Respiratory viral infections in pregnant women with asthma are associated with wheezing in the first 12 months of life

Asthma in pregnancy

Background: Asthma is a frequent and potentially life-threatening disease that complicates many pregnancies. There are extensive data with regard to the diagnosis and treatment of asthma during pregnancy. Medical providers require an up-to-date summary of the critical aspects of asthma management during pregnancy. Objective: This review aimed to summarize the available data from clinical trials, cohort studies, expert opinions, and guideline recommendations with regard to asthma in pregnancy. Methods: A search through PubMed was conducted by using keywords previously mentioned and MeSH (Medical Subject Headings) terminology. Clinical trials, observational studies, expert opinions, guidelines, and other reviews were included. The quality of the studies was assessed, and data were extracted and summarized. Results: Asthma worsens in ∼40% of pregnant women, which can be associated with maternal and fetal complications. Physiologic changes in the respiratory, cardiovascular, and immune systems during pregnancy play a critical role in the manifestations of asthma. The diagnosis and the treatment of asthma are similar to that of patients who are not pregnant. Nonetheless, concern for fetal malformations, preterm birth, and low birth weight must be considered when managing pregnant patients with asthma. Importantly, cornerstones of the pharmacotherapy of asthma seem to be safe during pregnancy. Conclusion: Asthma in pregnancy is associated with adverse outcomes. Roadblocks to management include associated comorbidities, medication nonadherence, atopy, lack of education, and smoking habits. These need to be acknowledged and addressed for successful asthma management during pregnancy.

Management of Asthma Exacerbations in the Emergency Department

Asthma exacerbations occur across a wide spectrum of chronic severity; they contribute to millions of emergency department (ED) visits in both children and adults every year. Management of asthma exacerbations is an important part of the continuum of asthma care. The best strategy for ED management of an asthma exacerbation is early recognition and intervention, continuous monitoring, appropriate disposition, and, once improved, multifaceted transitional care that optimizes subacute and chronic asthma management after ED discharge. This article concisely reviews ED evaluation, treatment, disposition, and postdischarge care for patients with asthma exacerbations, based on high-quality evidence (eg, systematic reviews from the Cochrane Collaboration) and current international guidelines (eg, the National Asthma Education and Prevention Program Expert Panel Report 3, Global Initiative for Asthma, and Australian guidelines). Special populations (young children, pregnant women, and the elderly) also are addressed. Despite advances in asthma science, there remain many important evidence gaps in managing ED patients with asthma exacerbation. This article summarizes several of these controversial areas and challenges that merit further investigation.

Factors Associated with Nonadherence to Inhaled Corticosteroids for Asthma During Pregnancy

BACKGROUND

Nonadherence is common among pregnant women prescribed inhaled corticosteroids (ICS) for asthma and may have serious consequences for mother and baby. Factors associated with ICS nonadherence have not been determined in this population.

OBJECTIVES

To determine factors associated with {1} nonadherence to ICS in early-mid pregnancy (cross-sectional) and {2} persistent nonadherence to ICS during pregnancy (longitudinal).

METHODS

Data used come from 3 prospective studies (2004-2019) involving women with asthma recruited by 23 weeks' gestation (N = 1614). Demographics, asthma history, and current symptoms were assessed, and spirometry was performed at baseline and throughout pregnancy. Women self-reported current medication use and number of ICS doses missed in the past week. Nonadherence was defined as ≥20% of prescribed dosages missed in the past week (baseline) and on at least 2 occasions during follow-up (persistent). Factors associated with ICS nonadherence were examined using backward stepwise logistic regression.

RESULTS

Of 610 (38%) women prescribed ICS at baseline, 236 (39%) were classified as nonadherent. Of 612 (38%) women prescribed ICS during at least 2 follow-up visits, 149 (24%) were classified as persistent nonadherent. Factors associated with nonadherence at baseline were current or ex-smoking, non-Caucasian/non-Indigenous ethnicity, adult diagnosis of asthma, and lower lung function. Factors associated with persistent nonadherence to ICS were lower maternal age, higher parity, and no prescribed ICS at baseline.

CONCLUSION

Young multiparous non-Caucasian/non-Indigenous mothers are at increased risk of being nonadherent to ICS during pregnancy. Strategies to improve ICS nonadherence should address maternal smoking and target women who (re-)initiate ICS use in pregnancy.

Phototherapy for neonatal hyperbilirubinemia and childhood eczema, rhinitis and wheeze

BACKGROUND

The pathogenesis of allergic diseases in childhood may be attributed to influences of early environmental stimuli on fetal and neonatal immune regulation. Neonatal hyperbilirubinemia is common in the Asian population and up to 20% of infants require phototherapy. We examined the hypothesis that phototherapy for neonatal hyperbilirubinemia modulates the infant's risk of developing eczema, rhinitis and wheeze in the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort.

METHOD

Interviewers collected information on demographics, lifestyle, birth data and allergic outcomes. Atopic sensitization was assessed through skin prick testing (SPT) to aeroallergens and food allergens.

RESULTS

A total of 135 (12.8%) children underwent phototherapy for neonatal hyperbilirubinemia. Infants who underwent phototherapy were of a significantly lower mean (SD) gestational age [37.5 (2.5) weeks] compared to those who did not [38.5 (1.2) weeks p < 0.01]. A higher proportion of infants born by Caesarean section underwent phototherapy compared to those who were born vaginally (17.5% vs 10.7%, p < 0.01). There were no differences in prevalence of allergen sensitization, eczema, rhinitis and early onset wheeze with use of nebulizer in the first 5 years of life between subjects that underwent phototherapy and those that did not. There were also no associations between mean bilirubin peak levels within the phototherapy group with development of eczema, rhinitis and early onset wheeze in the first 5 years of life.

CONCLUSION

We found no evidence for a link between phototherapy for neonatal hyperbilirubinemia and childhood allergic outcomes in this prospective mother-offspring cohort.

TRIAL REGISTRATION

NCT01174875 Registered 1 July 2010, retrospectively registered.

Trends in asthma self-management skills and inhaled corticosteroid use during pregnancy and postpartum from 2004 to 2017

OBJECTIVE

Asthma exacerbations and medication non-adherence are significant clinical problems during pregnancy. While asthma self-management education is effective, the number of education sessions required to maximise asthma management knowledge and inhaler technique and whether improvements persist postpartum, are unknown. This paper describes how asthma knowledge, skills, and inhaled corticosteroid (ICS) use have changed over time.

METHODS

Data were obtained from 3 cohorts of pregnant women with asthma recruited in Newcastle, Australia between 2004 and 2017 (N = 895). Medication use, adherence, knowledge, and inhaler technique were compared between cohorts. Changes in self-management knowledge/skills and women's perception of medication risk to the fetus were assessed in 685 women with 5 assessments during pregnancy, and 95 women who had a postpartum assessment.

RESULTS

At study entry, 41%, 29%, and 38% of participants used ICS in the 2004, 2007, and 2013 cohorts, respectively (p = 0.017), with 40% non-adherence in each cohort. Self-management skills of pregnant women with asthma did not improve between 2004 and 2017 and possession of a written action plan remained low. Maximum improvements were reached by 3 sessions for medications knowledge and one session for inhaler technique, and were maintained postpartum. ICS adherence was maximally improved after one session, but not maintained postpartum. Perceived risk of asthma medications on the fetus was highest for corticosteroid-containing medication; and was significantly reduced following education.

CONCLUSIONS

There was a high prevalence of non-adherence and poor self-management skills in all cohorts. More awareness of the importance of optimal asthma management during pregnancy is warranted, since no improvements were observed over the past decade.

Asthma Outcomes and Management During Pregnancy

Asthma during pregnancy poses a common, increasingly prevalent threat to the health of women and their children. The present article reviews recent insights gained from the epidemiology of asthma during pregnancy, demonstrating the many short- and long-term risks to mother and fetus incurred by poorly controlled maternal asthma. We further discuss emerging evidence that active management of asthma during pregnancy can positively influence and perhaps completely mitigate these poor outcomes. Recent high-quality trials examining best methods for asthma treatment are reviewed and synthesized to offer an evidence-based pathway for comprehensive treatment of asthma in the outpatient setting. Safe and effective medications, as well as nonpharmacologic interventions, for asthma during pregnancy are discussed, and treatment options for related conditions of pregnancy, including depression, rhinitis, and gastroesophageal reflux, are presented. Throughout, we emphasize that an effective treatment strategy relies on a detailed patient evaluation, patient education, objective measurement of asthma control, and frequent and supportive follow-up. The cardiovascular and respiratory physiology of pregnancy is reviewed, as well as its implications for the management of patients with asthma, including patients requiring intubation and mechanical ventilation. For the situation when outpatient asthma management has failed, an approach to the critically ill pregnant patient with status asthmaticus is detailed. Multidisciplinary teams that include pulmonary specialists, obstetricians, primary care providers, nurses, pharmacists, and asthma educators improve the care of pregnant women with asthma.

Breastfeeding and perinatal exposure, and the risk of asthma and allergies

PURPOSE OF REVIEW

Exposures during the perinatal period, a phase of rapid development, may have a profound and sustained effect on disease risk. In particular, perinatal exposures may influence the development and maturation of the infant immune system and the risk of allergic disease. We aimed to summarize the current literature on perinatal exposures and the risk of asthma and allergic disease

RECENT FINDINGS

Increased risk of offspring wheeze or asthma was found for: maternal obesity and hypertension during pregnancy; febrile illness, gynaecological, and viral respiratory infections in pregnancy; exposure to bisphenol A and phthalates in pregnancy and childhood; exposure to smoking in utero; low birth weight; caesarean section and neonatal hyperbilirubinaemia. Reduced risk of offspring atopic eczema was found for hookworm infection in pregnancy and reduced risk of offspring wheeze was associated with increased pregnancy dietary intake of vitamin E and zinc. Higher levels of selenium in pregnancy were associated with less risk of asthma in genetically susceptible offspring. Early life pet ownership was associated with a decrease in atopic asthma but an increase in nonatopic asthma risk.

SUMMARY

A diverse range of exposures were associated with allergic disease risk, highlighting the susceptibility of children during the perinatal period. Clinicians should reinforce public health messages concerning maternal obesity, smoking, and breastfeeding. The infant gut microbiome is emerging as an important hypothesis, which may mediate the relationship between many perinatal exposures and allergic disease.

Respiratory Syncytial virus infection compromises asthma tolerance by recruiting interleukin-17A-producing cells via CCR6-CCL20 signaling

Asthma tolerance can be induced by breast-feeding or oral feeding with ovalbumin (OVA). Anergy or deletion of specific T cells and generation of T regulatory cells might contribute to this process. However, whether respiratory syncytial virus (RSV) infection would affect asthma tolerance is not very clear. Here, we first established asthma and oral tolerance mouse models and then analyzed airway hypersensitivity and asthma-related genes in the lung, CCR6-expressing IL-17A⁺ cells in the lungs, hilar or mesenteric lymph nodes (HLN or MLN) among control, asthmatic, tolerized, RSV infection, and RSV-infected asthmatic and tolerized groups. We also administrated CCL20 or IL-17A neutralizing antibody to RSV-infected tolerized mice to test whether RSV infection would mobilize CCR6-expressing IL-17A⁺ cells from MLN to the infected lungs. We found that tolerized mice infected with RSV developed asthma-like responses manifested by increasing airway hypersensitivity, exacerbating peribronchial inflammation, elevating lung asthma-related genes (Il17a, Mu5ac, and Gob5), accumulating CCR6-expressing IL-17A⁺ cells in the lungs and HLN with a reduction of this cell population in MLN. CCL20-CCR6 co-expression in RSV-infected tolerized MLN was reduced. Neutralization of CCL20 reduced CD3⁺CD4⁺CCR6⁺ cells in the RSV-infected tolerized HLN. Neutralization of IL-17A mitigated the compromising effects of RSV infection on asthma tolerance. Taken together, RSV infection impairs asthma tolerance by recruiting IL-17A-producing cells via CCR6-CCL20 signaling. The findings provide novel insight into exacerbation and therapeutic strategy of asthma under RSV infection.

Infective respiratory syncytial virus is present in human cord blood samples and most prevalent during winter months

Background

Human respiratory syncytial virus (RSV) remains the most common cause of severe lower respiratory tract disease amongst infants, and continues to cause annual epidemics of respiratory disease every winter worldwide. Demonstrating placental transmission of viable RSV in human samples is a major paradigm shift in respiratory routes considered likely for RSV transmission.

Methods

Droplet digital PCR (ddPCR) was used to identify RSV present in cord blood mononucleocytes (CBM). CBMs testing positive for RSV were treated with phytohemagglutinin (PHA), PHA and nitric oxide (NO) or PHA, NO and palivizumab, and co-cultured with HeLa cell monolayers. Subsequent immuno-staining for RSV was used to visualize infective viral plaques.

Results

RSV was detected in 26 of 45 samples (57.7%) by ddPCR. CBM’s collected in winter were more likely to test positive for RSV (17/21 samples, risk = 80%, OR = 7.08; 95% CI 1.80–27.80; p = 0.005) compared to non-winter months (9/24 samples, 37.5%). RSV plaques were observed in non-treated and treated co-cultured HeLa monolayers.

Conclusions

Demonstrating active RSV in CBMs suggests in utero transmission of infective virus to the fetus without causing overt disease. This is likely to have an important impact on immune development as well as future virus-host interactions, thereby warranting further investigation.

Asthma and allergic rhinitis in childhood: what's new

Novel approaches are currently offered for the diagnostic workup and therapeutic management of allergic rhinitis and asthma. New predictive biomarkers of allergy and asthma are available. Primary and secondary prevention, earlier intervention, and modification of the natural history of allergic rhinitis and asthma are being intensively investigated. This review highlights advances in the understanding of the etiology, diagnosis, and management of atopic airway diseases in childhood, as well as prenatal and early-life risk factors and strategies for prevention.

Respiratory allergies in childhood: Recent advances and future challenges

The burden of allergic airway diseases still represents a major health problem in childhood. Despite many different options are currently available for the diagnostic work-up and management, the overall disease control in terms of impact on quality of life, morbidity and mortality, is not yet satisfactory. The extreme variability of individual risk factors and severity determinants may account for it. On the other side, the knowledge of the multifaceted allergy background could pave the way to primary prevention, early intervention and disease course modification. In fact, most of current research is focusing on the identification of biological and clinical predictive markers of allergy and asthma onset. This review aims at summarizing the latest achievements concerning the complex inter-relation between genetic predisposition and environmental factors, and their impact on prevention strategies and early identification of at risk subjects. An update on the diagnostic and monitoring tools as well as an insight into the newest treatments options is also provided.

Allergic airway diseases in childhood: an update

Complex multifactorial diseases such as allergic rhinitis and asthma are not only becoming an increasing burden to healthcare systems, but especially affect the life quality of children and families suffering from their allergic symptoms. Also physicians are challenged by the multifaceted diseases as their work involves not only the often difficult decisions on case-adapted diagnostics, treatment, and monitoring, but also possible preventive measures. This review gives an outline of the latest scientific developments related to the etiology, diagnosis, and management of allergic airway diseases in childhood, as well as prenatal and early life risk factors and strategies for prevention.

Respiratory viral infections in pregnant women with asthma are associated with wheezing in the first 12 months of life

BACKGROUND

There are few studies investigating the relationship between respiratory viral infection in pregnancy and asthma in the offspring, and none among mothers with asthma. Infants of mothers with asthma are more likely to wheeze and have a higher risk of developing asthma than infants of non-asthmatic mothers.

METHODS

A prospective cohort study of viral infection in pregnancy was conducted between 2007 and 2009, and a subgroup of infants of mothers with asthma was followed up at 6 and 12 months of age. During common colds, nasal and throat swabs were collected from mothers and respiratory viruses detected by polymerase chain reaction. Respiratory health of infants was assessed by parent-completed questionnaire.

RESULTS

Twelve-month-old infants whose mothers had confirmed viral infections in pregnancy (n = 26) reported more frequent wheeze (40% had 4-12 wheeze attacks compared with 0%), sleep disturbed by wheeze (1 night per week or more in 60% vs. 11%), beta agonist treatment for wheeze (27% vs. 0%), prolonged colds (2 wk or longer 31% vs. 0%), more eczema (40% vs. 6.3%), and parent-perceived asthma (32% vs. 0%), compared with infants whose mothers had common colds without laboratory-confirmed viral infection (n = 16).

CONCLUSIONS

This study demonstrates a relationship between maternal respiratory viral infection in pregnancy and wheezing illness in infants of mothers with asthma. Viral infections are the most common cause of asthma exacerbations in pregnancy, and infants of asthmatic mothers are at increased risk of asthma themselves. Further research is needed to elucidate the mechanisms involved.