The plasma OPG concentrations were significantly increased in patients with carotid arterial disease and PAD compared to patients without (1.28 (0.99-1.61) versus 1.04 (0.80-1.33) μg/l, p < 0.001 and 1.47 (1.02-1.89) versus 1.08 (0.85-1.40) μg/l, p < 0.001, respectively) (Table 2 and Figure 1). The gene discussed is TNFRSF11B; the disease is peripheral arterial disease.