According to research, presented on July 28 at the 2015 American Association for Clinical Chemistry (AACC) Annual Meeting & Clinical Expo in Atlanta, US, hair samples can be used to measure the effects of asthma on the cortisol levels of women during pregnancy.
The research shows that cortisol tend to be lower among pregnant women with asthma than among pregnant women without the chronic, inflammatory lung disease – the findings that suggest that hair samples may provide scientists with a simple tool for determining if and how cortisol is linked to poorer pregnancy outcomes.
“We hope hair samples will help establish the role that changes in cortisol levels throughout pregnancy have on the health of women and their children,” said study co-author Laura Smy, a PhD student at the University of Toronto.
While currently researchers ask pregnant women for frequent blood or saliva samples to track their cortisol levels, these results are difficult to interpret as cortisol fluctuates during the day and current methodology reflects only one point in time. Hair, on the other hand, stores cortisol levels over a long period of time with one centimetre showing cortisol levels during a particular month.
To investigate whether hair samples could be used to assess the effects of asthma on cortisol levels during pregnancy, a research team led by Gideon Koren, MD, a clinical pharmacologist at the University of Toronto, and Bruce Carleton, PharmD, at the University of British Columbia, collected hair samples from 93 pregnant women, of whom 62 had asthma and 31 did not. About half of the women with asthma were being treated with inhaled corticosteroids.
“For both the control and the asthma groups we could see a rise in cortisol over the course of the pregnancy and then a decline during the post-partum period,” said Smy. “”For the individuals with asthma, whether or not they were using inhaled corticosteroids, their response to the cortisol increase was dampened. They had significantly lower hair-cortisol levels during both their second and third trimesters than the women in the control group.”
According to Smy, the dampened response to cortisol observed in the current study may be due to “adrenal fatigue”—prolonged exposure to high cortisol levels that eventually causes the adrenal glands to significantly reduce their output of the hormone. Future research will be needed, she added, to both confirm this study’s findings and to determine the role that changes in cortisol during pregnancy may have on pregnancy outcomes and fetal wellbeing.
