Factors Associated with Listing for Lung Transplantation in Ipf Patients: As Analysis of the Pulmonary Fibrosis Foundation Registry

Abstract

Rationale and Objectives: Lung transplantation is a potentially life-saving treatment option for patients with idiopathic pulmonary fibrosis (IPF); however, not all eligible candidates get referred and listed for transplantation. Amongst IPF patients within the Pulmonary Fibrosis Foundation Patient Registry (PFF-R), we sought to determine the proportion of patients who undergo lung transplant listing and the characteristics associated with transplant listing.

Methods: An analysis of IPF patients with at least six months of follow-up data was performed. Patients with well-established contraindications to lung transplantation were excluded. Two complementary analyses were performed.  The 'prevalent' population included all patients with IPF at time of enrollment into the registry. The 'incident severe' population included all patients with IPF who progressed to GAP Stage 3.

Results: Of the 2,003 patients in the PFF-R, 475 patients were included in the 'prevalent' population.  Of this group, only 42 (8.8%) were either listed for or underwent lung transplant. Univariable analysis of the 'prevalent' population found age (per 10 year increase, OR 0.531, p=0.0025), percent predicted FVC (OR 0.572, p=<0.0001), percent predicted DLCO (OR 0.606, p<0.0001), 6-minute walk distance (per 50 m, OR 0.831, p =0.019), and oxygen use at rest (OR 5.157, p<0.0001) were predictive of listing.  On multivariable analysis, age (per 10 year increase, OR 0.558, p=0.0088), percent predicted FVC (OR 0. 728, p=0.0161), and oxygen use at rest (OR 3.264, p=0.0029) remained significant predictors for lung transplant listing. The 'incident severe' group consisted of 176 patients (8.8%).  24 patients (13.6%) from this cohort were either listed for or received a transplant. Only age (per 10 year increase, OR 0.0286, p=0.0465) was associated with transplant listing on univariable analysis in the Incident severe population. 

Conclusion:  Only a small proportion of potentially eligible patients with IPF are listed for lung transplantation, even when seen at pulmonary fibrosis centers of excellence. Advanced age appears to be the primary factor associated with failure to be listed.

Note:

Funding Declaration: This study was supported by the Pulmonary Fibrosis Foundation in the form of statistical support.

Conflict of Interest: The authors have no direct conflicts of interest to report with regard to this manuscript.

Ethical Information: Racial disparity in access to Ltx has been noted in other studies and the failure to demonstrate this might have resulted from the demographics of patients referred and seen at PFF Centers or those who consented for inclusion in the PFF-R.

Keywords: idiopathic pulmonary fibrosis, lung transplantation, Interstitial lung disease