Effect of cyclosporine A on mortality after acute exacerbation of idiopathic pulmonary fibrosis

Background: There is currently no recognized treatment for acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF), and the effect of cyclosporine A in patients with AE-IPF remains unknown. Methods: We identified patients with AE-IPF who received high-dose methylprednisolone plus cyclosporine A or high-dose methylprednisolone alone from July 1, 2010, to March 31, 2014, using the Diagnosis Procedure Combination database in Japan. We compared in-hospital mortality between patients with and without cyclosporine A by multivariable logistic regression analysis, with adjustment for patient and hospital covariates. Unmeasured confounders were accounted for by instrumental variable analysis based on differential distance. Results: Eligible patients (n=7,989) were divided into a high-dose methylprednisolone plus cyclosporine A group (n=384) and a high-dose methylprednisolone alone group (n=7,605). There was no significant difference in terms of in-hospital mortality between the groups according to multivariable logistic regression [odds ratio, 1.27; 95% confidence interval (CI), 0.99-1.64; P=0.06] or instrumental variable analysis (odds ratio, 0.94; 95% CI, 0.12-7.67; P=0.96). Conclusions: Cyclosporine A did not reduce in-hospital mortality in patients with AE-IPF. Randomised controlled studies are required to confirm this apparent lack of effect of cyclosporine A in AE-IPF.