The efficacy of treatment for systemic sclerosis interstitial lung disease: results from a meta-analysis

Abstract

Background: This meta-analysis examined all randomized controlled trials (RCTs) comparing pharmacotherapy for systemic sclerosis (SSc)-interstitial lung disease (ILD) with placebo or alternative drugs on pulmonary function tests (PFTs), quality of life, dyspnea, skin thickness, and adverse events.

Material/methods: Forty studies were identified, and from these 2 RCTs examining cyclophosphamide and 1 examining bosentan met inclusion criteria (studies had to be randomized, have at least 20 SSc-ILD patients, and have PFTs as primary outcomes).

Results: Differences between groups for change of PFT scores between baseline and 12 months were not significant when the 3 trials were combined. The treatment effect of cyclophosphamide versus placebo on forced vital capacity revealed a mean difference of 3.30% (95% confidence interval, 0.06-6.54). Diffusing capacity and total lung capacity did not change.

Conclusions: This conservative yet significant effect of cyclophosphamide demonstrates the need for further investigation of its effectiveness on patient-important outcomes such as dyspnea and quality of life, which could not be evaluated by this meta-analysis. It may be that studies in SSc-ILD need outcomes that are more sensitive to change.