OBJECTIVE: Lipoprotein subclasses and high-density lipoprotein (HDL) functions are associated with atherosclerotic cardiovascular disease (ASCVD), but researches on them in patients with nephrotic syndrome (NS) are limited. The aims of this study were (1) to analyze the changes in quantity and quality of lipoprotein in patients with idiopathic nephrotic syndrome (INS) and patients in remission from NS, and (2) to evaluate the lipid-related atherosclerotic risk in these patients. METHODS: 51 patients with idiopathic nephrotic syndrome (NS group), 72 NS patients with complete remission (NS remission group), and 80 healthy controls (control group) were recruited. The levels of conventional lipids, lipoprotein subclasses, including VLDL, IDL (C, B, A), LDL (LDL1-7), HDL (large, intermediate, small) and HDL cholesterol efflux capacity (CEC), were measured and compared across the three groups. RESULTS: Conventional lipid parameters [TG, TC, LDL-C, apo-B and Lp(a)] and lipoprotein subclasses (VLDL, IDL-C, IDL-B, LDL-2 and sdLDL) were higher in NS group when compared to NS remission group and control group (P <
0.05). CEC in NS group was significantly lower than that in control group [21.0 (18.3-27.2) % vs 25.7 (23.3-28.9) %] (P <
0.001) and improved to 22.8 (20.6-23.7) % in NS remission group with the disease recovery. CONCLUSION: Proatherogenic changes in conventional lipid parameters, lipoprotein subclasses and HDL-CEC were observed in patients with NS, suggesting that more rigorous lipid regulation strategies may help reduce cardiovascular disease risk in patients with NS.