Increases to thoracic aortic diameters were found to be typical among the aging population. These findings, from a prospective population-based study, were published in Heart.
Data for this analysis were sourced from the Rotterdam Study which was initiated in 1990. A random subset of 2524 participants received non-contrast computed tomography (CT) between 2003 and 2006. A second CT scan was performed between 2018 and 2020 among 943 of the original cohort. Longitudinal changes to thoracic aortic diameters were evaluated.
The participants with data at baseline and follow-up are median age 65.0 (IQR, 62.0-68.0) years, 52% are women, the mean body surface area is 1.9±0.2 m2, 53.5% have hypertension, 22.2% are taking lipid-lowering agents, and 19.1% are taking beta-blocking agents.
During an average of 14.1±0.3 years of follow-up, the diameters of the ascending aorta increased from 37.3 to 38.4 mm among men and 34.7 to 35.6 mm among women and the descending aorta increased from 29.6 to 30.6 mm and from 26.9 to 27.6 mm, respectively. Overall, the ascending aorta increased in diameter by 0.71 mm/decade and the descending aorta by 0.70 mm/decade. Men have greater absolute changes in ascending (median, 0.72 vs 0.70 mm/decade; P =.006) and descending (median, 0.71 vs 0.69 mm/decade; P =.008) aortic diameters.
The change in ascending and descending aortic diameters are correlated (r, 0.36; P <.001).
Overall, significant predictors for ascending aortic diameter changes are being a woman (β, -2.39; P <.001), body mass index (BMI; β, 0.13; P <.001), diastolic blood pressure (β, 0.06; P <.001), and age (β, 0.08; P =.013).
Stratified by gender, diastolic blood pressure (P <.001), age (P =.005), and BMI (P =.014) remain significant for women and only BMI (P =.012) remains significant for men.
For the descending aorta, being a woman (β, -2.45; P <.001), age (β, 0.13; P <.001), BMI (β, 0.16; P <.001), currently smoking (β, 0.67; P =.009), formerly smoking (β, 0.40; P =.017), diastolic blood pressure (β, 0.02; P =.030), and use of serum lipid reducing agents (β, -0.42; P =.033) are significant predictors of longitudinal change.
For women, age (P <.001), BMI (P <.001), diastolic blood pressure (P =.005), and currently smoking (P =.027) are significant predictors of descending aortic diameter change. For men, age (P <.001), BMI (P <.001), and use of serum lipid reducing agents (P =.025) predict descending aortic diameter changes.
This study may have been limited by the cohort of patients who survived and participated in the follow-up, as cohorts that were lost to follow-up differed for some baseline characteristics.
The study authors concluded that increases to thoracic aortic diameters was typical among all patients as they age. “Our data suggest that changes in absolute aortic diameters faster than 3 mm/decade should be considered abnormal,” the study authors wrote. “The possible positive effects of lipid-lowering medication and male-female-specific risk factors warrant further study.”
Thijssen CGE, Mutluer FO, van der Toorn JE, et al. Longitudinal changes of thoracic aortic diameters in the general population aged 55 years or older. Heart. Published online April 28, 2022. doi:10.1136/heartjnl-2021-320574