Effect of Systemic Hypertension and Dyslipidemia on the Relationship Between Serum Prorenin and Retinal Blood Flow in Type 2 Diabetes Patients

Abstract

Purpose: : To examine the effect of systemic hypertension (HT) and dyslipidemia (DL) on the relationship between serum prorenin and retinal circulation in patients with type 2 diabetes mellitus with systemic HT and DL.

Methods: : One hundred forty-four patients with diabetes (59.1±10.7 years) (mean±SD) and 45 control subjects (61.0±10.0 years) were enrolled in this study. The patients with diabetes had no diabetic retinopathy (DR) (n=101) or background DR (n=43) and were divided into four groups: diabetes without DL and HT (DM only group, n=43), diabetes with DL (DL group, n=27), diabetes with HT (HT group, n=28), and diabetes with DL and HT (DL+HT group, n=46). The serum prorenin levels of all subjects were measured using the antibody activating direct kinetic assay. The retinal circulation, which includes retinal vessel diameter and blood velocity that are used to calculate the retinal blood flow, was measured by using a laser Doppler velocimetry system (CLBF Model 100; Canon, Tokyo, Japan). The serum prorenin levels and retinal circulation were compared among the groups.

Results: : The serum prorenin levels in the HT (p<0.05) and DL+HT groups (p<0.01) were significantly higher compared with the control group. The serum prorenin level were significantly correlated with the retinal vessel velocity only in the DL+HT group (p=0.0093, r=-0.3754).

Conclusions: : Our results showed an increased serum prorenin level in patients with type 2 diabetes and HT. The serum prorenin level was negatively correlated with vessel velocity in the DL+HT group, suggesting that serum prorenin may be associated with impaired retinal circulation in patients with type 2 diabetes with systemic risk factors of HT and DL, especially in early-phase DR.

Keywords: diabetic retinopathy • clinical (human) or epidemiologic studies: risk factor assessment • flow cytometry