Renal glomerular dysfunction in relation to retinal arteriolar narrowing and high pulse pressure in seniors

Retinal arteriolar narrowing and high pulse pressure (PP) are associated with macrovascular complications and microvascular renal disease. Few studies addressed whether in seniors (>= 60 years) estimated glomerular filtration rate (eGFR) is independently related to central retinal arteriolar equivalent (CRAE) and PP. In 292 randomly recruited seniors (49.3% women; mean, 68.2 years), we measured PP by standard sphygmomanometry, CRAE (IVAN software), eGFR (Chronic Kidney Disease Epidemiology Collaboration equation) and stage of chronic kidney disease (CKD (Kidney Disease Outcomes Quality Initiative guideline)). Statistical methods included linear and logistic regression. PP, CRAE and eGFR averaged 59.2 mm Hg, 146.3 mu m and 79.9 ml min(-1) per 1.73 m(2). Decline in eGFR (-2.27 ml min(-1) per 1.73m(2) per 15 mu m; P = 0.011) occurred in parallel with CRAE narrowing. CRAE (effect size per 1-s.d. increment, -1.85 mu m; P = 0.032) and eGFR (-2.68 ml min(-1) per 1.73m(2); P = 0.003) both declined with higher PP. With PP increasing from 63 to 73 mm Hg (threshold for macrovascular complications), CRAE dropped by -4.70 mu m (P <= 0.037). A 70-mm Hg PP threshold corresponded with a 150-mu m CRAE cutoff. The risk of CKD (stage >= 2 vs. 1; n = 203 vs. 89) rose with CRAE <150 mu m (odds ratio, 2.81; P<0.0001), but not with PP >= 70 mm Hg (1.47; P = 0.20). Additionally, CRAE added to PP increased the area under the curve from 0.58 to 0.64 (P = 0.047) for identifying stage >= 2 CKD. In seniors, CRAE and eGFR decline in parallel with higher PP. CRAE <150 mu m identifies early decline in eGFR.