Abstract 557: Abdominal Aortic Calcification Detected With routine Vertebral Fracture Assessment: A Strong Predictor of Cardiovascular Events
Introduction Aorta calcification is correlated with the degree of atherosclerosis in other arteries. Some studies showed that abdominal aorta calcification (AAC) detected by conventional x-ray systems can be a risk factor for cardiovascular outcomes. Vertebral fracture assessment (VFA) images performed by dual-energy x-ray absorptiometry (DXA), routinely used for osteoporosis screening, has been shown in previous studies to be able to detect aorta calcification with a minimal radiation dose of 0.01 mSv.
Hypothesis We hypothesized that AAC detected by VFA images can predict incidences of cardiovascular events.
Methods VFA images of 2500 subjects were evaluated by two physicians to score AAC according to an eight-point scoring scale. AAC-positive subjects (n=164) were divided into two groups according to mean AAC score. An age- and sex-matched random set of subjects (n=331) without AAC served as control group. Baseline cardiovascular risk factors, cardiovascular events (TIA, CVA, and myocardial infarction), and cardiovascular deaths were checked by the digital hospital information system. Median follow-up period 2.7 years. Cox regression method was applied for AAC classes versus cardiovascular outcomes using age and gender as covariates.
Results AAC-positive subjects were divided into two groups: low-AAC (score 1–3; n= 105, age average: 68±9 yr, 61% female), and high-AAC group (score>3; n= 59, age average: 71±11yr, 66% female). In the control group (score=0) age average was 66 ±8 yr, 66% female. Follow-up period for cardiovascular events was between 0.1 to 5 years (median: 2.7 year). Proportion of total (mortal or non-mortal) cardiovascular events within each group was: 1.2%, 6.7%, and 11.9% for control, low-AAC and high-AAC groups, respectively. Multivariate analysis using age and gender as covariates, showed significant higher cardiovascular events in both low-AAC (HR: 5.00; CI 95%: 1.4–17.2; p= 0.011) and high-AAC (HR: 7.00; CI 95%: 1.7–28.4; p= 0.007) compared to the control group.
Conclusion AAC routinely measured with VFA showed to be a strong predictor for cardiovascular events.