischemic stroke (AIS) has not been adequately investigated. Design/Methods: We reviewed FVIII levels taken at baseline and follow-up in patients with AIS treated at our stroke center from July 2008 to June 2012. Elevated FVIII was defined as >150%. Baseline demographics, laboratory data, clinical course, outcomes, and time to follow-up were collected in patients with elevated FVIII at baseline and data was compared in patients who had normalized FVIII with patients whose FVIII remained elevated at least 7 days later. Results: Repeat FVIII levels were available for 34/111 patients with elevated FVIII level with AIS. FVIII remained elevated in 68% after a median interval of 110 days. Factors associated with persistent elevation included higher baseline FVIII level (239 vs 185%, p=0.015), elevated CRP (73.3 vs 12.5%, p=0.008), lower baseline NIHSS (4 vs 8, p=0.046), and longer length of hospital stay (8 vs. 3, p=0.0063). Normalization of FVIII was associated with tPA use (54.5% vs 13%, p=0.016). No relationship was found between persistently elevated FVIII and baseline demographics, clinical course and outcomes. Conclusion: Persistently elevated FVIII after AIS may be predicted by higher baseline levels and elevations in CRP. Despite worse baseline stroke severity, patient with normalization of FVIII had similar outcomes as those with persistent elevation, which may be explained by the higher use of tPA in the normalized group. The relevance of elevated FVIII in stroke is not well understood. Our preliminary results suggest elevations persist in the majority and may not merely represent an acute phase reactant.