Infection, inflammation, and cerebrovascular ischemia

Hemostatic and inflammatory pathways mutually interact with each other. Increased inflammatory parameters are a sequel of and also a risk factor for cerebral thrombosis and ischemia. Ischemic stroke is followed by an acute-phase response that is characterized by a transient rise in fibrinogen, leukocyte count, and several cytokines. This article focuses on inflammatory changes that precede cerebral ischemia and on inflammation/infection as a risk factor for stroke and transient ischemic attack (TIA). Inflammatory parameters and vascular diseases and risk factors. The leukocyte count is positively associated with the risk for ischemic stroke and myocardial infarction.1,2 The granulocyte count appears to contribute mainly to such elevated risk. A recent epidemiologic study found that the monocyte count also correlated with an increased risk for myocardial ischemia.3 High plasma fibrinogen levels are a risk factor for stroke and myocardial infarction(MI).4 Moreover, several serum glycoproteins, mostly acute-phase reactants, were shown to be correlated with the severity of coronary atherosclerosis.5 Although the above inflammatory parameters appear to independently predict the risk of ischemic diseases, several vascular risk factors are themselves correlated with an increase in inflammatory parameters. We studied the association of leukocyte count, fibrinogen, and C-reactive protein (CRP) with vascular risk factors in the control group of our recent case-control study investigating acute infection as a risk factor for stroke.6,7 These control subjects were randomly selected from the population and were matched to stroke patients for sex and age. Subjects with the following conditions were excluded from the analysis: malignancies, acute or chronic inflammatory diseases; recent trauma, surgery, and vascular diseases. In an ANOVA model with several risk factors and ischemic diseases, diabetes mellitus was associated with higher leukocyte count, fibrinogen and CRP. High age was correlated with increased leukocyte count and fibrinogen; Smoking and a history of stroke …