Alavanja M C, Brown C C, Swanson C, Brownson R C
Division of Cancer Etiology, National Cancer Institute, Rockville, Md. 20852.
J Natl Cancer Inst. 1993 Dec 1;85(23):1906-16. doi: 10.1093/jnci/85.23.1906.
Although the vast majority of lung cancer cases in women are caused by smoking, 9%-20% of cases occur in nonsmokers. Previous epidemiologic research on the relationship between lung cancer and diet has shown that fruit and vegetable consumption may confer a protective effect against lung cancer, while a diet rich in cholesterol and fat may increase risk.
The purpose of this case-control study was to examine the effects of a broad range of dietary factors on the risk of lung cancer in a population of nonsmoking white women 30-84 years of age.
A telephone-administered questionnaire was used to determine and/or verify eligibility with regard to age, gender, race, and smoking status. In a second interview at the participant's home, a widely used food frequency questionnaire was filled out, and logistic regression was subsequently used to analyze the responses. We obtained dietary information on 429 case subjects who had a diagnosis of lung cancer reported to the Missouri Cancer Registry between June 1, 1986, and June 1, 1991, and 1021 control subjects. If a case subject had died or was too ill to be interviewed, next-of-kin familiar with the woman's diet were interviewed instead. Of the 429 women with lung cancer, 211 (49%) had lung adenocarcinoma.
A strongly increasing trend in lung cancer risk was observed with increased saturated fat consumption among these non-smoking women; the relative risk was more than sixfold greater for the highest quintile of consumption than for the lowest quintile. The effect of saturated fat was more pronounced for adenocarcinoma than for other cell types. Weekly servings of beans and peas were significantly related to decreased lung cancer risk, while citrus fruit and juice showed a twofold increase in risk; this trend was also significant.
By focusing on non-smoking women with lung cancer, including a large number with adenocarcinoma, we observed a clear association with saturated fat consumption that may have been masked in earlier studies of lung cancer involving a high percentage of smokers.
尽管女性肺癌病例绝大多数由吸烟所致，但9% - 20%的病例发生在不吸烟者中。先前关于肺癌与饮食关系的流行病学研究表明，食用水果和蔬菜可能对肺癌具有保护作用，而富含胆固醇和脂肪的饮食可能会增加患病风险。
本病例对照研究的目的是在30 - 84岁的非吸烟白人女性人群中，检验多种饮食因素对肺癌风险的影响。
通过电话问卷调查来确定和/或核实年龄、性别、种族及吸烟状况是否符合要求。在参与者家中进行的第二次访谈中，填写一份广泛使用的食物频率问卷，随后使用逻辑回归分析问卷回复。我们获取了1986年6月1日至1991年6月1日期间向密苏里州癌症登记处报告确诊为肺癌的429例病例受试者以及1021例对照受试者的饮食信息。如果病例受试者已死亡或病情过重无法接受访谈，则采访熟悉该女性饮食情况的近亲。在429例肺癌女性患者中，211例（49%）患有肺腺癌。
在这些非吸烟女性中，随着饱和脂肪摄入量增加，观察到肺癌风险呈显著上升趋势；摄入量最高五分位数人群的相对风险比最低五分位数人群高出六倍多。饱和脂肪对腺癌的影响比对其他细胞类型更为明显。每周食用豆类与降低肺癌风险显著相关，而柑橘类水果和果汁的风险则增加了两倍；这一趋势也很显著。
通过聚焦于患有肺癌的非吸烟女性，包括大量患有腺癌的女性，我们观察到饱和脂肪摄入量与之存在明显关联，而这一关联在早期涉及高比例吸烟者的肺癌研究中可能被掩盖了。
