Abdominal Aorta Calcification Identified on DXA Scans and the Risk of Mortality in Adults.

Background: Abdominal aortic calcification (AAC) on lateral lumbar radiographs increases the risk of cardiovascular events and mortality. However, data on the association between AAC detected in dual energy X-ray absorptiometry (DXA) and the risk of mortality in the general population are scarce.

Methods: The present study was based on data from participants aged ≥40 years in the National Health and Nutrition Examination Survey (NHANES) cycle of 2013 to 2014. Vertebral assessment of lateral spine DXA scans was used to provide AAC measurements at vertebrae L1-L4. The extent of AAC was defined according to the Kauppila AAC-24 scores (0-1, 2-5, ≥6), and the NHANES 2019 public-use linked mortality files were used to assess mortality status.

Results: Of the 2,962 participants who were included in this study, with a mean age of 57.4 years and a median follow-up of 69.9 months, 252 (8.5%) died. Of the deaths, 84 (33.3%) occurred due to cardiovascular disease. The Cox proportional hazards models revealed that participants with AAC-24 scores ≥6 were 1.7 times more likely to die than those with AAC-24 scores 0-1 (Hazard ratio, 1.75; 95% confidence interval, 1.13-2.71). Moreover, older adults and women with AAC-24 scores ≥6 were 2.8 and 2.4 times more likely to die than their counterparts with AAC-24 scores 0-1, respectively. Conversely, a non-significant risk of cardiovascular mortality was found among participants with AAC-24 scores ≥6.

Conclusions: The extent of AAC detected on vertebral fracture assessment DXA was associated with an increased risk of all-cause mortality in adults, particularly older adults and women.