Basal Metabolic Rate and Risk of Aortic Aneurysm and Dissection: Results From Two Cohort Studies

Basal metabolic rate (BMR) may play a key role in the prevalence of aortic aneurysm and dissection. This study aimed to explore the association between BMR and the risk of abdominal aortic aneurysm (AAA), thoracic aortic aneurysm (TAA), and aortic dissection.

Mendelian randomization (MR) analyses were conducted to examine the causal relationship between BMR and aortic aneurysm and dissection. The data from 360,292 participants in the UK Biobank were analyzed using Cox regression models and restricted cubic spline. The results were further validated in a Chinese cohort of 10,169 participants for AAA.

The two-sample MR showed that BMR was associated with increased risk of AAA (odds ratio [OR] = 1.49, 95% confidence interval [CI] 1.20-1.84, P < 0.00), TAA (OR = 2.13, 95% CI 1.71-2.64, P < 0.00), and aortic dissection (OR = 1.94, 95% CI 1.32-2.86, P < 0.00). Multivariable MR confirmed these associations after adjusting for confounders. In the UK Biobank cohort, multivariable analysis showed that the highest BMR quartile was associated with increased risk of AAA and TAA (hazard ratio= 1.70, 95% CI 1.27-2.27, P < 0.01; hazard ratio= 2.01, 95% CI 1.29-3.13, P < 0.01). The restricted cubic spline model demonstrated a J-shaped relationship between BMR and AAA as well as TAA (nonlinear P < 0.001). In the Chinese cohort, Model 4 showed that higher BMR quartiles were associated with increased AAA risk (OR = 1.78, 95% CI 1.33-2.23, P = 0.01).

MR analyses suggest a causal relationship between BMR and the risk of AAA and TAA, which is further validated by positive associations in two large cohorts, highlighting BMR's potential utility in clinical risk stratification and management.