Liu Bo-qi, Jiang Jing-mei, Chen Zheng-ming, Chen Jun-shi, Zhang Kong-lai, Zeng Xian-jia, Zhao Ping, Boreham Jillian, Wu Yan-ping, Li Jun-yao, Peto Richard
Department of Epidemiology, National Cancer Institute, Chinese Academy of Medical Sciences, Beijing 100021, China.
Zhonghua Yi Xue Za Zhi. 2006 Feb 14;86(6):380-5.
To examine the relationship between smoking and risk of esophageal cancer (EC), and present a theoretical framework of control selection in population-based case-control study which was incorporated into a nationwide retrospective survey of mortality in China.
A large-scale population-based case-control study was incorporated into the nationwide retrospective survey of mortality conducted 1989 - 1991 in 24 urban cities selected by non-random sampling and 79 rural counties selected from 3000 counties included in the 1973 - 1975 cancer distribution survey by random sampling during. A questionnaire survey was conducted by home visit to investigate the death causes and smoking history of 19 734 deceased male adults who died of esophageal cancer during 1986 - 1988 at the age >or= 35. Two control groups were set up to undergo questionnaire survey by home visit to investigate the smoking history of the deceased persons and the informants. Control group I included the surviving spouses or other informants of 31 989 male adults who died of non-malignant digestive diseases during 1986 - 1988 at the age >or= 35, and control group II included 104 846 male spouses of the deceased female adults who died of different causes during 1986 - 1989 at the age >or= 35. The relative risks and population smoking attributable risks for EC were calculated using non-conditional logistic model, and the results were compared for consistency between the analyses using two different control groups.
The EC absolute death rates were higher in the smokers than in the non-smokers in all urban and rural area groups. The total EC absolute death rate per 1000 among the non-smokers vs. smokers was 0.37:0.65 in the urban areas, 0.99:1.29 in the inland rural areas, and 1.09:1.62 in the coastal rural areas in the control group I, and there was a similar trend in the control group II. There was a significant dose-response relation between the period of smoking and the death risk of EC and between the daily cigarette consumption and the death risk of EC. The risk ratios, for example, for cigarette per day < 10, 10-, and 20- in the urban men were 1.42, 1.82, 2.22 in the control group I (trend test P < 0.01), and 1.57, 1.95, and 3.18 in the control group II (trend test P < 0.01).
Smoking is an important risk factor for mortality from EC in China. Investigating the surviving spouses of the deceased patients is a creative, effective, and feasible trial, with the prerequisite of whole population-based survey, in study of the main types of death and the relevant risk factors.
探讨吸烟与食管癌（EC）风险之间的关系，并提出在基于人群的病例对照研究中进行对照选择的理论框架，该研究已纳入中国全国范围的死亡率回顾性调查。
一项大规模的基于人群的病例对照研究纳入了1989 - 1991年进行的全国死亡率回顾性调查。通过非随机抽样选取了24个城市，并在1973 - 1975年癌症分布调查涵盖的3000个县中随机抽取了79个农村县。通过家访进行问卷调查，调查1986 - 1988年期间年龄≥35岁死于食管癌的19734名成年男性死者的死因和吸烟史。设立两个对照组，通过家访进行问卷调查，以调查死者及其 informant 的吸烟史。对照组I包括1986 - 1988年期间年龄≥35岁死于非恶性消化系统疾病的31989名成年男性的在世配偶或其他 informant，对照组II包括1986 - 1989年期间年龄≥35岁死于不同原因的成年女性死者的104846名男性配偶。使用非条件逻辑模型计算EC的相对风险和人群吸烟归因风险，并比较使用两个不同对照组进行分析的结果的一致性。
在所有城乡地区组中，吸烟者的EC绝对死亡率均高于非吸烟者。对照组I中，城市地区每1000名非吸烟者与吸烟者中的EC总绝对死亡率分别为0.37:0.65，内陆农村地区为0.99:1.29，沿海农村地区为1.09:1.62，对照组II也有类似趋势。吸烟时间与EC死亡风险以及每日吸烟量与EC死亡风险之间存在显著的剂量反应关系。例如，城市男性中，对照组I中每日吸烟<10支、10 - 支和20 - 支的风险比分别为1.42、1.82、2.22（趋势检验P<0.01），对照组II中分别为1.57、1.95和3.18（趋势检验P<0.01）。
吸烟是中国EC死亡的重要危险因素。在研究主要死亡类型及相关危险因素时，调查死者的在世配偶是一项有创造性、有效且可行的尝试，前提是基于全人群的调查。
