JNCI: Journal of the National Cancer Institute, 2012, 104(1):67-76.

Legume, Soy, Tofu, and Isoflavone Intake and Endometrial Cancer Risk in Postmenopausal Women in the Multiethnic Cohort Study

Nicholas J Ollberding, Unhee Lim, Lynne R Wilkens, et al

University of Hawaii Cancer Center, Epidemiology Program, Honolulu, HI 96813, USA

BACKGROUND:

Phytochemicals found in soy and other legumes have been speculated to reduce the risk of endometrial cancer; however, inconsistent findings have been reported in the few epidemiological studies conducted to date.

METHODS:

We conducted a prospective analysis of 46 027 nonhysterectomized postmenopausal women who were recruited into the Multiethnic Cohort (MEC) Study between August 1993 and August 1996 and provided detailed baseline information on diet and other endometrial cancer risk factors. A total of 489 women diagnosed with incident endometrial cancer were identified through the Surveillance, Epidemiology, and End Results tumor registry linkages during a median follow-up period of 13.6 years. Cox proportional hazards models were used to estimate multivariable-adjusted relative risks (RRs) and 95% confidence intervals (CIs) for endometrial cancer associated with dietary intake of legumes, soy, and tofu, and for total isoflavones and specific isoflavones (daidzein, genistein, or glycitein). Truncated (age 50-89 years) age-adjusted incidence rates were calculated by applying age-specific rates within isoflavone quintiles to the overall MEC population eligible for endometrial cancer. To estimate the percentage of endometrial cancers that may have been prevented by consuming the highest quintile of total isoflavones, the partial population attributable risk percent was calculated.

RESULTS:

A reduced risk of endometrial cancer was associated with total isoflavone intake (highest vs lowest quintile, ≥7.82 vs <1.59 mg per 1000 kcal/d, RR = 0.66, 95% CI = 0.47 to 0.91), daidzein intake (highest vs lowest quintile, ≥3.54 vs <0.70 mg per 1000 kcal/d, RR = 0.64, 95% CI = 0.46 to 0.90), and genistein intake (highest vs lowest quintile, ≥3.40 vs <0.69 mg per 1000 kcal/d, RR = 0.66, 95% CI = 0.47 to 0.91). No statistically significant association with endometrial cancer risk was observed for increasing intake of legumes, soy, tofu, or glycitein. Truncated age-adjusted incidence rates of endometrial cancer for the highest vs lowest quintile of total isoflavone intake were 55 vs 107 per 100 000 women per year, respectively. The partial population attributable risk percent for total isoflavone intake lower than the highest quintile was 26.7% (95% CI = 5.3% to 45.8%).

CONCLUSION:

This study suggests that greater consumption of isoflavone-containing foods is associated with a reduced risk of endometrial cancer in this population of nonhysterectomized postmenopausal women.

美国《国家癌症研究所杂志》，2012年1月

对绝经后妇女的豆类、 大豆、 豆腐，和异黄酮摄取量和子宫内膜癌风险的多民族研究

尼古拉斯  J 奥欧柏丁，恩黑 李，琳恩  R 威尔肯斯，等

美国夏威夷癌症中心大学流行病学项目

背景︰

在大豆和其他豆科植物中发现的植物化学物质被推测用来降低子宫内膜癌的风险；然而，迄今进行的流行病学研究极少报道不一致的结果。

方法︰

我们对在1993 年 8 月到 1996 年 8 月期间被招募到多种族队列 (MEC) 研究的46 027名没有切除子宫的绝经后妇女的进行了前瞻性分析并提供了饮食和其他子宫内膜癌风险因素详细的基线资料。在13.6 年的平均随访期间，通过监测、 流行病学和最终的肿瘤登记处确定了共有 489名妇女被诊断出患有子宫内膜癌症。Cox 比例风险模型被用来估计子宫内膜癌多变量调整的相对危险度 (Rr) 和与饮食摄入的豆类，大豆，豆腐，总异黄酮和特定的异黄酮 （大豆甙元、 金雀异黄素或黄豆黄素）等有关的95%可信区间 （独联体）。通过应用年龄-特定比率和异黄酮的五分位数相比于子宫内膜癌 MEC 总人口数计算截断 （年龄 50-89 岁） 龄期调整的发病率。为了估计被最高五分位数的总异黄酮消耗阻止的子宫内膜癌的百分比，计算部分人群归因风险百分比。

结果︰

子宫内膜癌的风险降低与总异黄酮摄取量 (最高vs最低的五分位数，≥7.82 vs < 1.59 mg 每1000 kcal/d，RR = 0.66，95 % CI= 0.47-0.91)，大豆黄酮摄入量 (最高vs最低的五分位数，≥3.54 vs < 0.70 mg / 1000 kcal/d，RR = 0.64，95 % CI= 0.46-0.90)，和金雀异黄素摄入量 (最高vs最低的五分位数，≥3.40 vs < 0.69 mg / 1000 kcal/d，RR = 0.66，95 % CI= 0.47-0.91)。没有观察到统计学意义的子宫内膜癌风险与提高豆类，大豆，豆腐，或者黄豆黄素的摄入量相关。子宫内膜癌截断的年龄调整最高发病率vs 总异黄酮摄取量最低的五分位数分别为每年 55 vs 107 每 100 000 名妇女。部分人群的归因危险百分数对于总异黄酮摄取量低于最高的五分位数，为26.7%(95 %CI= 5.3%至 45.8%)。