Mapping the Geographic Distribution of Lung Transplant Centers and Smoking-Associated Diseases Across the United...

Chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) are progressive lung diseases strongly associated with cigarette smoking, together accounting for nearly 50% of lung transplants annually. Given this widespread disease burden, we aimed to assess whether the uneven distribution of transplant centers contributes to regional disparities in lung transplant access for patients with COPD and IPF.

We conducted a cross-sectional analysis using data from multiple, publicly available databases. We analyzed state-level data on cigarette users, COPD or IPF deaths, lung transplant centers, and recipients of lung transplants for COPD or IPF. To identify regions where transplant services may be inadequate relative to the burden of smoking-associated diseases, we also created 2 novel metrics: the cigarette users-to-transplant recipients (CUT) ratio and the smoking-associated disease deaths-to-transplant recipients (SADT) ratio.

Across states, there were significant negative correlations between transplant center density and both the CUT and SADT ratios. Moreover, states without a transplant center had significantly higher CUT and SADT ratios and fewer lung transplant recipients per capita than states with more than 3 centers per 100,000 square miles. Choropleth maps further illustrated that CUT and SADT ratios are higher in regions with a lower density of transplant centers.

These findings reveal geographic disparities in access to lung transplants for COPD or IPF, highlighting the need to provide additional support to candidates in states without lung transplant centers. Future studies should focus on identifying specific patient populations who encounter social or geographic barriers to transplant care.