Apolipoproteins in Chronic Kidney Disease and Kidney Transplant: A Long Unfinished Story

Chronic kidney disease (CKD) is a growing global health burden, strongly associated with cardiovascular disease, the leading cause of mortality in this population. Dyslipidemia is a key metabolic abnormality in CKD, but traditional lipid measures such as total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides often fail to capture the complexity of lipid disturbances in CKD and after kidney transplantation. Apolipoproteins have emerged as more reliable markers of cardiovascular and renal risk. Elevated apolipoprotein B (ApoB), reduced apolipoprotein A1 (ApoA1), and a higher ApoB/ApoA1 ratio are linked to CKD progression, cardiovascular events, and post-transplant complications, including post-transplant diabetes mellitus. Lipoprotein(a), a genetically determined atherogenic lipoprotein, accumulates in CKD due to impaired clearance and further increases cardiovascular risk. Other apolipoproteins, such as APOL1 and APOE, modulate CKD susceptibility through lipid-dependent and independent mechanisms. In addition, proprotein convertase subtilisin/kexin type 9 (PCSK9) has been identified as an important regulator of lipid metabolism, and PCSK9 inhibitors may represent a promising therapeutic option, though evidence in advanced CKD and transplant recipients is still limited, especially regarding their effects on apolipoproteins. This review summarizes current evidence on apolipoproteins and PCSK9 in CKD and transplantation, with attention to their potential as biomarkers and therapeutic targets.