Radiographic progression of interstitial lung disease portends long-term mortality risk

Among patients with systemic sclerosis-interstitial lung disease (SSc-ILD), radiographic progression of ILD over time is predictive of elevated long-term mortality, as shown in a study.

Researchers used data from the Scleroderma Lung Studies (SLS) I and II, trials that assessed the safety and efficacy of cyclophosphamide (SLS I and II) and mycophenolate (SLS II) for the treatment of SSc-ILD. They evaluated the changes in the extent of ILD over time on high-resolution computed tomography scans of the chest in relation to mortality outcomes. Progression was defined as an increase in quantitative ILD (QILD) score of ≥2 percent.

The analysis included 82 and 90 SLS I and II participants, respectively, who had follow-up imaging scans. Thirty-four (41 percent) participants in SLS I and 28 (31 percent) in SLS II experienced an increase in QILD of ≥2 percent for the whole lung at 12 and 24 months, respectively.

In SLS I, 66 (42 percent) patients overall had died within 12 years after randomization. On the other hand, 30 (21 percent) patients in SLS II died within 8 years after randomization. The most common cause of deaths in either cohort was underlying SSc.

Participants in both trials who showed radiographic progression had significantly worse long-term survival (p≤0.01). This was confirmed in the multivariable Cox models, with radiographic progression remaining significantly associated with worse long-term survival in SLS I (p=0.089) and II (p=0.014).

The present data suggest the potential of using radiographic endpoints as surrogates for mortality in SSc-ILD.