OBJECTIVES: Bronchiolitis Obliterans Syndrome (BOS), a rapidly progressive obstructive airway disease, affects up to half of all lung transplant patients within 5 years of transplantation and leads to respiratory failure and death. Clinical guidelines recommend post-transplant lung function testing, with intensity decreasing over time. This study used real-world data to assess lung function testing in lung transplant (LTx) recipients in the U.S.

METHODS: Data sources for this longitudinal retrospective study were the Medicare Limited Dataset and the IQVIA PharMetrics Plus commercial database, both with enrollment, demographic and medical claim data. The study period was 1/1/06 to 9/30/18. Study patients had 1+ inpatient claims with a procedure or diagnosis code for lung transplant, following a 6-month period with no evidence of transplantation. Commercially insured patients were limited to age <65y because those ≥65y typically have primary coverage through Medicare. Outcome measures were lung function testing rates 1-5 years post-LTx.

RESULTS: Among 1,776 Medicare and 367 commercially insured patients, all received lung function testing in the first year after LTx; nearly 9 in 10 underwent spirometry, with an average of 8.4±:5.9 and 10.6±:7.6 tests per patient for Medicare and commercially insured patients, respectively. Nearly all patents had at least one lung function test in years 2-5 but patients received fewer tests, on average. Spirometry testing declined in year 2 to 3.0±:3.2 (Medicare) and 3.2±:4.5 (commercial) per-patient, and by year 5 were 0.5±:1.6 (Medicare) and 0.4±:1.7 (commercial). Mean per-patient bronchoscopy rates were lower for Medicare in the first post-transplant year (5.7±3.3 vs. 8.6±6.4) but identical by year 5 (0.1±0.5; 0.1±0.7). Rates of plethysmography, lung diffusion capacity, lung function volume, and pulse oximetry also declined in both cohorts.

CONCLUSIONS: Real-world claims data suggests that providers are adherent to post-transplant lung function monitoring guidelines, with consistent patterns of monitoring observed in public and private payers.