Plasma concentration of ET-1 in patients with glaucoma with and without visual field progression (triangle = mean; box = standard error od the mean; whiskers = standard deviation). Plasma levels of ET-1 at the end of the observation period were significantly higher in patients with progressive damage (3.47 (0.75) pg/ml; range 2.34–5.17 pg/ ml) compared with those with stable (2.60 (SD 0.54) pg/ml; range 1.91–3.45 pg/ml) visual fields (ANOVA: ; ). This difference was still significant after controlling for the interaction of sex and including age and MBP as covariates into the model (ANCOVA: ; ). Sex had a borderline significant effect (ANCOVA: ; ), but the interaction between sex and disease progression was not significant (ANCOVA: ; ). Figure adapted from Emre et al. [52].
