Sturgeon S R, Schairer C, Gail M, McAdams M, Brinton L A, Hoover R N
Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
J Natl Cancer Inst. 1995 Dec 20;87(24):1846-53. doi: 10.1093/jnci/87.24.1846.
For several decades, mortality from breast cancer has been higher in the northeastern part of the United States than in other regions, particularly the South. Rates have also been somewhat higher in the Midwest and West than in the South, especially among older women. The reasons for these geographic variations are not well understood.
The objective of this study was to evaluate geographic differences in U.S. breast cancer mortality rates in 1987, after taking into account regional differences in the distribution of recognized breast cancer risk factors (e.g., late age at first live birth) and certain prognostic factors (e.g., mammography use).
The 1987 breast cancer mortality rates for four regions of the country were obtained from the National Center for Health Statistics. Regional data on the distribution of breast cancer risk factors were obtained from 1987 National Health Interview Cancer Epidemiology Supplement interviews with 9778 white women aged 20-79 years. Regional data on the distribution of mammography use were obtained from 1987 National Health Interview Cancer Control Supplement interviews with 3795 white women aged 50-79 years.
Age-adjusted mortality ratios (MRs) among women 50 years and older were 1.15, 1.18, and 1.30 in the West, Midwest, and Northeast, respectively, compared with the South. Corresponding MRs among women 20-49 years old were 1.01, 1.08, and 1.07 in the West, Midwest, and Northeast, respectively, compared with the South. After adjustment for recognized risk factors and certain prognostic factors, MRs among older women were 1.13 (95% confidence interval [CI] = 1.04-1.23), 1.08 (95% CI = 1.01-1.16), and 1.13 (95% CI = 1.04-1.23) in the West, Midwest, and Northeast, respectively, compared with the South. Corresponding MRs among younger women were 0.94 (95% CI = 0.76-1.16), 1.05 (95% CI = 0.92-1.18), and 0.99 (95% CI = 0.86-1.14), respectively.
Before adjustment for regional differences in recognized risk factors and prognostic factors, mortality excesses among younger women in the Northeast, Midwest, and West were less than 10% compared with the South. After adjustment, MRs were near unity for all regions. Among older women, the excess mortality was more substantial before adjustment for relevant factors, ranging from 15% in the West to 30% in the Northeast. Approximately 50% of the excesses in the Northeast and Midwest and 10% of the excess in the West could be explained on the basis of regional differences in the prevalence of recognized breast cancer risk factors and prognostic factors. After adjustment for these factors, the magnitude of excess in breast cancer mortality in the Northeast (13%) was comparable to that in the West (13%) but still slightly higher than that in the Midwest (8%).
几十年来，美国东北部乳腺癌死亡率一直高于其他地区，尤其是南部地区。中西部和西部的死亡率也略高于南部，特别是在老年女性中。这些地理差异的原因尚不清楚。
本研究的目的是在考虑公认的乳腺癌危险因素（如首次生育年龄较晚）和某些预后因素（如乳房X光检查的使用）分布的区域差异后，评估1987年美国乳腺癌死亡率的地理差异。
从国家卫生统计中心获取该国四个地区1987年的乳腺癌死亡率。乳腺癌危险因素分布的区域数据来自1987年对9778名20 - 79岁白人女性进行的国家健康访谈癌症流行病学补充访谈。乳房X光检查使用分布的区域数据来自1987年对3795名50 - 79岁白人女性进行的国家健康访谈癌症控制补充访谈。
与南部相比，50岁及以上女性的年龄调整死亡率比（MRs）在西部、中西部和东北部分别为1.15、1.18和1.30。20 - 49岁女性相应的MRs在西部、中西部和东北部分别为1.01、1.08和1.07，与南部相比。在调整公认的危险因素和某些预后因素后，与南部相比，老年女性的MRs在西部、中西部和东北部分别为1.13（95%置信区间[CI]=1.04 - 1.23）、1.08（95% CI = 1.01 - 1.16）和1.13（95% CI = 1.04 - 1.23）。年轻女性相应的MRs分别为0.94（95% CI = 0.76 - 1.16）、1.05（95% CI = 0.92 - 1.18）和0.99（95% CI = 0.86 - 1.14）。
在调整公认危险因素和预后因素的区域差异之前，与南部相比，东北部、中西部和西部年轻女性的死亡率超额不到10%。调整后，所有地区的MRs接近1。在老年女性中，在调整相关因素之前，超额死亡率更高，从西部的15%到东北部的30%不等。东北部和中西部约50%的超额死亡率以及西部10%的超额死亡率可以根据公认的乳腺癌危险因素和预后因素患病率的区域差异来解释。在调整这些因素后，东北部乳腺癌死亡率的超额幅度（13%）与西部（13%）相当，但仍略高于中西部（8%）。
