Survival determinants in lung transplant patients with chronic allograft dysfunction

Abstract

Background: Chronic lung allograft dysfunction (CLAD) remains the leading cause of mortality after lung transplantation.

Methods: In this retrospective single-center study, we aimed to identify different phenotypes of and risk factors for mortality after CLAD diagnosis using univariate and multivariate Cox proportional hazard survival regression analysis.

Results: CLAD was diagnosed in 71 of 294 patients (24.2%) at 30.9±22.8 months after transplantation. Pulmonary function was obstructive in 51 (71.8%) of the CLAD patients, restrictive in 20 (28.2%) patients, of whom 17 had persistent parenchymal infiltrates on pulmonary computer tomography (CAT) scan. In univariate analysis, previous development of neutrophilic reversible allograft dysfunction (NRAD, P=0.012) and a restrictive pulmonary function (P=0.0024) were associated with a worse survival, whereas there was a strong trend for early development of CLAD and persistent parenchymal infiltrates on CAT scan (P=0.067 and 0.056, respectively). In multivariate analysis, early development of CLAD (P=0.0067), previous development of NRAD (P=0.0016), and a restrictive pulmonary function pattern (P=0.0005) or persistent parenchymal infiltrates on CAT scan (P=0.0043) remained significant.

Conclusion: Although most CLAD patients develop an obstructive pulmonary function, 28% develop a restrictive pulmonary function, compatible with the recently defined restrictive allograft syndrome phenotype. Early-onset CLAD, previous development of NRAD, and the development of restrictive allograft syndrome are associated with worse survival after CLAD has been diagnosed.