Lung transplantation outcomes in patients from socioeconomically distressed communities

BACKGROUND

Previous studies have demonstrated racial and gender disparities in lung allocation, but contemporary data regarding socioeconomic disparities in post-transplant outcomes are lacking. We evaluated the impact of a composite socioeconomic disadvantage index on post-transplant outcomes.

METHODS

The Scientific Registry of Transplant Recipients identified 27,763 adult patients undergoing isolated primary lung transplantation between 2005 and 2020. Zip code-level socioeconomic distress was characterized using the Distressed Communities Index (DCI: 0-no distress, 100-severe distress) based on education level, poverty, unemployment, housing vacancies, median income, and business growth, and patients were stratified into high (DCI ≥60) or low (DCI <60) distressed groups.

RESULTS

Recipients from high-distress communities (n = 8006, 28.8%) were younger (59years [interquartile range {IQR} 50-64] vs 61years [IQR 52-66]), less often white (73 vs 85%), less likely to have a college degree (45 vs 59%), and more likely to have public insurance (57 vs 49%, all p < 0.001) compared to those from low-distress communities. Additionally, high-distress recipients were more likely to have group A diagnoses (32 vs 27%) and undergo bilateral lung transplants (72.4 vs 69.3%, all p < 0.001). Post-transplant survival at 5years was 55.7% (95% confidence interval [CI]: 54.4-56.9) in high-distress recipients and 58.2% (95% CI: 57.4-58.9) in low-distress recipients (p = 0.003). After adjustment, high distress level was independently associated with an increased risk of 5-year mortality (hazard ratio:1.09, 95% CI:1.04-1.15).

CONCLUSIONS

Recipients from distressed communities are at increased mortality risk following lung transplantation. Efforts should be focused on increased resource allocation and further study to better understand factors which may mitigate this disparity.

Fibroproliferation in chronic lung allograft dysfunction: Association of mesenchymal cells in bronchoalveolar lavage with phenotypes and survival

BACKGROUND

Chronic lung allograft dysfunction (CLAD), the primary cause of poor outcome after lung transplantation, arises from fibrotic remodeling of the allograft and presents as diverse clinical phenotypes with variable courses. Here, we investigate whether bronchoalveolar lavage (BAL) mesenchymal cell activity at CLAD onset can inform regarding disease phenotype, progression, and survival.

METHODS

Mesenchymal cell colony-forming units (CFUs) were measured in BAL obtained at CLAD onset (n = 77) and CLAD-free time post-transplant matched controls (n = 77). CFU counts were compared using Wilcoxon's rank-sum test. Cox proportional hazards and restricted means models were utilized to investigate post-CLAD survival.

RESULTS

Higher mesenchymal CFU counts were noted in BAL at the time of CLAD onset than in CLAD-free controls. Patients with restrictive allograft syndrome had higher BAL mesenchymal CFU count at CLAD onset than patients with bronchiolitis obliterans syndrome (p = 0.011). Patients with high mesenchymal CFU counts (≥10) at CLAD onset had worse outcomes than those with low (<10) CFU counts, with shorter average survival (2.64 years vs 4.25 years; p = 0.027) and shorter progression-free survival, defined as time to developing either CLAD Stage 3 or death (0.97 years vs 2.70 years; p < 0.001). High CFU count remained predictive of decreased overall survival and progression-free survival after accounting for the CLAD phenotype and other clinical factors in multivariable analysis.

CONCLUSIONS

Fulminant fibroproliferation with higher mesenchymal CFU counts in BAL is noted in restrictive allograft syndrome and is independently associated with poor survival after CLAD onset.