(704) Risk Factors for Persistent FEV(1)Decline Following COVID-19 Infection in Lung Transplant Recipients; a Single Australian Transplant Centre Experience

PURPOSE: There is a paucity of data regarding the impact of COVID-19 on allograft function in LTx recipients METHODS: We performed a retrospective cohort study of all living LTx recipients between Jan 2020 and Sep 2022. Patients with COVID-19 were identified by medical record review. Baseline characteristics at time of COVID-19 infection were recorded. Pre- and post-COVID-19 spirometry were used to identify persistent decline in graft function (≥10% of FEV(1) decline at 90 days after infection). Multivariable logistic regression was performed to identify risk factors associated with >10% decline in lung function which persisted at 90-days. RESULTS: 128/387 (33%) LTx recipients tested positive to SARS-CoV-2 during the study period;125 (97%) during the Omicron wave. In those with COVID-19, median (IQR) recipient age was 50.6 (22-77) with median time post-transplant 1522 (17 - 9842) days. The cohort was of Caucasian ethnicity 105 (82%), 48% were female and had high vaccination rates (98.4%). CLAD was present at time of infection in 48 (37.5%). Mortality rate was 10 (7.8%) with 40 (31%) requiring hospitalisation. 10 patients were excluded from further analyses (incomplete follow up data or duration post infection <90-days). Patients were followed for a median of 172 days (range 90-339) post infection. Mean FEV(1) across the whole cohort reduced by 10.2%. Persistent FEV(1) loss occurred in 37 (31.4%) patients. Multivariate analysis showed severe disease was independently associated with an increased risk of persistent FEV(1) decline (OR 5.55 [95%CI 2.28-13.48] p=<0.001). Non-Caucasian ethnicity (OR 2.83, [95%CI 0.92-8.65], p=0.07) and CLAD (OR 2.39, [95%CI 0.94-6.08], p=0.06), were weakly associated but positively correlated with persistent graft decline. There was no significant association between recipient age, gender, time post-transplant, early COVID therapy, SARS-CoV-2 variant or CKD with persistent FEV(1) decline. CONCLUSION: Persistent decline in allograft function at ≥90 days is common post SARS-CoV-2 infection in lung transplant recipients. Severe COVID-19 disease is strongly associated with this outcome and these patients should be monitored for risk of poor long-term graft recovery. Further investigation into the pathological mechanism responsible for persistent FEV(1) decline post SARS-CoV-2 infection is required.