Touvier Mathilde, Kesse Emmanuelle, Clavel-Chapelon Françoise, Boutron-Ruault Marie-Christine
INSERM, Equipe E3N, Institut Gustave Roussy, 94805 Villejuif Cedex, France.
J Natl Cancer Inst. 2005 Sep 21;97(18):1338-44. doi: 10.1093/jnci/dji276.
Intervention studies have demonstrated that, in smokers, beta-carotene supplements had a deleterious effect on risk of lung cancer and may have a deleterious effect on digestive cancers as well. We investigated a potential interaction between beta-carotene intake and smoking on the risk of tobacco-related cancers in women.
A total of 59,910 women from the French Etude Epidémiologique de Femmes de la Mutuelle Générale de l'Education Nationale (E3N) prospective investigation were studied from 1994. After a median follow-up of 7.4 years, 700 women had developed cancers known to be associated with smoking. Diet, supplement use, and smoking status at baseline were assessed by self-report. beta-carotene intake was classified into four groups: first (low intake), second, and third tertiles of dietary intake, and use of supplements (high intake). Unadjusted and multivariable Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals (CIs) for cancer risk. All statistical tests were two-sided.
Among never smokers, multivariable hazard ratios of all smoking-related cancers were 0.72 (95% CI = 0.57 to 0.92), 0.80 (95% CI = 0.64 to 1.01), and 0.44 (95% CI = 0.18 to 1.07) for the second and third tertiles of dietary intake, and high beta-carotene intake, respectively, compared with low intake (Ptrend = .03). Among ever smokers, multivariable hazard ratios were 1.43 (95% CI = 1.05 to 1.96), 1.20 (95% CI = 0.86 to 1.67), and 2.14 (95% CI = 1.16 to 3.97) for the second and third tertiles of dietary intake, and high beta-carotene intake, respectively, compared with low intake (Ptrend = .09). Tests for interaction between beta-carotene intake and smoking were statistically significant (Ptrend =.017). In this population, the absolute rates over 10 years in those with low and high beta-carotene intake were 181.8 and 81.7 cases per 10,000 women in never smokers and 174.0 and 368.3 cases per 10,000 women in ever smokers.
beta-carotene intake was inversely associated with risk of tobacco-related cancers among nonsmokers with a statistically significant dose-dependent relationship, whereas high beta-carotene intake was directly associated with risk among smokers.
干预研究表明，在吸烟者中，补充β-胡萝卜素对肺癌风险有有害影响，对消化道癌症可能也有有害影响。我们调查了β-胡萝卜素摄入量与吸烟之间潜在的相互作用对女性烟草相关癌症风险的影响。
自1994年起，对法国国家教育互助总会女性流行病学研究（E3N）前瞻性调查中的59910名女性进行了研究。经过7.4年的中位随访，700名女性患了已知与吸烟相关的癌症。通过自我报告评估基线时的饮食、补充剂使用情况和吸烟状况。β-胡萝卜素摄入量分为四组：第一组（低摄入量）、第二和第三三分位数的饮食摄入量以及补充剂使用情况（高摄入量）。使用未调整和多变量Cox比例风险模型计算癌症风险的风险比和95%置信区间（CI）。所有统计检验均为双侧检验。
在从不吸烟者中，与低摄入量相比，饮食摄入量的第二和第三三分位数以及高β-胡萝卜素摄入量的所有吸烟相关癌症的多变量风险比分别为0.72（95%CI = 0.57至0.92）、0.80（95%CI = 0.64至1.01）和0.44（95%CI = 0.18至1.07）（P趋势 = 0.03）。在曾经吸烟者中，与低摄入量相比，饮食摄入量的第二和第三三分位数以及高β-胡萝卜素摄入量的多变量风险比分别为1.43（95%CI = 1.05至1.96）、1.20（95%CI = 0.86至1.67）和2.14（95%CI = 1.16至3.97）（P趋势 = 0.09）。β-胡萝卜素摄入量与吸烟之间的相互作用检验具有统计学意义（P趋势 = 0.017）。在该人群中，低β-胡萝卜素摄入量和高β-胡萝卜素摄入量者每10年的绝对发病率在从不吸烟者中分别为每10000名女性181.8例和81.7例，在曾经吸烟者中分别为每10000名女性174.0例和368.3例。
在不吸烟者中，β-胡萝卜素摄入量与烟草相关癌症风险呈负相关，且具有统计学意义的剂量依赖性关系，而在吸烟者中，高β-胡萝卜素摄入量与风险呈正相关。
