The prognostic role of high-density lipoprotein cholesterol/C-reactive protein ratio in idiopathic pulmonary fibrosis

Abstract

Background: The prognosis of idiopathic pulmonary fibrosis (IPF) patients is highly heterogeneous. Abnormalities in lipids and their metabolism play an important role in the development of IPF. Aim: To investigate the value of lipid parameters, C-reactive protein (CRP) and high-density lipoprotein cholesterol/C-reactive protein (HDL-C/CRP) ratio levels in the prognosis of IPF patients. Design: An observational cohort study. Methods: We collected baseline data of non-IPF controls and IPF patients, and IPF patients were followed up for 4 years. All-cause death or lung transplantation and IPF-related death were the outcome events. Receiver operating characteristic curves and Cox proportional hazards models were used to analyze the predictive effect of lipid parameters, CRP and HDL-C/CRP ratio on the prognosis of IPF patients. Results: IPF patients had lower HDL-C, HDL-C/CRP ratio and higher CRP compared to non-IPF controls. IPF patients who died or underwent lung transplantation were older and had worse pulmonary function, lower HDL-C, HDL-C/CRP ratio and higher CRP compared with surviving patients. HDL-C/CRP ratio was better than HDL-C and CRP in predicting all-cause death or lung transplantation. IPF patients with low HDL-C/CRP ratio had shorter survival times. The HDL-C/CRP ratio and diffusing capacity for carbon monoxide(DLCO)% of predicted were independent protective factors for all-cause death or lung transplantation and IPF-related death in IPF patients, while age and gender-age-physiology (GAP) Stage ≥ 2 (HR = 4.927) were independent risk factors for all-cause death or lung transplantation. Age > 65 years (HR = 3.533) was an independent risk factor for IPF-related death. Conclusion: HDL-C/CRP ratio was a valid predictor of clinical outcomes in IPF patients, including all-cause death or lung transplantation and IPF-related death.