CLINICAL AND DIAGNOSTICAL SIGNIFICANCE OF ENDOTHELIAL DYSFUNCTION IN PATIENTS WITH CHRONIC KIDNEY DISEASE

Chronic kidney disease (CKD) represents a steadily growing global medical and socioeconomic burden, characterized by progressive and irreversible loss of renal function and a markedly increased risk of cardiovascular morbidity and mortality. Numerous large-scale epidemiological investigations have demonstrated that cardiovascular complications account for more than half of all deaths among patients with CKD, frequently occurring at early stages of renal dysfunction and often preceding the need for renal replacement therapy [1,2]. In recent decades, endothelial dysfunction has been identified as a central pathophysiological mechanism that links impaired renal function with accelerated atherosclerosis, arterial stiffness, vascular calcification, and adverse cardiovascular outcomes. The vascular endothelium is a highly specialized and metabolically active organ that plays a crucial role in maintaining vascular homeostasis by regulating vasomotor tone, inflammatory responses, oxidative balance, hemostasis, and smooth muscle cell proliferation. In the context of CKD, endothelial integrity is progressively disrupted by a complex interplay of uremic toxin accumulation, chronic low-grade inflammation, oxidative stress, dyslipidemia, anemia, and disturbances in calcium–phosphorus metabolism, leading to profound alterations in endothelial phenotype and function [3–6]. The present study was designed to provide a comprehensive evaluation of the clinical and diagnostic significance of endothelial dysfunction in patients with different stages of chronic kidney disease. This observational study was conducted at the Khorezm multidisciplinary medical center and included 120 patients stratified according to CKD stage. Endothelial function was assessed using flow-mediated dilation of the brachial artery, serum nitric oxide levels, endothelin-1 concentrations, and C-reactive protein as an inflammatory marker. The results demonstrated a clear and progressive deterioration of endothelial function with advancing CKD stage, with the most pronounced abnormalities observed in patients with end-stage renal disease undergoing maintenance hemodialysis. A strong correlation was identified between estimated glomerular filtration rate and endothelial dysfunction parameters, underscoring the close interrelationship between renal impairment and vascular endothelial injury. These findings support the concept that endothelial dysfunction is not merely a consequence but a key driver of cardiovascular pathology in CKD and highlight its potential value as an important clinical and diagnostic marker for cardiovascular risk stratification and therapeutic decision-making in this high-risk population.