Melanie Ganz MSc, Abstract Co-Author: Nothing to Disclose

Mads Nielsen PhD, Presenter: Nothing to Disclose

Marleen de Bruijne PhD, Abstract Co-Author: Research grant, AstraZeneca PLC

Erik B Dam PhD, Abstract Co-Author: Employee, SYNARC Inc

Morten Karsdal, Abstract Co-Author: Employee, Nordic Bioscience A/S Shareholder, Nordic Bioscience A/S

Claus Christiansen, Abstract Co-Author: Shareholder, Nordic Bioscience A/S Shareholder, SYNARC Inc

Cardiovascular diseases (CVD) are the prevalent cause of death in Europe and the United States. This is despite general acceptance that a healthy lifestyle and risk factor management can prevent the development of CVD. Furthermore, two-thirds of women who die suddenly from CVD have no previously recognized symptoms. Thus, it is essential to find effective and broadly applicable indicators of cardiovascular risk that may prompt timely intervention. Abdominal aortic calcifications (AAC) as observed by standard lumbar lateral radiographs can be predictors of cardiovascular mortality and correlate strongly with coronary artery calcifications. We investigated whether size, shape, and distribution of AACs related to mortality and how such prognostic markers performed compared to the state-of-the-art  marker on lumbar lateral radiographs, AC24, introduced by Kauppila et al.

For 308 post-menopausal women we quantified the number of abdominal aortic calcifications (AAC) and the percentage of the abdominal aorta that the lesions occupied in terms of their area, simulated area, thickness, wall coverage and length. We analysed inter-/intra-observer reproducibility and predictive ability of mortality after 8-9 years. This was done via a Cox regression with and without adjustment for biological risk factors leading to hazard ratios (HR).

The coefficient of variation was below 25% for all markers. The strongest individual predictors were the number of calcifications (HR=2.4, p<0.001) and the simulated area percentage (HR=2.96, p<0.001) of a calcified plaque and, unlike AC24 (HR=1.66, p<0.001), they allowed mortality prediction also after normalization for traditional risk factors. In a combined Cox regression model the strongest complementary predictors were the number of calcifications (HR=2.76, p<0.001) and the area percentage (HR=-3.84, p<0.001).

While AC24 definitely captures essential information about abdominal aortic calcifications (AAC), the results demonstrate that some of these novel markers may capture additional or complementary information. Therefore, the proposed radiographic AAC markers may allow improved screening and risk monitoring of CVD mortality.

New imaging biomarkers based shape, size and distribution of lumbar aortic calcifications as seen in lumbar lateral radiographs may allow improved screening and risk monitoring of CVD mortality.

Ganz, M, Nielsen, M, de Bruijne, M, Dam, E, Karsdal, M, Christiansen, C, Distribution, Size, and Shape of Abdominal Aortic Calcified Deposits and Their Relationship to Mortality in Postmenopausal Women.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034397.html