REN and open-angle glaucoma: Both AH renin activity and renin activity AH-serum ratio were significantly lower inpatients with cataract and POAG than in patients with cataract only [(mean ±SE): 0.018 ± 0.006 ng/ml/h versus 0.045 ± 0.009 ng/ml/h, p<0.001;0.05 ± 0.02 versus 0.13 ± 0.05, p=0.025] (Figure 1).