title: Occupational and environmental factors and idiopathic pulmonary fibrosis in Japan.
abstract: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing interstitial lung disease of unknown etiology. Environmental factors, especially occupational agents, may be of great importance in the manifestation of IPF. We examined the relationship between occupational and environmental factors and IPF in Japan. A multicenter hospital-based case-control study was performed in 2001. Included were 102 cases aged 40 years or over who were within 2 years of having been diagnosed in accordance with the most recent criteria. Controls, aged 40 years or over, were 55 hospitalized patients diagnosed as having acute bacterial pneumonia and four outpatients with common colds. Data on occupational and environmental factors were obtained from a questionnaire. Multiple logistic regression analysis was used to estimate the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of IPF for single factors with adjustment for age, sex and region. Compared with controls, cases were more likely to have been managers, officials or production workers and less likely to have been protective service or materials handling workers. Clerical and related work was significantly related to a decreased risk of IPF after further adjustment for pack-years of smoking (OR = 0.42; 95% CI = 0.18-0.95). Exposure to metal dust was significantly associated with an increased risk of IPF (OR = 9.55; 95% CI = 1.68-181.12). From 20.0 to 39.9 pack-years of smoking was significantly associated with an increased risk of IPF (OR = 3.23; 95% CI = 1.01-10.84). Our results appear to confirm data from previous epidemiologic studies. Metal dust exposure may be a particularly important risk factor for IPF.
authors.affiliation: Department of Public Health, Fukuoka University School of Medicine, Fukuoka, Japan. miyake_y@cis.fukuoka-u.ac.jp
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Miyake
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sasaki
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Kingo
authors.initials: K
authors.lastname: Chida
authors.forename: Arata
authors.initials: A
authors.lastname: Azuma
authors.forename: Takafumi
authors.initials: T
authors.lastname: Suda
authors.forename: Shoji
authors.initials: S
authors.lastname: Kudoh
authors.forename: Naomasa
authors.initials: N
authors.lastname: Sakamoto
authors.forename: Kazushi
authors.initials: K
authors.lastname: Okamoto
authors.forename: Gen
authors.initials: G
authors.lastname: Kobashi
authors.forename: Masakazu
authors.initials: M
authors.lastname: Washio
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Inaba
authors.forename: Heizo
authors.initials: H
authors.lastname: Tanaka
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D004391:Dust; D005260:Female; D006801:Humans; D008297:Male; D008670:Metals / Q000009:adverse effects; D008875:Middle Aged; D009784:Occupational Diseases / Q000209:etiology*; D016017:Odds Ratio; D011658:Pulmonary Fibrosis / Q000209:etiology*; D012044:Regression Analysis; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects
chemical_list: D004391:Dust; D008670:Metals