The all-cause mortality rate of patients with idiopathic pulmonary fibrosis : nationwide population-based cohort study from the Korea National Health Insurance service database

Background: The mortality rate of patients with idiopathic pulmonary fibrosis (IPF) has been derived from results of several cohort studies comprising hundreds of patients. However, mortality data from the general population-based cohort are limited. Methods: We collected data for patients diagnosed with IPF (J841 or J8418) from 2006 to 2015 from the National Health Insurance (NHI) service database of Korea and followed these patients until December 2016. Among these patients, those having undergone a pulmonary function test within 6 months and chest computed tomography (CT) within 1 year of IPF diagnosis were defined as IPF patients in this study. Patients aged below 50 years, diagnosed with connective tissue diseases, or diagnosed with IPF before undergoing chest CT were excluded. The mortality rate of IPF patients was calculated as the rate per 1,000 person-year. Results: In total, 44,094 patients were newly diagnosed with IPF in the study period. The mean patient age was 69 years, and 66.8% of patients were male. Age-standardized mortality rates of IPF patients were 93.57 (95% confidence interval (CI): 91.75-95.38) and 68.58 (95% CI: 66.63-70.54) per 1,000 person-year in male and female patients, respectively. A new official guideline for diagnosis and management of IPF was released in 2011; there was no significant difference in the mortality rate in the time periods before and after 2011. Conclusions: We present the calculated mortality rate of IPF patients based on Korean population data. The mortality rate was higher in male IPF patients than in female IPF patients.