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

Abstract 

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 sensitivity 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 hsCRP and ET-1 were determined using ELISA methods.

Results

hsCRP (6.96±5.15 vs. 3.64±4.67mg/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.

Keywords: Age-related macular degeneration (AMD), Endothelin-1 (ET-1), High-sensitivity C-reactive protein (hsCRP)