Double Lung Transplantation Improves Survival in Interstitial Pulmonary Fibrosis

Individuals with pulmonary fibrosis experienced better long-term outcomes with double lung transplantation compared with single lung transplantation up until age 70, according to a study published in The Annals of Thoracic Surgery.

Findings were assessed using a retrospective analysis of all pulmonary fibrosis lung transplants in the United Network for Organ Sharing (UNOS) Database between 1987 and 2015 (9191 out of 29,779 total lung transplants). Post-transplant survival rates were determined using data from the Organ Procurement and Transplantation Network and Social Security.

The greatest survival benefit from double lung transplantation was seen in individuals with a mean pulmonary artery pressure (mPAP) <25 mm Hg. Although survival was similar between single and double lung transplants at 1 year of follow-up, the rates shifted considerably later on. The unadjusted 10-year survival rate for double lung transplant was 55%±1.5% compared with 32.0%±1.2% for single lung transplant.

As this was a retrospective study, investigators were unable to control for any unknown risk factors in participants that may have biased the results to favor double over single lung transplantation. However, investigators did attempt to control for this on propensity-matching analysis and multivariable regression. Other possible limitations were the fact that the coding for pulmonary fibrosis in the UNOS Database represents a heterogeneous group of diseases, and the data groups of individuals older than 70 years and with lung allocation scores ≥60 are small and may have therefore not reached statistical significance.

Study investigators concluded, “Double lung transplant demonstrates superior post-transplant survival compared to single lung transplant in patients with interstitial pulmonary fibrosis. We therefore recommend it as the procedure of choice for patients under the age of 70 years. [Double lung transplantation] can be performed at any degree of pulmonary hypertension and [lung allocation score] with similar long-term survival. However, [single lung transplantation] in the setting of an mPAP ≥30 or [a lung allocation score] ≥45 should be discouraged. Donor smoking history of more than 20 pack-years and low recipient PaCO₂ are independent predictors of reduced post-transplant survival in patients with [interstitial pulmonary fibrosis].”

Reference

Villavicencio MA, Axtell AL, Osho A, et al. Single versus double lung transplantation in pulmonary fibrosis: impact of age and pulmonary hypertension [published online May 24, 2018]. Ann Thorac Surg. doi:10.1016/j.athoracsur.2018.04.060