Steinmetz K A, Potter J D, Folsom A R
Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis 55454-1015.
Cancer Res. 1993 Feb 1;53(3):536-43.
Previous epidemiological studies have shown an inverse association between vegetable and fruit consumption and lung cancer risk; few of these studies have been prospective or have focused upon women. In 1986, we assessed food intake in 41,837 Iowa women, aged 55 to 69 yr, with a mailed 127-item food frequency questionnaire. After 4 years of follow-up, 179 incident cases of lung cancer were identified via the Iowa Surveillance, Epidemiology, and End Results cancer registry. After specific exclusion criteria were applied, a nested case-control comparison of 138 cases with 2,814 randomly selected noncases was undertaken. Intakes, in the upper-most quartile, of 11 vegetable and fruit groups, as well as of the nutrients beta-carotene and vitamin C, were explored. High intakes of all vegetables and fruit, all vegetables, and green leafy vegetables were each associated with an approximate halving of risk: age-, smoking-, and energy-adjusted odds ratios (ORs) were 0.49 (95% confidence interval, 0.28-0.86), 0.50 (95% confidence interval, 0.29-0.87), and 0.45 (95% confidence interval, 0.26-0.76), respectively. A lower lung cancer risk was also seen for all fruit (adjusted OR = 0.75 for high consumption), high vitamin C vegetables and fruit (OR = 0.75), carrots (OR = 0.71), and brocolli (OR = 0.72) and for the nutrients beta-carotene (OR = 0.81) and vitamin C (OR = 0.81) (all 95% confidence intervals included 1.0). Lung cancer risk was unrelated to consumption of the three food groups defined as "high-carotenoid" (beta-carotene, lutein, and lycopene) and tomatoes. In an analysis stratified by histological type of lung cancer, the strongest inverse associations for vegetables and fruit were seen for large cell carcinoma. Analysis by smoking status showed the inverse associations for most vegetable and fruit groups with lung cancer risk to be stronger for exsmokers than for current smokers. Results from the stratified analyses must be interpreted with caution because of the small number of cases in each stratum.
以往的流行病学研究表明，蔬菜和水果的摄入量与肺癌风险呈负相关；但这些研究中很少有前瞻性研究，也很少有针对女性的研究。1986年，我们通过邮寄一份包含127个条目的食物频率问卷，对41837名年龄在55至69岁之间的爱荷华州女性的食物摄入量进行了评估。经过4年的随访，通过爱荷华州癌症监测、流行病学和最终结果癌症登记处确定了179例肺癌新发病例。在应用特定的排除标准后，对138例病例与2814例随机选择的非病例进行了巢式病例对照比较。探讨了11种蔬菜和水果组以及营养素β-胡萝卜素和维生素C摄入量处于最高四分位数的情况。所有蔬菜和水果、所有蔬菜以及绿叶蔬菜的高摄入量均与风险降低约一半相关：年龄、吸烟和能量调整后的比值比（OR）分别为0.49（95%置信区间，0.28 - 0.86）、0.50（95%置信区间，0.29 - 0.87）和0.45（95%置信区间，0.26 - 0.76）。所有水果（高摄入量时调整后的OR = 0.75）、高维生素C的蔬菜和水果（OR = 0.75）、胡萝卜（OR = 0.71）、西兰花（OR = 0.72）以及营养素β-胡萝卜素（OR = 0.81）和维生素C（OR = 0.81）也显示出较低的肺癌风险（所有95%置信区间均包含1.0）。肺癌风险与定义为“高类胡萝卜素”（β-胡萝卜素、叶黄素和番茄红素）的三个食物组以及番茄的摄入量无关。在按肺癌组织学类型分层的分析中，蔬菜和水果与大细胞癌的负相关最强。按吸烟状况分析表明，大多数蔬菜和水果组与肺癌风险的负相关在既往吸烟者中比在当前吸烟者中更强。由于每个分层中的病例数量较少，分层分析的结果必须谨慎解释。
