Background: Idiopathic pulmonary fibrosis (IPF) is a lethal chronic interstitial lung disease (ILD) of unknown cause and having a variable and unpredictable course. This study aimed to summarize the clinical features and follow-up outcomes and to identify potential factors useful for the assessment of prognosis in IPF.
Methods: Two hundred and ten patients hospitalized and diagnosed as IPF in our unit from January 1999 to June 2007 were enrolled into this study. The baseline demographic, clinical, radiologic and physiologic characteristics were summarized. Clinical follow-up data until February 2010 were collected, and the median survival time and 1-, 2-, and 5-year survival rates, as well as the influences of the summarized baseline variables on the prognosis were analyzed.
Results: The age at diagnosis as IPF was (64 ± 10) years, the duration before diagnosis of 106 patients (50%) was shorter than 2 years, and 73% were males. One hundred and forty-five patients (69%) had a history of smoking with a median pack-year of 18. Eighty-nine patients (42%) had emphysema and 62 patients (29%) pulmonary arterial hypertension (PAH). One hundred and twenty-four patients were followed up, of which 99 patients died from various causes including respiratory failure related to IPF (93%). The follow-up period was (21 ± 23) months. The median survival time was 38 months. The 1-, 2-, and 5-year survival rates were 61%, 52%, and 39%, respectively. Multivariate analysis showed clubbing, PAH, duration from initial onset to diagnosis, and forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) were independent prognostic indicators of IPF.
Conclusion: IPF patients who have clubbing, PAH, a higher FEV1/FVC, and a short duration from initial onset to diagnosis have a poorer outcome.