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Society of Obstetricians and Gynaecologists of Canada responds to recent studies on hormone replacement therapy
' ' '
L E T T E R S
TO
T H E
To THE EDITOR:
' ' '
The Nurses' Health Study on HRT and breast cancer, published in the New England Journal of Medicine on June 15, 1995, reported an increased incidence of breast cancer in current users of estrogen replacement therapy, with or without progestin. A Seattle study comparing women with and without breast cancer, which showed completely different results, was published in the Journal of the American Medical Association (JAMA). The study failed to find any increased risk of breast cancer associated with either current or long-term use of estrogen-progestin HRT. Although the Seattle study is reassuring, it is one of the many (now over 40) population-based case-control studies, and is therefore, a retrospective review of the issues. This report included the histories of 1,029 Washington State women. Five hundred and thirty-seven women who had breast cancer between] anuary 1989 and June 1990 were randomly selected from the SeattlePuget Sound Cancer Registry. Another 492 women without a breast cancer history were randomly selected as controls. Both estrogen alone and combined with progestin use were examined in this report and did not appear to be associated with an increased risk of breast cancer in older women. The Nurses' Health Study, also an observational, casecontrol study, included almost 70,000 women between 1976 and 1992, and reported on 1,935 breast cancer cases diagnosed and 359 breast cancer deaths. This work suggests that there is an increased relative risk among longterm and current users of estrogen (a 32 percent increase for estrogen use alone and a 41 percent increase for combination therapy of estrogen and progestin). This study, which involved a large patient population and highly regarded investigators, must be given credibility. "Because of the protective effects HRT has against cardiovascular disease (the leading cause of death for Canadian women) and because of the strong protective effect against osteoporosis, we believe it is important that physicians and patients not draw premature conclusions from these studies," said Dr. Jolly. Hormone Replacement Therapy has been shown to reduce the risk of heart disease by 50 percent and to reduce the incidence of osteoporosis by 50 percent.
The appearance of two recent reports which examined the relationship between Hormone Replacement Therapy and breast cancer has given rise to a great deal of public concern. To address these concerns, the SOGC has evaluated these reports and has adopted a position which was communicated to the public. Because of the urgency of the issue, and to alleviate controversy and reassure Canadian women, a press release was issued on July 18, 1995. I would request that as a service to our members and readership an edited version of the release, which outlines the position of the SOGC, be published in the letters to the editor column. Yours sincerely, A.B. Lalonde, MD, FRCSC Executive Vice-President SOCIETY OF OBSTETRICIANS AND GYNAECOLOGISTS OF CANADA RESPONDS TO RECENT STUDIES ON HoRMONE REPLACEMENT THERAPY
Two recently published medical studies on the use of hormone replacement therapy (HRT) and breast cancer have generated significant public attention. In light of these studies, which had contradictory results, the Society of Obstetricians and Gynaecologists of Canada (SOGC) has met to discuss these findings and to reaffirm its position that women should assess their individual risk versus the benefits of HRT. "The release of these two studies in such a short time frame really highlights how important it is for the public to take such studies in stride and not to be reactive. Each new study provides that much more depth of understanding to physicians when discussing the appropriateness of HRT with their patients," said Dr. Elaine Jolly, Director of Menopause Clinic at the Ottawa General Hospital and Chair of the SOGC's Special Interest Group on Menopause and Aging. The Society's Special Interest Group believes strongly that the findings of the Nurses' Health Study and the new Seattle study need to be put into context for women who are taking or are considering taking HRT and for physicians treating menopausal patients.
JOURNAL SOGC
EDITOR
955
OCTOBER 1995
' ' ' Annually in Canada, there are some 40,000 deaths from myocardial infarction and some 100,000 osteoporotic fractures (approximately 20,000 of these are hip fractures). Twelve to 20 percent of women who sustain hip fractures will die within six months. There are approximately 3,900 deaths from breast cancer per year. The mortality from heart attack and osteoporotic fractures is, therefore, 10 times greater than that for breast cancer. The SOGC, however, does recognize the very real concern of women and their fear of developing breast cancer. The importance of careful monitoring, breast self-examination, routine mammograms, and physician assessments cannot be overemphasized. But there has been some misunderstanding of the statistics by physicians and patients as to what the percent increases really mean. For women not taking HRT, there is an approximately eight percent lifetime risk of developing breast cancer. 1 "If the information provided to us by the Nurses' Health Study is now factored into this eight percent, approximately 11 percent of women who are estrogen users will ever develop breast cancer," said Dr. Robert Reid, Director of Reproductive Endocrinology and Infertility at Queen's University. "The greater risk is for older women (aged 60 to 64) who have taken hormones for greater than five years when the risk of breast cancer goes up to 13 percent," Dr. Jolly said. Putting the statistics further into perspective, the number of post-menopausal women who develop breast cancer is 2.5 per thousand in Canada. A 40 percent increase would then raise that number to four per thousand. "It is, therefore, very important to balance the benefits and risks of HRT, while considering hormone use and breast cancer risk," said Dr. Jolly. "It is imperative that each patient be assessed to determine if she is an appropriate candidate for HRT. For example, a woman at risk for cardiovascular disease (positive family history, smoker, diabetic, high cholesterol levels, elevated blood pressure) or a woman at risk for osteoporosis (family history of fractures, smoker, early menopause, petite body build, long-term cortisone user) should consider the very positive benefits that HR T offers," said Dr. Jolly. "Quality of life issues, such as hot flushes, vaginal dryness, painful intercourse, bladder difficulties, disturbances in mood and depression can also be significantly
JOURNAL SOGC
alleviated by timely and appropriate HRT. However, if a woman has none of the risk factors and has none or a few very tolerable symptoms, the use of HRT may not provide the added long-term health benefits," said Dr. Jolly. The SOGC strongly endorses the position that every woman in Canada should make an informed choice in establishing a midlife plan to promote health, to prevent disease, and to improve quality of life. 2 This should be accomplished using an individualized approach with continuing dialogue and careful monitoring of her risk/benefit ratio if she chooses HRT. The Society of Obstetricians and Gynaecologists of Canada will be issuing a bulletin regarding the Nurses' Health Study to all physicians in an upcoming issue of the Journal SOGC. REFERENCES
1.
2.
956
Bryant HE, Brasher PMA. Risks and Probabilities of Breast Cancer: Short-term Versus Lifetime Probabilities. Can Med Assoc Journal 1994;150(2):211-16. SOGC Menopause Consensus, J SOGC, May, 1994.
OCTOBER 1995
L E T T E R S
TO
T H E
To THE EDITOR:
' ' '
The Nurses' Health Study on HRT and breast cancer, published in the New England Journal of Medicine on June 15, 1995, reported an increased incidence of breast cancer in current users of estrogen replacement therapy, with or without progestin. A Seattle study comparing women with and without breast cancer, which showed completely different results, was published in the Journal of the American Medical Association (JAMA). The study failed to find any increased risk of breast cancer associated with either current or long-term use of estrogen-progestin HRT. Although the Seattle study is reassuring, it is one of the many (now over 40) population-based case-control studies, and is therefore, a retrospective review of the issues. This report included the histories of 1,029 Washington State women. Five hundred and thirty-seven women who had breast cancer between] anuary 1989 and June 1990 were randomly selected from the SeattlePuget Sound Cancer Registry. Another 492 women without a breast cancer history were randomly selected as controls. Both estrogen alone and combined with progestin use were examined in this report and did not appear to be associated with an increased risk of breast cancer in older women. The Nurses' Health Study, also an observational, casecontrol study, included almost 70,000 women between 1976 and 1992, and reported on 1,935 breast cancer cases diagnosed and 359 breast cancer deaths. This work suggests that there is an increased relative risk among longterm and current users of estrogen (a 32 percent increase for estrogen use alone and a 41 percent increase for combination therapy of estrogen and progestin). This study, which involved a large patient population and highly regarded investigators, must be given credibility. "Because of the protective effects HRT has against cardiovascular disease (the leading cause of death for Canadian women) and because of the strong protective effect against osteoporosis, we believe it is important that physicians and patients not draw premature conclusions from these studies," said Dr. Jolly. Hormone Replacement Therapy has been shown to reduce the risk of heart disease by 50 percent and to reduce the incidence of osteoporosis by 50 percent.
The appearance of two recent reports which examined the relationship between Hormone Replacement Therapy and breast cancer has given rise to a great deal of public concern. To address these concerns, the SOGC has evaluated these reports and has adopted a position which was communicated to the public. Because of the urgency of the issue, and to alleviate controversy and reassure Canadian women, a press release was issued on July 18, 1995. I would request that as a service to our members and readership an edited version of the release, which outlines the position of the SOGC, be published in the letters to the editor column. Yours sincerely, A.B. Lalonde, MD, FRCSC Executive Vice-President SOCIETY OF OBSTETRICIANS AND GYNAECOLOGISTS OF CANADA RESPONDS TO RECENT STUDIES ON HoRMONE REPLACEMENT THERAPY
Two recently published medical studies on the use of hormone replacement therapy (HRT) and breast cancer have generated significant public attention. In light of these studies, which had contradictory results, the Society of Obstetricians and Gynaecologists of Canada (SOGC) has met to discuss these findings and to reaffirm its position that women should assess their individual risk versus the benefits of HRT. "The release of these two studies in such a short time frame really highlights how important it is for the public to take such studies in stride and not to be reactive. Each new study provides that much more depth of understanding to physicians when discussing the appropriateness of HRT with their patients," said Dr. Elaine Jolly, Director of Menopause Clinic at the Ottawa General Hospital and Chair of the SOGC's Special Interest Group on Menopause and Aging. The Society's Special Interest Group believes strongly that the findings of the Nurses' Health Study and the new Seattle study need to be put into context for women who are taking or are considering taking HRT and for physicians treating menopausal patients.
JOURNAL SOGC
EDITOR
955
OCTOBER 1995
' ' ' Annually in Canada, there are some 40,000 deaths from myocardial infarction and some 100,000 osteoporotic fractures (approximately 20,000 of these are hip fractures). Twelve to 20 percent of women who sustain hip fractures will die within six months. There are approximately 3,900 deaths from breast cancer per year. The mortality from heart attack and osteoporotic fractures is, therefore, 10 times greater than that for breast cancer. The SOGC, however, does recognize the very real concern of women and their fear of developing breast cancer. The importance of careful monitoring, breast self-examination, routine mammograms, and physician assessments cannot be overemphasized. But there has been some misunderstanding of the statistics by physicians and patients as to what the percent increases really mean. For women not taking HRT, there is an approximately eight percent lifetime risk of developing breast cancer. 1 "If the information provided to us by the Nurses' Health Study is now factored into this eight percent, approximately 11 percent of women who are estrogen users will ever develop breast cancer," said Dr. Robert Reid, Director of Reproductive Endocrinology and Infertility at Queen's University. "The greater risk is for older women (aged 60 to 64) who have taken hormones for greater than five years when the risk of breast cancer goes up to 13 percent," Dr. Jolly said. Putting the statistics further into perspective, the number of post-menopausal women who develop breast cancer is 2.5 per thousand in Canada. A 40 percent increase would then raise that number to four per thousand. "It is, therefore, very important to balance the benefits and risks of HRT, while considering hormone use and breast cancer risk," said Dr. Jolly. "It is imperative that each patient be assessed to determine if she is an appropriate candidate for HRT. For example, a woman at risk for cardiovascular disease (positive family history, smoker, diabetic, high cholesterol levels, elevated blood pressure) or a woman at risk for osteoporosis (family history of fractures, smoker, early menopause, petite body build, long-term cortisone user) should consider the very positive benefits that HR T offers," said Dr. Jolly. "Quality of life issues, such as hot flushes, vaginal dryness, painful intercourse, bladder difficulties, disturbances in mood and depression can also be significantly
JOURNAL SOGC
alleviated by timely and appropriate HRT. However, if a woman has none of the risk factors and has none or a few very tolerable symptoms, the use of HRT may not provide the added long-term health benefits," said Dr. Jolly. The SOGC strongly endorses the position that every woman in Canada should make an informed choice in establishing a midlife plan to promote health, to prevent disease, and to improve quality of life. 2 This should be accomplished using an individualized approach with continuing dialogue and careful monitoring of her risk/benefit ratio if she chooses HRT. The Society of Obstetricians and Gynaecologists of Canada will be issuing a bulletin regarding the Nurses' Health Study to all physicians in an upcoming issue of the Journal SOGC. REFERENCES
1.
2.
956
Bryant HE, Brasher PMA. Risks and Probabilities of Breast Cancer: Short-term Versus Lifetime Probabilities. Can Med Assoc Journal 1994;150(2):211-16. SOGC Menopause Consensus, J SOGC, May, 1994.
OCTOBER 1995