Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii, 1236 Lauhala Street, Honolulu, HI 96813, USA.
Cancer Epidemiol Biomarkers Prev. 2010 Jan;19(1):130-4. doi: 10.1158/1055-9965.EPI-09-0475.
Vitamin D is obtained from the diet and synthesized in skin exposed to sunlight. Vitamin D status, assessed by circulating 25-hydroxyvitamin D [25(OH)D], has been associated with a reduced risk of colorectal cancer in previous studies. To complement existing evidence, we conducted a case-control study nested within the Multiethnic Cohort including men and women of Japanese, Latino, African-American, White, and Native Hawaiian ancestry. Using a direct competitive chemiluminescence immunoassay, 25(OH)D level was determined in plasma drawn before diagnosis from 229 cases and 434 controls matched to cases by area (Hawaii, Los Angeles), sex, ethnicity, birth year, blood draw date and time, and hours fasting. Odds ratios (OR) were estimated with conditional logistic regression. An inverse trend was observed (OR per doubling of 25(OH)D, 0.68; 95% confidence interval, 0.51-0.92; P = 0.01), but when examined in categories, relative to the first quintile (<16.8 ng/mL), the ORs in all other quintiles were quite similarly reduced between 37% and 46%. The association was not significantly heterogeneous among the four largest ethnic groups (P(heterogeneity) = 0.46). In summary, this study provides evidence of an association between vitamin D status and reduced risk of colorectal cancer in an ethnically diverse population.
维生素 D 可通过饮食摄取，也可在皮肤暴露于阳光下时合成。以前的研究表明，通过检测循环 25-羟维生素 D[25(OH)D]来评估维生素 D 状况与结直肠癌风险降低有关。为了补充现有证据，我们在包括日裔、拉丁裔、非裔美国人、白人和夏威夷原住民血统的男性和女性的多民族队列中进行了一项病例对照研究，该研究嵌套在队列内。使用直接竞争化学发光免疫测定法，在诊断前从 229 例病例和 434 例与病例相匹配的对照者（按地区（夏威夷、洛杉矶）、性别、种族、出生年份、采血日期和时间以及禁食时间）的血浆中测定 25(OH)D 水平。使用条件逻辑回归估计比值比 (OR)。观察到呈反比趋势（每增加 25(OH)D 的倍数的 OR，0.68；95%置信区间，0.51-0.92；P=0.01），但在分类检查时，与第一五分位数（<16.8ng/mL）相比，所有其他五分位数的 OR 降低幅度在 37%至 46%之间相当。在四个最大的种族群体中，这种关联没有显著的异质性（P（异质性）=0.46）。总之，这项研究为在一个种族多样化的人群中维生素 D 状况与结直肠癌风险降低之间存在关联提供了证据。
