Looking into the Eyes to See the Heart of Chronic Kidney Disease Patients

In patients with chronic kidney disease (CKD), the main cause of morbidity and mortality is cardiovascular disease (CVD). Both coronary artery calcium scoring by computed tomography (CT) and optical coherence tomography (OCT) are used to identify patients at increased risk for ischemic heart disease, thereby indicating a higher cardiovascular risk profile. Our study aimed to investigate the utility of these techniques in the CKD population. In patients with CKD, OCT was used to measure the choroidal thickness (CHT) and the thickness of the peripapillary retinal nerve fiber layer (pRNFL). A total of 127 patients were included, including 70 men (55%) with an estimated glomerular filtration rate (eGFR) of 39 ± 30 mL/min/1.73 m². Lower pRNFL thickness was found to be related to high-sensitivity troponin I (r = -0.362, p < 0.001) and total coronary calcification (r = -0.194, p = 0.032). In a multivariate analysis, pRNFL measurements remained associated with age (β = -0.189; -0.739--0.027; p = 0.035) and high-sensitivity troponin I (β = -0.301; -0.259--0.071; p < 0.001). Severe coronary calcification (Agatston score ≥ 400 HU) was related to a worse eGFR (p = 0.008), a higher grade of CKD (p = 0.036), and a thinner pRNFL (p = 0.011). The ROC curve confirmed that the pRNFL measurement could determine the patients with an Agatston score of ≥400 HU (AUC 0.638; 95% CI 0.525-0.750; p = 0.015). Our study concludes that measurement of pRNFL thickness using OCT is related to the markers associated with ischemic heart disease, such as coronary calcification and high-sensitivity troponin I, in the CKD population.