Acute exacerbations of idiopathic pulmonary fibrosis: Does clinical stratification or steroid treatment matter?

Abstract

Acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) is defined as a sudden acceleration of the disease with the appearance of pulmonary infiltrates superimposed on the characteristic pattern of IPF that leads to a significant decline in lung function. It has high in-hospital mortality rates, despite medical treatment with systematic steroids. We sought to investigate whether there were in-hospital mortality differences according to clinical stratification (AE, suspected AE, or AE of known cause) and/or treatment with systemic steroids. We reviewed the clinical characteristics and outcomes of patients with IPF admitted to our hospital during the years 2003-2014 due to a worsening of their clinical status. We identified 50 IPF patients, 9 with AE (18%), 12 with suspected exacerbation (24%), and 29 with AE of known cause (58%), mostly respiratory infections. In-hospital mortality was similar in the three groups (33% vs. 17% vs. 34%, respectively). Likewise, we did not find differences between them with respect to the use of systemic steroids (length of treatment duration or total dose). Nevertheless, there was an independent association between in-hospital mortality and high average daily steroid dose. We did not observe significant differences in prognosis or use of systemic steroids according to current diagnostic stratification groups in patients hospitalized because of an exacerbation of IPF.

Keywords: Idiopathic pulmonary fibrosis; acute exacerbation; corticosteroid therapy; usual interstitial pneumonia.

Figure 1.

Schematic representation of the studied population. The main reasons for excluding patients were planned hospital admission without worsening of the respiratory symptoms (n = 21), patients with severe immunosuppression resulting from bone marrow transplantation or solid organ transplant (n = 2), severe hematological diseases (n = 6), and active malign neoplasm (n = 5). ICD: International Classification of Diseases.

Figure 2.

Survival analysis for the three definition groups. (a) Survival analysis comparing AE, SAE and AEKE (b) Survival analysis comparing idiopathic excerbation (combined AE/SAE patients) and AEKE. AE: acute exacerbation; SAE: suspected acute exacerbation; AEKE: acute exacerbation of known etiology.

Figure 3.

(a) ROC curves of daily corticosteroids dose in relation to in-hospital mortality and (b) survival analysis between patients with high and low doses of corticosteroids. ROC: receiver operating characteristics.