EXPRESS: The prognostic value of abdominal aortic calcification in elder adults and its mediating effect for advanced age and all-cause mortality

The prognostic value of abdominal aortic calcification (AAC) for all-cause mortality and the relationship among severe AAC and other high-risk factors such as age remain uncertain. A total of 1390 participants from The National Health and Nutrition Examination Survey (NHANES, 2013-2014) were enrolled in the final analysis. Based on dual-energy X-ray absorptiometry (DXA) at lateral lumbar spine, the AAC Kauppila score was calculated. There were NHANES Public-Use Linked Mortality Files about mortality follow-up data from the date of survey participation. Kaplan-Meier survival curves and log-rank tests were used to evaluate the association between AAC and all-cause/CV-related mortality. In group with age < 60 years old (n=732), 36 participants (4.9%) were accompanied with severe AAC and 696 (95.1%) without severe AAC. In group with age > 60 years old (n=658), 158 participants (24.0%) were accompanied with severe AAC and 500 (76.0%) without severe AAC. Multivariate Cox proportional hazard regression models and Kaplan-Meier survival curves indicated that the presence of severe AAC was generally associated with an increased risk of all-cause mortality. The mediator analysis was performed to explore the relationships among age, severe AAC, and all-cause mortality. The results revealed the incremental effect of severe AAC on the elevated risk of all-cause mortality associated with advanced age. DXA-based severe AAC screening demonstrates significant prognostic value for all-cause and cardiovascular-related mortality, providing incremental risk stratification for high-risk populations. These findings may inform clinical decision-making and enhance public awareness of cardiovascular health.