Association of aortic perivascular adipose tissue density with aortic calcification in women with systemic lupus erythematosus

Abstract

Background and aims: Women with systemic lupus erythematosus (SLE) have an increased risk of cardiovascular disease (CVD). Perivascular adipose tissue (PVAT) surrounds the vascular wall, is associated with CVD risk factors, and may contribute to premature CVD in SLE. We previously found greater volumes of aortic PVAT associated with aortic calcification (AC) in female SLE patients. There is recent evidence that not only volume but adipose density may also be indicative of inflammation. We hypothesized that female SLE patients would have a difference in aPVAT quality associated with AC that is independent of volume.

Methods: Aorta PVAT quality was evaluated using the average radiodensity (density) of adipose tissue-specific Hounsfield Units (-190 to -30 HU) within each clinical CT scan of CVD-free, age-/race-matched SLE women (n = 143) and healthy controls (HC, n = 143).

Results: Aorta PVAT density was significantly higher in SLE (mean (SD): (-83.6 (1.9) HU) versus HC (-84.1 (1.8) HU), p=0.03). Increasing aPVAT volume was correlated with denser aPVAT in SLE (ρ, p-value: 0.75,<0.0001) and HC (0.74,<0.0001). Increasing AC score (log) was correlated with denser aPVAT for SLE (0.31, 0.0005) and HC (0.23, 0.008). In linear regression, denser aPVAT was more strongly associated with AC score in SLE (β (SE): 0.445 (0.11), p<0.0001) versus HC (0.335 (0.12), p=0.006) independent of age, circulating inflammatory markers, CVD risk factors and BMI (p<0.05), but was attenuated with aPVAT volume (p=0.3).

Conclusions: Denser aPVAT is associated with aPVAT volume and AC in SLE women. Adjusting for aPVAT volume attenuated the detected association between aPVAT density and AC, which may be indicative of adipose dysfunction.

Keywords: Adipose quality; Computerized tomography; Epidemiology; Perivascular adipose tissue; Subclinical cardiovascular disease; Vascular calcification; Women.