Interleukin-6 is associated with high-risk plaque on coronary computed tomography angiography in asymptomatic women

Abstract

Background: Coronary high-risk plaque (HRP) is associated with inflammation and adverse outcomes in symptomatic individuals with coronary artery disease (CAD), yet determinants of HRP in asymptomatic individuals without known CAD remain ambiguous.

Objectives: We examined the association between interleukin 6 (IL-6) levels and HRP in asymptomatic women without known CAD and hypothesized higher IL-6 levels will be associated with HRP.

Methods: We measured serum IL-6 levels and performed Coronary Computed Tomography Angiography (CCTA) in 77 women without known CAD enrolled in the Atlanta Women's Interagency HIV Study (median age 54, 92.2% Black, 67.5% living with HIV). Those with spotty calcification, napkin ring sign, low attenuation, or positive remodeling coronary plaque features on visual or semi-automated analyses were categorized as having HRP. We used logistic regression models adjusted for clinical and sociodemographic risk factors or the pooled cohort equation (PCE).

Results: The median PCE score was 5.4%, the median IL-6 level was 2.18 [1.33, 3.59] pg/mL, 51.9% had coronary plaque and 38.9% had HRP on CCTA. Women with IL-6 concentrations in the top quartile (IL-6 > 3.59 pg/mL) were more likely to have HRP than those in lower quartiles (63.2%¦vs. 31%, p=0.01). IL-6 levels were associated with HRP prevalence, independent of cardiovascular risk factors (OR [95% CI]: 1.43 [1.12, 1.92], p=0.008) or PCE score (OR: 1.36 [1.09, 1.77], p=0.01) or HIV status.

Conclusion: In asymptomatic, predominately Black women, IL-6 mediated inflammation is associated with a greater likelihood of the presence of HRP.

Keywords: High risk coronary plaque; Inflammation; Interleukin-6.

Fig. 1

Participant selection.

Fig. 2

Prevalence of HRP by IL-6 quartile.

Fig. 3

IL-6 concentrations by HRP status.

Fig. 4

Unadjusted and adjusted associations between IL-6 concentration and HRP prevalence.