Department of Society, Human Development, and Health, Harvard School of Public Health, Boston, MA 02115, USA.
Cancer. 2010 Sep 1;116(17):4187-96. doi: 10.1002/cncr.25195.
Neighborhood amenities and resources plausibly determine individual modifiable risk factors for colon and rectal cancer. Evidence on the associations between neighborhood socioeconomic status (SES) and incident colon and rectal cancer is limited.
The authors analyzed a prospective cohort of 111,129 women in the Nurses' Health Study with no history of cancer in 1986 followed to 2006. Neighborhood SES was based on Census-derived characteristics of block groups of residence. Cox models were used to estimate the multivariate-adjusted associations between neighborhood SES and incident colon and rectal cancer, and to examine for effect modification. For significant associations, path models were estimated with behavioral risk factors included as potential mediators.
Neighborhood SES was unassociated with colon cancer among all women. However, among women with college or greater education, higher neighborhood SES was inversely related to colon cancer (P for trend = .01; P for interaction between neighborhood SES and education = .03). Path analysis suggested mediation by red meat intakes and body mass index (BMI). Higher neighborhood SES was inversely related to rectal cancer among all women (relative risk in highest quintile, 0.64; 95% confidence interval, 0.44-0.93; P for trend = .08). Path analysis was consistent with mediation by multivitamin use and BMI.
These findings suggest that living in a higher-SES neighborhood may protect against rectal cancer in women and colon cancer in higher-educated women, mediated by selected behavioral risk factors. Risk factor differences between colon and rectal cancer may account for discrepancies in estimated neighborhood effects by cancer site.
社区设施和资源可能会影响个体结肠癌和直肠癌的可改变风险因素。关于社区社会经济地位（SES）与结肠癌和直肠癌发病风险之间的关联，证据有限。
作者分析了 1986 年无癌症病史的 111129 名护士健康研究中的前瞻性队列，随访至 2006 年。社区 SES 基于居住的街区组的人口普查得出的特征。Cox 模型用于估计社区 SES 与结肠癌和直肠癌发病风险之间的多变量调整关联，并检验其修饰作用。对于显著关联，使用行为风险因素作为潜在的中介，估计路径模型。
社区 SES 与所有女性的结肠癌无关。然而，在受过大学或更高教育的女性中，较高的社区 SES 与结肠癌呈负相关（趋势 P 值=.01；SES 和教育之间的交互作用 P 值=.03）。路径分析表明，肉类摄入量和体重指数（BMI）起中介作用。SES 较高的社区与所有女性的直肠癌呈负相关（最高五分位数的相对风险，0.64；95%置信区间，0.44-0.93；趋势 P 值=.08）。路径分析与使用多种维生素和 BMI 作为中介一致。
这些发现表明，生活在 SES 较高的社区可能会降低女性患直肠癌和高学历女性患结肠癌的风险，其机制可能是通过选择行为风险因素。结肠癌和直肠癌之间的风险因素差异可能解释了按癌症部位估计的社区效应的差异。
