A case-control study of lung cancer in relation to silica exposure and silicosis in a rural area in Japan

Toshihide Tsuda, Yoshio Mino, Akira Babazono, Jun Shigemi, Tadahiro Otsu, Eiji Yamamoto, Susumu Kanazawa

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

PURPOSE: In southeast Okayama Prefecture, Japan, there have been reports of a high prevalence of silicosis among refractory brick production workers. Recently, a high mortality rate of lung cancer among the local residents has been observed. Therefore, a population based case-control study was conducted concerning the relationship between silica, silicosis, and lung cancer using multiple cancer controls. METHODS: Cases and controls were restricted to male subjects and information was obtained from death certificates from 1986 to 1993 in the area. Three categories of deceased control groups were selected: a series of deaths from liver cancer, colon cancer, and cancers of other organs, which was assumed not to be related to silica exposure. Age and smoking habits were adjusted by stratified analysis using the Mantel-Haenszel odds ratio estimates. Unconditional logistic regression analysis was also conducted to control potential confounding factors; such as age and smoking habits. RESULTS: The age-, smoking-adjusted odds ratios were 1.94 (0.94-4.43) for the colon cancer control group, 2.13 (1.19-3.85) for the other cancer control group related to silica exposure, and 2.94 (1.30-8.90) and 2.69 (1.43-5.37) related to silicosis, respectively. The direct weighted average using the estimates for colon and the other cancer controls was 2.06 (1.29-3.29) for silica exposure, and 2.77 (1.60-4.77) for silicosis. Histological or cytological types of lung cancer cases were obtained from 64.1% of the subjects (118/184). As for the histologic type of lung cancer, small cell carcinoma was higher among those who had been silica-exposed workers than the unexposed lung cancer cases and the data from the general Japanese population. On chest x-ray findings, elevated lung cancer mortality compared with cancers other than lung cancer was demonstrated among patients without large opacities. CONCLUSIONS: Silica exposure increased the lung cancer mortality in the area. A high lung cancer mortality rate in the area could be explained by silica exposure and silicosis prevalence in this area.

Original languageEnglish
Pages (from-to)288-294
Number of pages7
JournalAnnals of Epidemiology
Volume12
Issue number5
DOIs
Publication statusPublished - 2002

Fingerprint

Silicosis
Silicon Dioxide
Case-Control Studies
Lung Neoplasms
Japan
Colonic Neoplasms
Mortality
Smoking
Control Groups
Habits
Odds Ratio
Neoplasms
Death Certificates
Small Cell Lung Carcinoma
Liver Neoplasms
Population
Thorax
Logistic Models
Regression Analysis
X-Rays

Keywords

  • Cancer Mortality
  • Case-Control Study
  • Lung Neoplasm
  • Pneumoconiosis
  • Refractory Brick Workers

ASJC Scopus subject areas

  • Medicine(all)
  • Public Health, Environmental and Occupational Health
  • Epidemiology

Cite this

A case-control study of lung cancer in relation to silica exposure and silicosis in a rural area in Japan. / Tsuda, Toshihide; Mino, Yoshio; Babazono, Akira; Shigemi, Jun; Otsu, Tadahiro; Yamamoto, Eiji; Kanazawa, Susumu.

In: Annals of Epidemiology, Vol. 12, No. 5, 2002, p. 288-294.

Research output: Contribution to journalArticle

Tsuda, Toshihide ; Mino, Yoshio ; Babazono, Akira ; Shigemi, Jun ; Otsu, Tadahiro ; Yamamoto, Eiji ; Kanazawa, Susumu. / A case-control study of lung cancer in relation to silica exposure and silicosis in a rural area in Japan. In: Annals of Epidemiology. 2002 ; Vol. 12, No. 5. pp. 288-294.
@article{99e879f2232748a2a05ce99b09b2326b,
title = "A case-control study of lung cancer in relation to silica exposure and silicosis in a rural area in Japan",
abstract = "PURPOSE: In southeast Okayama Prefecture, Japan, there have been reports of a high prevalence of silicosis among refractory brick production workers. Recently, a high mortality rate of lung cancer among the local residents has been observed. Therefore, a population based case-control study was conducted concerning the relationship between silica, silicosis, and lung cancer using multiple cancer controls. METHODS: Cases and controls were restricted to male subjects and information was obtained from death certificates from 1986 to 1993 in the area. Three categories of deceased control groups were selected: a series of deaths from liver cancer, colon cancer, and cancers of other organs, which was assumed not to be related to silica exposure. Age and smoking habits were adjusted by stratified analysis using the Mantel-Haenszel odds ratio estimates. Unconditional logistic regression analysis was also conducted to control potential confounding factors; such as age and smoking habits. RESULTS: The age-, smoking-adjusted odds ratios were 1.94 (0.94-4.43) for the colon cancer control group, 2.13 (1.19-3.85) for the other cancer control group related to silica exposure, and 2.94 (1.30-8.90) and 2.69 (1.43-5.37) related to silicosis, respectively. The direct weighted average using the estimates for colon and the other cancer controls was 2.06 (1.29-3.29) for silica exposure, and 2.77 (1.60-4.77) for silicosis. Histological or cytological types of lung cancer cases were obtained from 64.1{\%} of the subjects (118/184). As for the histologic type of lung cancer, small cell carcinoma was higher among those who had been silica-exposed workers than the unexposed lung cancer cases and the data from the general Japanese population. On chest x-ray findings, elevated lung cancer mortality compared with cancers other than lung cancer was demonstrated among patients without large opacities. CONCLUSIONS: Silica exposure increased the lung cancer mortality in the area. A high lung cancer mortality rate in the area could be explained by silica exposure and silicosis prevalence in this area.",
keywords = "Cancer Mortality, Case-Control Study, Lung Neoplasm, Pneumoconiosis, Refractory Brick Workers",
author = "Toshihide Tsuda and Yoshio Mino and Akira Babazono and Jun Shigemi and Tadahiro Otsu and Eiji Yamamoto and Susumu Kanazawa",
year = "2002",
doi = "10.1016/S1047-2797(01)00271-X",
language = "English",
volume = "12",
pages = "288--294",
journal = "Annals of Epidemiology",
issn = "1047-2797",
publisher = "Elsevier Inc.",
number = "5",

}

TY - JOUR

T1 - A case-control study of lung cancer in relation to silica exposure and silicosis in a rural area in Japan

AU - Tsuda, Toshihide

AU - Mino, Yoshio

AU - Babazono, Akira

AU - Shigemi, Jun

AU - Otsu, Tadahiro

AU - Yamamoto, Eiji

AU - Kanazawa, Susumu

PY - 2002

Y1 - 2002

N2 - PURPOSE: In southeast Okayama Prefecture, Japan, there have been reports of a high prevalence of silicosis among refractory brick production workers. Recently, a high mortality rate of lung cancer among the local residents has been observed. Therefore, a population based case-control study was conducted concerning the relationship between silica, silicosis, and lung cancer using multiple cancer controls. METHODS: Cases and controls were restricted to male subjects and information was obtained from death certificates from 1986 to 1993 in the area. Three categories of deceased control groups were selected: a series of deaths from liver cancer, colon cancer, and cancers of other organs, which was assumed not to be related to silica exposure. Age and smoking habits were adjusted by stratified analysis using the Mantel-Haenszel odds ratio estimates. Unconditional logistic regression analysis was also conducted to control potential confounding factors; such as age and smoking habits. RESULTS: The age-, smoking-adjusted odds ratios were 1.94 (0.94-4.43) for the colon cancer control group, 2.13 (1.19-3.85) for the other cancer control group related to silica exposure, and 2.94 (1.30-8.90) and 2.69 (1.43-5.37) related to silicosis, respectively. The direct weighted average using the estimates for colon and the other cancer controls was 2.06 (1.29-3.29) for silica exposure, and 2.77 (1.60-4.77) for silicosis. Histological or cytological types of lung cancer cases were obtained from 64.1% of the subjects (118/184). As for the histologic type of lung cancer, small cell carcinoma was higher among those who had been silica-exposed workers than the unexposed lung cancer cases and the data from the general Japanese population. On chest x-ray findings, elevated lung cancer mortality compared with cancers other than lung cancer was demonstrated among patients without large opacities. CONCLUSIONS: Silica exposure increased the lung cancer mortality in the area. A high lung cancer mortality rate in the area could be explained by silica exposure and silicosis prevalence in this area.

AB - PURPOSE: In southeast Okayama Prefecture, Japan, there have been reports of a high prevalence of silicosis among refractory brick production workers. Recently, a high mortality rate of lung cancer among the local residents has been observed. Therefore, a population based case-control study was conducted concerning the relationship between silica, silicosis, and lung cancer using multiple cancer controls. METHODS: Cases and controls were restricted to male subjects and information was obtained from death certificates from 1986 to 1993 in the area. Three categories of deceased control groups were selected: a series of deaths from liver cancer, colon cancer, and cancers of other organs, which was assumed not to be related to silica exposure. Age and smoking habits were adjusted by stratified analysis using the Mantel-Haenszel odds ratio estimates. Unconditional logistic regression analysis was also conducted to control potential confounding factors; such as age and smoking habits. RESULTS: The age-, smoking-adjusted odds ratios were 1.94 (0.94-4.43) for the colon cancer control group, 2.13 (1.19-3.85) for the other cancer control group related to silica exposure, and 2.94 (1.30-8.90) and 2.69 (1.43-5.37) related to silicosis, respectively. The direct weighted average using the estimates for colon and the other cancer controls was 2.06 (1.29-3.29) for silica exposure, and 2.77 (1.60-4.77) for silicosis. Histological or cytological types of lung cancer cases were obtained from 64.1% of the subjects (118/184). As for the histologic type of lung cancer, small cell carcinoma was higher among those who had been silica-exposed workers than the unexposed lung cancer cases and the data from the general Japanese population. On chest x-ray findings, elevated lung cancer mortality compared with cancers other than lung cancer was demonstrated among patients without large opacities. CONCLUSIONS: Silica exposure increased the lung cancer mortality in the area. A high lung cancer mortality rate in the area could be explained by silica exposure and silicosis prevalence in this area.

KW - Cancer Mortality

KW - Case-Control Study

KW - Lung Neoplasm

KW - Pneumoconiosis

KW - Refractory Brick Workers

UR - http://www.scopus.com/inward/record.url?scp=0036283999&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0036283999&partnerID=8YFLogxK

U2 - 10.1016/S1047-2797(01)00271-X

DO - 10.1016/S1047-2797(01)00271-X

M3 - Article

C2 - 12062914

AN - SCOPUS:0036283999

VL - 12

SP - 288

EP - 294

JO - Annals of Epidemiology

JF - Annals of Epidemiology

SN - 1047-2797

IS - 5

ER -