Low HDL-Cholesterol Concentrations in Lung Transplant Candidates are Strongly Associated With One-Year Mortality After Lung Transplantation

Abstract

High-density lipoproteins (HDLs), whose main role is the reverse transport of cholesterol, also have pleiotropic anti-inflammatory, antioxidant, anti-apoptotic and anti-infectious properties. During sepsis, HDL cholesterol (HDL-C) concentration is low, HDL particle functionality is altered, and these modifications are correlated with poor outcomes. Based on the protective effects of HDL, we hypothesized that HDL-C levels could be associated with lung transplantation (LT) outcome. We thus looked for an association between basal HDL-C concentration and one-year mortality after LT. In this single-center prospective study including consecutive LTs from 2015 to 2020, 215 patients were included, essentially pulmonary fibrosis (47%) and chronic obstructive pulmonary disease (COPD) (38%) patients. Mortality rate at one-year was 23%. Basal HDL-C concentration stratified nonsurvivors to survivors at one-year (HDL-C = 1.26 [1.12-1.62] mmol/L vs. HDL-C = 1.55 [1.22-1.97] mmol/L, p = 0.006). Multivariate analysis confirmed that HDL-C concentration during the pretransplant assessment period was the only variable inversely associated with mortality. Moreover, mortality at one-year in patients with HDL-C concentrations ≤1.45 mmol/L was significantly higher (log-rank test, p = 0.00085). In conclusion, low basal HDL-C concentrations in candidates for LT are strongly associated with mortality after LT. To better understand this association, further studies in this field are essential and, in particular, a better characterization of HDL particles seems necessary.

Keywords: HDL-cholesterol; lipoprotein; lung transplantation; mortality; outcome.