A39-30 Use of Antifibrotic Therapy Improves Case Selection of Patients With True Idiopathic Pulmonary Fibrosis in the Trinetx Database

Abstract Introduction Antifibrotic therapy with nintedanib or pirfenidone is the mainstay treatment for idiopathic pulmonary fibrosis (IPF). Pre-treatment baseline characteristics in real-world practice may suggest selection biases related to disease severity or diagnostic certainty. We describe the baseline characteristics of patients with IPF treated or not treated with antifibrotics in a real-world setting. Methods This was a retrospective cohort analysis using the TriNetX Collaborative Network (72 USA healthcare organizations). Adults older than 18 years with IPF (ICD-10 J84.112) diagnosed after 2014 were included. We excluded patients with alternative causes of interstitial lung disease (ILD). This included Cohort 1 (antifibrotic use within 1 year; N = 412) and Cohort 2 (antifibrotic use within 3 years; N = 673); Cohort 3 (no antifibrotic within 5 years; 18,000) was used as control. For statistical comparison, Cohort 1 was independently compared to Cohort 3, and Cohort 2 was independently compared to Cohort 3. This resulted in two sets of pairwise comparisons. T-tests were used for continuous variables and Chi-Square tests for categorical variables for these independent pairwise comparisons. A Bonferroni correction was applied setting the significance threshold at p 0.0025 (0.05 divided by 20 comparisons). Results Antifibrotic and non-antifibrotic cohorts had similar age at index (mean ∼73 years; p = 0.89), whereas antifibrotic cohorts were more likely to be male compared with the non-antifibrotic cohort (71% and 71% vs. 61%; p 0.001). Compared to the non-antifibrotic group, patients receiving antifibrotics demonstrated markedly higher frequencies of pulmonary fibrosis-related diagnoses before IPF coding, including pulmonary fibrosis-unspecified (59.7% and 62.9% vs. 39%; p 0.001), interstitial pulmonary disease-unspecified (76% and 77% vs. 33%; p 0.001), and other specified ILDs (21% and 21% vs. 13%; p 0.001). They also exhibited more dyspnea (67 and 70% vs. 45%; p 0.001), chronic cough (15% and 15% vs. 6%; p 0.001), and pulmonary physiology assessments, including spirometry testing (59% and 64% vs. 17%; p 0.001), and diffusing capacity testing (57% and 61% vs. 19%; p 0.001). Likewise, disease severity measured as chronic respiratory failure was more prevalent among antifibrotic cohorts (18 and 20% vs. 8%; p 0.001). Conclusion Compared to IPF patients not on antifibrotics, IPF patients on antifibrotics were more symptomatic, had better diagnostic work-up, and had more fibrotic ILD coding within 3 years. These findings call for careful interpretation of large research databases; antifibrotic use is concentrated among those with advanced or well-characterized IPF, whereas IPF patients not on antifibrotics had milder pulmonary disease or were more likely to be miscoded. This abstract is funded by: None