Day Gretchen Ehrsam, Lanier Anne P, Bulkow Lisa, Kelly Janet J, Murphy Neil
Office of Alaska Native Health Research, Division of Community Health Services, Alaska Native Tribal Health Consortium, Anchorage, AK 99508, USA.
Int J Circumpolar Health. 2010 Feb;69(1):72-86. doi: 10.3402/ijch.v69i1.17388.
Alaska Native (AN) women have exhibited some of the highest incidence rates of cancer overall, and different patterns of site-specific incidence compared to other U.S. populations. This study compares incidence rates between AN and U.S. white women (USW) for cancers of the breast, uterus, ovary and cervix, and examines effects of time period and birth cohort as determinants of incidence trends among AN women.
Observational, population-based study.
Cancer incidence data from the Alaska Native Tumor Registry and SEERStat, 1974-2003. Age-adjusted World Standard Population rates were calculated for a current 5-year period and over time (30 years), and compared to other populations using rate ratios with 95% confidence intervals. Log-linear regression models used to assess impact on trend of age, time period and birth cohort.
Compared to U.S. white women, current cancer rates among AN women are not significantly different for cancer of the breast and cervix, and significantly lower for cancers of the ovary and uterus. Trends over time over a 30-year time period also differ for these cancer sites. There were significant increases in breast and uterine cancer, and in contrast, a marked decline in cervical cancer. There was no significant change for cancer of the ovary. Changes appear to be due largely to period, not birth cohort effects.
Increases in breast cancer may be due to a combination of modifiable behaviours; increased BMI and a shift to a non-traditional diet. Increases in uterine cancer could be associated with increased BMI and diabetes. Cervical cancer rates have declined to USW levels. The marked decline is likely due to enhanced screening and control efforts within the Alaska Native Women's cancers among Alaska Natives Tribal Health System (formerly Alaska Area USPHS, Indian Health Service utilizing resources available from the Centers for Disease Control tribal and state Breast and Cervical Cancer Early Detection Programs).
阿拉斯加原住民（AN）女性总体上呈现出一些最高的癌症发病率，并且与其他美国人群相比，特定部位的发病率模式有所不同。本研究比较了AN女性和美国白人女性（USW）在乳腺癌、子宫癌、卵巢癌和宫颈癌方面的发病率，并研究时间段和出生队列作为AN女性发病率趋势决定因素的影响。
基于人群的观察性研究。
来自阿拉斯加原住民肿瘤登记处和SEERStat的1974 - 2003年癌症发病率数据。计算了当前5年期间及30年时间跨度的年龄调整世界标准人口率，并使用95%置信区间的率比与其他人群进行比较。使用对数线性回归模型评估年龄、时间段和出生队列对趋势的影响。
与美国白人女性相比，AN女性目前的乳腺癌和宫颈癌发病率无显著差异，卵巢癌和子宫癌发病率显著较低。这些癌症部位在30年时间跨度内随时间的趋势也有所不同。乳腺癌和子宫癌发病率显著上升，相比之下，宫颈癌显著下降。卵巢癌发病率无显著变化。变化似乎主要归因于时间段，而非出生队列效应。
乳腺癌发病率上升可能是由于多种可改变行为的综合作用；体重指数增加以及向非传统饮食的转变。子宫癌发病率上升可能与体重指数增加和糖尿病有关。宫颈癌发病率已降至美国白人女性的水平。显著下降可能是由于阿拉斯加原住民部落卫生系统（原阿拉斯加地区美国公共卫生服务局，现印第安卫生服务局利用疾病控制中心部落和州乳腺癌及宫颈癌早期检测项目提供的资源）对阿拉斯加原住民女性癌症加强了筛查和控制力度。
