Statins' still controversial role in pulmonary fibrosis: What does the evidence show?

Pulmonary fibrosis (PF) represents the end stage of a broad range of interstitial lung diseases (ILDs). Statins are among the compounds which have been implicated in drug-induced ILD development. However, recent studies (both in vitro and in vivo) have provided evidence that statins may exert anti-inflammatory and anti-fibrotic effects potentially offering benefits to patients with PF. Several protective molecular mechanisms including the suppression of mevalonic acid pathway, the inhibition of NADPH oxidase activation in macrophages and the inhibition of several profibrotic mediators have been proposed to explain the observed in vivo decrease of the oxidative stress in the lung and the preservation of lung function in patients. Earlier clinical studies relating statins with drug-induced ILD development are contradicted by increasing new data showing the beneficial effects of statins in clinical outcomes in ILD patients who receive statins for concomitant cardiovascular indications. Future research may further elucidate the wide spectrum of pathways of IPF pathogenesis, and genetic heterogeneity, identifying clinically applicable biomarkers and specific endotypes thus recognizing in which patients statins could confer benefit and in which they might cause detrimental effects.