Estrogen Therapy Linked to Improved Heart Health in Menopausal Women

The decision to initiate hormone therapy during menopause, which marks the end of a woman's reproductive years, remains a contentious subject among healthcare providers and patients alike. While hormone therapy is commonly prescribed to alleviate distressing symptoms such as hot flashes and night sweats, there is ongoing uncertainty regarding its long-term implications for cardiovascular health.

Recent research led by a team from Pennsylvania State University provides new insights into the potential heart health benefits of estrogen-based hormone therapies. An analysis of data derived from the Women's Health Initiative (WHI)--a long-term study focused on menopausal women--indicates that estrogen therapy may positively impact cardiovascular health markers over time.

Specifically, the study suggests that hormone therapy can lower levels of lipoprotein(a), a genetic marker associated with increased risks of heart attack and stroke. The findings, published in the journal Obstetrics & Gynecology, contribute to the ongoing evaluation of the relationship between hormone replacement therapy and cardiovascular health, offering valuable guidance for patients and healthcare professionals.

According to the researchers, there has been a shift in understanding the safety of hormone therapy for younger menopausal women--those within ten years post-menopause--who are generally healthy and have no prior cardiovascular issues. The decline in estrogen during menopause is linked to higher risks of cardiovascular disease due to its effects on cholesterol levels, blood pressure, and arterial plaque buildup.

The research team focused on the long-term effects of hormone therapy on cardiovascular biomarkers, an area that has not been extensively studied in the past. They examined data from a subgroup of participants in an oral hormone therapy clinical trial associated with the WHI, spanning a period of six years. Participants were divided into two groups: one receiving estrogen alone and the other receiving a combination of estrogen and progesterone.

Over the study duration, findings revealed that both hormone therapy groups experienced beneficial changes in key cardiovascular biomarkers. Specifically, levels of low-density lipoprotein (LDL) cholesterol, often referred to as "bad" cholesterol, decreased by approximately 11%, while total cholesterol and insulin resistance also showed reductions. Conversely, levels of high-density lipoprotein (HDL) cholesterol, known as "good" cholesterol, increased by 13% in the estrogen-only group and by 7% in the combination group.

Interestingly, the study noted a significant reduction in lipoprotein(a) levels--15% in the estrogen-only group and 20% in the estrogen-plus-progesterone group. This finding is particularly noteworthy as lipoprotein(a) levels are primarily influenced by genetics rather than lifestyle factors, making this reduction a significant discovery in the field of cardiovascular health.

When assessing the findings based on self-reported racial and ethnic backgrounds, participants with American Indian or Alaska Native ancestry exhibited a more pronounced decrease in lipoprotein(a) levels, as did those of Asian or Pacific Islander descent. The reasons for these disparities remain unclear, prompting further investigation in future studies.

The form of estrogen utilized in this research was conjugated equine estrogens, a commonly prescribed oral estrogen therapy. It is important to note that oral hormone therapy undergoes metabolism in the liver, which may elevate inflammatory markers, potentially explaining increases in triglycerides and coagulation factors observed in the study.

For individuals considering hormone therapy during menopause, a comprehensive cardiovascular risk assessment is advisable, regardless of their history with heart disease. This approach will provide healthcare providers with essential information to tailor treatments effectively.

While hormone therapy is not currently approved by the FDA to mitigate risks associated with coronary artery disease or stroke, the findings from this study may influence future guidelines and clinical practices.