Nearly half of systemic sclerosis patients with late-onset interstitial lung disease experience disease progression within four years, according to a recent study. 

The cohort study evaluated interstitial lung disease (ILD) incidence and progression in patients with late-stage systemic sclerosis (SSc). Among 969 participants enrolled in the Canadian Scleroderma Research Group cohort without prevalent ILD, 199 (21%) developed ILD over a median follow-up of 2.4 years. For late-onset SSc—defined as SSc of ≥7 years duration—the ILD incidence rate was 3.7 per 100 person-years, lower than the 5.4 per 100 person-years observed in early-onset SSc (relative risk, 0.68; 95% confidence interval [CI], 0.51-0.92).

Key risk factors for late-onset ILD included male sex, diffuse cutaneous involvement, myositis, elevated C-reactive protein, and presence of anti-topoisomerase I and anti-RNA polymerase III antibodies. In contrast, White patients were less likely to develop ILD. The study, published in Arthritis & Rheumatology, observed comparable lung function metrics in late- and early-onset ILD at diagnosis, with predicted forced vital capacity at 88% and 87%, respectively, and diffusion capacity for carbon monoxide at 64% and 62%.

ILD progression was documented in 45% of cases over four years, with no significant difference between late- and early-onset groups (hazard ratio, 1.11; 95% CI, 0.58-2.10). These findings suggest that ILD surveillance in patients with longstanding SSc is recommended, especially in those with identified risk factors. The optimal frequency and methods for monitoring have yet to be established and warrant further research.

Full disclosures can be found in the published study. This article has been accepted for publication and peer-reviewed but has not yet undergone copyediting, typesetting, pagination, or proofreading, which may result in differences from the final published version.