Effect of diagnosis on survival benefit of lung transplantation for end-stage lung disease

Abstract

Although certain forms of end-stage lung disease are debilitating, whether the associated mortality rate exceeds that of transplantation is unclear. We undertook analysis to clarify the survival benefit of lung transplantation for various types of end-stage lung disease. We analysed data for all patients listed for transplantation in the USA for emphysema, cystic fibrosis, or interstitial pulmonary fibrosis in the years 1992-94. The numbers of patients entered on the waiting list, post-transplantation, died waiting, and currently waiting were: emphysema group 1274, 843, 143, and 165; cystic fibrosis group 664, 318, 193, and 59; interstitial pulmonary fibrosis group 481, 230, 160, and 48. A time-dependent non-proportional hazard analysis was used to assess the risk of mortality after transplantation relative to that for patients on the waiting list. The clearest survival benefit from lung transplantation occurred in the cystic fibrosis group. The relative risks of transplantation compared with waiting were 0.87, 0.61, and 0.61 at 1 month, 6 months, and 1 year (p = 0.008), respectively. For interstitial pulmonary fibrosis, the corresponding relative risks were 2.09, 0.71, and 0.67 (p = 0.09). No survival benefit was apparent in the emphysema group. The risks of transplantation relative to waiting were 2.76, 1.12, and 1.10 at 1 month, 6 months, and 1 year, respectively, and the relative risk did not decrease to below 1.0 during 2 years of follow-up. These findings suggest that lung transplantation does not confer a survival benefit in patients with end-stage emphysema by 2 years of follow-up. Other benefits not accounted for in this analysis such as improved quality of life, however, may justify lung transplantation for these patients.