Axelsson G, Liljeqvist T, Andersson L, Bergman B, Rylander R
Department of Environmental Medicine. Göteborg University, Gothenburg, Sweden.
Int J Epidemiol. 1996 Feb;25(1):32-9. doi: 10.1093/ije/25.1.32.
Previous studies have reported an association between tea drinking and lung cancer. In view of these data, the relationship between tea drinking as well as other dietary factors and lung cancer was investigated in a case-control study in the west of Sweden.
Patients with suspected lung cancer were collected from pulmonary units at central hospitals in the area investigated, and population controls were matched for age. The material reported here comprises 308 male cases with a confirmed diagnosis of lung cancer and 504 controls. The participants were interviewed by specially trained nurses, using a questionnaire to assess smoking, dietary habits, occupational exposures and conditions in the residential area (local air pollution). This paper reports the results from dietary factors studied with a food frequency technique.
The results demonstrated a strong protective effect of vegetables (odds ratio [OR] = 0.69, 95% confidence interval [CI]: 0.46-1.05, and OR = 0.37, 95% CI: 0.23-0.61 for intermediate and high consumption classes respectively). A low OR was consistent for all histological types of lung cancer. High consumption of fruits did not show any similar protective effect. Drinking milk was associated with a dose-response related risk increase after adjustment for smoking and vegetable consumption (P for trend = 0.07). Odds ratio was 1.73, 95% CI: 1.00-3.01 for high consumption of milk.
High intake of vegetables had a strong protective effect among males. Diet is thus a potential confounding factor in studies on lung cancer and environmental factors and should thus be taken into consideration in the planning of such studies.
既往研究报道了饮茶与肺癌之间的关联。鉴于这些数据，在瑞典西部进行的一项病例对照研究中，对饮茶以及其他饮食因素与肺癌之间的关系进行了调查。
从所调查地区中心医院的肺部科室收集疑似肺癌患者，并为年龄匹配的人群设置对照。本文报道的研究对象包括308例确诊为肺癌的男性病例和504例对照。由经过专门培训的护士对参与者进行访谈，使用问卷评估吸烟情况、饮食习惯、职业暴露以及居住地区的状况（当地空气污染）。本文报告了采用食物频率技术研究饮食因素的结果。
结果显示蔬菜具有很强的保护作用（比值比[OR]=0.69，95%置信区间[CI]：0.46 - 1.05，中等和高消费类别分别为OR = 0.37，95% CI：0.23 - 0.61）。对于所有组织学类型的肺癌，低OR值均一致。高水果摄入量未显示出任何类似的保护作用。在调整吸烟和蔬菜摄入量后，饮用牛奶与剂量反应相关的风险增加有关（趋势P值=0.07）。牛奶高摄入量的比值比为1.73，95% CI：1.00 - 3.01。
高蔬菜摄入量对男性具有很强的保护作用。因此，饮食是肺癌与环境因素研究中的一个潜在混杂因素，在这类研究的规划中应予以考虑。
