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.