Prognostic effect of changes in high-density lipoprotein cholesterol after kidney transplantation.

High-density lipoprotein cholesterol (HDL-C) is inversely associated with cardiovascular diseases and may protect kidney function. This study evaluated the impact of early post-transplant HDL-C changes on clinical outcomes in kidney transplant recipients (KTRs). A total of 4,446 KTRs were classified into four groups according to HDL-C levels before transplantation and at 6 months post-transplant: low-low, low-normal, normal-low, and normal-normal. The primary outcome was a composite of cardiovascular events and graft failure. KTRs with persistently normal HDL-C levels had the lowest incidence of the composite outcome. Cox regression analysis revealed that persistent low HDL-C levels, improvement from low to normal HDL-C levels, and a decline from normal to low HDL-C levels showed an increased risk of the composite outcome compared to persistent normal HDL-C levels (HR, 1.48, 95% CI, 1.09-2.02, P=0.013; HR, 1.41, 95% CI, 1.10-1.80, P=0.006; and HR, 2.09, 95% CI, 1.35-3.24, P=0.001, respectively). Persistently low HDL-C levels and low-to-normal HDL-C changes were mainly associated with cardiovascular events, whereas post-transplant HDL-C decline was more strongly linked to graft failure. Abnormal HDL-C trajectories after kidney transplantation were significantly associated with unfavorable long-term cardiovascular and graft outcomes, highlighting the prognostic importance of both pre- and post-transplant HDL-C status.