Long distance phone calls allow researchers to uncover risks and treatments for mothers with asthma

Aug 29 2014

By Dr Vanessa Murphy

The highlight of my scientific career to date has been working on an exciting collaboration with the world leader in the field of asthma in pregnancy, Prof Michael Schatz and colleagues in San Diego, USA.
When I was a young PhD student in 2000, I read a lot of journal articles on everything related to my research on asthma during pregnancy, and the authors became well-known names to me. Michael Schatz, in particular, was a prolific publisher of both original research articles and review articles on the topic, publishing many clinical studies of pregnant women with asthma, which greatly interested me.

It seemed a little daunting that his first publication on “Corticosteroid therapy for the pregnant asthmatic patient” had been published in 1975, 2 years before I was even born!

So, in 2005, when I went to my first American Thoracic Society (ATS) Conference, and realised that he was presenting in a poster session, I found his poster, and bravely introduced myself. What I discovered was a gentleman in every sense of the word, who even knew who I was (presumably from peer reviewing my own publications in the previous few years), and was genuinely pleased to have met me, and was keen to hear all about my research plans. Following the conference he wrote to me to let me know that he’d had a chance to read my review article which had recently been published in the European Respiratory Journal.

In 2007, I returned to the ATS, and this time Michael came to see my poster, and he had a proposal to make – that we work together on a systematic review and meta-analysis of adverse perinatal outcomes in pregnant women with asthma. While there was a wealth of literature on this subject, much of it was conflicting, with some studies finding that pregnant women with asthma were at increased risk of adverse outcomes such as preterm birth, low birth weight, pre-eclampsia and congenital malformations, while others found no increased risk of poor outcomes compared to pregnant women without asthma. The review and meta-analyses we performed were an important way to summarise the existing literature and determine the extent of the risks to pregnant women with asthma.
The collaboration itself was conducted entirely via telephone meetings and emails, and initially involved 6 of us – Michael, Jennifer Namazy and Tina Chambers in San Diego, and me, Peter Gibson and Heather Powell in Newcastle. We always enjoyed our friendly phone “meet-ups” and to date I have not met the other two American collaborators. The majority of the work was conducted between late 2007 and 2009, when I went on maternity leave, having just completed the write up of our review and all the meta-analyses. Heather and I conducted the literature search, and along with Jennifer we assessed all the articles for the inclusion criteria and undertook the data extraction process, checking each other’s work. We used a computer program called Revman to perform the meta-analyses and Michael, Tina and Peter provided valuable input into the interpretation of the data we produced.

Our first publication appeared in the British Journal of Obstetrics and Gynaecology in 2011 (Murphy, Namazy, Powell, Schatz, Chambers, Attia, Gibson, 2011; 118(11): 1314-23), and was the first systematic review and meta-analysis examining the risk of adverse perinatal outcomes in pregnant women with asthma. This publication successfully combined previous research with differing study design, numbers and populations into meta-analyses, which indicated that maternal asthma was associated with significantly increased risks of preterm labour and delivery, pre-eclampsia, low birth weight and small for gestational age. In addition, we presented the novel finding that active asthma management may mitigate some of the risk of maternal asthma, particularly on preterm labour and delivery.

Four additional publications resulted from our work. One was a letter to BJOG (Murphy, Namazy, Powell, Schatz, Chambers, Attia, Gibson, 2012; 119(4): 508-9) in response to correspondence to the journal related to our first publication. Jennifer Namazy also wrote up a publication which covered our analysis of the risk of adverse outcomes among pregnant women with severe asthma, asthma exacerbations in pregnancy and oral corticosteroid use (Namazy, Murphy, Powell, Gibson, Chambers, Schatz, European Respiratory Journal 2013; 41(5): 1082-90). This demonstrated that the risk of low birth weight was three times higher when women had asthma exacerbations during pregnancy, and that the risk of preterm birth was significantly higher when oral corticosteroids were used to treat exacerbations in pregnancy.

In 2012 we made the decision to update our systematic review, since several of our findings remained unpublished and would be more likely to be accepted if up to date. In this part of the project, we added Dr Wang Gang, a visiting fellow from China, to the team. He helped update our literature search and data extraction, and this added great value to our data, resulting in two further publications highlighting that maternal asthma is also associated with adverse maternal (pre-eclampsia, gestational diabetes and caesarean section), placental (placenta previa) and neonatal outcomes (congenital malformations, preterm birth, intrauterine growth restriction, neonatal hospitalisation and neonatal death).

One of these publications was also accepted by the British Journal of Obstetrics and Gynaecology (Murphy, Wang, Namazy, Powell, Gibson, Chambers, Schatz, 2013; 120(7):812-22), and the other was published in the Journal of Maternal Fetal and Neonatal Medicine (Wang, Murphy, Namazy, Powell, Schatz, Chambers, Attia, Gibson, 2014; 27(9): 934-42).

In addition to being an extremely productive collaboration, many of these findings formed the basis of our future original research examining novel management strategies for pregnant women with asthma and their impact on perinatal and infant outcomes.

In late 2013, Michael invited me to co-author a review article with him, which has now been published in European Respiratory Review. It was a great thrill for me, after admiring Michael’s work for so long, to see our review published:“Asthma in pregnancy: a hit for two” – Vanessa E Murphy and Michael Schatz (2014).

*** Dr Vanessa Murphy is a Postdoctoral Research Fellow in the School of Medicine and Public Health, The University of Newcastle