B41-30 Language Barriers and Diagnostic Accuracy in Interstitial Lung Disease: Are Non-English Speakers at Higher Risk for Misclassification?

Rationale Diagnostic delay and misclassification in interstitial lung disease (ILD) worsen outcomes and survival. In a Danish nationwide cohort of incident idiopathic pulmonary fibrosis (IPF), a diagnostic delay > 1 year independently predicted poorer progression-free survival (HR 1.70, 95% CI 1.18-2.46) and higher hospitalization rates (IRR 1.74, 95% CI 1.01-3.02).¹ Multidisciplinary discussion (MDD) has been shown to change the working diagnosis in roughly half of patients and improve diagnostic confidence.2–4 Outside ILD, language barriers—especially limited English proficiency (LEP)—are well-documented sources of diagnostic error and outcome disparities. Patients with limited English-language health literacy had over fourfold greater odds of lacking a qualified interpreter during diagnostic-error events (OR 4.4, 95% CI 1.3-14.9).5 LEP has also been associated with longer hospital stays, higher readmission risk, and increased mortality in respiratory illnesses.6–8 Whether LEP contributes specifically to ILD misclassification has not been systematically reviewed. Methods Following PRISMA 2020 guidance, PubMed and Embase were searched (Jan 2020 - Oct 2025) for: (1) studies on ILD/IPF diagnostic delay or reclassification; and (2) studies examining LEP, interpreter access, or language concordance and diagnostic accuracy or clinical outcomes in pulmonary or inpatient settings. Two reviewers independently screened and extracted quantitative results for narrative synthesis. Results Eight ILD-focused studies and ten LEP-focused studies met inclusion criteria. Diagnostic delay in ILD ranged from 7 months in sarcoidosis9 to > 1 year in IPF1; MDD revised initial ILD diagnoses in 40-53% of cases.2–4 Across large multicenter analyses, LEP was consistently linked to higher odds of adverse outcomes: 30-day readmission (OR 1.11, 95% CI 1.04-1.19) and ED revisits (OR 1.13, 95% CI 1.06-1.21) among hospitalized adults, with attenuation to null when professional interpreters were present.6 LEP was also associated with increased sepsis mortality (adjusted OR 1.35, 95% CI 1.18-1.55).7 No study directly evaluated LEP and ILD diagnostic error, but mechanistic overlap—history-taking, exposure assessment, and specialist referral—suggests plausible elevated risk. Conclusions ILD diagnostic pathways are inherently error-prone; independent literature confirms that language barriers impair diagnostic processes and worsen outcomes. Non-English-speaking patients with suspected ILD likely face higher misclassification risk through communication-mediated delays. Routine documentation of preferred language, mandatory professional interpreter use during MDDs, and multilingual diagnostic materials should be prioritized to mitigate disparities.