Association between perivascular fat density on CT angiography and abdominal aortic aneurysm progression.

Background: Perivascular adipose tissue has been shown to play a role in cardiovascular disease. This provides evidences that perivascular fat density (PFD) may have a correlation with abdominal aortic aneurysm (AAA). The aim of study was to investigate the association between PFD on computed tomography angiography (CTA) and AAA expanding rate.

Methods: A total of 144 patients with AAA who underwent at least two computed tomography angiography (CTA) examinations at intervals of ≥ 6 months between January 2014 and June 2023 were included. The patients were divided into slowly and rapidly expanding AAA groups according to the median value of AAA expansion rate. The clinical and CTA characteristics of both groups were compared. The relationships between AAA diameter, AAA volume, expansion rate, and PFD were tested using the pearson coefficient.

Results: Compared with the slowly expanding group, patients with rapidly expanding AAA had a significantly higher prevalence of hypertension (77.8% versus 55.6%; P = 0.005), a significantly lower prevalence of diabetes (26.4% versus 47.2%; P < 0.010), and a higher PFD at baseline (-72.6 ± 9.7 HU vs. -81.2 ± 7.9 HU; P < 0.001). In the whole group, slowly expanding group, and rapidly expanding group, PFD at baseline was positively correlated with AAA diameter at baseline (P < 0.001), AAA volume at baseline (P < 0.001), and expansion rate (P < 0.001). A positive correlation was observed between increasing PFD and expansion rate (P < 0.05).

Conclusions: A higher PFD on CTA was found to be related to a rapidly expanding AAA. Thus, PFD may become a non-invasive and potential image marker for predicting and treating AAA progression.

Clinical trial number: Not applicable. This research is a retrospective analysis.