C-reactive protein levels and risk of stroke and its subtype in Japanese: The Circulatory Risk in Communities Study (CIRCS)

BackgroundEpidemiological studies have shown high-sensitive C-reactive protein (hs-CRP) to predict cardiovascular disease. However, there are only limited studies on the effects of hs-CRP levels on risk of stroke especially stroke subtypes. We examined associations of hs-CRP levels with risks of total stroke and its subtypes.MethodsA prospective nested case-control study of Japanese 40-85 years of age was conducted using frozen serum samples collected from 13,521 men and women who participated in cardiovascular risk surveys from 1984 to 2001 for one community and 1989 to 1998 for the other two communities under the Circulatory Risk in Communities Study (CIRCS). Three control subjects per case were matched by sex, age, community, year of serum storage, and fasting status.ResultsBy the end of 2005, we identified 261 incident strokes (165 ischemic strokes and 96 hemorrhagic strokes). There was a positive association between hs-CRP and incidence of incidence of total stroke, ischemic stroke and lacunar infarction. After further adjustment for known cardiovascular risk factors, these relationships remained statistically significant. The multivariable conditional odds ratios associated with 1-SD increment of log-transformed hs-CRP were 1.17(1.01-1.35) for total stroke, 1.27(1.06-1.52) for ischemic stroke, and 1.24(1.00-1.55) for lacunar infarction. The association between hs-CRP levels and incidence of ischemic stroke did not vary by sex, age, body mass index and smoking. No associations were found between hs-CRP levels and risk of hemorrhagic stroke.Conclusionshs-CRP predicts the incidence of total and ischemic strokes among middle-aged Japanese men and women.