Associations of cardiovascular disease risk factors and calcified atherosclerosis with aortoiliac bifurcation position: the MultiEthnic Study of Atherosclerosis.

We investigated associations of cardiovascular disease (CVD) risk factors and calcified atherosclerosis with aortoiliac bifurcation position. The bifurcation position was determined by measuring the distance from the aortoiliac bifurcation to the L5-S1 disk space (or aortoiliac bifurcation distance [AIBD]), using computed tomography scans. The 1711 study participants (51% male) had a mean age of 62 ± 10 years and a mean AIBD of 26 ± 15 mm. In multivariable linear regression, older age, male gender, smoking, hypertension, larger aortic diameter, and smaller lumbar height were each independently associated with a smaller AIBD (more caudal bifurcation position). In contrast, diabetes, elevated triglycerides, and increased pulse pressure were independently associated with a larger AIBD (more cephalad bifurcation position). These findings suggest that age-related bifurcation descent is associated with CVD markers for aortic disease. Future studies should assess whether the bifurcation position is an independent prognosticator for CVD.