Association of chorioretinal thickness with chronic kidney disease

OBJECTIVE: To assess retinal and choroidal thickness changes in chronic kidney disease (CKD) patients using spectral domain optical coherence tomography (SD-OCT). BACKGROUND: CKD is a devastating health trouble. The eye and the kidney share similar structural and genetic pathways, so that kidney disease and ocular disease may be closely linked. OCT is a precise, fast method for high-definition scanning of the retina and choroid. PATIENTS AND METHODS: A cross sectional study was conducted at Menoufia University Hospital ophthalmology department on 144 eyes of 72 CKD patients divided into 3 groups according to the stage of CKD as follows: group 1: CKD stage 1–2, with Glomerular Filtration Rate (GFR) > 60 ml/min/1.73m(2) group 2: CKD stage 3, GFR 30–59 ml/min/1.73m(2) and group 3: CKD stage 4–5, eGFR < 29 ml/min/1.73m(2). All patients underwent full ophthalmologic examination followed by OCT assessment of retinal, retinal nerve fiber layer (RNFL) and choroidal thickness. RESULTS: Retinal and choroidal thickness were reduced in group 2 (CKD stage 3) and group 3 (CKD stage 4–5) compared with group 1 (CKD stage 1–2). The reduction was more severe in group 3 than group 2. RNFL thickness did not differ between groups. A thinner retina and choroid were associated with an elevated serum C-reactive protein (CRP) concentration, and greater degrees of proteinuria. CONCLUSION: Chorioretinal thinning in CKD is associated with a lower eGFR, a higher CRP, and greater proteinuria. Further studies, in a large scale of patients, are needed to detect whether these eye changes reflect the natural history of CKD.