Impaired Lung Function in Liver Transplant Recipients Compared With the General Population: A Nationwide Matched Cohort Study

BACKGROUND: Liver transplant recipients have elevated risk of acute pulmonary infections, but the burden of chronic pulmonary diseases in liver transplant recipients remains largely unknown. We aimed to determine the association between living with a transplanted liver and both spirometry abnormalities and patient-reported dyspnea. METHODS: Adult liver transplant recipients from The Danish Comorbidity in Liver Transplant Recipients study and age- and sex-matched controls from The Copenhagen General Population Study were included. Spirometry was performed in 512 adult liver transplant recipients and 2010 matched controls. Outcomes included forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), airflow limitation, preserved ratio impaired spirometry (PRISm), and modified medical research (mMRC) dyspnea scale. RESULTS: Liver transplant recipients had higher prevalence of airflow limitation (10·7% versus 7·1%, P = 0.01) and PRISm (23·8% versus 11·8%, P < 0.001) than controls. When adjusted for age, sex, ethnicity, cumulative smoking, and educational status, living with a transplanted liver was associated with airflow limitation (adjusted odds ratio [aOR], 2.06; 95% confidence interval [CI], 1·41-3.01), PRISm (aOR, 2.88; 95% CI, 2.08-3.99), lower FEV1 (aOR, 363 mL; 95% CI, 297-430 mL), lower FVC (aOR, 549 mL; 95% CI, 467-632 mL), and worse dyspnea. Previous pulmonary infection was associated with airflow limitation in liver transplant recipients (aOR, 2.23; 95% CI, 1.06-4.66). CONCLUSIONS: Living with a transplanted liver was independently associated with airflow limitation and decreased FEV1 and FVC. Liver transplant recipients experienced more severe and frequent dyspnea. Increased awareness of pulmonary comorbidities in liver transplant recipients may be warranted.