Interstitial lung disease progression after genomic usual interstitial pneumonia testing

Area of Science:

• Pulmonology
• Genomics
• Diagnostic Medicine

Background:

• A genomic classifier for usual interstitial pneumonia (gUIP) aids in diagnosing idiopathic pulmonary fibrosis (IPF).
• The clinical significance of a positive gUIP classification regarding disease progression is not well understood.

Purpose of the Study:

• To determine if a positive gUIP classification is associated with an IPF-like phenotype.
• To assess the relationship between gUIP classification and disease progression, defined by survival and lung function decline.

Main Methods:

• Retrospective analysis of 192 patients who underwent bronchoscopy and gUIP testing.
• Cox proportional hazards regression was used to assess the association between gUIP classification and 18-month progression-free survival (PFS).
• Joint regression models compared longitudinal changes in forced vital capacity (FVC) between gUIP classification groups.

Main Results:

• Positive gUIP classification was not statistically associated with reduced PFS (HR 1.58, p=0.14).
• Mean annual FVC decline was -101.8 mL in the positive gUIP group and -73.2 mL in the negative gUIP group (difference 28.7 mL, p=0.30).
• No significant difference in PFS or FVC decline was observed between groups.

Conclusions:

• Genomic classifier for usual interstitial pneumonia (gUIP) classification did not correlate with differential rates of progression-free survival.
• gUIP classification was not associated with significant differences in longitudinal forced vital capacity decline.
• The study suggests gUIP classification may not predict clinical IPF trajectory in patients undergoing diagnostic evaluation.