Prevalence of drug-induced interstitial lung disease in Saudi Arabia: a real-world data study

Drug-induced interstitial lung disease (DI-ILD) is a serious but often under-recognized complication of various medications. Despite its potential reversibility if detected early, estimating its true prevalence is difficult due to clinical overlap with other interstitial lung disease (ILD) subtypes and the absence of specific biomarkers. We conducted a retrospective observational study using the Saudi Real-world Evidence Network between 2016 and 2023. ILD cases were identified using ICD-10 code J84.XX, and DI-ILD was defined either by diagnostic codes (J70.2-J70.4) or as a potential DI-ILD group based on recent exposure to drugs previously associated with pulmonary toxicity within six months prior to diagnosis. Demographics, comorbidities, and prescribing patterns were analyzed, and prevalence was calculated per 100,000 individuals. Among 2,858,141 individuals, 1,907 ILD cases were identified (66.7 per 100,000). Coded DI-ILD accounted for 1.26 per 100,000, while potential DI-ILD based on drug exposure was 28.6 per 100,000. Patients with potential DI-ILD were more often female (62.5%), older (mean age 61.1 ± 15.4 years), and had a higher comorbidity burden (mean Charlson Comorbidity Index 2.0 ± 2.1). Among ILD patients, 42.9% had recent exposure to at least one drug associated with pulmonary toxicity, most commonly antiarrhythmics (18.7%), including amiodarone (6.5%). These findings highlight the diagnostic complexity of DI-ILD in routine clinical practice and underscore the importance of systematic medication history review when evaluating patients with ILD. Exposure-based prevalence estimates should be interpreted cautiously and may serve as indicators of potential risk rather than confirmed diagnoses, supporting the need for enhanced diagnostic awareness and strengthened pharmacovigilance approaches.