Patients with systemic autoimmune rheumatic disease (SARD) are at high risk of developing interstitial lung disease (ILD). We sought to gain insight into the pharmacological and non-pharmacological treatments being used by patients with SARD-associated ILD (SARD-ILD) following ILD progression.

This was a retrospective, observational cohort study.

Optum Clinformatics Data Mart administrative medical and pharmacy claims database in the USA.

Patients with SARD-ILD who had an incident ILD diagnosis and progression between January 2018 and March 2023.

Treatment patterns and healthcare services utiliation were descriptively summarised for baseline and follow-up periods.

We identified 6431 patients with SARD-ILD and evidence of ILD progression (mean age, 71.2 years; 75.3% female; 68.9% white). The mean (SD) time between the initial SARD-ILD diagnosis and the onset of ILD progression (index date) was 104 (201) days. On average, patients were followed for 936 (467) days.

Oral corticosteroids were the most common treatment post-progression (69.5%), followed by non-biologic disease-modifying antirheumatic drugs (non-biologic DMARDs) (41.6%), biologic DMARDs (15.5%) and immunomodulators (15.4%). Antifibrotics were received by 3.5% of patients. Supplemental oxygen was the most frequent non-pharmacological treatment (48.9%). For the baseline period, 53.0% and 42.1% of patients used inpatient and emergency department services, respectively. During the follow-up, 69.7% and 62.8%, respectively, used these services.

The high use of corticosteroids and limited use of DMARDs and antifibrotics post-progression in this descriptive study implies a significant gap between current practice and optimal management of patients with SARD-ILD.