The Potential of HRT to Treat Pulmonary Hypertension

New research suggests that hormone replacement therapy (HRT) may improve symptoms of pulmonary hypertension in women. This condition, caused by high blood pressure in the vessels that supply the lungs, affects about 1% of the global population and is more common in females. Scientists believe estrogen may play a critical role in this gender disparity.

Estrogen’s Role in Pulmonary Hypertension

Pulmonary hypertension is a progressive disease with no current cure, significantly impacting quality of life. Past studies indicate that females are more frequently affected by this condition, and it is hypothesized that estrogen could be a contributing factor.

Study Overview

Researchers from The University of Arizona College of Medicine Tucson explored this connection. They presented their findings at the American Thoracic Society 2024 International Conference, though the results are not yet published in a peer-reviewed journal.

The study involved 742 female participants classified into five groups based on the World Symposium on Pulmonary Hypertension's categories:

• Group 1: Pulmonary arterial hypertension

• Group 2: Pulmonary hypertension caused by left heart disease

• Group 3: Pulmonary hypertension caused by lung disease

• Group 4: Pulmonary hypertension from chronic blood clots in the lungs

• Group 5: Pulmonary hypertension from unknown causes

Additionally, participants included women with risk factors for pulmonary hypertension and healthy controls.

Findings on Hormonal Impact

The researchers examined the impact of both endogenous (natural) and exogenous (HRT) hormone exposure. Endogenous exposure was measured by lifetime duration of menstruation, while exogenous exposure was defined as any use of HRT.

Dr. Audriana Hurbon and her team found that average pulmonary arterial pressure decreased with a greater lifetime duration of menstruation across all pulmonary hypertension groups. They also assessed right ventricular function and found no significant difference with lifetime duration of menses regarding pulmonary vascular disease. However, they observed an improvement in right ventricular ejection fraction.

HRT Benefits

The study found that HRT was associated with lower mean pulmonary artery pressure, higher right ventricular fractional shortening, and right ventricular ejection fraction. These improvements were particularly notable in Group 1 pulmonary hypertension.

“So far, our preliminary data has been positive with improvement in mean pulmonary arterial pressure, pulmonary vascular resistance, right ventricular ejection fraction, and right ventricular fractional shortening with the use of HRT,” Dr. Hurbon said.

Expert Opinions and Controversies

Dr. Nicole Weinberg, a cardiologist at Providence Saint John’s Health Center, acknowledged the potential benefits but also highlighted the risks. HRT is known to be vasodilating, which can improve blood flow but also increase clotting risks.

Dr. Cheng-Han Chen, an interventional cardiologist, emphasized that while the study offers promising new avenues for research, it is still too early to change clinical practices based on these findings alone. Future research, particularly randomized control trials, is necessary to confirm the relationship between estrogen and improved pulmonary hypertension outcomes.

Conclusion

The preliminary data suggests that HRT may help improve symptoms of pulmonary hypertension in women, especially those in Group 1. However, further research is needed to fully understand the benefits and risks, and to develop evidence-based guidelines for HRT use in pulmonary hypertension treatment.