High-sensitivity C-reactive protein and endothelin-1 in age-related macular degeneration

Background: Age-related macular degeneration (AMD) is the most common cause of elderly irreversible vision loss in the world. Since C-reactive protein (CRP) is a potential risk factor that has been known to induce AMD, this study was designed to explore the relationship between AMD and serum levels of high sensitrvity C-reactive protein (hsCRP), and endothelin-1 (ET-1). Methods: The subjects were 48 males with AMD (28 with wet type and 20 with dry type) having a mean age of 69.4 +/- 9.6 years and a matched group of 45 apparently healthy control subjects. The AMD was diagnosed using a slit-lamp with super filled lens, fundus photography and fluorescein angiography. Levels of hsC RP and ET-1 were determined using ELISA methods. Results: hsCRP (6.96 +/- 5.15 vs. 3.64 +/- 4.67 mg/l, P<0.0001) and ET-1 levels (0.66 +/- 0.31 vs. 0.52 +/- 0.25 pg/ml, P = 0.025) in the patients were higher than in the controls, but the multivariate analysis also showed a significant difference in cholesterol level (P <0.001). There were no significant differences in the serum levels of hsCRP and ET-1 between the two types of AMD (P>0.05). ET-1 also correlated directly with hsCRP levels (r = 0.284, P < 0.01). Conclusions: The results suggest that although the serum levels of ET-1 and hsCRP are higher in the patients with AMD, they are a dependent risk factor. (C) 2009 WPMH GmbH. Published by Elsevier Ireland Ltd.