Female hormones could play a role in lung function decline during aging.
Many women experiencing menopause choose to undergo hormone replacement therapy (HRT) to relieve the symptoms, such as hot flashes and fatigue. Findings presented at the European Respiratory Society International Congress suggest that HRT may benefit lung function in these patients as well.
Included in the study were 3713 women who were followed up with for 20 years. The authors found that patients who took HRT for at least 2 years had better lung function compared with women who never started the treatment.
"Lung function peaks during the mid-twenties, and from then on it will go down; however, it is possible to identify which factors influence the decline, either by slowing it down or accelerating it,” said researcher Kai Triebner, PhD. “One accelerating factor, for example, is the menopause. Therefore, a key question is whether HRT could.”
Lung function was evaluated at baseline and then after 20 years through forced vital capacity tests, which measure the amount of air exhaled after taking a deep breath.
Patients who took HRT for at least 2 years lost 46 ml less of lung volume during the study compared with women who abstained from treatment, according to the study.
"This will most likely not be clinically significant for healthy women. However, in women who are suffering from airway diseases, the decline in lung function may influence quality of life, as it could lead to an increase in shortness of breath, reduced work capacity and fatigue," Dr Triebner said. "To put these findings in context, if a woman smoked a pack of cigarettes a day for 3 years, the loss of forced vital capacity would correspond roughly in size to 46 ml.”
The authors hypothesize that female hormones, including estrogen, may be important for lung function.
"Our findings show that female sex hormones are important for the preservation of lung function in middle-aged women,” Dr Triebner said.
The authors adjusted for potentially confounding factors, such as type of spirometer, length of follow-up, and enrollment center. They report that physical activity and surgically-onset menopause were not found to impact lung function decline, according to the study.
"However, physical activity has a number of beneficial effects, so in my personal opinion a balanced amount of physical exercise is desirable," Dr Triebner advised.
The authors caution that the study results should not be used as a case for or against the use of HRT for women with menopause. Although HRT can relieve menopause symptoms and reduce the risk of osteoporosis, it was also found to increase the risk of breast cancer and heart and blood vessel problems risks, according to the study.
The authors advise that patients should understand the risks and benefits of HRT to determine whether the treatment is appropriate.
"Women, as well as physicians, need to be better informed about health changes during the postmenopausal period. This study provides more information, which represents another building block and, together with other existing studies, it can pave the way to the right decision for each individual woman," Dr Triebner concluded. “Women with existing health problems, for instance asthma, need to be followed more thoroughly through the menopausal transition and be provided with advice on medications that take the changing hormone levels better into account — ideally with a personalised [sic] approach.”