Real-World Economic Burden Associated with Progressive Pulmonary Fibrosis in the US: An Administrative Claims Database Analysis.

BACKGROUND AND

aimsAmong patients with non-idiopathic pulmonary fibrosis (non-IPF) interstitial lung disease (ILD), developing progressive pulmonary fibrosis (PPF) is associated with increased economic burden, inpatient (IP) admissions, and mortality. However, little is known about the burden within specific payer types. This retrospective study assessed the economic burden of PPF and associated time to first IP admission among distinct cohorts of Medicare Advantage Prescription Drug (MAPD) beneficiaries and commercial enrollees in the United States (US).

methodsMedical and pharmacy claims were analyzed among patients diagnosed with non-IPF ILD between 1/1/2017 and 11/30/2023. Patients who developed PPF (cases) were matched with those who had not yet progressed (comparators) using 1:1 propensity score matching (PSM) with replacement. The index date was the earliest PPF date for cases; the respective comparator was assigned an index date to create identical pre-index durations. Variable follow-up began on the index date and lasted for ≥ 3 months. Primary outcomes were all-cause and ILD-related healthcare resource utilization (HCRU) and costs (US dollars [USD] 2023) during follow-up. Outcomes were stratified by insurance type and weighted per patient per month (wPPPM). Multivariable models assessed all-cause costs and time to first IP admission, adjusting for covariates that remained imbalanced after PSM.

resultsA total of 60,171 matched pairs were analyzed: 50,683 MAPD and 9488 commercial. PSM generated well-balanced cohorts, except for race/ethnicity, ILD diagnosis year, unique pre-index medications filled (MAPD), and age group (commercial). For both insurance types, the PPF group was associated with significantly higher economic burden than the comparator group. All-cause costs averaged $3640 versus $1897 wPPPM (p < 0.001) in MAPD and $6164 versus $2741 (p < 0.001) in commercial. Differences were primarily driven by IP burden (MAPD: $1412 vs $507; commercial: $2094 vs $559; both p < 0.001). Mean length of IP stay was significantly longer among patients that developed PPF (MAPD: 0.9 vs 0.4 days; commercial: 0.5 vs 0.2 days; both p < 0.001). A generalized linear model showed that PPF was associated with higher adjusted all-cause costs (MAPD cost ratio [95% confidence interval {CI}]: 1.861 [1.807-1.916]; commercial: 2.096 [1.897-2.316]). Cox proportional hazards ratios (95% CI) showed a significantly higher hazard of first IP admission with PPF (MAPD: 2.060 [2.005-2.116]; commercial: 2.324 [2.133-2.532]). Notably, follow-up use of antifibrotics was low among patients with PPF (0.8% MAPD; 1.0% commercial).

conclusionFor MAPD and commercial cohorts, PPF was associated with significantly higher HCRU, costs, and hazard of IP admission. Differences in economic burden were primarily driven by IP utilization. These findings support the prioritization of treatments or strategies that attenuate the risk and rate of progression to mitigate downstream healthcare burden.