Menstruation and asthma link
Wednesday, 21 March 2001
A new Australian study has confirmed asthma gets worse in the days leading up to and during menstruation.
Researchers at Brisbane's Mater Misericordiae Hospital and Princess Alexandra Hospital found nearly half the women studied suffered worse asthma symptoms around the time of their period than other times of the month.
The worsening of asthma was related to diminishing levels of the sex hormone progesterone prior to menstruation, Dr Glen Rice-McDonald told ABC Science Online.
Dr Rice-McDonald, from the Mater research team, said his study was 'prospective' in that it measured progesterone levels as well as asthma symptoms throughout the menstrual cycles of 51 women.
Forty-seven per cent experienced worse asthma symptoms either the week before, or during, their period. Women whose asthma symptoms deteriorated also experienced a significantly longer period of menstruation and higher levels of premenstrual tension.
To confirm that progesterone was the cause of the asthma worsening, Dr Rice-McDonald also measured the concentration of molecules which cause inflammation in airways. He found they rose as progesterone levels dropped and asthma symptoms worsened.
"Other studies have shown that there is a biologically plausible mechanism for a drop in progesterone leading to inflammation," he said.
Dr Rice-McDonald said this was the first Australian study to demonstrate a link between progesterone and the worsening of asthma symptoms. He also said it was the most accurate because previous research had been 'retrospective', asking women to recall whether their asthma symptoms were worse around the time of their period.
"We tested this recall [method] and found it was highly inaccurate," said Dr Rice-McDonald.
"A lot of people said 'yes', their symptoms were worse when, in fact, we didn't find a link. Others said 'no', and we found there was a link," he said. "We suspect there is a confusion between the symptoms of premenstrual tension and asthma in some women.
"The idea that there is a link between female sex hormones and fluctuations in asthma has been around since 1931 however it hasn't permeated the medical literature or standard practice," Dr Rice-McDonald said.
"When seeing female patients with asthma, most doctors don't consider the link between asthma symptoms and the menstrual cycle," Dr Rice-McDonald said.
In a related address, Sydney consultant respiratory physician Dr Deborah Yates said a woman's hormones could also affect the severity of other medical conditions including epilepsy and migraine.
This research was presented yesterday at the Annual Scientific Meeting of the Thoracic Society of Australia & New Zealand in Brisbane.