Optimising the management of asthma during pregnancy

Background: Uncontrolled asthma during pregnancy is associated with the maternal hazards of asthma exacerbation, and perinatal hazards including intrauterine growth restriction and preterm birth. Interventions directed at achieving better asthma control during pregnancy should be considered a high priority in order to optimise both maternal and perinatal outcomes. Poor adherence to asthma medication regimens during pregnancy and suboptimal prescribing in pregnant women have both been shown to jeopardise asthma control. These barriers need to be understood in order to inform the development of interventions for resolving these problems. The aim of this PhD was firstly to ascertain the safety of preventive asthma medications during pregnancy, then explore barriers to and facilitators of maternal asthma management and finally, to design and evaluate an informed intervention to optimise asthma management during pregnancy. Methods: A four phase project was conducted to contribute to optimising asthma management during pregnancy. Phase 1 was a systematic review of the safety of preventive asthma medications during pregnancy. Phase 2 involved investigating asthma management and prescribing trends during pregnancy through a postal survey of general practitioners (n=842) involved in shared maternity care at the three largest maternity hospitals in Victoria, Australia. Phase 3 explored the factors associated with adherence to asthma medications and experiences of pregnant asthmatic women through in-depth interviews (n=23). Finally, Phase 4 brought the results together in a randomised controlled trial testing a Multidisciplinary Approach to Management of Maternal Asthma (MAMMA©) in pregnant women with asthma (n=60). Both intervention and control (usual standard care) groups were followed prospectively and their asthma control was assessed at 3 and 6 months using the Asthma Control Questionnaire (ACQ) to evaluate the effectiveness of the intervention. Pregnant women with asthma were recruited from antenatal clinics and/or databases from two maternity hospitals in Victoria, Australia (Mercy Hospital for Women, and The Royal Women’s Hospital). Key findings: • Phase 1 (Chapter 2): current safety data have not been able to establish a direct association between asthma medication use during pregnancy and poor outcomes, whereas there is an abundance of literature supporting the risks of uncontrolled asthma. Women should not refrain from taking their asthma medications during pregnancy. • Phase 2 (Chapter 4) : Over a quarter of general practitioner respondents may be advising patients to reduce or discontinue their asthma medications during pregnancy when it is unnecessary for them to do so (i.e. patient’s asthma adequately controlled on current therapy), putting them at risk of uncontrolled asthma. Furthermore, lack of knowledge in regards to management of deteriorating asthma during pregnancy became evident, with over 12% of respondents being unsure about what to do. • Phase 3 (Chapter 5): By interviewing participants, it became apparent that many pregnant women were unaware of the risks of poorly controlled asthma. Consequently, they were discontinuing their current asthma therapy and increasing the risks of poor asthma control during pregnancy and poor perinatal outcomes. Reasons behind their decisions revolved around lack of support and information about what to do, concerns about the safety of the medications, past experiences, and desire for an “all natural” pregnancy. Asthma monitoring was also found to be poor or nonexistent in pregnancy. • Phase 4 (Chapters 6 and 7): MAMMA© involved many interventions by the trial pharmacist aimed at improving asthma control in the intervention participants. These included initiation of asthma action plans (n=7), restarting of preventers (n=5), initiation of preventers (n=5), increase in preventer doses (n=4) and referral to a respiratory specialist (n=1). The Asthma Control Questionnaire (ACQ) score in the intervention group (n = 29) decreased by a mean (SD) of 0.46 (1.05) at 3 months and 0.89 (0.98) at 6 months. The control group (n = 29) had a mean decrease of 0.15 (0.63) at 3 months and 0.18 (0.73) at 6 months. The difference between groups, adjusting for baseline, was -0.22 (95%CI: -0.54 to 0.10) at 3 months and -0.60 (-0.85 to -0.36) at 6 months. The difference at 6 months was statistically significant (p<0.001) and clinically significant (>0.5). No asthma-related oral corticosteroid use, hospital admissions, emergency visits or days off work were reported during the trial. Conclusion: These findings confirm the safety of preventive asthma medications, the importance of health professionals, such as pharmacists, monitoring asthma management during pregnancy, and the value of a multidisciplinary model of care involving education, regular monitoring and follow-up in routine antenatal care. This thesis has promoted more awareness of the risks of poorly controlled asthma in pregnancy and clarifies the need for future research in this area.