Prognostic Value of Vascular Calcifications and Regional Fat Depots Derived From Conventional Chest Computed Tomography

Abstract

Purpose: The prognostic value of vascular calcifications as well as of regional fat depots has been reported separately, in population-based studies, and using gated-computed tomography (CT) examinations. We, therefore, explored the interplay and prognostic value of vascular calcifications and adipose tissue depots assessed during conventional nongated chest CT. Materials and Methods: We enrolled a consecutive series of 1250 patients aged between 35 and 74 years who underwent clinically indicated chest CT scans. We measured the extent of coronary artery calcification (CAC) using the segment-involvement score (CACSIS), and aortic and valve calcification. Pericardial fat volume (PFV), hepatic fat, and abdominal subcutaneous adipose tissue were also calculated. Patients were followed-up for all-cause mortality. Results: A total of 577 (46%) patients had presence of CAC in the coronary tree. Over a mean follow-up of 3.7 years, 51 (4%) deaths occurred, 23 (4.1%) in male patients and 28 (4.1%) in female patients. Patients with higher PFV were older (P<0.0001), more frequently male (P<0.0001), had higher abdominal subcutaneous adipose tissue (P<0.0001), hepatic fat (P<0.0001), as well as a larger extent of CAC (P<0.0001), aortic calcium (P<0.0001), and valve calcium (P<0.0001). From a multivariable Cox regression model, age (hazard ratio [HR], 1.07; 95% confidence interval [CI], 1.03-1.11), P=0.001, PFV upper tertile (HR, 4.07; 95% CI, 2.09-7.92), P<0.0001, and CACSIS>5 (HR, 2.19; 95% CI, 1.14-4.23; P<0.0001) were independent predictors of all-cause death. Conclusions: In this relatively large patient cohort undergoing clinically indicated conventional chest CT scans, PFV and coronary calcification were high-risk markers associated with worsening survival.