Bulletin Index/

Reduce Differences in Health Status

1.What Makes Us Healthy, What Makes Us Sick?

2. The Midlife Health Needs of Women with Disabilities

3. The Effects of Social Isolation and Lonliness on the Health of Older Women

4. Immigration and Perinatal Risk

Build Healthy Public Policy

5. Public Health vs Chemoprevention

6. Restructuring and Women's Health: The Fisheries Crisis in Newfoundland

Strengthen Community and Personal Action

7. Out in the Cold: Lesbian Health in Northern BC

8. Empowerment in the Context of Poverty: Low-income Mothers in Saskatoon

9. Affirming Immigrant Women's Health Practices in PEI

Public Health vs Chemoprevention

While medicine has done much to ease human suffering, public health has done more to prevent it. The health gains from public health measures such as better nutrition, clean drinking water and safer workplaces far outstrip the gains from medicine.¹

Public health policy accepts small risks, such as those incurred by vaccination or seat belts in cars, for large benefits. "Chemoprevention" experiments, which test potent drugs to prevent disease, introduce a troubling new standard: large risks are justified by small or ambiguous benefits. Canadian women are involved in these experiments, which blur the boundary between disease prevention, where safety is paramount, and disease treatment, where risks to the sick are weighed against potential improvements in their condition. The strategy of prescribing drugs to healthy people now threatens to overtake, and even displace, the traditional public health strategy of identifying and removing or reducing the causes of disease. At the same time, Canadian safety standards for medications, medical devices and environmental contaminants are quietly eroding.

Breast Cancer and Chemoprevention
Over the past decade, breast cancer has dominated the chemoprevention debate. In April 1998, front-page headlines described a breakthrough in preventing breast cancer: "We know for the first time in history that we can prevent cancer through pharmaceuticals," said one of the researchers in the Breast Cancer Prevention Trial (BCPT), an experiment involving 13,388 Canadian and American women.² Six months later, the U.S. Food and Drug Administration approved the use of tamoxifen—previously approved only to treat breast cancer—for women "at high risk" of developing the disease.³ Health Canada has not approved tamoxifen (an estrogen antagonist) for breast cancer risk reduction, which means pharmaceutical companies cannot promote the drug for that purpose in Canada. However, Canadian physicians can prescribe the drug to healthy women at their own discretion, a practice known as "off-label" use.

In the BCPT, tamoxifen lowered the risk of breast cancer but raised the risks of endometrial cancer, blood clots and vision problems, prompting one physician to observe that "disease prevention" had been replaced by "disease substitution." 4 Three women in the tamoxifen arm of the trial died from blood clots in their lungs.

Healthy Canadian and American women are now being recruited to the Study of Tamoxifen Against Raloxifene (STAR), a follow-up to the BCPT that compares tamoxifen to a similar drug, raloxifene. Raloxifene also causes blood clotting. (All women in the STAR trial will be exposed to one drug or the other.) Women’s health groups have critiqued the breast cancer chemoprevention trials as the latest in a series of risky drugs and medical products marketed for use in women without adequate scientific rationale or testing. Nor is breast cancer the only disease for which treatment drugs are being tested for prevention. Others include heart disease, thinning bones, prostate cancer and schizophrenia.

The Precautionary Principle vs. Risk Management
Women’s health groups, public health researchers, ethicists, environmentalists and many health practitioners have stressed the need to adopt a public health approach to breast cancer prevention. They promote the Precautionary Principle, a safety-first premise that states that when there are reasonable scientific grounds for believing a process or product may not be safe, even when cause and effect relationships are not fully understood, preventive action must be taken. If Health Canada made the Precautionary Principle its standard for health protection in regulating food, drugs and medical devices, and in protecting the environment, the prevention of disease would be maximized without recourse to drugs. This would also protect the public from the testing and marketing of chemoprevention drugs that introduce new threats to health. However, in the revised Canadian Environmental Protection Act (1999), the government diluted the initially strong statement of the Precautionary Principle after industry interventions led to last-minute amendments.5 Further, the government’s discussion paper on health protection, Health Protection for the 21st Century: Renewing the Federal Health Protection Legislation (1998), embraced an antithetical approach through a "modern risk management framework." 6

The Reagan administration introduced risk management to American health and environment agencies in 1983, writes science historian Robert Proctor in his book, Cancer Wars. Risk management defines risk as an unavoidable fact of life. No longer is pollution viewed as a problem to be remedied; rather, toxins in the environment are negotiable evils. Risk assessors (scientists) determine the magnitude of a given risk, while risk managers (policy makers) determine whether that risk is acceptable. "The net effect was almost invariably to stymie health and environmental regulations," says Proctor. 7

Thus, financial risks and benefits are factored into the same equation as health risks and benefits. Risk management invokes the ALARA Principle: human exposures to risks are kept As Low As Reasonably Achievable, "social and economic factors being taken into account." 8 A risk management framework will favour chemoprevention over public health strategies for disease prevention, precisely because most drugs for the worried well have significantly larger potential markets than drugs for the sick. This tactic also shifts the cost from society, through government-funded prevention measures, to the individual who will pay for the drug.

Health Canada assembled a working group to examine how the ALARA Principle was applied to radiation and chemical exposures. Members found that levels of acceptable risk associated with established guidelines varied "up to a million-fold." 9 They concluded nonetheless that risk management strategies to regulate both radiation and chemicals "provide a high degree of health protection based on the absence of observable health effects using epidemiological methodology" [italics added]. 10 Thus, measurable levels of radiation, genotoxic chemicals and endocrine-disrupting substances are assumed to be safe because epidemiological studies do not yet show observable health effects. This reasoning commits what Peter Saunders of the Institute of Science in Society calls "the mathematical fallacy that absence of evidence is the same as evidence of absence." 11 In the short term, reducing and eliminating the causes of disease would lower industry profits by requiring clean-up of toxic substances, changes to polluting technologies and workplace measures to prevent accidents or exposure to agents that cause disease. In the long term, however, such steps promote sustainable development and may save industry money. They have finite costs, provide long-term health benefits to entire populations, and usually alleviate a range of illnesses rather than just one.

Combatting the Drift to Chemoprevention
For a decade the chemoprevention debate has incited FDA hearings in the United States, media coverage and meetings of community groups. Although hundreds of Canadian women have been recruited to the BCPT and STAR trials, Canada’s health protection agency has yet to provide a policy forum to which women could bring their concerns. The renewal of Canada’s health protection system, now under way, must address the public health implications of chemoprevention. Policy changes are needed at the highest level to affirm the Precautionary Principle as the basis for health protection and to confine chemoprevention to situations where it can be used ethically, safely and economically. To achieve this goal, the Working Group on Women and Health Protection recommends that:

• The regulation of drugs, food, radiation equipment and the Canadian environment should all occur through a system that is independent from industry.
  
  
• The Canadian government provide venues for public input at all stages of chemoprevention drug testing and approvals, and post transcripts of these meetings on the internet to ensure public access to the information.
  
  
• A regulatory office be created to oversee clinical trials in Canada, including chemoprevention trials, in consultation with relevant professionals and public interest health groups.
  
  
• Health Canada be mandated to intervene at regulatory hearings in the United States and other countries carrying out clinical trials that involve Canadian participants to demand that the safety of Canadian participants be protected.

The Working Group on Women and Health Protection is financially supported by the Centres of Excellence for Women’s Health. To obtain a copy of the paper, "Preventing Disease: Public health versus chemoprevention," see the Working Group on Women and Health Protection website at www.web.net/~desact. The views expressed in this article do not necessarily represent the official policy of Health Canada.

Working Group on Women and Health Protection
DES Action Canada
5890 Monkland Ave, Suite 203, Montreal, QC H4A 1G2
Web site: www.web.net/~desact

Atlantic Centre of Excellence for Women’s Health
P.O. Box 3070, Halifax, NS  Canada B3J 3G9
Tel: (902) 470-6725 Toll Free: 1-888-658-1112 Fax: (902) 470-6752 Website: www.medicine.dal.ca/acewh E-mail: acewh@dal.ca

NOTES
¹Centers for Disease Control. Ten great public health achievements–United States, 1900-1999. Morbidity and Mortality Weekly Report, April 2 1999;48(12):241.

² Dr. Richard Margolese quoted by Semenal S. Breast cancer treatment hailed. The Gazette 1998 April 6;A1.

³Letter to Zeneca Pharmaceuticals from Robert Temple, M.D., Director, Office of Drug Evaluation, Center for Drug Evaluation and Research, FDA. Web reference: www.fda.gov/cder/foi/appletter/1998/17970s40.pdf

4 Fugh Berman A, Tamoxifen in healthy women: Preventive health or preventing health? National Women’s Health Network News 1991; September/October:3.

5 VanderZwaag D. The precautionary principle in environmental law and policy: Elusive rhetoric and first embraces. Journal of Environmental Law and Practice 1999; 8:355-375.

6 Health Canada. Health protection for the 21st century: Renewing the federal health protection legislation. Ottawa: Health Canada, July 1998. Web reference: www.hc-sc.gc.ca/hpb/transitn/index.html; 6.

7 Proctor RN. Cancer Wars: How Politics Shapes What We Know and Don’t Know About Cancer. Basic Books, 1995;84.

8 Health Canada, Atomic Energy Control Board, Ontario Ministry of Environment and Energy Joint Working Group. Assessment and management of cancer risks from radiological and chemical hazards. Ottawa: Health Canada, 1998. Web reference: www.hcsc.gc.ca/ehp/ehd/catalogue/general/98ehd216.pdf: 9.

9 Health Canada et al., 1998;9.

10 Health Canada et al., 1998;42.

11 Saunders PT. Use and abuse of the Precautionary Principle. Institute of Science in Society (ISIS) submission to the U.S. Advisory Committee on International Economic Policy. London, July 13 2000.

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