Suitability of forced expiratory volume in 1 second/forced vital capacity vs percentage of predicted forced expiratory volume in 1 second for the classification of asthma severity in adolescents

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

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.

Factors influencing negative surgical outcomes in adult pectus excavatum patients undergoing Nuss procedure

BACKGROUND

This study aimed to examine the factors associated with the negative outcomes of Nuss procedure in adult pectus excavatum (PE) patients.

METHODS

Forty-seven adult PE patients were enrolled in this study. Mimics 21.0 software (Materialise) was used to reconstruct the preoperative and postoperative three-dimensional (3D) thoracic model. The preoperative and postoperative pulmonary volumes and function parameters were compared. The diaphragm positions were localized, and the anteroposterior diameter (APD) of the thoracic cavity was calculated using neoteric methods. Binary logistic regression was used to reveal the association between clinical factors and altered pulmonary parameters.

RESULTS

Postoperative lung volumes in adult PE patients decreased significantly (P<0.001). The mean preoperative lung volume was 4,592.82±946.54 cm³, which reduced to 3,976.26±867.35 cm³ postoperatively. The rate of postoperative lung volume reduction was approximately 12.1%. Physiologically, forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and peak expiratory flow (PEF) significantly decreased after Nuss procedure, and a near 10% reduction in FVC was observed. Diaphragm elevation was positively associated with decrease in lung volumes [odds ratio (OR) =40.51; P=0.011; 95% confidence interval (CI), 2.37-692.59]. The presence of reduced thoracic APDs was significantly associated with negative pulmonary function results (OR =1.21; P=0.008; 95% CI, 1.050-1.388).

CONCLUSIONS

This study reveals that thoracic APD reduction and diaphragm elevation are associated with decreased postoperative pulmonary volumes and function in adult PE patients. Nuss procedure for adult patients with PE must be considered cautiously by thoracic surgeons, especially in patients who expect to improve their cardiopulmonary function.

129Xe MRI as a measure of clinical disease severity for pediatric asthma

BACKGROUND

Measurement of regional lung ventilation with hyperpolarized ¹²⁹Xe magnetic resonance imaging (¹²⁹Xe MRI) in pediatric asthma is poised to advance our understanding of disease mechanisms and pathophysiology in a disorder with diverse clinical phenotypes. ¹²⁹Xe MRI has not been investigated in a pediatric asthma cohort.

OBJECTIVE

We hypothesized that ¹²⁹Xe MRI is feasible and can demonstrate ventilation defects that relate to and predict clinical severity in a pediatric asthma cohort.

METHODS

Thirty-seven children (13 with severe asthma, 8 with mild/moderate asthma, 16 age-matched healthy controls) aged 6 to 17 years old were imaged with ¹²⁹Xe MRI. Ventilation defect percentage (VDP) and image reader score were calculated and compared with clinical measures at baseline and at follow-up.

RESULTS

Children with asthma had higher VDP (P = .002) and number of defects per image slice (defects/slice) (P = .0001) than children without asthma. Children with clinically severe asthma had significantly higher VDP and number of defects/slice than healthy controls. Children with asthma who had a higher number of defects/slice had a higher rate of health care utilization (r = 0.48; P = .03) and oral corticosteroid use (r = 0.43; P = .05) at baseline. Receiver-operating characteristic analysis demonstrated that the VDP and number of defects/slice were predictive of increased health care utilization, asthma, and severe asthma. VDP correlated with FEV₁ (r = -0.35; P = .04) and FEV₁/forced vital capacity ratio (r = -0.41; P = .01).

CONCLUSIONS

¹²⁹Xe MRI correlates with asthma severity, health care utilization, and oral corticosteroid use. Because delineation of clinical severity is often difficult in children, ¹²⁹Xe MRI may be an important biomarker for severity, with potential to identify children at higher risk for exacerbations and improve outcomes.

A Multicenter, Randomized, Double-Blind, Placebo-Controlled Study of the Effects of Loki zupa in Patients With Chronic Asthma

The purpose of this study was to evaluate the efficacy and safety of Uyghur medical formula Loki zupa in patients with chronic asthma. Adult patients with chronic asthma randomly received placebo or Loki zupa as add-on to inhaled corticosteroids (ICS) maintenance treatment. Loki zupa or mimics was administered orally 10 ml per time, three times a day for 8 weeks. The primary endpoints were asthma control test (ACT) score and peak expiratory flow (PEF). The secondary endpoints were acute exacerbation rate, lung function, night waking days, and symptom-free days in the near 2 weeks, Asthma Quality of Life Questionnaire (AQLQ) score and some inflammatory cytokines in peripheral blood. A total of 240 adult patients with chronic asthma were enrolled, and 218 patients were randomized to placebo (n = 109) or Loki zupa (n = 109) in addition to ICS for 8 weeks. Treatment with Loki zupa resulted in significant improvement in ACT score compared to the placebo group (p = 0.002). Furthermore, oral taken of Loki zupa increased the PEF obviously (p = 0.026). Loki zupa treatment did not improve the forced expiratory volume in 1 s (FEV₁, p = 0.131) and FEV₁/FVC compared to the placebo treatment (p = 0.805). The placebo group had higher rates of acute exacerbations than the Loki zupa group (6.3% vs. 0, p = 0.027). Subjects randomized to Loki zupa had increased daytime symptom-free days within 2 weeks than placebo (p = 0.016). However, Loki zupa had no effect on night waking days in the near 2 weeks (p = 0.369) and AQLQ score (p = 0.113). No significant effect was found on inflammatory cytokines (IL-2, IL-4, IL-5, IL-10, IL-13, IL-17, IL-33, IFN-γ, and TGF-β) between the two groups (p > 0.05). No adverse events and severe asthma exacerbations were recorded in the two groups (p > 0.05). Loki zupa add-on to standard ICS produced clinically significant improvements in ACT score, PEF, daytime symptom-free days and acute exacerbation in patients with chronic asthma.

Clinical trial: This study is registered at http://www.chictr.org.cn/ with identifier number ChiCTR-IPR-16008106.

Correlations of smoking with cumulative total dust exposure and cumulative abnormal rate of pulmonary function in coal-mine workers

The present study aimed to investigate the correlation of smoking with cumulative total dust exposure (CTE) and cumulative abnormal rate of pulmonary function in coal-mine workers. A total of 376 coal-mine workers were recruited as the observational group, while 179 healthy workers in other industries were selected as the control group. All the workers underwent pulmonary function testing to determine their forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and FEV1/FVC, in order to compare the abnormal pulmonary function between the two groups. A markedly higher number of smokers was observed in the observational group (200/376, 53.19%) when compared with the control group (72/179, 40.22%). In smokers, the abnormal rate of pulmonary function in the observational group (102/200, 51.00%) was evidently higher compared with that in the control group (19/72, 26.39%), whereas no significant difference was detected between the two groups of non-smokers (P=0.077). In addition, FVC, FEV1 and FEV1/FVC of the observational group were found to be lower compared with those in the control group, in both the smoking and non-smoking subgroups. In the smoking subgroup, FVC and FEV1 in subjects working at the coal mine for different number of years showed significant differences (all P<0.05), whereas comparison of FEV1/FVC in workers with different working durations showed no significant difference (P=0.169). However, in the non-smoking subgroup, the comparison of FVC, FEV1 and FEV1/FVC in different working duration groups also showed no significant difference (all P>0.05). Furthermore, FVC, FEV1 and FEV1/FVC in smoking coal-mine workers were negatively correlated with the dust-exposure working duration (P<0.05). CTE was also positively correlated with cumulative abnormal rate of pulmonary function in the smoking and non-smoking subgroups, while FEV1 was negatively correlated with CTE in the smoking subgroup (P=0.009). In conclusion, smoking is an important risk factor for the damage of pulmonary function in coal-mine workers, and it is positively correlated with dust-exposure time and CTE in these individuals.

High-altitude alpine therapy and lung function in asthma: systematic review and meta-analysis

We used meta-analysis to measure the effect of high-altitude climate therapy (HACT) on lung function outcomes in asthma, and systematically searched PubMed, Embase and www.elibrary.ru for publications appearing from 1970 to mid-2015. We included studies carried out with children or adults with an exposure of up to 12 weeks at an altitude of ≥1500 m above sea level. Changes in forced expiratory volume in 1 s (FEV₁), FEV₁/vital capacity ratio or peak expiratory flow rate as the HACT intervention outcomes were analysed. We included data for 907 participants (age range 4–58 years) from 21 studies, altogether including 28 substrata based on asthma type or severity. Only three of 21 included studies had high quality, whereas 93% of substudies reported lung function improvement with an overall pooled standardised mean difference (SMD) of 0.53 (95% CI 0.43–0.62). The measured effect of HACT was greater in adults (SMD 0.75, 95% CI 0.63–0.88, n=14) than in children (SMD 0.24, 95% CI 0.09–0.38, n=14). Studies at altitude >2000 m above sea level yielded the same effect as those at lower altitude. Based on a cut-point of a 0.50 change in SMD to define a meaningful clinical difference, HACT appears to have efficacy as an intervention. This extent of benefit appears to be limited to adults with asthma.

High-altitude alpine therapy may be an effective intervention to improve lung function in patients with asthmahttp://ow.ly/u3i23008vU5

Monitoring asthma in childhood: symptoms, exacerbations and quality of life

Monitoring asthma in children in clinical practice is primarily performed by reviewing disease activity (daytime and night-time symptoms, use of reliever medication, exacerbations requiring frequent use of reliever medication and urgent visits to the healthcare professional) and the impact of the disease on children's daily activities, including sports and play, in a clinical interview. In such an interview, most task force members also discuss adherence to maintenance therapy and the patients' (and parents') views and beliefs on the goals of treatment and the amount of treatment required to achieve those goals. Composite asthma control and quality of life measures, although potentially useful in research, have limited value in clinical practice because they have a short recall window and do not cover the entire spectrum of asthma control. Telemonitoring of children with asthma cannot replace face-to-face follow-up and monitoring because there is no evidence that it is associated with improved health outcomes.

Differences in spirometry values between U.S. children 6-11 years and adolescents 12-19 years with current asthma, 2007-2010

BACKGROUND

National Asthma Education and Prevention Program (NAEPP) guidelines recommend that periodic spirometry be performed in youth with asthma. NAEPP uses different spirometry criteria to define uncontrolled asthma for children (6-11 years) and adolescents (12+ years).

OBJECTIVE

To describe differences in spirometry between U.S. children and adolescents with current asthma.

METHODS

We examined cross-sectional spirometry data from 453 U.S. youth with current asthma age 6-19 years from the 2007-2010 National Health and Nutrition Examination Surveys. The main outcomes were percentage predicted forced expiratory volume at 1 sec (FEV1%) ≤80 and the ratio of FEV1 to forced vital capacity (FEV1/FVC) ≤0.80. We also examined the prevalence of youth with spirometry values consistent with uncontrolled asthma, using NAEPP age-specific criteria, defined for children aged 6-11 years as FEV1% ≤80 or FEV1/FVC ≤0.80, and for adolescents aged 12-19 years as FEV1% ≤80.

RESULTS

Children 6-11 years and adolescents 12-19 years did not differ in prevalence of FEV1% ≤80 (10.1% vs. 9.0%) or FEV1/FVC ≤0.80 (30.6% vs. 29.8%). However, based on the NAEPP age-specific criteria, 33.0% of children 6-11 years and 9.0% of adolescents 12-19 years had spirometry values consistent with uncontrolled asthma (P < 0.001).

CONCLUSION

Children 6-11 years and adolescents 12-19 years with current asthma did not differ in the percentage with FEV1% ≤80 or FEV1/FVC ≤0.80. However, the percent of children and adolescents with spirometry values consistent with uncontrolled asthma did differ. The difference appears to stem mainly from the different spirometry criteria for the two age groups.

Update on the current methods for the diagnosis and treatment of severe childhood asthma

The level of asthma control is the key outcome towards which asthma management is evaluated. The majority of children with asthma can obtain adequate control of symptoms through avoidance of triggering factors and/or with the help of low to moderate doses of current available medications. However, there is still a group of children with poor symptom control despite intensive treatment. The current review will provide an overview of a standardized approach to characterize this heterogeneous group of severely sick children. Factors that attenuate the effect of the prescribed treatment and make asthma difficult to treat are discussed. In addition, the usefulness of current methods of assessing asthma severity, pulmonary function, allergy and airway inflammation is also described. Finally, an overview of therapeutic options for children with severe asthma is provided.

Monitoring asthma in children

The goal of asthma treatment is to obtain clinical control and reduce future risks to the patient. To reach this goal in children with asthma, ongoing monitoring is essential. While all components of asthma, such as symptoms, lung function, bronchial hyperresponsiveness and inflammation, may exist in various combinations in different individuals, to date there is limited evidence on how to integrate these for optimal monitoring of children with asthma. The aims of this ERS Task Force were to describe the current practise and give an overview of the best available evidence on how to monitor children with asthma. 22 clinical and research experts reviewed the literature. A modified Delphi method and four Task Force meetings were used to reach a consensus. This statement summarises the literature on monitoring children with asthma. Available tools for monitoring children with asthma, such as clinical tools, lung function, bronchial responsiveness and inflammatory markers, are described as are the ways in which they may be used in children with asthma. Management-related issues, comorbidities and environmental factors are summarised. Despite considerable interest in monitoring asthma in children, for many aspects of monitoring asthma in children there is a substantial lack of evidence.

Montelukast in paediatric asthma: where we are now and what still needs to be done?

Leukotriene receptor antagonists were introduced as an entirely new concept in asthma therapy, which indeed they are. However, although an intellectually new concept, they have largely disappointed in clinical practice. A small minority of school age asthmatics may respond better to these medications as against inhaled corticosteroids as prophylactic therapy. In children not responding to low dose inhaled corticosteroids, the best add-on therapy is salmeterol, but a small number respond better to Montelukast. In pre-school wheeze, intermittent Montelukast may be an effective strategy in some children who wheeze just with viral colds, but the clinical trial data are controversial. Pre-schoolers with multiple trigger wheeze are probably best treated with inhaled corticosteroids. What is clear is that clinically, a higher proportion of children are prescribed Montelukast than would be predicted from the lterature to respond to the medication. No biomarker to predict response to Montelukast has reached clinical practice, so N of 1 clinical trials should be performed. It is important not to leave children on Montelukast if there is no convincing response to this treatment.

Sensitivity of different spirometric tests for detecting airway obstruction in childhood asthma

OBJECTIVE

The objective of this study was to compare different measures of airflow obstruction by spirometry in childhood asthma. The objectives were; (a) to compare sensitivity of large airway tests (FEV1 and PEFR) with tests at low lung volumes (small airways) (FEF25-75, FEF50 and FEF75); (b) compare within each group which individual tests are more sensitive.

METHODS

This was a retrospective analysis of 2307 spirometry tests performed during outpatient visits on 821 doctor-diagnosed asthma patients aged 6-18. Tests were deemed acceptable if they were acceptable and repeatable by American Thoracic Society (ATS) criteria.

RESULTS

In mild obstruction, FEV1 detected 6.8% abnormal tests while FEF75 detected 33% (p < 0.0001). In more severe obstruction, the difference was more obvious (FEV1 14.8%; FEF75 71%). Tests at low lung volumes (small airway tests) were also more sensitive than PEFR. Within groups, FEV1 was more sensitive than PEFR in the large airway tests and FEF75 was more sensitive than FEF25-75 and FEF50 among the tests at low lung volumes (small airway tests). The FEV1/FVC ratio correlated more closely with tests at low lung volumes (small airway tests), than with large airway tests.

CONCLUSIONS

(1) Tests at low lung volumes (small airway tests) are more sensitive than large airway tests; (2) Within groups, the FEV1 is better than PEFR and FEF75 is better than FEF25-75 or FEF50.

Spirometry use in children hospitalized with asthma

Asthma is the most common chronic disorder of childhood and continues to be a leading cause of pediatric hospital admission. The National Asthma Education and Prevention Program (NAEPP) recommends that spirometry be obtained for asthma patients upon hospital admission, after bronchodilation during the acute phase of asthma symptoms, and at least one additional time before discharge from the hospital. The objectives of this study were to describe the use of spirometry in children hospitalized with asthma and to determine association of pulmonary function with future exacerbations. A retrospective cohort study design was utilized involving review of medical records of children ≥5 years old admitted with asthma to Cincinnati Children's Hospital Medical Center from September 1, 2009 to March 31, 2011. Hospitalization or emergency department (ED) visits were identified by the ICD-9-CM codes of having either a primary diagnosis of asthma (493) or a respiratory illness (460-496) plus a secondary diagnosis of asthma. Asthma re-exacerbation was defined as either having an ED visit or hospitalization for asthma that occurred within 3 months after the index hospitalization. All spirometries were performed in a pediatric pulmonary function laboratory. Among 1,037 admissions included in this study, 89 (8.6%) had spirometry that was recommended by a consulting asthma specialist and usually performed on the day of discharge. Spirometries for forty-five of these patients (54.9%) met all acceptability and repeatability criteria of the American Thoracic Society. Patients who performed acceptable spirometry were significantly older (12.4 ± 3.8 vs. 10.7 ± 3.0 years; P = 0.041). The average forced expiratory volume in the first second (FEV1 ) was 84.4 ± 19.7% predicted; forced vital capacity (FVC) was 98.1 ± 16.0% predicted; FEV1 /FVC was 74.6 ± 9.6%; forced expiratory flow at 25-75% (FEF25-75 ) was 61.2 ± 30.1% predicted. Ten patients (22%) who performed spirometry developed a re-exacerbation. Patients with versus without re-exacerbation had significantly lower FEV1 /FVC (P = 0.027) and FEF25-75 (P = 0.031). Nevertheless, separate logistic regression models found that FEV1 /FVC and FEF25-75 were not associated with re-exacerbation when adjusted for age and length-of-stay. We found that few children admitted with asthma had spirometry as recommended in the NAEPP guidelines unless recommended by specialists and both lower lung function (FEV1 /FVC and FEF25-75 ) and history of more frequent and more recent prior health-care utilization for asthma were associated with repeat asthma exacerbation. However, the value of performing spirometry on asthmatic children prior to hospital discharge remains unclear and will require prospective study.

Genetic predictors associated with improvement of asthma symptoms in response to inhaled corticosteroids

BACKGROUND

To date, genome-wide association studies (GWASs) of inhaled corticosteroid (ICS) response in asthmatic patients have focused primarily on lung function and exacerbations.

OBJECTIVE

We hypothesized that GWAS analysis could identify novel genetic markers predicting a symptomatic response to ICSs.

METHODS

We analyzed differences in asthma symptoms in response to ICSs in 124 white children from the Childhood Asthma Management Program (CAMP) trial using scores from diary cards. Of the 440,862 single nucleotide polymorphisms (SNPs) analyzed, the top 100 ranked SNPs were pursued for replication initially in subjects from the pediatric Childhood Asthma Research and Education trials (77 white children) and then in subjects from the adult Asthma Clinical Research Network (110 white adults) and Leukotriene Modifier or Corticosteroid or Corticosteroid-Salmeterol trials (110 white adults).

RESULTS

The lowest P value for GWAS analysis in the CAMP trial was 8.94 × 10(-8) (rs2388639). Of the 60 SNPs available in the Childhood Asthma Research and Education Network trials, rs1558726 (combined P = 1.02 × 10(-5)), rs2388639 (combined P = 8.56 × 10(-9)), and rs10044254 (combined P = 9.16 × 10(-8)) independently replicated. However, these 3 SNPs were not additionally replicated in the adult asthmatic patients of the remaining trials. rs10044254 lies in the intronic region of F-box and leucine-rich repeat protein 7 (FBXL7) and is associated with decreased expression in immortalized B cells derived from CAMP participants.

CONCLUSIONS

We have identified a novel SNP, rs10044254, associated with both decreased expression of FBXL7 and improved symptomatic response to ICSs in 2 independent pediatric cohorts. Our results suggest that there might be a specific genetic mechanism regulating symptomatic response to ICSs in children that does not carry over to adults.

Macrolides for the long-term management of asthma--a meta-analysis of randomized clinical trials

BACKGROUND

Macrolide antibiotics, which have anti-inflammatory and immune modulatory effects, have been studied as adjuncts for the management of asthma. However, results have been contradictory and trials underpowered. We therefore sought to conduct a meta-analysis of randomized controlled trials (RCT).

METHODS

All RCT of prolonged macrolides (3+ weeks) for asthma treatment, published up to January 2013 in MEDLINE, Scopus, CINAHL, Highwire, and The Cochrane Collaboration Library, were included. Fixed- or random-effects models were used to calculate pooled weighted or standard mean differences (WMD or SMD, respectively).

RESULTS

A total of 12 studies were included for analysis. The pooled effect of macrolides on FEV1 (eight trials, 381 subjects) was not significant (SMD 0.05, 95% CI -0.14-0.25), but there was a significant increase in peak expiratory flow (four trials, 419 subjects; WMD 6.7, 95% CI 1.35-12.06). Pooled analysis also showed significant improvements in symptom scores (eight studies, 478 subjects; WMD -0.46, 95% CI -0.60 to -0.32), quality of life (five trials, 346 subjects; WMD 0.18, 95% CI 0.001-0.37), and airway hyper-reactivity (two trials, 131 subjects; SMD 1.99, 95% CI 0.46-3.52). Post hoc evaluation showed limited statistical power to detect significant differences in FEV1.

CONCLUSIONS

Macrolide administration for asthma for three or more weeks was not associated with improvement in FEV1, but produced significant improvements in peak expiratory flow, symptoms, quality of life, and airway hyper-reactivity. Macrolides may therefore be beneficial as adjunct asthma therapy. Future trials, focusing on long-term safety and effectiveness, should use standardized outcomes and procedures.

The clinician's guide on monitoring children with asthma

Based on a review of the evidence on the usefulness of monitoring disease outcome parameters in childhood asthma and the author's 20-yr clinical experience in managing childhood asthma, this article provides the clinician with up-to-date recommendations on how to monitor childhood asthma in everyday clinical practice. Monitoring should be focused on patient-centered outcomes, such as exacerbations and impact on sports and play. Composite asthma control measures, although reasonably validated, do not take exacerbations into account and have a short recall window, limiting their usefulness as a routine monitoring tool in clinical practice. Lung function, airways hyperresponsiveness, exhaled nitric oxide, and inflammatory markers in sputum are surrogate end points, of little if any interest to patients. There is no evidence to support their use as a monitoring tool in clinical practice; office spirometry may be used as additional information. Rather than monitoring surrogate end points, clinicians should focus on showing a genuine interest in the impact of asthma on children's daily lives, and building and maintaining a partnership by monitoring those characteristics of asthma which have the biggest impact on children (exacerbations and limitations in sports and play), and adjusting treatment accordingly.

Use of impulse oscillometry system in assessment of asthma severity for preschool children

OBJECTIVE

The National Asthma Education and Prevention Program/Expert Panel Report (NAEPP/EPR)-3 Guidelines for asthma treatment categorize asthma severity based on impairment and risks and on medications administered. The objective of this study was to determine whether impulse oscillometry system (IOS) measures in preschool children are consistent with asthma severity as defined by NAEPP/EPR-3 Guidelines.

METHODS

Asthma severity of the 162 subjects (aged 2-5 years) was classified by impairment and risks for exacerbations requiring oral systemic corticosteroids, by medication usage, and by combination classification (higher severity of impairment and risks or medication usage). An experienced pediatrician determined the appropriate medications for each child and parents completed structured questionnaires regarding day and night symptoms and interference with normal activity over the preceding 4 weeks. All children were tested by IOS.

RESULTS

The mean age was 3.7 ± 0.9 years and 91 (56%) of the total patients were males. When asthma severity was based on (1) impairment and risks and (2) medication usage, asthma was "intermittent" in 17.9% and 11.1% of the total patients, "mild persistent" in 42.0% and 50.6% of total patients, and "moderate-severe persistent" in 40.1% and 38.3% of total patients, respectively. The agreement between severity based on impairment and risks and medication usage was not significant. Xrs(5) z-scores differed between intermittent asthma and mild/moderate-severe persistent asthma, as determined by medication usage and combination classification, but not by impairment and risks. As asthma severity (assessed by medication usage) increased, the duration of asthma increased.

CONCLUSIONS

Xrs(5) can be used to discriminate intermittent and persistent asthma in preschool children. Further studies with larger sample sizes are warranted to confirm this finding and to determine the underlying mechanism.

Phenotypes of refractory/severe asthma

The acid test of phenotyping is that it leads either to a clinically useful or mechanistically important insight. Phenotypes may change over time, but the exact definition of a phenotype shift is unclear. Methods of phenotyping are either investigator driven, in which a priori prejudices are applied to the data, or (semi) objective, in which mathematical techniques or systems biology approaches are applied to the dataset. However, the composition of the dataset is driven by investigator prejudice. Phenotyping is likely most useful in severe asthma, because mild and moderate asthma responds to simple treatments, and no great subtlety is required. Our non-evidence based approach is to define the subpopulation of genuine severe, therapy-resistant asthmatics from the generality of problematic severe asthma. We then investigate them invasively with bronchoscopy and a steroid trial using intramuscular triamcinolone to determine the nature of any inflammatory process; whether inflammation and symptoms are concordant or discordant; whether the inflammatory process is steroid resistant or sensitive; and whether the child has persistent airflow limitation. Other possibly relevant phenotypes include the child with severe exacerbations; brittle asthma; and severe asthma with fungal sensitization. Severe, therapy resistant asthma is a disparate disease, and only international uniform approaches, carefully characterising the children as a prelude to focussed clinical trials will allow progress to be made, and vindicate (or otherwise) our suggested approach.

Genetic biomarkers of health-related quality of life in pediatric asthma

OBJECTIVES

To determine the relationship between single nucleotide polymorphisms in candidate genes associated with multiple asthma phenotypes and health-related quality of life (HRQOL).

STUDY DESIGN

A cross-sectional study was conducted at a pediatric hospital in 275 school-aged children diagnosed with asthma and their caregivers. Genomic DNA was obtained from children, and caregivers completed a measure of their child's HRQOL. Analysis of variance was used to investigate the association between single nucleotide polymorphisms and HRQOL.

RESULTS

Children homozygous for the major variant at IL-4RA rs 1805010 had significantly better HRQOL than their counterparts. Significant associations with pulmonary function were not observed.

CONCLUSIONS

Genes associated with asthma phenotype can be associated with HRQOL at least partly independent of pulmonary function.

Monitoring asthma control in children with allergies by soft computing of lung function and exhaled nitric oxide

BACKGROUND

Asthma control is emphasized by new guidelines but remains poor in many children. Evaluation of control relies on subjective patient recall and may be overestimated by health-care professionals. This study assessed the value of spirometry and fractional exhaled nitric oxide (FeNO) measurements, used alone or in combination, in models developed by a machine learning approach in the objective classification of asthma control according to Global Initiative for Asthma guidelines and tested the model in a second group of children with asthma.

METHODS

Fifty-three children with persistent atopic asthma underwent two to six evaluations of asthma control, including spirometry and FeNO. Soft computing evaluation was performed by means of artificial neural networks and principal component analysis. The model was then tested in a cross-sectional study in an additional 77 children with allergic asthma.

RESULTS

The machine learning method was not able to distinguish different levels of control using either spirometry or FeNO values alone. However, their use in combination modeled by soft computing was able to discriminate levels of asthma control. In particular, the model is able to recognize all children with uncontrolled asthma and correctly identify 99.0% of children with totally controlled asthma. In the cross-sectional study, the model prospectively identified correctly all the uncontrolled children and 79.6% of the controlled children.

CONCLUSIONS

Soft computing analysis of spirometry and FeNO allows objective categorization of asthma control status.

Lung function measurement in the assessment of childhood asthma: recent important developments

PURPOSE OF REVIEW

To present three clinically important developments related to the utilization of pulmonary function to objectively assess the asthmatic child.

RECENT FINDINGS

The new asthma guidelines (2007) have added the forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) ratio to the FEV1 as spirometric criteria for classifying asthma. Although a better indicator of airway obstruction, it has not clearly been shown to correlate with clinical criteria. The normal cut point for the ratio used in the guidelines of 85% for children may be too high, and compared to the lower limits of normal of 80%, could result in unnecessary treatment in some children. The bronchodilator response (BDR) phenotype reflects airway lability and has been associated with biomarkers of inflammation and responsiveness to inhaled corticosteroids as well as predicting long-term outcomes. Several studies have shown improved spirometric techniques in preschoolers as well as defining normal values in this age group. Impulse oscillometry (IOS), which is less demanding than spirometry, has been shown to identify asthmatic preschoolers in some cases better than spirometry and possibly identifying obstruction in the peripheral airways. It may also be a more useful test than spirometry in evaluating long-term drug studies.

SUMMARY

In addition to the FEV1/FVC ratio to detect airway obstruction, the BDR phenotype would appear to give important additional information regarding airway lability and inflammation, and should be included as routine spirometry. IOS is a promising test to identify asthmatic preschoolers, but more studies are needed to determine exactly what it measures and what constitutes normal values.

Management of severe asthma in children

Children who are referred to specialist care with asthma that does not respond to treatment (problematic severe asthma) are a heterogeneous group, with substantial morbidity. The evidence base for management is sparse, and is mostly based on data from studies in children with mild and moderate asthma and on extrapolation of data from studies in adults with severe asthma. In many children with severe asthma, the diagnosis is wrong or adherence to treatment is poor. The first step is a detailed diagnostic assessment to exclude an alternative diagnosis ("not asthma at all"), followed by a multidisciplinary approach to exclude comorbidities ("asthma plus") and to assess whether the child has difficult asthma (improves when the basic management needs, such as adherence and inhaler technique, are corrected) or true, therapy-resistant asthma (still symptomatic even when the basic management needs are resolved). In particular, environmental causes of secondary steroid resistance should be identified. An individualised treatment plan should be devised depending on the clinical and pathophysiological characterisation. Licensed therapeutic approaches include high-dose inhaled steroids, the Symbicort maintenance and reliever (SMART) regimen (with budesonide and formoterol fumarate), and anti-IgE therapy. Unlicensed treatments include methotrexate, azathioprine, ciclosporin, and subcutaneous terbutaline infusions. Paediatric data are needed on cytokine-specific monoclonal antibody therapies and bronchial thermoplasty. However, despite the interest in innovative approaches, getting the basics right in children with apparently severe asthma will remain the foundation of management for the foreseeable future.