MHSc, Cancer Control Policy, Canadian Cancer Society, 10 Alcorn Ave, Ste 200, Toronto, ON, Canada M4V 3B1.
J Natl Cancer Inst. 2010 Oct 6;102(19):1489-95. doi: 10.1093/jnci/djq345. Epub 2010 Sep 23.
In 2002, results of the Women's Health Initiative clinical trial indicated that the long-term risks of combined estrogen and progestin hormone replacement therapy outweighed the health benefits for postmenopausal women. The resulting decline in use of hormone replacement therapy was followed by concurrent decreases in breast cancer incidence in several countries. The aim of the current study was to determine whether similar declines occurred in Canada.
Data on prescriptions for hormone therapy were obtained from a national registry of pharmacy-filled prescriptions to confirm the reported trend in use of hormone replacement therapy among approximately 1200 women aged 50-69 years who participated in the National Population Health Survey between 1996 and 2006 and whose data were extrapolated to the Canadian female population. Age-standardized incidence rates for breast cancer were obtained from the population-based Canadian Cancer Registry for the same period, and mammography rates were obtained from the Canadian Community Health Survey. Joinpoint regression was used to examine changes in trends in the use of hormone replacement therapy and breast cancer incidence.
A reduced frequency of use of hormone replacement therapy was reflected in the decrease in dispensed hormone therapy prescriptions after 2002. The largest drop in use of combined hormone replacement therapy (from 12.7%, 95% confidence interval [CI] = 10.1% to 14.2%, to 4.9%, 95% CI = 3.4% to 6.8%, of all women) occurred between January 1, 2002, and December 31, 2004, among women aged 50-69 years. This drop occurred concurrently with a 9.6% decline in the incidence rate of breast cancer (from 296.3 per 100,000 women, 95% CI = 290.8 to 300.5 per 100,000 women, in 2002 to 268.0 per 100,000 women, 95% CI = 263.3 to 273.5 per 100,000 women, in 2004). Mammography rates were stable at 72% over the same period.
During the period 2002-2004, there was a link between the declines in the use of hormone replacement therapy and breast cancer incidence among Canadian women aged 50-69 years, in the absence of any change in mammography rates.
2002 年，女性健康倡议临床试验的结果表明，长期使用雌激素和孕激素联合激素替代疗法的风险超过了绝经后妇女的健康益处。随后，几个国家的乳腺癌发病率也随之下降。本研究旨在确定加拿大是否也出现了类似的下降。
通过国家药房配药记录获取激素治疗处方数据，以确认报告中 2002 年前后 1200 名 50-69 岁女性使用激素替代疗法的趋势，这些女性参加了 1996 年至 2006 年期间的全国人口健康调查，并将数据外推至加拿大女性人口。同期从基于人群的加拿大癌症登记处获取乳腺癌发病率的年龄标准化发病率数据，并从加拿大社区健康调查获取乳房 X 线照相率数据。使用 Joinpoint 回归检验激素替代疗法使用和乳腺癌发病率趋势的变化。
2002 年后，激素治疗处方的减少反映了激素替代疗法使用频率的降低。联合激素替代疗法的使用量下降最大（从所有女性的 12.7%（95%置信区间[CI]为 10.1%至 14.2%）降至 4.9%（95%CI 为 3.4%至 6.8%）），发生在 2002 年 1 月 1 日至 2004 年 12 月 31 日之间，年龄在 50-69 岁的女性中。这种下降与乳腺癌发病率下降 9.6%同时发生（从 2002 年的每 10 万名妇女 296.3 例（95%CI 为 290.8 至 300.5 例）降至 2004 年的每 10 万名妇女 268.0 例（95%CI 为 263.3 至 273.5 例））。同期乳房 X 线照相率保持在 72%的稳定水平。
在 2002-2004 年期间，加拿大 50-69 岁女性中激素替代疗法的使用减少与乳腺癌发病率之间存在关联，而乳房 X 线照相率没有任何变化。
