OBJECTIVE: The aim of this study was to evaluate the association of the calcification regulators, osteopontin (OPN) and osteoprotegerin (OPG),which are involved in vascular calcification and atherosclerosis in patients with peripheral arterial disease (PAD).METHODS: A Pubmed search of the English language literature was undertaken to identify articles that examine the role of the vascular calcification markers (OPN and OPG) in patients with PAD. The search retrieved 94 articles. After excluding non-relevant articles, only 11 studies qualified for review.RESULTS: In 8 studies, OPG levels were correlated with the presence, severity, and progression of PAD, whereas in one article, OPG levels were not significantly elevated. In2 studies, OPN levels were associated with PAD and vascular stiffness.CONCLUSION: The results from clinical and experimental research regarding the role of vascular calcification markers in PAD are controversial, although most of the studies suggest a positive correlation. Larger studies are needed to determine the exact pathway of vascular calcification, mediated by calcification markers, in patients with PAD.