Prevalence of idiopathic pulmonary fibrosis in Japan based on a claims database analysis

Yasuhiro Kondoh; Takafumi Suda; Yoshie Hongo; Manami Yoshida; Shinzo Hiroi; Kosuke Iwasaki; Tomomi Takeshima; Sakae Homma

doi:10.1186/s12931-022-01938-6

Prevalence of idiopathic pulmonary fibrosis in Japan based on a claims database analysis

Respir Res. 2022 Feb 8;23(1):24. doi: 10.1186/s12931-022-01938-6.

Authors

Yasuhiro Kondoh¹, Takafumi Suda², Yoshie Hongo³, Manami Yoshida⁴, Shinzo Hiroi⁴, Kosuke Iwasaki⁵, Tomomi Takeshima⁵, Sakae Homma⁶

Affiliations

¹ Department of Respiratory Medicine and Allergy, Tosei General Hospital, Aichi, Japan.
² The Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
³ Medical Affairs, Shionogi & Co., Ltd., 7F, Tekko Building, 1-8-2, Marunouchi, Chiyoda-ku, Tokyo, 100-0005, Japan. yoshie.hongo@shionogi.co.jp.
⁴ Medical Affairs, Shionogi & Co., Ltd., 7F, Tekko Building, 1-8-2, Marunouchi, Chiyoda-ku, Tokyo, 100-0005, Japan.
⁵ Milliman, Inc., Tokyo, Japan.
⁶ Department of Advanced and Integrated Interstitial Lung Diseases Research, School of Medicine, Toho University, Tokyo, Japan.

Abstract

Background: Idiopathic pulmonary fibrosis (IPF) is a cryptogenic chronic interstitial pneumonia with progressive fibrosis and a poor prognosis. A substantial number of epidemiological studies have been conducted in Europe and the United States (US). In contrast, in Japan, only one study reported the prevalence of IPF (10.0 per 100,000 population) using clinical data (2003-2007) from one prefecture; thus, the nationwide prevalence of IPF remains unknown. This study aimed to estimate the nationwide prevalence of IPF in Japan using a nationwide claims database.

Methods: We extracted data from a Japanese claims database provided by Medical Data Vision (MDV database, April 2008-March 2019) containing data from approximately 28 million patients from 385 acute-care hospitals. Patients with IPF (those diagnosed with IPF at least once) from April 2017 to March 2018 were identified in the MDV database. The number of patients in the MDV database was extrapolated nationwide using the fourth NDB Open Data (April 2017-March 2018), and the prevalence was estimated using demographic data as denominators. The prevalence in the US, considering the same definition of IPF, was also calculated and compared with that in Japan.

Result: The number of patients with IPF in the MDV database was 4278. The estimated nationwide number of patients in Japan was estimated to be 34,040 (mean age: 73 years, percentage of men: 73%), and the prevalence was 27 per 100,000 population. In comparison with that in the US, the prevalence was similar in men and relatively lower in women until the age of 75-79 years, and it was notably lower in both sexes aged ≥ 80 years.

Conclusions: We report the nationwide IPF prevalence in Japan using data from claims databases for the first time. The prevalence estimated in this study was higher than that reported in a previous study. The difference might be due to differences in study settings and definitions of IPF. Further research should be performed to determine the prevalence more accurately and compare it with those in other countries.

Keywords: Claims data; Epidemiology; Idiopathic pulmonary fibrosis; Japan; Prevalence.

Publication types

Multicenter Study

MeSH terms

Age Distribution
Aged
Aged, 80 and over
Databases, Factual
Female
Hospitalization / statistics & numerical data*
Humans
Idiopathic Pulmonary Fibrosis / epidemiology*
Insurance Claim Review / statistics & numerical data*
Japan / epidemiology
Male
Middle Aged
Prevalence
Retrospective Studies
Sex Distribution