Associations between inflammatory markers and carotid plaques in CKD: mediating effects of eGFR-a cross-sectional study

Background: Chronic kidney disease (CKD) is a significant public health concern associated with a high prevalence of carotid plaques, which are indicators of atherosclerosis and predictors of adverse cardiovascular outcomes. Inflammation is a hallmark of CKD, contributing to both renal dysfunction and cardiovascular complications. This study aims to investigate the association between inflammatory markers-systemic inflammatory response index (SIRI), systemic immune-inflammation index (SII), aggregate inflammatory status index (AISI), monocyte to high-density lipoprotein cholesterol ratio (MHR), neutrophil to high-density lipoprotein cholesterol ratio (NHR), neutrophil to lymphocyte ratio (NLR), and monocyte to lymphocyte ratio (MLR)-and carotid plaques in CKD patients, and to explore the potential mediating role of estimated glomerular filtration rate (eGFR) in this relationship.

Methods: A cross-sectional analysis was conducted on patients admitted to the Division of Nephrology between January 2023 and June 2023. The primary endpoint was the presence of carotid plaques assessed using ultrasound imaging. Multivariable logistic regression models were used to examine the associations between inflammatory markers and carotid plaques, and trend tests were performed to evaluate the trending association of carotid plaques risk and inflammatory markers in tertiles. Restricted cubic spline (RCS) analysis was used to assess potential non-linear relationships, and subgroup analyses were conducted to examine consistency across different strata. Mediation analysis was performed to explore the role of eGFR.

Results: Of the 609 participants, 387 were included in the final analysis after applying exclusion criteria. Elevated levels of LnSIRI (OR = 1.87, 95% CI = 1.25-2.80), LnSII (OR = 1.67, 95% CI = 1.09-2.56), LnAISI (OR = 1.70, 95% CI = 1.22-2.37), LnMHR (OR = 1.94, 95% CI = 1.15-3.26), LnNHR (OR = 1.82, 95% CI = 1.10-3.02), and LnMLR (OR = 2.26, 95% CI = 1.18-4.34) were significantly associated with the presence of carotid plaques. There were significant trends for increasing tertiles of SIRI, AISI, MHR and NHR. RCS analysis showed no significant non-linear associations. Subgroup analyses indicated similar associations across most strata. eGFR partially mediated these relationships, with proportions mediated ranging from 14.7 to 17.5%.

Conclusions: Inflammatory markers are significantly associated with carotid plaques in CKD patients, with eGFR playing a partial mediating role. These findings highlighted the importance of managing inflammation and maintaining renal function to mitigate the risk of atherosclerosis in CKD patients.

Trial registration: Not applicable.