#253 ‒ Hormone replacement therapy and the Women’s Health Initiative: re-examining the results, the link to breast cancer, and weighing the risk vs reward of HRT | JoAnn Manson, M.D. | The Peter Attia Drive

Intro

In this episode of “The Peter Attia Drive” podcast, Dr. Peter Attia interviews Dr. JoAnn Manson, a renowned professor of medicine and chief of the division of prevention medicine at Brigham and Women’s Hospital. Dr. Manson is a highly cited researcher with a focus on randomized clinical prevention trials and the role of hormones in chronic disease in women. The episode delves into the Women’s Health Initiative study, which examined hormone replacement therapy (HRT) and its implications for women’s health. Dr. Manson provides insights into the nuances of the study, dispels fears surrounding HRT, and discusses the risk vs reward of hormone therapy.

Main Takeaways

Examining the Women’s Health Initiative Study

• The Women’s Health Initiative study aimed to test the advisability of hormone replacement therapy for preventing chronic diseases.
• The study had 40 principal investigators throughout the country.
• Observational studies in the 1980s and 1990s showed promising results for lower risk of heart disease, cognitive decline, and all-cause mortality with hormone therapy formulations.
• The study examined the use of hormone therapy formulations, including conjugated estrogen with or without medroxyprogesterone acetate, and their effects on women’s health.

Interpreting the Results of the Women’s Health Initiative Study

• The study was prematurely stopped due to the headline that “estrogen causes breast cancer,” leading to a reduction in the use of hormone therapy for prevention of chronic diseases.
• The increased risk of breast cancer with hormone therapy is mostly attributable to the progestin medroxyprogesterone acetate (MPA).
• Estrogen alone does not increase the risk of breast cancer, but hormone therapy is associated with increased risk of estrogen receptor-positive breast cancers.
• Observational studies on hormone therapy and breast cancer risk may have been confounded by differences in mammographic screening patterns.

Weighing the Risk vs Reward of Hormone Therapy

• The risk-benefit ratio of hormone therapy depends on the individual patient’s age, health status, and symptoms.
• Hormone therapy should not be denied to women with bothersome hot flashes and night sweats to improve their quality of life, especially healthy women in early menopause.
• The adverse events associated with hormone therapy are relatively rare, with one extra case of breast cancer, heart attack, or blood clot per 1,000 women per year.
• Timing is crucial when it comes to hormone therapy, and the absolute risks of these hormones are much lower in early menopause than in later menopause.

Summary

Examining the Women’s Health Initiative Study

The Women’s Health Initiative study, in which Dr. JoAnn Manson was a principal investigator, aimed to determine the advisability of hormone replacement therapy for preventing chronic diseases in women. Observational studies in the 1980s and 1990s showed promising results for lower risk of heart disease, cognitive decline, and all-cause mortality with hormone therapy formulations. The study examined the use of hormone therapy formulations, including conjugated estrogen with or without medroxyprogesterone acetate. The goal was to determine the effects of these formulations on women’s health and provide evidence-based recommendations.

Interpreting the Results of the Women’s Health Initiative Study

The Women’s Health Initiative study was prematurely stopped due to concerns about the increased risk of breast cancer associated with hormone therapy. However, further analysis reveals that the increased risk is mostly attributable to the progestin medroxyprogesterone acetate (MPA), while estrogen alone does not increase the risk of breast cancer. Observational studies on hormone therapy and breast cancer risk may have been confounded by differences in mammographic screening patterns. It is important to consider these nuances when interpreting the results of the study and making decisions about hormone therapy.

Weighing the Risk vs Reward of Hormone Therapy

The risk-benefit ratio of hormone therapy depends on various factors, including the individual patient’s age, health status, and symptoms. Hormone therapy should not be denied to women with bothersome hot flashes and night sweats, as it can significantly improve their quality of life. The adverse events associated with hormone therapy are relatively rare, with a minimal increase in the risk of breast cancer, heart attack, or blood clot. Timing is crucial when considering hormone therapy, as the absolute risks are much lower in early menopause compared to later menopause. It is essential for women to discuss their options with a knowledgeable clinician and weigh the pros and cons based on their specific circumstances.

Conclusion

Dr. JoAnn Manson’s insights into the Women’s Health Initiative study shed light on the complexities of hormone replacement therapy and its implications for women’s health. The study’s premature halt and subsequent misinterpretation led to a reduction in the use of hormone therapy, potentially denying relief to women experiencing bothersome symptoms. It is crucial for women to have informed discussions with their healthcare providers to weigh the risks and benefits of hormone therapy based on their individual circumstances. The podcast episode provides valuable information to dispel fears surrounding hormone replacement therapy and encourages shared decision-making for optimal patient care.