Hormone Replacement Therapy and Increased Asthma Risks

A 12 year study involving more than 58,000 women has concluded that both hormone replacement therapy (HRT) after menopause and estrogen only therapy may significantly increase a post-menopausal woman’s risk for asthma. The study compared one set of women who had never undergone HRT with a group that had received hormone replacement therapy. In comparison, the HRT group was found to be at a 21% greater risk for asthma. The risk more than doubles for the estrogen-only therapy group to 54%.
The study sought to learn more about the relationship between different types of hormone replacement therapies and their risk for contracting asthma after menopause.
“Epidemiological studies have suggested that female hormones might play a role in asthma and that menopausal hormone therapy (MHT or …HRT) might increase the risk of asthma in postmenopausal women,” write Isabelle Romieu, MD, of the Instituto Nacional de Salud Publica, Cuernavaca, Morelos, Mexico, and colleagues. “The mechanisms underlying the link between hormonal factors and asthma risk are still not clearly understood. Knowing whether MHT affects this risk and if so, whether different preparations have a similar effect would provide a useful insight into the mechanisms by which the hormonal milieu acts on the airways.”
Leanne Metcalf, director of research at the advocacy group Asthma UK, agreed with Romieu,””There is now a large body of evidence suggesting a link between female hormones, including the use of HRT, the development of asthma and its severity.”
Prior to the 2002 Women’s Health Initiative study, hormone replacement therapy had been a preferred method of treating severe hot flashes and vaginal dryness. However, after the WHI study found HRT to be linked to ovarian cancer, breast cancer, and strokes, the method experienced a sharp drop.