Non-obstructive coronary artery disease (NOCAD) is a condition in stable patients that experience angina despite not having significant coronary obstructive lesion. Knowledge on the role of certain biomarkers in patients with NOCAD is still limited. This study aimed to evaluate the roles of inflammation and adhesion molecules in the development of NOCAD. The correlations between the peripheral and coronary levels of the inflammatory biomarkers and adhesion molecules were also investigated.

Elevated levels of the hsCRP, GDF-15, and VCAM-1 were found with NOCAD, despite the absent of significant coronary obstruction. VCAM-1 successfully predicted NOCAD and may thus serve as an early NOCAD biomarker. Significant correlations of hsCRP, GDF-15, and VCAM-1 level in peripheral and coronary blood indicate that the peripheral levels of these biomarkers reflect the levels and changes that occur at the coronary level.

In this cross-sectional study, symptomatic angina patients scheduled for coronary angiograms were recruited and separated into obstructive coronary artery disease (OCAD) and NOCAD groups based on those angiograms. Peripheral and coronary blood samples were taken to measure inflammation biomarkers [high sensitivity C-reactive protein (hsCRP) and growth differentiation factor 15 (GDF-15)], and adhesion molecules [vascular cell adhesion molecule-1 (VCAM-1)]. Subjects without angina symptoms were recruited for the control group.

The hsCRP, GDF-15, and VCAM-1 levels were higher in the OCAD and NOCAD groups than in the control group. VCAM-1 levels successfully predicted the incidence of NOCAD [p = 0.010, area under the curve (AUC) = 0.716]. All biomarkers' levels in the peripheral and coronary blood were correlated in OCAD and NOCAD patients (p < 0.001).