Plasma vascular endothelial growth factor, soluble VEGF receptor FLT-1, and von Willebrand factor in glaucoma.

AIM: To investigate plasma indices of vascular permeability (vascular endothelial growth factor, VEGF-also an index of angiogenesis, as well as the soluble receptor for VEGF, sFlt-1) and endothelial damage/dysfunction (von Willebrand factor, vWf) in glaucoma.

METHODS

Citrated plasma was assayed for VEGF, sFlt-1, and vWf (all ELISA) in a cross sectional study of 50 patients (20 male; mean age 63.9 years, SD 10.5) with glaucoma: 26 had normal tension glaucoma (NTG) and 24 had primary open angle glaucoma (POAG), who were compared with 26 healthy controls (mean age 73.4 years, SD 9.2).

RESULTS

Median (interquartile range, IQR) levels of VEGF were significantly elevated in patients with NTG and POAG compared to healthy controls (Kruskal-Wallis test, p<0.001). Similarly, mean (SD) vWF levels were abnormal in NTG and POAG compared to healthy controls (one way ANOVA, p<0.001). Median levels of sFlt-1 were significantly lower in patients with NTG and POAG, when compared to healthy controls (Kruskal-Wallis test, p<0.001; p<0.05 with Tukey's post hoc test for controls v POAG). There were no significant differences in VEGF, sFlt-1 or vWf levels between the NTG and POAG groups (Tukey's test, all p=NS). In both NTG and POAG groups, there was a significant correlation between VEGF and sFlt-1 (Spearman, NTG: r=0.6517, p=0.001; POAG: r=0.6017, p=0.008). There were no significant correlations between VEGF and sFlt-1, or with vWf among the controls.

CONCLUSIONS

The pathogenesis of optic nerve damage in both NTG and POAG may be associated with abnormal vascular permeability and endothelial damage/dysfunction, as indicated by abnormal plasma VEGF and vWf levels in these patients.