[Relationship between serum free fatty acid and cytokines, carotid atherosclerosis in chronic kidney disease].

ABSTRACT

OBJECTIVE: To investigate the serum level of free fatty acid (FFA) and explore its relationship with cytokines and atherosclerosis (AS) in chronic kidney disease (CKD). METHODS: The serum level of FFA was determined with enzymatic colorimetry. IL-1ß, IL-6 and TNFα were determined with ELISA. High-sensitivity C-reactive protein (hsCRP) was measured with immunoturbidimetry. Prevalence of atherosclerosis was detected with carotid ultrasonography. We evaluated the relationship between serum levels of FFA and IL-1ß, IL-6, TNFα, hsCRP as well as the renal function in 130 adult patients with CKD, stratified according to the GFR (based on the National Kidney Foundation/Kidney Dialysis Outcomes Quality Initiatives) and in 58 hemodialytic (HD) patients. The relationship between FFA level and cardiac geometry incidence in CKD patients was analyzed with logistic regression model. RESULTS: The serum level of FFA was significantly higher in CKD patients as compared with that in the healthy controls [(492.63±143.59) vs (302.65±142.18) µmol/L, P<0.01], even in the early stage of CKD. The level of FFA increased with the progression of renal dysfunction. In the non-dialytic CKD group, the level of FFA was negatively related to GFR and positively related to the proteinuria (P<0.05), while in the HD group, it was positively correlated with dialysis duration (P<0.05). The serum levels of FFA were higher in CKD patients with carotid artery atherosclerosis than those in patients without (P<0.05or<0.01). However, in both groups with impairment of renal function, the levels of FFA were positively correlated with hsCRP, IL-1ß, IL-6, TNFα and TG (all P<0.05). A positive correlation between the level of FFA and the clinical manifestations such as carotid intimal medial thickness (IMT) and AS was also found. A negative correlation was found between the level of FFA and the serum level of albumin and GFR (P<0.05). CONCLUSION: Serum levels of FFA are significantly higher either in non-dialytic CKD or in HD patients and it is related with hsCRP, IL-1ß, IL-6, TNFα as well as carotid artery atherosclerosis, indicating that FFA is an independent risk factor of AS in CKD.