The efficacy of anti-fibrotic agents for acute exacerbation of idiopathic pulmonary fibrosis

Abstract

Background: Acute exacerbation (AE) is a severe complication of idiopathic pulmonary fibrosis (IPF). The clinical benefit of anti-fibrotic agents for AE-IPF is unclear. We retrospectively reviewed the prognosis of AE-IPF according to treatment regimen. Methods: A total of 67 patients with AE-IPF between May 2005 and July 2016 were reviewed. IPF was diagnosed according to the ATS/ERS/JRS/ALAT clinical practice guideline. AE-IPF was diagnosed according to the revised definition and diagnostic criteria proposed by international working group. The clinical characteristics and survival were then compared. Results: Fifty-seven patients (85.1%) were male and the median age was 77 years. The median serum KL-6 levels were 1331 U/mL and the median P/F ratio was 248 at the diagnosis of AE-IPF. All patients were treated with corticosteroids, including intravenous high-dose corticosteroid therapy (n=65). Twenty-nine patients (43.3%) were treated with immunosuppressant agents (cyclosporine A, n=23; cyclophosphamide, n=7) and 16 patients (23.9%) were treated with anti-fibrotic agents (pirfenidone, n=13; nintedanib, n=4). The median overall survival time (OS) was 4.6 months. The median OS in patients with anti-fibrotic agents was 6.6 months as compared to 3.9 months in those without anti-fibrotic agents (p=0.16). The median OS in patients with immunosuppressant agents was not significantly different from that in patients without immunosuppressant agents (4.9 months vs. 1.7 months, p=0.702). Conclusion: AE-IPF treated with anti-fibrotic agents showed good prognosis. Further investigation is necessary to elucidate the efficacy of anti-fibrotic agents in patients with AE-IPF.