(C-050) Real-world Observational Study of Patients with Potential Non-Idiopathic Progressive Pulmonary Fibrosis and Risk Factors of Progression

Background: Progressive Pulmonary Fibrosis (PPF) is a subtype of interstitial lung disease (ILD) characterized by worsening lung function, dyspnea, physical performance, and quality of life. The known risk factors for disease progression include male sex, older age, lower forced vital capacity (FVC), and diffusing capacity of the lung for carbon monoxide (DLCO). There is limited information in the literature on the epidemiology and risk factors that may be early predictors of disease progression among PPF patients in the real-world setting.

Objectives: To identify potential PPF patients and describe their demographic and clinical characteristics as well as disease progression in the real-world setting.

Methods: This study was conducted using data extracted from the electronic medical records (EMR) of patients who were treated at Henry Ford Health. Adult patients with ≥1 inpatient or ≥2 outpatient medical claims with ICD-9/10-CM diagnosis codes indicative of non-idiopathic pulmonary fibrosis ILD from 01Jan2014 to 31Dec2021 were included and followed through 31Dec2022. Patients meeting one or more claims-based proxies for progression were included in the PPF cohort. Chart review was performed on 359 randomly selected patients to obtain FVC and DLCO values during the baseline year and follow up. Disease progression was defined as a decline of ≥10% in FVC or ≥15% in DLCO within 24 months; or acute exacerbation episode requiring ED visit or hospitalization during the follow up period. Descriptive statistics were used to summarize baseline demographics and clinical characteristics. A Cox proportional-hazard (PH) model adjusting for age, sex, and corticosteroid use was used to assess the influence of specific risk factors on the rate of disease progression. Time to worsening disease was assessed by using Kaplan Meier (KM) analysis.

Results: There were 6,413 ILD patients included in the cohort of whom 4,511 (70.3%) met ≥1 claims-based proxy for progression. Among the 359 PPF patients for whom chart review was completed, the mean age was 61.5 (SD: 14.9); 41.5% were male; and 37.0% were Black/African American. Male sex was a statistically significant risk factor (hazard ratio: 1.7, confidence intervals [1.2, 2.5]; P-value=0.003) for disease progression in the Cox model. Per the KM analysis, the median and mean time to disease progression was 6.7 and 5.3 (SE: 0.2) years, respectively.

Conclusions: Use of claims-based proxies for defining a PPF cohort is a novel methodologic approach in the absence of clinician review and is a viable method to better understand PPF patient progression and disease severity. Claims-based proxies may be used to identify patients at greatest risk or a need for treatment modification; thus, leading to improvement in outcomes and reduced burden of illness.