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
Lopez et al. (Fri,) studied this question.