Hormone replacement therapy (HRT) can be very useful in helping women deal with the symptoms of menopause. However, hormones are powerful biochemical messengers so it’s perhaps no surprise that HRT has been associated with various health risks. A new study from researchers in Mexico and France now identifies a link between HRT use and asthma. The report comes from the French E3N study which includes around 100,000 women born between 1925 and 1950 and is part of the European Prospective Investigation into Cancer and Nutrition. Nearly 58,000 women from the group were asked about HRT use and development of asthma symptoms every two years from 1990 and 2002. None of them had asthma at the start of the menopause.

Around 36% of the women had never been on HRT, previous users accounted for 4.5% and just under 56% were recent HRT users. There were 569 new cases of asthma occurring during the monitoring period. Compared to women who had never been on HRT, those who did use it were 21% more likely to develop asthma. When the findings were analyzed further, it emerged that it is the risk of asthma was significant only among women using estrogen-only HRT. These women had a 54% higher chance of developing asthma than women who had never used HRT. And estrogen-only HRT users who had never smoked or had some form of allergy prior to their asthma diagnosis had an even higher risk of asthma – 80% and 86% higher, respectively. Previous research has shown that female hormones play a role in asthma – it is more common among girls once they start their periods and hospital admission for asthma is more common among women than it is among men. And the severity of asthma varies throughout the menstrual cycle and during pregnancy. Its incidence falls after menopause, except among women who put on a lot of weight. This new health risk needs to be taken into account when a woman is considering HRT for menopausal symptoms.

Source:

Romieu I et al Postmenopausal hormone therapy and asthma in the E3N cohort Thorax Online First 8^th February 2010 doi10.1136/thx.2009.116079