Increased soluble urokinase plasminogen activator receptor (suPAR) levels in neovascular age-related macular degeneration: a role for inflammation in the pathogenesis of the disease?

To evaluate the plasma concentration of the soluble form of the urokinase-type plasminogen activator receptor ((s)uPAR), an established biomarker of chronic inflammation, in patients affected by neovascular age-related macular degeneration. Forty consecutive patients affected by age-related macular degeneration and 52 subjects with no history of the disease were included in this case–control study. The two groups of individuals considered for the study were matched for age, sex, and class of medications taken. Plasma concentration of suPAR was measured using a specific ELISA assay (suPARnostic, Birkeroed, Denmark). The case and control groups were similar for age, gender distribution, weight, height, and systolic and diastolic blood pressure, as well as for dyslipidemia and high blood pressure medication (P > 0.28). The plasma concentrations of suPAR were significantly increased in patients with neovascular age-related macular degeneration when compared to controls (6.19 ± 2.2 ng/ml, vs 5.21 ± 1.5, respectively, mean ± SD P = 0.01). Patients with neovascular age-related macular degeneration display increased plasma levels of suPAR, suggesting that chronic inflammation may be involved in the pathogenesis of the disease.