Lea C Suzanne, Gordon Nancy P, Prebil Lee Ann, Ereman Rochelle, Uratsu Connie S, Powell Mark
Department of Public Health, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
BMC Womens Health. 2009 Mar 25;9:6. doi: 10.1186/1472-6874-9-6.
The Northern California county of Marin (MC) has historically had high breast cancer incidence rates. Because of MC's high socioeconomic status (SES) and racial homogeneity (non-Hispanic White), it has been difficult to assess whether these elevated rates result from a combination of established risk factors or other behavioral or environmental factors. This survey was designed to compare potential breast cancer risks and incidence rates for a sample of middle-aged MC women with those of a demographically similar population.
A random sample of 1500 middle-aged female members of a large Northern California health plan, half from Marin County (MC) and half from a comparison area in East/Central Contra Costa County (ECCC), were mailed a survey covering family history, reproductive history, use of oral contraceptives (OC) and hormone replacement therapy (HRT), behavioral health risks, recency of breast screening, and demographic characteristics. Weighted data were used to compare prevalence of individual breast cancer risk factors and Gail scores. Age-adjusted cumulative breast cancer incidence rates (2000-2004) were also calculated for female health plan members aged 40-64 residing in the two geographic areas.
Survey response was 57.1% (n = 427) and 47.9% (n = 359) for MC and ECCC samples, respectively. Women in the two areas were similar in SES, race, obesity, exercise frequency, current smoking, ever use of OCs and HRT, age at onset of menarche, high mammography rates, family history of breast cancer, and Gail scores. However, MC women were significantly more likely than ECCC women to be former smokers (43.6% vs. 31.2%), have Ashkenazi Jewish heritage (12.8% vs. 7.1%), have no live births before age 30 (52.7% vs. 40.8%), and be nulliparous (29.2% vs. 15.4%), and less likely to never or rarely consume alcohol (34.4% vs. 41.9%). MC and ECCC women had comparable 2000-2004 invasive breast cancer incidence rates.
The effects of reproductive risks factors, Ashkenazi Jewish heritage, smoking history, and alcohol consumption with regard to breast cancer risk in Marin County should be further evaluated. When possible, future comparisons of breast cancer incidence rates between regions should adjust for differences in income and education in addition to age and race/ethnicity, preferably by using a sociodemographically similar comparison group.
北加利福尼亚州的马林县（MC）历来乳腺癌发病率较高。由于马林县社会经济地位（SES）高且种族同质化（非西班牙裔白人），很难评估这些升高的发病率是由既定风险因素的组合还是其他行为或环境因素导致的。本调查旨在比较马林县中年女性样本与人口统计学特征相似人群的潜在乳腺癌风险和发病率。
向北加利福尼亚州一个大型健康计划的1500名中年女性成员随机抽样，其中一半来自马林县（MC），另一半来自东/中康特拉科斯塔县（ECCC）的一个对照区域，邮寄了一份涵盖家族史、生殖史、口服避孕药（OC）和激素替代疗法（HRT）的使用、行为健康风险、乳房筛查近期情况以及人口统计学特征的调查问卷。加权数据用于比较个体乳腺癌风险因素的患病率和盖尔评分。还计算了居住在这两个地理区域的40 - 64岁女性健康计划成员2000 - 2004年的年龄调整累积乳腺癌发病率。
马林县和东/中康特拉科斯塔县样本的调查回复率分别为57.1%（n = 427）和47.9%（n = 359）。两个地区的女性在社会经济地位、种族、肥胖、运动频率、当前吸烟情况、曾经使用口服避孕药和激素替代疗法、初潮年龄、高乳腺X线摄影率、乳腺癌家族史和盖尔评分方面相似。然而，马林县女性比东/中康特拉科斯塔县女性更有可能是既往吸烟者（43.6%对31.2%）、有阿什肯纳兹犹太血统（12.8%对7.1%）、30岁前无活产（52.7%对40.8%）且未生育（29.2%对15.4%），而从不或很少饮酒的可能性较小（34.4%对41.9%）。马林县和东/中康特拉科斯塔县女性2000 - 2004年浸润性乳腺癌发病率相当。
应进一步评估生殖风险因素、阿什肯纳兹犹太血统、吸烟史和饮酒对马林县乳腺癌风险的影响。未来在可能的情况下，地区间乳腺癌发病率的比较除了年龄和种族/族裔外，还应调整收入和教育差异，最好使用社会人口统计学特征相似的对照组。
