Hs-CRP in stroke: A meta-analysis

Background: Studies on high-sensitivity C-reactive protein (hs-CRP) and stroke risk have yielded conflicting results.

Objective: To determine whether elevated baseline hs-CRP presents an independent risk for different kinds of strokes by conducting a meta-analysis.

Methods: The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure and Wanfang databases were systematically searched for prospective observational studies published until January 2015. Studies reporting hs-CRP levels and adjusted risk estimates of different stroke subtypes by hs-CRP were selected. Pooled results were expressed as adjusted risk ratios (RRs), with corresponding 95% confidence intervals (CI) for the highest versus the lowest hs-CRP category.

Results: Twelve studies involving 2269 strokes, of which 2436 were ischemic and 655 were hemorrhagic, were identified from 66,560 participants. When comparing the highest with the lowest hs-CRP category, the pooled RR of ischemic strokes was 1.46 (95% CI 1.27-1.67) in a fixed-effect model. The pooled RRs of all strokes and hemorrhagic stroke were 1.23 (95% CI: 0.997-1.51) and 0.82 (95% CI 0.59-1.13), respectively. The risk of ischemic strokes seemed higher in men (RR 1.66; 95% CI 1.23-2.24).

Conclusions: Elevated baseline hs-CRP levels are independently associated with excessive ischemic stroke risk but exhibit no clear effect on hemorrhagic stroke.