Background and purpose: There is growing evidence of the prognostic importance of C-reactive protein (CRP) in ischemic stroke. However, the independent value of CRP at different stages after stroke has not been established. Therefore, we assessed the prognostic values of CRP in ischemic stroke. We also compared the relation of CRP at admission and discharge with 1-year outcome.
Methods: One hundred ninety-three patients were included in a derivation set (n=128) and a validation set (n=65). Serum CRP was measured, within 24 hours after index ischemic stroke, within 48 to 72 hours, and at hospital discharge. We examined the association between the level of CRP at different stages after stroke and outcome. We adjusted for the possible confounding effect using a multivariate Cox proportional hazard model.
Results: A cutoff point of 1.5 mg/dL for CRP at discharge provided optimum sensitivity and specificity for adverse outcome, based on the receiver operator curves. CRP at admission (hazard ratio [HR] 2.78, 95% CI 1.45 to 5.33; P=0.0021) and discharge (HR 9.42, 95% CI 4.27 to 19.05; P<0.0001) were predictors of the combined end point of new vascular events or death at 1 year. CRP at hospital discharge was the strongest independent marker of adverse outcome (HR 7.42, 95% CI 2.75 to 20.03; P=0.0001). These results were confirmed in the validation set (HR 15.66, 95% CI 3.36 to 72.97; P=0.0005).
Conclusions: CRP is a marker of increased 1-year risk in ischemic stroke. CRP at discharge is better related to later outcome and could be of greater utility for risk stratification. These findings are consistent with the hypothesis that elevated CRP may predict future cardiovascular events or death.