Change in FEV1 and Feno Measurements as Predictors of Future Asthma Outcomes in Children

The role of 14-3-3β in acute asthma in children and analysis of the risk factors for asthma exacerbation

OBJECTIVE

To investigate the role of 14-3-3β in acute asthma exacerbations in children and analyze the risk factors for asthma exacerbations.

METHODS

This study recruited 101 children with acute asthma exacerbations, 101 children with stable asthma, and 65 healthy children. Serum 14-3-3β was compared among the three groups. Factors such as asthma family history, skin prick test, serum-specific IgE test, coinfections, and clinical indicators (FeNO, FEV1, white blood cells, eosinophils, and serum IgE level) were compared between the asthma groups. Risk factors associated with acute asthma exacerbations were identified using multivariate logistic regression models. ROC curve was drawn to determine the diagnostic sensitivity and specificity of 14-3-3β.

RESULTS

Serum 14-3-3β was significantly greater in the acute asthma group than in the stable asthma and control groups. Serum 14-3-3β was higher in severe acute asthma group than in mild-moderate asthma group. There were no significant differences in serum 14-3-3β levels between stable asthma and control groups (p > .05). Multivariate logistic regression analysis revealed that serum 14-3-3β level, FeNO, coinfection, and FEV1 z-score significantly increased the odds of acute asthma exacerbations in children. The optimal 14-3-3β cutoff value (39.79 ng/mL), had a sensitivity of 69.3% and specificity of 94.1% for predicting acute asthma exacerbations.

CONCLUSIONS

14-3-3β is elevated in children with acute exacerbations of asthma, and increases with exacerbation severity. 14-3-3β, FeNO, FEV1, and coinfection could be independent risk factors for predicting asthma exacerbations. The optimal 14-3-3β cutoff value for predicting asthma exacerbations was 39.79 ng/mL.

The change of FeNO is correlated with asthma control and lung function

Objective

To investigate the changes in fractional exhaled nitric oxide (FeNO) after treatment and the association between FeNO changes and the prognosis and lung function of children with asthma.

Methods

A total of 144 children newly enrolled with non-standardized treatment of asthma were recruited between September 2020 and December 2021. The children were divided into two groups according to the initial FeNO (0 day), and the changes in FeNO after Budesonide/Formoterol Inhalation Powder Mist (B/FIPM) treatment were observed in different subgroups in correlation with future outcomes after 1 year (well controlled or partly controlled) and lung function.

Results

The study showed that B/FIPM therapy significantly reduced FeNO levels and eosinophils (EOS) counts, improving pulmonary function (P < 0.01). FeNO levels significantly decreased in the well controlled group after 1 week treatment but not after 2 weeks. The partly controlled group showed sustained benefits after 2 weeks treatment (P < 0.01). Besides, among the patients with initial FeNO ≤35 ppb, the proportion of well controlled outcome was significantly higher in the group of ΔFeNO >0 (72.73 %) than that in the ΔFeNO ≤0 group (53.85 %) (P = 0.042).

Conclusion

B/FIPM is effective in reducing FeNO levels and EOS counts and restoring lung function in children with asthma. In addition, post-treatment changes in FeNO were predictive of prognosis and correlated with post-treatment lung function.

Type 2 Inflammation and Asthma in Children: A Narrative Review

Increased understanding of the underlying pathophysiology has highlighted the heterogeneity of asthma and identified that most children with asthma have type 2 inflammation with elevated biomarkers, such as blood eosinophils and/or fractional exhaled nitric oxide. Although in the past most of these children may have been categorized as having allergic asthma, identifying the type 2 inflammatory phenotype provides a mechanism to explain both allergic and non-allergic triggers in pediatric patients with asthma. Most children achieve control with low to medium doses of inhaled corticosteroids. However, in a small but significant proportion of children, asthma remains uncontrolled despite maximum conventional treatment, with an increased risk of severe exacerbations. In this review, we focus on the role of type 2 inflammation and allergic processes in children with asthma, together with evidence of the efficacy of available treatment options for those who experience severe symptoms.

A retrospective analysis of the clinical efficacy in patients treated with Alternaria alternata and Dermatophagoides farinae immunotherapy

Background

The clinical efficacy of allergen-specific immunotherapy (AIT) for Alternaria alternata (A. alt) and Dermatophagoides farinae (Der f) extracts remains largely unknown in China. We sought to retrospectively evaluate the efficacy caused by AIT agents manufactured in China of patients who are sensitized to A. alt and Der f.

Methods

Patients aged 5-27 years with asthma and perennial allergic rhinitis (AR), and AIT with A. alt and Der f were recruited, and then classified into two groups: A. alt-AIT (n = 31) and A. alt + Der f-AIT group (n = 39). All data were gathered retrospectively, including biological parameters, pulmonary function, and symptom and medication scores.

Results

70 patients who underwent A. alt and Der f AIT were enrolled. A significant improvement was observed in the values of FEV1% (P < 0.0001) and MEF 25 (P = 0.023) of lung function. Both the rhinitis symptoms and combined symptoms and medication scores for asthma decreased after AIT (by 45.3% and 80.3%, respectively, P < 0.0001 for each). Nearly 67% improvement rate (P < 0.0001) occurred in rhinoconjunctivitis quality of life, and a great increase existed in Asthma Control Test (ACT) score (P < 0.0001) after at least 1 year AIT, although there were no significant changes between these two groups. Besides, no significance was displayed in specific IgE to different allergens.

Conclusion

AIT with A. alt and Der f extracts had clinical efficacy for many patients in China, with a reduction of symptom and medication scores, and great improvement in spirometry function.

Doxofylline as a steroid-sparing treatment in Mexican children with asthma

OBJECTIVE

The aim of this pilot study was to assess the efficacy of doxofylline as an ICS-sparing agent in the treatment of Mexican children with asthma.

METHODS

10-week, open-label, crossover, pilot study, we examined the steroid-sparing effect of doxofylline in Mexican children with asthma. Patients aged 6-16 years treated with inhaled corticosteroids (ICS) for at least 8 wk before enrollment were divided randomly into two groups at the baseline visit. Group A (n = 31) received doxofylline (18 mg/kg/day) plus standard-dose budesonide (D + SDB) for the first 4-week period followed by doxofylline plus reduced-dose budesonide (D + RDB) for the second 4-week period. Group B (n = 30) received D + RDB followed by D + SDB. Clinical outcomes assessed included lung function (forced expiratory volume; in 1 s, FEV1), fractional exhaled nitric oxide (FeNO), asthma control, number of exacerbations and use of rescue medication (salbutamol).

RESULTS

It was shown that combined use of doxofylline and ICS may allow children with asthma to reduce their daily dose of ICS while maintaining lung function and improving asthma control (p = 0.008). There were few asthma exacerbations and only one patient required treatment with systemic corticosteroids. Rescue medication use decreased significantly in patients receiving D + SDB during the first 4-week period.

CONCLUSIONS

Our results suggest that doxofylline may be a steroid-sparing treatment in asthma, but longer-term, controlled studies are needed to confirm these observations.

Risk factor analysis and nomogram for predicting poor symptom control in smoking asthmatics

BACKGROUND

Smoking induces and modifies the airway immune response, accelerating the decline of asthmatics' lung function and severely affecting asthma symptoms' control level. To assess the prognosis of asthmatics who smoke and to provide reasonable recommendations for treatment, we constructed a nomogram prediction model.

METHODS

General and clinical data were collected from April to September 2021 from smoking asthmatics aged ≥14 years attending the People's Hospital of Zhengzhou University. Patients were followed up regularly by telephone or outpatient visits, and their medication and follow-up visits were recorded during the 6-months follow-up visit, as well as their asthma control levels after 6 months (asthma control questionnaire-5, ACQ-5). The study employed R4.2.2 software to conduct univariate and multivariate logistic regression analyses to identify independent risk factors for 'poorly controlled asthma' (ACQ>0.75) as the outcome variable. Subsequently, a nomogram prediction model was constructed. Internal validation was used to test the reproducibility of the model. The model efficacy was evaluated using the consistency index (C-index), receiver operating characteristic (ROC) curve, calibration curve, and decision curve.

RESULTS

Invitations were sent to 231 asthmatics who smoked. A total of 202 participants responded, resulting in a final total of 190 participants included in the model development. The nomogram established five independent risk factors (P<0.05): FEV1%pred, smoking index (100), comorbidities situations, medication regimen, and good or poor medication adherence. The area under curve (AUC) of the modeling set was 0.824(95%CI 0.765-0.884), suggesting that the nomogram has a high ability to distinguish poor asthma control in smoking asthmatics after 6 months. The calibration curve showed a C-index of 0.824 for the modeling set and a C-index of 0.792 for the self-validation set formed by 1000 bootstrap sampling, which means that the prediction probability of the model was consistent with reality. Decision curve analysis (DCA) of the nomogram revealed that the net benefit was higher when the risk threshold probability for poor asthma control was 4.5 - 93.9%.

CONCLUSIONS

FEV1%pred, smoking index (100), comorbidities situations, medication regimen, and medication adherence were identified as independent risk factors for poor asthma control after 6 months in smoking asthmatics. The nomogram established based on these findings can effectively predict relevant risk and provide clinicians with a reference to identify the poorly controlled population with smoking asthma as early as possible, and to select a better therapeutic regimen. Meanwhile, it can effectively improve the medication adherence and the degree of attention to complications in smoking asthma patients.

Objective monitoring tools for improved management of childhood asthma

Asthma is a common chronic disease amongst children. Epidemiological studies showed that the mortality rate of asthma in children is still high worldwide. Asthma control is therefore essential to minimize asthma exacerbations, which can be fatal if the condition is poorly controlled. Frequent monitoring could help to detect asthma progression and ensure treatment effectiveness. Although subjective asthma monitoring tools are available, the results vary as they rely on patients' self-perception. Emerging evidence suggests several objective tools could have the potential for monitoring purposes. However, there is no consensus to standardise the use of objective monitoring tools. In this review, we start with the prevalence and severity of childhood asthma worldwide. Then, we detail the latest available objective monitoring tools, focusing on their effectiveness in paediatric asthma management. Publications of spirometry, fractional exhaled nitric oxide (FeNO), hyperresponsiveness tests and electronic monitoring devices (EMDs) between 2016 and 2023 were included. The potential advantages and limitations of each tool were also discussed. Overall, this review provides a summary for researchers dedicated to further improving objective paediatric asthma monitoring and provides insights for clinicians to incorporate different objective monitoring tools in clinical practices.

Recommendations for asthma monitoring in children: A PeARL document endorsed by APAPARI, EAACI, INTERASMA, REG, and WAO

Monitoring is a major component of asthma management in children. Regular monitoring allows for diagnosis confirmation, treatment optimization, and natural history review. Numerous factors that may affect disease activity and patient well-being need to be monitored: response and adherence to treatment, disease control, disease progression, comorbidities, quality of life, medication side-effects, allergen and irritant exposures, diet and more. However, the prioritization of such factors and the selection of relevant assessment tools is an unmet need. Furthermore, rapidly developing technologies promise new opportunities for closer, or even "real-time," monitoring between visits. Following an approach that included needs assessment, evidence appraisal, and Delphi consensus, the PeARL Think Tank, in collaboration with major international professional and patient organizations, has developed a set of 24 recommendations on pediatric asthma monitoring, to support healthcare professionals in decision-making and care pathway design.

Medication Adherence in Children with Asthma

Asthma is the most common chronic disease in childhood. If untreated, asthma can lead to debilitating daily symptoms which affect quality of life, but more importantly can lead to fatal asthma attacks which unfortunately still occur globally. The most effective treatment strategy for controlling asthma is for the patient to follow a personalised asthma action plan (PAAP) which will invariably include regular use of an inhaled corticosteroid. To examine medication adherence in children with asthma, we collated recent evidence from systematic reviews in this area to address the following 5 key questions; What is adherence? Is there evidence that children are not adhering to preventer medication? Why is adherence poor and what are the barriers to adherence? Does good adherence improve outcomes in asthma? And lastly, how can treatment adherence be improved?

Impact of Lung Function on Asthma Exacerbation Rates in Children Treated with Dupilumab: The VOYAGE Study

Background

Severe, uncontrolled asthma and asthma exacerbations in children are associated with abnormal lung function and airway development, and increased risk of chronic obstructive lung disease in adulthood. The rationale for this post hoc analysis was to explore the relationship between changes in asthma exacerbation rates and lung function in children treated with dupilumab.

Methods

This post hoc analysis included children aged 6 to 11 years with uncontrolled, moderate-to-severe type 2 asthma (blood eosinophils ≥150 cells/μL or fractional exhaled nitric oxide ≥20 ppb) who received dupilumab or placebo in the phase 3 LIBERTY ASTHMA VOYAGE study (NCT02948959). Endpoints were the proportion of patients achieving clinically meaningful improvements (≥5% or ≥10%) in pre-bronchodilator percent-predicted forced expiratory volume in 1 second (ppFEV1) by Week 12, annualized severe asthma exacerbation rates from Week 12-52, and mean change from baseline in ppFEV1 to Week 12.

Results

At Week 12 of VOYAGE, 141/236 (60%) of children treated with dupilumab and 57/114 (50%) of children receiving placebo showed improvements of ≥5% in ppFEV1; 106/236 (45%) children receiving dupilumab and 36/114 (32%) receiving placebo achieved improvements in ppFEV1 ≥10%. During the Week 12-52 treatment period, dupilumab vs placebo significantly reduced severe exacerbation rates in all subgroups by 52-60% (all P<0.05). Dupilumab treatment resulted in rapid and sustained improvements in ppFEV1 (Week 12 least squares mean difference [95% CI] vs placebo: 3.54 [0.30, 6.78] percentage points; P=0.03) in children who achieved improvements of ≥5%.

Conclusion

Dupilumab vs placebo significantly improved pre-bronchodilator ppFEV1, with a higher proportion of patients achieving a clinically meaningful response at Week 12. Dupilumab also significantly reduced severe exacerbation rates, independent of pre-bronchodilator ppFEV1 response at Week 12.

Trial Registration

NCT02948959.

Prediction of Asthma Exacerbations in Children

Asthma exacerbations are common in asthmatic children, even among those with good disease control. Asthma attacks result in the children and their parents missing school and work days; limit the patient's social and physical activities; and lead to emergency department visits, hospital admissions, or even fatal events. Thus, the prompt identification of asthmatic children at risk for exacerbation is crucial, as it may allow for proactive measures that could prevent these episodes. Children prone to asthma exacerbation are a heterogeneous group; various demographic factors such as younger age, ethnic group, low family income, clinical parameters (history of an exacerbation in the past 12 months, poor asthma control, poor adherence to treatment, comorbidities), Th2 inflammation, and environmental exposures (pollutants, stress, viral and bacterial pathogens) determine the risk of a future exacerbation and should be carefully considered. This paper aims to review the existing evidence regarding the predictors of asthma exacerbations in children and offer practical monitoring guidance for promptly recognizing patients at risk.

Use of exhaled nitric oxide in the diagnosis and monitoring of childhood asthma: myth or maxim?

Asthma is a common condition in children. This review describes the evidence from the literature and international asthma guidelines for using fractional exhaled nitric oxide (FENO) in the diagnosis and monitoring of childhood asthma. The accuracy of FENO measuring devices could be further improved, the difference in FENO results between devices are equivalent to what is considered a clinically important difference. For diagnosing asthma no guideline currently recommends FENO is used as the first test, but many recommend FENO as part of a series of tests. A cut-off of 35 ppb is widely recommended as being supportive of an asthma diagnosis, but evidence from children at risk of asthma suggests that a lower threshold of 25 ppb may be more appropriate. Nine randomised clinical trials including 1885 children have added FENO to usual asthma care and find that exacerbations are reduced when care is guided by FENO (OR for exacerbation compared to usual care 0.77, 95% CI 0.62-0.94). What is not clear is what cut-off(s) of FENO should be used to trigger a change in treatment. After 30 years of intensive research there is not sufficient evidence to recommend FENO for routine diagnosing and monitoring asthma in children.

Educational aims

To give the reader an overview of literature that supports and does not support the role of FENO in diagnosing asthma in children.To give the reader an overview of literature that supports and does not support the role of FENO in monitoring asthma in children.To give the reader an understanding of the role of FENO in international guidelines for diagnosing and monitoring asthma in children.

Asthma symptoms, spirometry and air pollution exposure in schoolchildren in an informal settlement and an affluent area of Nairobi, Kenya

BACKGROUND

Although 1 billion people live in informal (slum) settlements, the consequences for respiratory health of living in these settlements remain largely unknown. This study investigated whether children living in an informal settlement in Nairobi, Kenya are at increased risk of asthma symptoms.

METHODS

Children attending schools in Mukuru (an informal settlement in Nairobi) and a more affluent area (Buruburu) were compared. Questionnaires quantified respiratory symptoms and environmental exposures; spirometry was performed; personal exposure to particulate matter (PM2.5) was estimated.

RESULTS

2373 children participated, 1277 in Mukuru (median age, IQR 11, 9-13 years, 53% girls), and 1096 in Buruburu (10, 8-12 years, 52% girls). Mukuru schoolchildren were from less affluent homes, had greater exposure to pollution sources and PM2.5. When compared with Buruburu schoolchildren, Mukuru schoolchildren had a greater prevalence of symptoms, 'current wheeze' (9.5% vs 6.4%, p=0.007) and 'trouble breathing' (16.3% vs 12.6%, p=0.01), and these symptoms were more severe and problematic. Diagnosed asthma was more common in Buruburu (2.8% vs 1.2%, p=0.004). Spirometry did not differ between Mukuru and Buruburu. Regardless of community, significant adverse associations were observed with self-reported exposure to 'vapours, dusts, gases, fumes', mosquito coil burning, adult smoker(s) in the home, refuse burning near homes and residential proximity to roads.

CONCLUSION

Children living in informal settlements are more likely to develop wheezing symptoms consistent with asthma that are more severe but less likely to be diagnosed as asthma. Self-reported but not objectively measured air pollution exposure was associated with increased risk of asthma symptoms.

Predictors of asthma control differ from predictors of asthma attacks in children: The Swiss Paediatric Airway Cohort

BACKGROUND

It is unclear if predictors of asthma attacks are the same as those of asthma symptom control in children.

OBJECTIVE

We evaluated predictors for these two outcomes in a clinical cohort study.

METHODS

The Swiss Paediatric Airway Cohort (SPAC) is a multicentre prospective clinical cohort of children referred to paediatric pulmonologists. This analysis included 516 children (5-16 years old) diagnosed with asthma. At baseline, we collected sociodemographic information, symptoms, personal and family history and environmental exposures from a parental baseline questionnaire, and treatment and test results from hospital records. Outcomes were assessed 1 year later by parental questionnaire: asthma control in the last 4 weeks as defined by GINA guidelines, and asthma attacks defined as any unscheduled visit for asthma in the past year. We used logistic regression to identify and compare predictors for suboptimal asthma control and asthma attacks.

RESULTS

At follow-up, 114/516 children (22%), reported suboptimal asthma control, and 114 (22%) an incident asthma attack. Only 37 (7%) reported both. Suboptimal asthma control was associated with poor symptom control at baseline (e.g. ≥1 night wheeze/week OR: 3.2; 95% CI: 1.7-6), wheeze triggered by allergens (2.2; 1.4-3.3), colds (2.3; 1.4-3.6) and exercise (3.2; 2-5), a more intense treatment at baseline (2.4; 1.3-4.4 for Step 3 vs. 1), history of preschool (2.6; 1.5-4.4) and persistent wheeze (2; 1.4-3.2), and exposure to tobacco smoke (1.7; 1-2.6). Incident asthma attacks were associated with previous episodes of severe wheeze (2; 1.2-3.3) and asthma attacks (2.8; 1.6-5 for emergency care visits), younger age (0.8; 0.8-0.9 per 1 year) and non-Swiss origin (0.3; 0.2-0.5 for Swiss origin). Lung function, exhaled nitric oxide (FeNO) and allergic sensitization at baseline were not associated with control or attacks.

CONCLUSION

Children at risk of long-term suboptimal asthma control differ from those at risk of attacks. Prediction tools and preventive efforts should differentiate these two asthma outcomes.

Can the Chinese study on the normal range of FeNO in children evaluate standardized asthma treatment efficacy in 6- to 12-year-old children?

Objective

By examining fractional exhaled nitric oxide (FeNO) levels and performing pulmonary function testing, this study explored whether the multicenter study on the normal range of FeNO in children in China can be used to evaluate standardized treatment efficacy in 6- to 12-year-old children with asthma.

Methods

A total of 115 children aged 6-12 years old who were first diagnosed with asthma and received standardized asthma treatment from April 2018 to July 2022 were selected. According to the FeNO level at the first visit, the subjects were divided into different high- and low-FeNO groups according to the American Thoracic Society (ATS) guidelines and the Chinese multicenter study recommendations. The consistency of the two grouping methods and the differences between the high- and low-FeNO groups were compared after standardized treatment. The grouping method that was the most suitable for children in the cross group was discussed.

Results

(i) There was fair consistency between the Chinese multicenter study recommendations and the ATS guidelines regarding the classification of high- and low-FeNO groups (Kappa = 0.338). (ii) Repeated-measures ANOVA showed that the level of improvement in FVC%, FEV1%, FEF25%, FEF50%, and FeNO in the American high- and low-FeNO groups differed with the duration of therapy (P < 0.05), however, there was no significant difference between the Chinese groups. (iii) FEV1% and FeNO improved more after treatment in the fixed high-FeNO group than in the cross group (P < 0.05).

Conclusion

The Chinese multicenter study on the normal range of FeNO in children in China has a limited role in evaluating standardized asthma treatment efficacy in 6- to 12-year-old children. The ATS guidelines are currently recommended for clinical assessment of asthma treatment efficacy.

Routine FEV1 measurement is essential in diagnosis and monitoring of childhood asthma: myth or maxim?

Childhood asthma is a common condition in children. This review describes the evidence from seven asthma guidelines for using spirometry in the diagnosis and monitoring of childhood asthma. All guidelines recommend spirometry as the primary test to be performed for diagnosing asthma in children aged >5 years. Spirometry is often normal in children with asthma. Guidelines are not consistent with respect to whether forced expiratory volume in 1 s (FEV1) or FEV1/forced vital capacity (FVC) should be measured, or their threshold for "abnormal" spirometry, and we describe the sensitivity and specificity for these different cut-offs. The role of spirometry in monitoring asthma is less clear in the guidelines, and some do not suggest spirometry should be done. There is no consensus on what spirometric measurement should be used, how often it should be measured and what is a minimum clinically important change in spirometry. The role of spirometry in diagnosing asthma is more clearly established when compared to its role in monitoring asthma. The potential of spirometry to aid decision making for asthma diagnosis and monitoring in children remains to be fully evaluated.

Educational aims

To provide knowledge of the commonly used guidelines for asthma diagnosis and management.To give insight into the opportunities and challenges in using spirometry to diagnose and monitor asthma in children.To provide an understanding of the precision of spirometry for diagnosing asthma.

Clinical performance of spirometry and respiratory oscillometry for prediction of severe exacerbations in schoolchildren with asthma

OBJECTIVE

To determine the performance of spirometry and respiratory oscillometry (RO) in the prediction of severe asthma exacerbations (SAEs) in children.

METHODS

In a prospective study, 148 children (age 6-14 years) with asthma were assessed with RO, spirometry and a bronchodilator (BD) test. Based on the findings of spirometry and the BD test, they were classified into three phenotypes: air trapping (AT), airflow limitation (AFL) and normal. Twelve weeks later, they were re-evaluated in relation to the occurrence of SAEs. We analysed the performance of RO, spirometry and AT/AFL phenotypes for prediction of SAEs by means of positive and negative likelihood ratios, ROC curves with the corresponding areas under the curve (AUCs) and a multivariate analysis adjusted for potential confounders.

RESULTS

During the follow-up, 7.4% of patients had SAEs, and there were differences between phenotypes (normal, 2.4%; AFL, 17.9%; AT, 22.2%, P = .005). The best AUC corresponded to the forced expiratory flow between 25% and 75% of vital capacity (FEF_25-75): 0.787; 95% confidence interval, 0.600-0.973. Other significant AUCs were those for the reactance area (AX), forced expiratory volume in the first second (FEV₁), the post-BD change in forced vital capacity (FVC), and the FEV₁/FVC ratio. All of the variables had a low sensitivity for prediction of SAEs. The AT phenotype had the best specificity (93.8%; 95% CI, 87.9-97.0), but the positive and negative likelihood ratios were both significant only for the FEF_25-75. In the multivariate analysis, only some spirometry parameters were significative for prediction of SAEs (AT phenotype, FEF_25-75 and FEV₁/FVC).

CONCLUSIONS

Spirometry performed better than RO for prediction of SAEs in the medium term in schoolchildren with asthma.

Update on the Role of FeNO in Asthma Management

Asthma is a heterogenous disorder characterized by presence of different phenotypes and endotypes. Up to 10% of the individuals suffer from severe asthma and are at increased risk of morbidity and mortality. Fractional exhaled nitric oxide (FeNO) is a cost-effective, point of care biomarker that is used to detect type 2 airway inflammation. Guidelines have proposed to measure FeNO as an adjunct to diagnostic evaluation in individuals with suspected asthma and to monitor airway inflammation. FeNO has lower sensitivity, suggesting that it may not be a good biomarker to rule out asthma. FeNO may also be used to predict response to inhaled corticosteroids, predict adherence and deciding on biologic therapy. Higher levels of FeNO have been associated with lower lung function and increased risk for future asthma exacerbations and its predictive value increases when combined with other standard measurements of asthma assessment.

Asthma medication adherence and exacerbations and lung function in children managed in Leicester primary care

Poor adherence to asthma preventer medication is associated with life-threatening asthma attacks. The quality and outcomes framework mandated primary care annual asthma review does not include adherence monitoring and the effect of poor adherence on lung function in paediatric primary care patients is unknown. The aim was to investigate the link between inhaled corticosteroid (ICS) adherence and spirometry, fraction of exhaled nitric oxide (FeNO) and asthma control in asthmatic school-age children in this cross-sectional observational study involving three Leicestershire general practices. Children 5-16 years on the practice's asthma registers, were invited for a routine annual asthma review between August 2018 and August 2019. Prescription and clinical data were extracted from practice databases. Spirometry, bronchodilator reversibility (BDR) and FeNO testing were performed as part of the review. 130 of 205 eligible children (63.4%) attended their review. Mean adherence to ICS was 36.2% (SEM 2.1%) and only 14.6% of children had good adherence (≥75% prescriptions issued). We found no differences in asthma exacerbations in the preceding 12 months between the adherence quartiles. 28.6% of children in the lowest and 5.6% in the highest adherence quartile had BDR ≥ 12% but this was not statistically significant (p = 0.55). A single high FeNO value did not predict adherence to ICS. Adherence to ICS in children with asthma in primary care is poor. The link between adherence to ICS and asthma exacerbations, spirometry and FeNO is complex but knowledge of adherence to ICS is critical in the management of children with asthma.

Association of fractional exhaled nitric oxide with asthma morbidity in urban minority children

OBJECTIVE

Fractional exhaled nitric oxide (FeNO) is a well-established measure of allergic airway inflammation and possible useful adjunct disease management tool. We investigated the association of baseline and follow-up FeNO measurements with disease burden in minority children with persistent asthma.

METHODS

A retrospective chart review was conducted on 352 African American and Hispanic children seen at an urban Asthma Center in Bronx, NY. Demographic, clinical characteristics, and pulmonary function tests (PFTs) were compared between children with low, intermediate, and high baseline FeNO levels. Among 95 children with subsequent follow up visits, associations of change in FeNO with demographics, clinical characteristics, and PFTs were examined using mixed effects linear regression models.

RESULTS

A higher proportion of children with intermediate (54%) and high FeNO (58%) levels had lower airways obstruction compared to those with low FeNO levels (33%). Children with intermediate FeNO levels had more annual hospitalizations (2.8 ± 6.2) compared to those with low and high FeNO levels (1.3 ± 2.8 and 1.3 ± 2.5). These associations did not differ between ethnicities. An increase in FeNO over time was associated with higher BMI z-scores (β = 6.2, 95% CI: 1.0 to 11.4) and two or more hospitalizations in the past year (β = 16.1, 95% CI: 1.5 to 30.8).

CONCLUSIONS

Intermediate and high FeNO levels are associated with lower airways obstruction and hospitalizations. Initial and serial FeNO measurements can be a useful adjunctive tool in identifying asthma-related morbidity in urban African American and Hispanic children.

Asthma Attacks in Children-Challenges and Opportunities

Asthma is the most common chronic disease of childhood worldwide, and is responsible for significant morbidity and mortality in children and young people (CYP). Given the inherent dangers of a child experiencing even a single asthma attack, it is essential to identify and manage modifiable risk factors at every clinical opportunity. Following an attack, there is an opportunity to prevent future attacks by assessing compliance and optimizing asthma control. Careful questioning will allow physicians to identify asthma triggers, barriers to good asthma control, and health beliefs or socioeconomic obstacles that may have contributed to this attack. The vast majority of children with asthma can achieve good symptom control with appropriate use of low-dose inhaled corticosteroids.

Associations and dose-response relationships between different kinds of urine polycyclic aromatic hydrocarbons metabolites and adult lung functions

Associations and dose-response relationships between different kinds of urine polycyclic aromatic hydrocarbons (PAHs) metabolites and lung functions in general American adults were unknown. Data from the National Health and Nutrition Examination Survey database of the 2009-2012 cycles were used. The independent variables were urine PAHs adjusted for urine creatinine, including 1-hydroxynaphthalene (1-NAP), 2-hydroxynaphthalene (2-NAP), 3-hydroxyfluorene (3-FLU), 2-hydroxyfluorene (2-FLU), 3-hydroxyphenanthrene (3-PHE), 1-hydroxyphenanthrene (1-PHE), 2-hydroxyphenanthrene (2-PHE), 1-hydroxypyrene (1-PYR), and 9-hydroxyfluorene (9-FLU). The dependent variables were lung function indices including the forced vital capacity (FVC), the 1st second of a forceful exhalation (FEV₁), the ratio of FEV₁/FVC, the forced expiratory flow rate 25-75% (FEF_25%-75%), and the fractional exhaled nitric oxide (FENO). Multivariate linear regression analyses and the restricted cubic splines were used. Except for 1-PHE and 9-FLU, FEF_25%-75% decreased in quartile (Q) 4 of all the remaining seven PAHs; FEV₁ decreased in Q4 of 2-NAP, 3-PHE, 2-PHE, and 9-FLU, with β (SE) of -121.89 (45.46), -105.21 (33.57), -143.67 (40.60), and -127.71 (37.14), respectively. FVC decreased only in Q3 of 9-FLU, with β (SE) of -142.24 (56.54); FEV₁/FVC decreased in Q4 of all PAHs except for 2-FLU. Besides, FENO decreased in Q4 of all PAHs in smokers, while in non-smokers, the results were opposite. The dose-response relationships were non-linear. In conclusion, we found that urine PAHs may relate to the changes in lung functions. Besides, smoking status had a significant influence on FENO; FENO decreased in smokers while increased in non-smokers, suggesting that PAHs exposure may relate to airway inflammation.

Long-term predictors of loss of asthma control in school-aged well-controlled children with mild to moderate asthma: A 5-year follow-up

BACKGROUND

Long-term follow-up studies establishing risk factors for loss of asthma control in well-controlled children with mild to moderate disease are lacking and are of importance for improving patient quality of life and utilization of health-care resources.

METHODS

Loss of asthma control was assessed in 146 school-aged children with well-controlled mild to moderate asthma from a Danish pediatric asthma outpatient clinic based on hospital admissions, emergency department (ED), or outpatient management of exacerbations, oral corticosteroid (OCS) use, or step-up of regular asthma treatment according to Global Initiative for Asthma (GINA) guidelines through a 5-year follow-up period. Risk factors included sex, ethnicity, age, body mass index (BMI), atopic comorbidity and predisposition, lung function, fractional exhaled nitric oxide (FeNO) level, exercise challenge test results, regular physical activity, GINA treatment step at baseline, and adherence to controller therapy.

RESULTS

A total of 27 (18%) children experienced 56 acute events defined by hospital admission, ED, or outpatient management. Risk of experiencing any acute event was increased with female sex (adjusted odds ratio, aOR = 2.4 (1.0-5.9), p = 0.047) and higher baseline GINA treatment step (aOR = 1.6 (1.1-2.5), p = 0.03). Furthermore, female sex (aOR = 6.1 (1.4-42.2), p = 0.01) and higher FeNO (aOR = 1.8 (1.0-3.2), p = 0.04) were associated with OCS prescriptions, whereas no risk factors were identified for GINA treatment step-up during the 5-year follow-up.

CONCLUSIONS

Female sex, higher FeNO, and higher baseline GINA treatment step increase the risk of long-term loss of control including acute events and OCS use in well-controlled children with mild to moderate asthma. These findings are important for primary physicians and clinicians in asthma outpatient clinics to identify seemingly well-controlled children at risk to plan more frequent follow-ups.

Childhood asthma- pathogenesis and phenotypes

In the pathogenesis of asthma in children there is a pivotal role for a type 2 inflammatory response to early life exposures or events. Interactions between infections, atopy, genetic susceptibility, and environmental exposures (such as farmyard environment, air pollution, tobacco smoke exposure) influence the development of wheezing illness and the risk for progression to asthma. The immune system, lung function and the microbiome in gut and airways develop in parallel and dysbiosis of the microbiome may be a critical factor in asthma development. Increased infant weight gain and preterm birth are other risk factors for development of asthma and reduced lung function. The complex interplay between these factors explains the heterogeneity of asthma in children. Subgroups of patients can be identified as phenotypes based on clinical parameters, or endotypes, based on a specific pathophysiological mechanism. Paediatric asthma phenotypes and endotypes may ultimately help to improve diagnosis of asthma, prediction of asthma development and treatment of individual children, based on clinical, temporal, developmental or inflammatory characteristics. Unbiased, data-driven clustering, using a multidimensional or systems biology approach may be needed to better define phenotypes. The present knowledge on inflammatory phenotypes of childhood asthma has now been successfully applied in the treatment with biologicals of children with severe therapy resistant asthma, and it is to be expected that more personalized treatment options may become available.

Treatment Decisions in Children with Asthma in a Real-Life Clinical Setting: The Swiss Paediatric Airway Cohort

BACKGROUND

Asthma treatment should be modified according to symptom control and future risk, but there are scarce data on what drives treatment adjustments in routine tertiary care.

OBJECTIVE

We studied factors that drive asthma treatment adjustment in pediatric outpatient clinics.

METHODS

We performed a cross-sectional analysis of the Swiss Paediatric Airway Cohort, a clinical cohort of 0- to 16-year-old children seen by pediatric pulmonologists. We collected information on diagnosis, treatment, lung function, and FeNO from hospital records; and on symptoms, sociodemographic, and environmental factors from a parental questionnaire. We used reported symptoms to classify asthma control and categorized treatment according to the 2020 Global Initiative for Asthma guidelines. We used multivariable logistic regression to study factors associated with treatment adjustment (step-up or down vs no change).

RESULTS

We included 551 children diagnosed with asthma (mean age, 10 years; 37% female). At the clinical visit, most children were prescribed Global Initiative for Asthma step 3 (35%). Compared with previsit treatment, 252 children remained on the same step (47%), 227 were stepped up (42%), and 58 were stepped down (11%). Female sex (adjusted odds ratio [aOR] = 1.61; 95% confidence interval [CI], 1.05-2.47), poor asthma control (aOR = 3.08; 95% CI, 1.72-5.54), and lower FEV₁ Z-score (aOR = 0.70; 95% CI, 0.56-0.86 per one Z-score increase) were independently associated with treatment step-up, and low FeNO (aOR = 2.34; 95% CI, 1.23-4.45) was associated with treatment step-down, with marked heterogeneity between clinics.

CONCLUSIONS

In this tertiary care real-life study, we identified main drivers for asthma treatment adjustment. These findings may help improve both asthma management guidelines and clinical practice.

Real-life impact of COVID-19 pandemic lockdown on the management of pediatric and adult asthma: A survey by the EAACI Asthma Section

BACKGROUND

The restrictions imposed by the COVID-19 pandemic impact heavily the management of chronic diseases like asthma. This study aimed to evaluate the management of adults and children with asthma during COVID-19-related lockdown.

METHODS

A survey was launched by the European Academy of Allergy and Clinical Immunology (EAACI) via e-mail, website, and social media to EAACI members and members of peer societies.

RESULTS

The survey was completed by 339 healthcare professionals from 52 countries. 79% of follow-up consultations were replaced by phone calls, whereas 49% of newly referred patients attended the clinic. 62%, 76%, 66%, 76%, and 87% of responders did not conduct spirometry, impulse oscillometry, bronchodilator test, FeNO, or methacholine provocation, respectively, for asthma diagnosis in adults. The numbers were similar for children. 73% of responders based the initial asthma diagnosis and the prescription of inhaled therapy on clinical parameters only. Lung function tests were used in 29% of cases to monitor asthma worsening, and only 56% of participants were recommended to their patients ambulatory peak expiratory flow (PEF) measurements. Using a 1 (not at all) to 5 (very much) scale, the responders considered that the quality of healthcare provided and the patients' asthma status had deteriorated during the lockdown with 3.2 points and 2.8 points, respectively.

CONCLUSION

Collectively, these results suggest that all necessary resources should be allocated to ensure the performance of lung function tests for initial diagnosis, whereas digital remote monitoring should be reinforced for the follow-up of children and adults with asthma.

Associations Between Gut Microbiota and Asthma Endotypes: A Cross-Sectional Study in South China Based on Patients with Newly Diagnosed Asthma

Objective

This study aimed to investigate the gut microbiome profile in different inflammatory phenotypes of treatment-naive newly diagnosed asthmatic adults, to gain insight on the associations between intestinal microbiota and phenotypic features that characterize asthma heterogeneity to develop new treatments for asthma.

Methods

Fresh stool samples were obtained from 20 healthy subjects and 47 newly diagnosed asthmatic patients prior to any interventions. The asthmatics were divided into allergic and non-allergic cohorts. Intestinal microbiota was analyzed by 16S rRNA next-generation sequencing. Demographic and clinical parameters were collected. Alpha and beta diversity analysis were calculated to detect differences within sample phylotype richness and evenness between controls and asthmatic patients. Statistically significant differences between samples were analyzed for all used metrics, and features of gut bacterial community structure were evaluated in relation to extensive clinical characteristics of asthmatic patients.

Results

Gut microbial compositions were significantly different between asthmatic and healthy groups. Alpha-diversity of the gut microbiome was significantly lower in asthmatics than in controls. The microbiome between allergic and non-allergic asthmatic patients were also different, and 28 differential species were identified. PPAR signaling pathway, carotenoid biosynthesis, and flavonoid biosynthesis were significantly positively correlated with allergy-associated clinical index, including FENO value, blood eosinophil counts, and serum IgE and IL-4 levels. A combination of Ruminococcus bromii, Brevundimonas vesicularis, and Clostridium disporicum showed an AUC of 0.743 in the specific allergic/non-allergic cohort. When integrating C. disporicum, flavone, flavonol biosynthesis, and serum IL-4 values, the AUC achieved 0.929 to classify asthmatics. At the same time, C. colinum and its associated functional pathway exhibited an AUC of 0.78 to distinguish allergic asthmatics from those without allergies.

Conclusion

We demonstrated a distinct taxonomic composition of gut microbiota in different asthmatic phenotypes, highlighting their significant relationships. Our study may support considerations of intestinal microbial signatures in delineating asthma phenotypes.

Does lung function change in the months after an asthma exacerbation in children?

BACKGROUND

There are limited data describing lung function changes in children after an asthma exacerbation. Our hypothesis was that lung function does not fully recover in children in the months following an asthma exacerbation.

METHODS

We used a data set of children with asthma where lung function (including FEV₁ , FEV₁ /FVC ratio and FEF_25-75 ) was measured at 3-month intervals over a year. Mixed-level models compared spirometry measured on two occasions 3 months apart before a single exacerbation (assessments 1 and 2) with measurements made on two occasions after the exacerbation (assessments 3 and 4), with adjustment for covariates. Changes in spirometry over a year were also analysed across those with exacerbations in no, one or more than one 3-month periods.

RESULTS

For the 113 children who had a single exacerbation, spirometry measured at assessments 1 or 2 did not differ from measurements at assessments 3 or 4 when the whole population was considered. When stratified into tertiles by change in %FEV₁ between assessments 2 and 3, those with the greater reduction were more likely to be treated with long-acting beta-agonist, but in this category, %FEV₁ at assessment 4 had returned to the value at assessment 1. %FEV₁ did not change over a 12-month period within and between the three exacerbation categories (n = 809).

CONCLUSION

One or more asthma exacerbation was not associated with a fall in lung function for the whole population. In a subset of individuals, lung function does fall after an exacerbation but returns to pre-exacerbation values after a period of months.

Systemic and breath biomarkers for asthma: an update

PURPOSE OF REVIEW

Finding suitable biomarkers to phenotype asthma, identify individuals at risk of worsening and guide treatment is highly prioritized in asthma research. We aimed to provide an analysis of currently used and upcoming biomarkers, focusing on developments published in the past 2 years.

RECENT FINDINGS

Type 2 inflammation is the most studied asthma mechanism with the most biomarkers in the pipeline. Blood eosinophils and fractional exhaled nitric oxide (FeNO) are those most used clinically. Recent developments include their ability to identify individuals at higher risk of exacerbations, faster decline in lung function and more likely to benefit from anti-IL-5 and anti-IL-4/-13 treatment. Certain patterns of urinary eicosanoid excretion also relate to type 2 inflammation. Results of recent trials investigating the use of serum periostin or dipeptidyl peptidase-4 to guide anti-IL-13 therapy were somewhat disappointing. Less is known about non-type 2 inflammation but blood neutrophils and YKL-40 may be higher in patients with evidence of non-type 2 asthma. Volatile organic compounds show promise in their ability to distinguish both eosinophilic and neutrophilic asthma.

SUMMARY

The ultimate panel of biomarkers for identification of activated inflammatory pathways and treatment strategies in asthma patients still lies in the future, particularly for non-type 2 asthma, but potential candidates are available.

Predicting Severe Asthma Exacerbations in Children: Blueprint for Today and Tomorrow

Severe asthma exacerbations are the primary cause of morbidity and mortality in children with asthma. Accurate prediction of children at risk for severe exacerbations, defined as those requiring systemic corticosteroids, emergency department visit, and/or hospitalization, would considerably reduce health care utilization and improve symptoms and quality of life. Substantial progress has been made in identifying high-risk exacerbation-prone children. Known risk factors for exacerbations include demographic characteristics (ie, low income, minority race/ethnicity), poor asthma control, environmental exposures (ie, aeroallergen exposure/sensitization, concomitant viral infection), inflammatory biomarkers, genetic polymorphisms, and markers from other "omic" technologies. The strongest risk factor for a future severe exacerbation remains having had one in the previous year. Combining risk factors into composite scores and use of advanced predictive analytic techniques such as machine learning are recent methods used to achieve stronger prediction of severe exacerbations. However, these methods are limited in prediction efficiency and are currently unable to predict children at risk for impending (within days) severe exacerbations. Thus, we provide a commentary on strategies that have potential to allow for accurate and reliable prediction of children at risk for impending exacerbations. These approaches include implementation of passive, real-time monitoring of impending exacerbation predictors, use of population health strategies, prediction of severe exacerbation responders versus nonresponders to conventional exacerbation management, and considerations for preschool-age children who can be especially high risk. Rigorous prediction and prevention of severe asthma exacerbations is needed to advance asthma management and improve the associated morbidity and mortality.

Application of exhaled nitric oxide (FeNO) in pediatric asthma

PURPOSE OF REVIEW

Fractional concentration of Nitric Oxide in the exhaled air (FeNO) is a moderately good biomarker of type-2 airway inflammation, and its measurement is feasible also in children. The available evidence is still not enough to support the routine use of FeNO to diagnose or manage asthma in every patient in clinical practice. However, its role in identifying asthma with eosinophilic inflammation is of particular interest in the management of severe asthma.

RECENT FINDINGS

In healthy subjects, FeNO levels increase with age and height, particularly in males, and are also influenced by ethnicity. FeNO measurement can support asthma diagnosis and help in predicting asthma development later in life in young children with recurrent wheezing. FeNO-guided asthma management is effective in reducing asthma exacerbations but may result in a higher daily dose of inhaled corticosteroids. FeNO can also be used as a marker to evaluate adherence to asthma treatment and predict response to different biologicals, especially Omalizumab and Dupilumab.

SUMMARY

This review outlines recent data on the application of FeNO in childhood-onset asthma diagnosis and management, as well as in phenotyping subjects with severe asthma who may benefit from monoclonal antibodies administration.

Precision medicine in severe pediatric asthma: opportunities and challenges

Purpose of review

Severe pediatric asthma exerts a substantial burden on patients, their families and society. This review provides an update on the latest insights and needs regarding the implementation of precision medicine in severe pediatric asthma.

Recent findings

Biologicals targeting underlying inflammatory pathways are increasingly available to treat children with severe asthma, holding the promise to enable precision medicine in this heterogeneous patient population with high unmet clinical needs. However, the current understanding of which child would benefit from which type or combination of biologicals is still limited, as most evidence comes from adult studies and might not be generalizable to the pediatric population. Studies in pediatric severe asthma are scarce due to the time-consuming effort to diagnose severe asthma and the challenge to recruit sufficient study participants. The application of innovative systems medicine approaches in international consortia might provide novel leads for – preferably noninvasive – new biomarkers to guide precision medicine in severe pediatric asthma.

Summary

Despite the increased availability of targeted treatments for severe pediatric asthma, clinical decision-making tools to guide these therapies are still lacking for the individual pediatric patient.

Changes in fractional exhaled nitric oxide, exhaled carbon monoxide and pulmonary function during the acute attack, treatment and remission phases of pediatric asthma

BACKGROUND

The current study aimed to explore the value of fractional exhaled nitric oxide (FeNO), exhaled carbon monoxide (eCO), and pulmonary function in the management of asthmatic children.

METHODS

One hundred children diagnosed with asthma were selected as research subjects. Patients were divided into a 3-5-year-old group and a group with children 6 years and older. They were also grouped depending on whether they had asthma alone (A0 group) or whether their asthma was complicated with allergic rhinitis (A+AR group). The FeNO, eCO levels, and pulmonary function in the acute attack period were analyzed 1 month after treatment and clinical remission period.

RESULTS

Asthmatic children demonstrated greater pulmonary dysfunction and significantly higher FeNO and eCO during the acute attack phase compared to both one month after treatment and clinical remission. The remission phase was characterized by decreased levels of FeNO and eCO and improvement of pulmonary function. The eCO levels in children aged 3-5 years old, and both FeNO and eCO levels in children 6 years and older were statistically lower during remission regardless of whether the patients had asthma alone or asthma complicated with rhinitis. However, 10% of the 100 children in the clinical remission period still demonstrated mid to high levels of FeNO. The critical value of FeNO levels during the acute period in children 6 years and older with asthma and rhinitis was 34.5 ppb (AUROC 0.814, 95% CI: 0.684-0.944) with a sensitivity of 69.2% and specificity of 93.7%.

CONCLUSIONS

Dynamic monitoring of FeNO and eCO is an effective indicator of airway inflammation and thus represents an important clinical tool in assessing the severity of asthma in children.

Does treatment guided by exhaled nitric oxide fraction improve outcomes in subgroups of children with asthma?

INTRODUCTION

Exhaled nitric oxide fraction (F _ENO), a biomarker of eosinophilic airway inflammation, may be useful to guide asthma treatment. F _ENO-guided treatment may be more effective in certain subgroups for improving asthma outcomes compared to standard treatment.

METHODS

An individual patient data analysis was performed using data from seven randomised clinical trials (RCTs) which used F _ENO to guide asthma treatment. The incidence of an asthma exacerbation and loss of control, and the time to first exacerbation and loss of control were described between five subgroups of RCT participants.

RESULTS

Data were available in 1112 RCT participants. Among those not treated with leukotriene receptor antagonists (LTRA), but not among those who were treated with LTRA, F _ENO-guided treatment was associated with reduced exacerbation risk (OR 0.68, 95% CI 0.49-0.94), longer time to first exacerbation (hazard ratio (HR) 0.76, 95% CI 0.57-0.99) and borderline reduced risk for loss of control (OR 0.70, 95% CI 0.49-1.00). Nonobese children, compared to obese children, were less likely to lose asthma control when treatment was guided by F _ENO (OR 0.69, 95% CI 0.48-0.99) and time to loss of control was longer (HR 0.77, 95% CI 0.61-0.99).

CONCLUSIONS

Asthma treatment guided by F _ENO may be more effective in achieving better asthma outcomes for patients who are not treated with LTRA and who are not obese, compared to standard practice.

Pediatric Patients of Outreach Specialist Queensland Clinics Have Lung Function Improvement Comparable to That of Tertiary Pediatric Patients

BACKGROUND

Inequitable access to quality health care contributes to the known poorer outcomes of people living in regional/remote areas (compared with urban-based), especially for First Nations people. Integration of specialist outreach services within primary care is one strategy that can reduce the inequity when modeled to the needs and available resources of target communities.

RESEARCH QUESTION

To evaluate whether respiratory outreach clinics in regional and remote Queensland are as effective as tertiary respiratory services at improving the lung function of children.

STUDY DESIGN AND METHODS

From existing databases, we obtained spirometry data of children (aged 3-18 years) seen at Indigenous-focused outreach clinics in regional and remote Queensland and Brisbane-based pediatric tertiary hospitals over the same contemporary period (October 2010 to July 2019). We compared the change in spirometry z scores (Δz) at follow-up for both groups of children.

RESULTS

Lung function significantly improved in both groups: Tertiary hospital (n = 2,249; ΔzFEV₁ = 0.22, 95% CI, 0.17 to 0.27; ΔzFVC = 0.23, 95% CI, 0.18 to 0.28); outreach (n = 252; ΔzFEV₁ = 0.35, 95% CI, 0.22 to 0.48; ΔzFVC = 0.36, 95% CI, 0.23 to 0.50). No significant intergroup differences were found in ΔzFEV₁ (0.13; 95%CI, -0.02 to 0.28; P = .10) or ΔzFVC (0.14; 95% CI, -0.02 to 0.29; P = .08) improvement from baseline. In both groups, the proportion of children with zFEV₁ > 0 at follow-up (hospital = 31.7%; outreach = 46.8%) significantly increased (hospital P = .001; outreach P = .009) from baseline (hospital = 27.2%; outreach = 35.3%). Numbers of children with zFEV₁ > 0 significantly increased for asthma and bronchiectasis outreach subgroups, and for children with asthma in the hospital-based group.

INTERPRETATION

Comparable significant lung function improvement of children was seen in Indigenous-focused outreach remote/regional clinics and paediatric tertiary hospitals. This suggests that effective clinical care is achievable within the outreach setting.

What is a clinically meaningful change in exhaled nitric oxide for children with asthma?

INTRODUCTION

Fractional exhaled nitric oxide (F_E NO) may be a useful objective measurement to guide asthma treatment. What remains uncertain is what change in F_E NO is clinically significant.

METHODS

An individual patient data analysis was performed using data from seven randomized clinical trials which used F_E NO to guide asthma treatment. The absolute and percentage intra-subject change in F_E NO measurements over "stable" and also "unstable" 3-month periods were described.

RESULTS

Data were available in 1112 randomized controlled trial participants and ≥1 stable period was present for 665 individuals. The interquartile range (IQR) and limits of agreement (LoA) for change in absolute F_E NO among individuals whose initial F_E NO was <50 parts per billion (ppb) were -7 to +9 ppb and -43 to +50 ppb, and for those with initial F_E NO ≥50 ppb IQR was -29 to +17 ppb and LoA was -80 to +76 ppb. For percentage change in F_E NO, the IQR and LoA for individuals whose initial F_E NO was <50 ppb were -33% to +51% and -157% to +215%, and for those with initial F_E NO ≥50 ppb were -33% to +35% and -159% to +192%. The variation in F_E NO values for a stable period was similar irrespective of whether it was followed by a stable or unstable period.

CONCLUSIONS

Over a 3-month period where F_E NO is initially <50 ppb, a rise of <10 ppb or of <50% (based on IQR) is unlikely to be related to asthma. When F_E NO is initially ≥50 ppb an percentage change of <50% (based on IQR) is unlikely to be asthma-related.

Culturally Appropriate Outreach Specialist Respiratory Medical Care Improves the Lung Function of Children in Regional and Remote Queensland

BACKGROUND AND OBJECTIVES

Indigenous Respiratory Outreach Care (IROC) is a culturally appropriate specialist respiratory service established to deliver multidisciplinary respiratory care to regional and remote Queensland communities. Our objective was to evaluate the impact of an outreach specialist respiratory service on the spirometry of children attending IROC clinics, particularly Indigenous children with asthma and bronchiectasis.

METHODS

Retrospective single-arm cohort study of 189 children who performed spirometry at twelve sites across regional and remote Queensland between October 2010 and December 2017. Each child's baseline spirometry was compared to their best spirometry at follow-up visit occurring within (1) 12 months of their most recent visit with at least 12 months of specialist care and; (2) each year of their first 3 years of care.

RESULTS

Forced expiratory volume in one second (FEV₁) and forced vital capacity (FVC) z-scores improved significantly across the whole group from baseline to follow-up (change in z-scores (Δz) of FEV₁ = 0.38, 95% CI 0.22, 0.53; ΔzFVC = 0.36, 95% CI 0.21, 0.51). In subgroup analyses, lung function significantly improved in Indigenous children (n = 141, ΔzFEV₁ = 0.37, 95% CI 0.17, 0.57; ΔzFVC = 0.36, 95% CI 0.17, 0.55) including those with asthma (n = 117, ΔzFEV₁ = 0.41, 95% CI 0.19, 0.64; ΔzFVC = 0.46, 95% CI 0.24, 0.68) and bronchiectasis (n = 38, ΔzFEV₁ = 0.33, 95% CI 0.07, 0.59; ΔzFVC = 0.26, 95% CI - 0.03, 0.53). Significant improvements in FEV₁ and FVC were observed within the first and second year of follow-up for Indigenous children, but not for non-Indigenous children.

CONCLUSION

The IROC model of care in regional and remote settings leads to significant lung function improvement in Indigenous children with asthma and bronchiectasis.

Fractional Exhaled Nitric Oxide (FENO) in the management of asthma: a position paper of the Italian Respiratory Society (SIP/IRS) and Italian Society of Allergy, Asthma and Clinical Immunology (SIAAIC)

Asthma prevalence in Italy is on the rise and is estimated to be over 6% of the general population. The diagnosis of asthma can be challenging and elusive, especially in children and the last two decades has brought evidences that asthma is not a single disease but consists of various phenotypes. Symptoms can be underestimated by the patient or underreported to the clinician and physical signs can be scanty. Usual objective measures, like spirometry, are necessary but sometimes not significant. Despite proper treatment, asthma can be a very severe condition (even leading to death), however new drugs have recently become available which can be very effective in its control. Since asthma is currently thought to be caused by inflammation, a direct measure of the latter can be of paramount importance. For this purpose, the measurement of Fractional Exhaled Nitric Oxide (FE_NO) has been used since the early years of the current century as a non-invasive, easy-to-assess tool useful for diagnosing and managing asthma. This SIP-IRS/SIAAIC Position Paper is a narrative review which summarizes the evidence behind the usefulness of FE_NO in the diagnosis, management and phenotypization of asthma.

Comparison of fractional exhaled nitric oxide, spirometry, and Asthma Control Test, in predicting asthma exacerbations: A prospective cohort study

Context

Fractional exhaled nitric oxide (FeNO) is a noninvasive test for airway inflammation in asthma. The usefulness of FeNO in predicting exacerbations is uncertain.

Aims

The study aims to assess and compare the ability of FeNO, spirometry, and asthma control test (ACT) in predicting future exacerbations of asthma and their correlation with each other.

Settings and Design

This prospective, cohort study was conducted at the Department of Respiratory Medicine, Kasturba Medical College, Manipal.

Materials and Methods

Adult asthma patients of age 18-65 years were included. Patients with a smoking history of >10 pack-years and those in whom spirometry was contraindicated were excluded. Patients who consented underwent FeNO and spirometry. The control of asthma was assessed using the ACT questionnaire. We captured the number of exacerbations in the follow-up period of 4 months.

Statistical Analysis Used

Mann-Whitney test was used to compare the utility of FeNO, spirometry, ACT in predicting exacerbations and Spearman's correlation coefficient was used to ascertain the correlation among them.

Results

Of 154 study patients, 28% had exacerbations. We found that there was no significant difference in FeNO in patients with and without exacerbations. The median (interquartile range [IQR]) FEV1% in the patients with and without exacerbations were 68 (55-79) and 75 (65-88), respectively (P = 0.013). The median (IQR) ACT score in patients with exacerbations was 12 (10-16) which was significantly lower than in those without exacerbation in whom it was 16 (14-18) (P = 0.003). There was a negative correlation of ACT with FeNO (Correlation coefficient: -0.167, P = 0.038). The median (IQR) FeNO level (ppb) was lower in patients who were on inhaled corticosteroid (ICS) than in the other group values being 22 (14-38) and 30 (17-58), respectively (P = 0.05).

Conclusions

In our study, FEV1% and ACT score could predict exacerbations of asthma whereas FeNO could not. FeNO level correlated inversely with ACT score. FeNO level decreased with inhaled corticosteroid usage.

Reducing Asthma Attacks in Children using Exhaled Nitric Oxide as a biomarker to inform treatment strategy: a randomised trial (RAACENO)

Background

Childhood asthma is a common condition. Currently there is no validated objective test which can be used to guide asthma treatment in children. This study tests the hypothesis that the addition of fractional exhaled nitric oxide (F_ENO) monitoring in addition to standard care reduces the number of exacerbations (or attacks) in children with asthma.

Methods

This is a multi-centre, randomised controlled study. Children will be included of age 6–16 years who have a diagnosis of asthma, currently use inhaled corticosteroids (ICSs) and have had an exacerbation in the previous 12 months. Exclusion criteria include being unable to provide F_ENO measurement at baseline assessment, having another chronic respiratory condition and being currently treated with maintenance oral steroids. Participants will be recruited in both primary and secondary care settings and will be randomised to either receive asthma treatment guided by F_ENO plus symptoms (F_ENO group) or asthma treatment guided by symptoms only (standard care group). Within the F_ENO group, different treatment decisions will be made dependent on changes in F_ENO. Participants will attend assessments 3, 6, 9 and 12 months post randomisation. The primary outcome is asthma exacerbation requiring prescription and/or use of an oral corticosteroid over 12 months as recorded by the participant/parent or in general practitioner records. Secondary outcomes include time to first attack, number of attacks, asthma control score and quality of life. Adherence to ICS treatment is objectively measured by an electronic logging device. Participants are invited to participate in a “phenotyping” assessment where skin prick reactivity and bronchodilator response are determined and a saliva sample is collected for DNA extraction. Qualitative interviews will be held with participants and research nurses. A health economic evaluation will take place.

Discussion

This study will evaluate whether F_ENO can provide an objective index to guide and stratify asthma treatment in children.

Trial registration

ISRCTN, ISRCTN67875351. Registered on 12 April 2017. Prospectively registered.