Abstract

Chronic kidney disease (CKD) is associated with malnutrition-inflammation-atherosclerosis (MIA) syndrome—persistent inflammation and protein-energy wasting, both of which adversely affect nutritional status and quality of life. High-sensitivity C-reactive protein (hs-CRP) is a well-established marker of systemic inflammation, while circulating microRNA-223 (miR-223), an epigenetic biomarker, is a new frontier in the immune and inflammatory regulation of renal fibrosis in CKD. Therefore, we conducted this study to primarily investigate the associations between systemic inflammatory activity (assessed by hs-CRP), circulating levels of immunoregulatory miR-223, and nutritional status (evaluated by the Subjective Global Assessment, SGA) in end-stage kidney disease (ESKD) patients undergoing different renal replacement therapy modalities— hemodialysis (HD), hemodiafiltration (HDF), and kidney transplantation. A secondary objective was to explore how these immune inflammatory profiles differ across modalities and their potential impact on functional and nutritional outcomes. This cross sectional observational study included 75 ESKD adult patients recruited consecutively: 25 on HD, 25 on HDF and 25 kidney transplant recipients. A total of ten healthy volunteers were included as a reference group for miR-223 expression. ELISA measured hs-CRP levels, and miR-223 expression was quantified using real-time PCR and reported as relative expression levels using the 2^-ΔCt method. Nutritional status was assessed using the SGA score. Group comparisons and correlation analyses were performed. hs-CRP levels were significantly higher in HD patients (median 14.2 mg/L) compared with HDF (6.3 mg/L) and kidney transplant recipients (5.2 mg/L)(p = 0.003).miR-223 expression was significantly downregulated in both dialysis groups compared with kidney transplant recipients (p < 0.001), with post-transplant levels approaching those of healthy controls. Nutritional status differed significantly among groups (p < 0.001): 100% of kidney transplant recipients were classified as SGA Class A (well nourished) compared with 76% in the HDF group and 32% in the HD group. In conclusions, Kidney transplantation is associated with lower inflammatory burden and better nutritional status than dialysis modalities. Reduced miR-223 in dialysis patients and its improvement after transplantation suggest a potential association with inflammatory and nutritional status in ESKD. This could be clinically relevant with potential implications for understanding the epigenetic regulation of inflammation in ESKD. Further longitudinal studies are needed to clarify causal relationships and to better understand the role of miR-223 in CKD pathophysiology (Protective role).

Keywords: CKD; ESKD; HD; HDF; hs-CRP; Inflammation; Kidney transplantation; miR-223; Nutritional status; Subjective Global Assessment.

Date received: 07 February 2026; accepted: 19 March 2026

PMID:
41966631