β2-microglobulin, a novel biomarker of peripheral arterial disease, independently predicts aortic stiffness in these patients

Abstract

Arterial stiffness is a prominent feature of vascular ageing and strongly predicts cardiovascular and total mortality. The β2-microglobulin, (β2M) a newly identified biomarker of peripheral arterial disease (PAD), is related to renal insufficiency, inflammatory and neoplastic diseases, but may also play a role in vascular dysfunction. However, the relationship between arterial stiffness and β2M has not been previously studied in patients with atherosclerosis. In the present study we examined a possible association between β2M and arterial stiffness in patients with PAD and in healthy subjects. Plasma β2M levels and parameters of arterial stiffness such as aortic pulse wave velocity (aPWV) and augmentation index (AIx) were measured in 66 patients with PAD and in 66 apparently healthy subjects. Plasma levels of β2M, aPWV and AIx were significantly increased in patients with PAD compared with controls (1858.1 ± 472.8 vs 1554.5 ± 277.9 μg/L, p < 0.001; 9.9 ± 2.2 m/s vs 7.6 ± 1.6 m/s, p < 0.001; 28 ± 8 vs 14 ± 11%, p < 0.001; respectively). There existed significant correlation between aPWV and β2M for the patient group (R = 0.47; p < 0.001), but not for the controls (R = 0.14; p = 0.26). In multivariate analysis, β2M remained independently associated with aPWV, fetuin-A, age and glomerular filtration rate in patients (R² = 0.5, p < 0.001). We found no relationship between β2M and AIx in either group. We demonstrated that among patients with PAD elevated plasma β2M levels were associated with higher aortic stiffness irrespective of cardiovascular disease risk factors. These data suggest that β2M may influence the pathogenesis of aortic stiffness in atherosclerosis.

Key Words::

• Aortic pulse wave velocity
• atherosclerosis
• β2-microglobulin
• peripheral arterial disease

Acknowledgments

The authors are indebted to Ms Ester Jaigma for the linguistic revision of the text and to Mr Mart Kals for assistance in the statistical analysis. The current study was supported by grants of the Estonian Science Foundation (Nos. 7480, 6588 and 7395) and by the European Union through the European Regional Development Fund and by targeted financing from the Ministry of Education and Science of Estonia (No. 0180105s08).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.