Soluble TWEAK may predict carotid atherosclerosis in treated HIV infection

Background: Soluble Tumor Necrosis Factor Weak Inducer of Apoptosis (sTWEAK) has been proposed as a novel biomarker of cardiovascular disease risk. This study compares levels of sTWEAK, sCD163 and the sCD163/sTWEAK ratio in HIV-infected and uninfected patients and their associations with cardiovascular and inflammatory factors. Methods: The data for our analysis come from 274 HIV-infected adults and 59 controls. HIV participants were on stable antiretroviral therapy (ART). Wilcoxon-Mann-Whitney tests were used for comparing markers between HIV-infected participants with HIV viral load < 50 copies/mL (aviremic group), HIV-infected participants with detectable viremia (HIV-1 RNA >= 50 copies/mL; viremic group) and HIV negative participants. Multivariable quantile regression analyses were used to assess associations of sTWEAK and sCD163 with other markers of inflammation and carotid intima-media thickness (cIMT). Results: Overall, 74% of participants were male; 59% were African-Americans; median age was 40years and CD4 595 cells/mm3. Overall, HIV-infected participants had reduced sTWEAK and increased sCD163 levels compared to HIV-uninfected participants (p=0.0001 for both markers). In addition, these biomarkers were significantly different between HIV-infected viremic and aviremic patients (p <= 0.01 for both markers). In multivariable models, sTWEAK and sCD163 in aviremic patients were significantly correlated with common carotid artery IMT (p <= 0.05). In HIV-infected aviremic participants, sTWEAK and sCD163 were both associated with IL-6, CD14+CD16+monocytes (p <= 0.02); additionally, sCD163 was associated with D-dimer- (beta=-69.5, 0.05), VCAM (beta=72.4, p < 0.05), TNF RI (beta=91.1, p < 0.01), and TNF RII (beta=87.8, p < 0.01). Conclusions: HIV-infected participants showed increased systemic inflammatory and monocyte activation markers. Soluble CD163 and sTWEAK levels were associated with carotid intima-media thickness.