Though such associations have not presently been reported regarding the other biomarkers, it is possible that the smaller diameters of the aneurysms in our study precluded the use of these biomarker concentrations to identify AA, and may, thus, partly explain the negative inverse association between sCD40L and AA and the lack of associations between AA and high levels of syndecan-1 and thrombomodulin, respectively. This evidence concerns the gene THBD and aneurysm.