Burden of Idiopathic Pulmonary Fibrosis Progression: A 5-Year Longitudinal Follow-Up Study.

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease with an unpredictable course. An observational study was set up using the French hospital discharge database to describe the reasons, outcomes and costs of hospitalisations related to this disease. Patients newly hospitalised for idiopathic pulmonary fibrosis (ICD-10 code: J84.1) in 2008 were identified and followed for 5 years. As J84.1 includes other fibrotic pulmonary diseases, an algorithm excluding age<50 years and presence of a differential diagnosis in the following year was defined. Overall, 6,476 patients were identified; of whom 30% were admitted through the emergency unit and 12% died during their first hospitalisation. Most of patients were hospitalised at least once for one or several acute events (n = 5,635; 87.0% of patients), of whom 36.5% of patients with an acute respiratory worsening (in-hospital mortality of 17.0% and median cost of €3,224; interquartile range (IQR €889-6,092)), 43.7% of patients with a respiratory infection (in-hospital mortality of 29.5% and median cost of €5,432 (IQR, €3,620-9,115)) and 51.7% of patients with a cardiac event (in-hospital mortality of 35.7% and median cost of €4,584 (IQR, €2,803-6,399)); 30.2% of these events occurred during the first hospitalisation. Finally, the 3-year in-hospital mortality crude rate was 36.8%. This study is the first providing extensive data on hospitalisations in patients with pulmonary fibrosis, mostly idiopathic, in France, demonstrating high burden and hospital cost.