Pericoronary adipose tissue attenuation in low-risk asymptomatic individuals, sex-differences and association with markers of cardiovascular disease
Authors: Shanmuganathan N , Ramanathan R , Dey D , Goeller M , Kusk MW , Sidelmann JJ , Norgaard BL , Gram JB , Sand NPR 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Pericoronary adipose tissue (PCAT) attenuation by coronary computed tomography angiography (CCTA) is a marker of coronary inflammation and predicts clinical outcomes in symptomatic patients undergoing CCTA. Sex-differences in PCAT CT attenuation among asymptomatic individuals are not previously described.

Purpose
To evaluate PCAT CT attenuation according to sex and markers of cardiovascular disease (CVD).

Methods
Cross-sectional cohort study including asymptomatic individuals, 50- or 60-year of age, not taking any medicine and without known CVD or type-2 diabetes. At baseline and 5-year follow-up smoking habits, blood pressures and biochemistry (lipids, CRP, fibrinogen, D-dimer, t-PA, PAI-1, vWF) were recorded and Agatston Score measured. At follow-up, CCTA was achieved. Quantitative coronary plaque analysis was performed and PCAT CT attenuation within a radial distance of 3 mm from the outer vessel wall 10–50 mm distal to the origin of the right coronary artery measured. A validated PCAT CT attenuation threshold (high vs low risk) of -70.1 Hounsfield units was applied.

Results
Included were 123 participants (60 women). Independent of co-variation, PCAT CT attenuation (median, [IQR]) was lower in women (-71.0, [-77.2- -67.0]) vs men (-64.5, [-69.9- -57.4]), p &lt; 0.001. No associations between PCAT CT attenuation (high vs low) and risk factors of CVD, CAC or coronary plaque volumes were demonstrated (Table). Variations in blood pressures, biochemical markers and CAC over five years were not associated with PCAT CT attenuation.

Conclusion
In low-risk asymptomatic individuals, PCAT CT attenuation was lower in women compared to men, irrespective of markers of CVD.
Table. Patient characteristics stratified by PCAT CT attenuation PCAT CT attenuation ≤ -70.1 HU (n = 49) PCAT CT attenuation &gt; -70.1 HU (n = 74) p-value Risk factors Age65-years55-years 2623 3143 0.32 SexMenWomen 1534 4826 &lt;0.001 TobaccoNeverCurrent/previous 1732 3737 0.10 Systolic BP, mmHgDiastolic BP, mmHgTotal cholesterol, mmol/lLDL-cholesterol, mmol/lHDL-cholesterol, mmol/lTriglycerides, mmol/l 137 (17)76 (10)5.61 (0.92)3.50 (0.93)1.41 (0.30)1.65 (0.99 - 2.22) 136 (16)77 (10)5.42 (0.82)3.30 (0.82)1.45 (0.35)1.35 (1.03 - 2.11) 0.660.590.230.220.570.52 Biochemistry CRP, mg/lFibrinogen, μmol/lD-dimer, mg/lvWFt-PAPAI-1 1.16 (0.99 - 2.22)9.5 (8.5 - 10.7)0.40 (0.30 - 0.49)128 (102 - 154)7.1 (5.8 - 8.8)20.5 (16.2 - 31.8) 0.61 (0.30 - 1.14)9.0 (7.8 - 10.0)0.32 (0.24 - 0.47)116 (92 - 146)6.3 (5.1 - 8.8)20.3 (14.7 - 26.3) &lt;0.010.10&lt;0.050.110.200.34 Coronary plaque data Agatston ScoreTotal plaque volume, mm&sup3;NCP volume, mm&sup3;CP volume, mm&sup3;LD-NCP volume, mm&sup3; 1 (0 - 36)15.7 (0 - 143.3)0 (0 - 128.1)0 (0 - 14.6)0.5 (0 - 18.7) 8 (0 - 115)15.6 (0 - 268.2)13.5 (0 - 220.5)1.7 (0 - 31.7)1.8 (0 - 21.8) 0.300.450.490.360.74 Values are n (%), mean (SD) or median (IQR).Abbreviations: HU =Hounsfield unit; LDL =low-density lipoprotein; HDL =high-density lipoprotein; BP =blood pressure; CRP = c-reactive protein: vWF =von-Willebrand Factor; t-PA =tissue plasminogen activator; PAI-1 =plasminogen activator inhibitor -1; NCP =non-calcified plaque; CP =calcified plaque; LD-NCP =low-density non-calcified plaque.