Calcium score of the entire thoracic aorta is an independent predictor of all-cause mortality in patients referred to chest computed tomography.

Background: Thoracic arterial calcifications (TAC) are not routinely reported or quantified in chest CT scans. We aimed to evaluate the association between TAC of the entire thoracic aorta and all-cause mortality (ACM) in patients referred to standard chest CT.

Methods: A retrospective analysis of consecutive standard chest CT scans (non-gated, non-contrast) for the quantification of TAC, CAC and aortic valve calcification. TAC was divided into 4 sample-derived categories (TAC 1 = 0, TAC 2 = 1-65, TAC 3 = 66-439 and TAC 4 ≥ 440). Data regarding ACM was retrieved from the health care provider database. Multivariate Cox proportional regression models were used to assess associations between the TAC categories and ACM.

Results: The study cohort included 415 patients (mean age 67 years, 52% male); 107 ACM events were recorded during a median follow-up of 9 years (inter-quartile range: 7.4-10.4). The rate of ACM was 13%, 25%, 32%, 41% according to TAC category (p < 0.001). The highest TAC category (≥ 440) was a strong and independent predictor of ACM [HR = 1.69 (1.13-2.52; 0.01)] in multivariate analysis. Other independent predictors of ACM included age [HR = 1.07 (1.04-1.10; p < 0.001)], male sex [HR = 2.27 (1.49-3.46; 0.001)] and malignancy [HR = 2.21 (1.49-3.23; < 0.001)].

Conclusions: Severe TAC (≥ 440) was found to be an independent predictor of ACM. Thus, we suggest that documenting and quantifying TAC should be routinely incorporated into standard chest CT reports.