Retinal Vascular Imaging Markers and Incident Chronic Kidney Disease: A Prospective Cohort Study

Abstract

Retinal microvascular changes indicating microvascular dysfunction have been shown to be associated with chronic kidney disease (CKD) in cross-sectional studies, but findings were mixed in prospective studies. We aimed to evaluate the relationship between retinal microvascular parameters and incident CKD in an Asian population. We examined 1256 Malay adults aged 40-80 years from the Singapore Malay Eye Study, who attended both the baseline (2004-07) and the follow-up (2011-13) examinations and were free of prevalent CKD. We measured quantitative retinal vascular parameters (arteriolar and venular calibre, tortuosity, fractal dimension and branching angle) using a computer-assisted program (Singapore I Vessel Assessment, SIVA) and retinopathy (qualitative parameter) using the modified Airlie house classification system from baseline retinal photographs. Incident CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 + 25% decrease in eGFR during follow-up. Over a median follow-up period of 6 years, 78 (6.21%) developed CKD (70.5% had diabetes). In multivariable models, smaller retinal arterioles (hazards ratio [95% confidence interval] = 1.34 [1.00-1.78]), larger retinal venules (2.35 [1.12-5.94] and presence of retinopathy (2.54 [1.48-4.36]) were associated with incident CKD. Our findings suggest that retinal microvascular abnormalities may reflect subclinical renal microvascular abnormalities involved in the development of CKD.