The Association between Inflammatory Markers and Carotid Atherosclerosis Is Sex Dependent: the Tromsø Study

Background: The presence of echolucent artery plaques is associated with increased risk of cardiovascular events as compared to echogenic plaques. Whether inflammatory markers are associated with carotid plaque morphology is questioned. Methods: 5,341 individuals were examined with ultrasonography of the right carotid artery. Of these, 3,205 had carotid plaque(s), in whom plaque area (mm2) and plaque echogenicity, expressed as the computer-assisted gray scale median (GSM), were determined. White blood cell count (WBC), fibrinogen and C-reactive protein (CRP) were analyzed, as well as other cardiovascular risk factors. In multiple linear and logistic regression models, we determined the relationship between plaque area and echogenicity, and inflammatory markers. Results: Women and men with carotid plaque(s) had significantly elevated levels of WBC and fibrinogen, but not CRP, as compared to subjects without plaques. All inflammatory markers were significantly associated with plaque area in men. WBC was significantly associated with plaque echogenicity in women, whereas no association was found between fibrinogen and CRP and plaque echogenicity in either gender. Conclusions: This cross-sectional study showed sex-dependent differences in associations between measures of carotid atherosclerosis and inflammatory markers. CRP did not discriminate echolucent from echogenic carotid plaques in either gender. Our data highlight the importance of sex-specific analyses in future studies.