Anticalcifying nanoparticle antibody titer is an independent risk factor for coronary artery calcification.

Background: Calcium phosphate deposition is present even in the early phases of the atherosclerotic plaque formation. Calcifying nanoparticles (CNPs), previously known as nanobacteria, have emerged as a potential causative agent for pathological calcification in human vasculature. This study investigates the relationship between the anti-CNPs antibody titers and the extent of coronary calcification.

Methods: A total of 197 consecutive patients undergoing multidetector computed tomography were enrolled in this study. The patients with coronary artery calcification (CAC; n=103) were included in the CAC group, and those without calcification (n=94) were determined as controls. The commercially available enzyme-linked immunosorbent assay kits were used to detect IgG antibodies against CNPs in serum samples.

Results: Mean titers of anti-CNPs antibodies were higher in individuals with CAC than in the control group (0.4 ± 0.4 vs. 0.19 ± 0.21U; P<0.0001). Multivariate logistic regression analysis revealed that high anti-CNPs antibody levels were an independent correlate of CAC in addition to conventional risk factors such as age, hypertension, diabetes mellitus, and low levels of high-density lipoprotein cholesterol. When the CAC scores were subcategorized: score 0, 1-100, 101-400, and more than 400, they still correlated significantly with the anti-CNPs antibody, especially in the group having CAC scores greater than 400 (P<0.0001).

Conclusion: Anti-CNPs antibodies are an independent risk factor for CAC and the antibody levels correlate with CAC scores.