Association between Body Mass Index and Mortality From Aortic Aneurysm and Dissection: A Prospective Cohort Study

The association between obesity and aortic diseases remains uncertain. We investigated the relationship between body mass index (BMI) and mortality from aortic aneurysm and dissection.

This population-based prospective cohort study used National Health Insurance Service health examination data from 15,146,946 Korean adults aged ≥18 years who underwent health screening between 2003 and 2006, with follow-up for mortality from aortic aneurysm and dissection through national death registry linkage until 2018. Multivariable Cox proportional hazards models estimated adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

Over a median follow-up of 14.3 years, 4,299 deaths from aortic disease were identified. A J-shaped association was observed between BMI and aortic disease mortality. Underweight (BMI <18.5 kg/m²: HR, 1.23; 95% CI, 1.04-1.45; p=0.013) and higher BMI categories, including upper-normal, overweight, and obese groups (e.g., BMI ≥35 kg/m²: HR, 3.40; 95% CI, 2.10-5.49; p<0.001), were associated with increased mortality compared with BMI 21-22.9 kg/m². The association was more pronounced in younger individuals. The excess risk associated with underweight was more prominent in women, whereas the association with higher BMI was steeper in men.

In this large nationwide general population cohort, BMI showed a J-shaped association with mortality from aortic aneurysm and dissection. Further studies are needed to determine whether maintaining BMI within a healthy range is associated with lower risk of mortality from aortic aneurysm and dissection.