Peak Expiratory Flow Variability Research Articles

The relationship between changes in peak expiratory flow and asthma exacerbations in asthmatic children

BackgroundAsthma is one of the most common chronic airway diseases in children. Preventing asthma exacerbation is one of the objectives of all asthma action plans. In patients with poor perception, it is difficult to identify acute asthma exacerbations by clinical asthma score, asthma control test or asthma control questionnaire. The aim of this study is to analyze whether children with asthma have changes in peak expiratory flow(PEF)before an acute asthma exacerbation and to evaluate the relationship between PEF and asthma exacerbation.MethodsBasic information (including sex, age, atopy, etc.) and clinical information of asthmatic children who registered in the Electronic China Children’s Asthma Action Plan (e-CCAAP) from 1 September 2017 to 31 August 2021 were collected. Subjects with 14 consecutive days of PEF measurements were eligible. Subjects in this study were divided into an exacerbation group and a control group. We analyzed the relationship between changes in PEF% pred and the presence of asthma symptoms.ResultA total of 194 children with asthma who met the inclusion criteria were included, including 144 males (74.2%) and 50 females (25.8%), with a male-to-female ratio of 2.88:1. The mean age of the subjects was 9.51 ± 2.5 years. There were no significant differences in sex, age, allergy history or baseline PEF between the two groups. In children with and without a history of allergy, there was no significant difference between the variation in PEF at 14 days. Patients who only had a reduced in PEF but no symptoms of asthma exacerbation had the greatest reduction in PEF compared to the other groups. The most common cause of acute exacerbations of asthma is upper respiratory tract infection. Among the causes of acute exacerbations of asthma, the variation in PEF caused by air pollution was significantly higher than that of other causes (P < 0.05). In acute exacerbations, the decrease in PEF was significantly greater in the exacerbation group than in the control group. In children with asthma symptoms, there was a decrease in PEF approximately 1.34 days before the onset of symptoms.ConclusionChildren with asthma show a decrease in PEF 1.34 days before the onset of asthma symptoms. We recommend that asthmatic children who show a decrease in PEF should step-up asthma therapy. The most common cause of acute exacerbations of asthma was upper respiratory tract infections, and the variation in PEF caused by air pollution was significantly higher than that caused by other factors.

What is the Best Way to Diagnose Possible Asthma Patients with Negative Bronchodilator Reversibility Tests?

The best method and strategy for the diagnosis of asthma remains unclear, especially in patients with negative bronchodilator reversibility test (BDRT). In our study, we aimed to investigate the diagnostic yield of peak expiratory flow (PEF) variability for this patient group. A total of 50 patients with suspected asthma, all with negative BDR test, were included in the study. Demographic information and symptoms were recorded and PEF variability was monitored for 2 weeks. Metacolinbronchial provocation test (mBPT) was performed. Asthma was diagnosed when PEF variability ≥20% and/or positive mBPT was observed. 30 of 50 patients were diagnosed with asthma. After 1 month, 17 patients were evaluated for treatment outcomes. The sensitivity and specificity of PEF variability for different cut-off values (≥20%, >15% and >10%) were 61.5-83.3, 88.5-62.5 and 100-16.7, respectively. One of the most important findings of our study was the absence of variable airflow limitation or airway hyper reactivity in 39% patients with a previous diagnosis of asthma. Multiple logistic regression analysis revealed that a low baseline FEF25-75 value was an independent predictive factor for the diagnosis of asthma (p= 0.05). The most efficient diagnostic test for asthma is still unclear due to many factors. Our study is one of the few studies on this subject. Although current diagnostic recommendations generally recommend a PEF variability of 10% for the diagnosis of asthma, this threshold may not be appropriate for the BDR-negative patient group. Our results suggest using a threshold value of <15% for PEF variability when excluding asthma and ≥20% when confirming the diagnosis of asthma in patients with clinically suspected but unproven reversibility. Furthermore, FEF25-75 is considered to be an important diagnostic parameter that should be included in diagnostic recommendations for asthma.

Brittle Asthma: Still on Board?

(1) Background: "Brittle Asthma" was considered an asthma clinical phenotype and deemed to be life-threatening in the early 2000s; then, this definition disappeared. The purpose of this review is to examine what has historically been referred to as this term and see whether it may be applied to modern clinical practice, thus acquiring fresh relevance and meaning. (2) Methods: A non-systematic search of the literature was conducted using both MeSH and free-text phrases. No limitations on the research design or type of publication were applied. (3) Results: Reliable data regarding "Brittle Asthma" are lacking due to the paucity of current data and the few studies available. After a few years of reworking, it was divided into two sub-classes: one characterized by a wide PEF variability despite high-dose therapy and the other by sudden acute attacks in otherwise apparently normal airway functions or well-controlled asthma. Their characteristics were hardly defined because of their low prevalence. Data regarding risk factors, atopy, mechanisms, and treatments were analyzed. (4) Conclusions: Over time, different terminology has been introduced to define asthma severity and control. It would be worth investigating whether the term "Brittle Asthma" previously used may be helpful to find new hints to stratify patients and improve disease management.

Short-term exposure to ozone and asthma exacerbation in adults: A longitudinal study in China.

The relationships between short-term ozone exposure and the acute exacerbations of asthma in adults have not been fully studied. Existing studies commonly ignored the effects of ozone on mild or early asthma exacerbations. To investigate the associations between short-term ozone exposure and asthma exacerbations in Chinese adults. We administered health management for adult asthma patients through the Respiratory Home Platform and required them to monitor their lung function every morning and evening by themselves. Finally, a total of 4,467 patients in 18 Chinese cities were included in the current analyses, with 79,217 pairs of lung function records. The maximum daily 8-h average ozone concentrations were collected from fixed-site air quality monitoring stations. We calculated diurnal peak expiratory flow (PEF) variation using morning and evening measurements of PEF and then defined different severity of asthma exacerbations with diurnal PEF variations >10, 15, and 20%, respectively. A binomial distributed generalized additive mixture model combined with distribution non-linear models was applied to examine the association of ozone with asthma exacerbations. We further conducted stratified analyses by sex, age, season of lung function tests, and region. We found that short-term ozone exposure was independently associated with an elevated risk of asthma exacerbations defined by lung function and the effects could last for about 2 days. At lag 0-2 days, each 10 μg/m3 increment in ozone concentration was associated with odds ratios of 1.010 [95% confidence interval (CI): 1.003, 1.017], 1.014 (95% CI: 1.005, 1.023), and 1.017 (95% CI: 1.006, 1.028) for asthma exacerbations that were defined by diurnal PEF variation over 10, 15, and 20%, respectively. The associations remained significant after adjusting for other pollutants, and became unstable when using 24-h average ozone concentration. We also found that the associations were relatively stronger in males, those aged 45 years and older, and in the warm season. Our results suggest that short-term ozone exposure can increase the risk of asthma exacerbations, even in the early stage of exacerbation. Male and older asthma patients may be more vulnerable to ozone air pollution, especially in the warm season.

Laboratory Experiments on the Influence of the Wave Spectrum Enhancement Factor on a Rubble Mound Breakwater

This paper experimentally explored the influence of the wave spectrum shape variation on breakwater design. The energy spectrum function generally considered for the design of coastal structures is the JONSWAP spectrum. The laboratory results were therefore used to assess the impact of changing the spectrum shape parameter (PEF). We analysed armour stability and wave overtopping in a wave flume with a geometric similarity ratio of 1:30. The experimental results showed that the PEF has maximum influence on overtopping and wave pressures on the crown wall. For a PEF value of 3.3, overtopping was much higher (30% to 100% higher) than with a PEF of 1. Pressure on the crown wall was 20% higher with a PEF of 3.3 in comparison with that for a PEF equal to 1. The stability of the breakwater’s block armour is less sensitive to the PEF variation.

The positive association between various demographic characteristics and peak expiratory flow in employees of Zanjan university of medical sciences

Introduction: Peak expiratory flow (PEF) is a reliable criterion for assessing respiratory capacity, and has a wide range of clinical application as a marker of asthma control. However, its wide variability undermines its efficacy. Objectives: This study was designed to evaluate PEF changes in staff of Zanjan University of Medical Sciences. Patients and Methods: Four hundred employees of this university participated in this cross-sectional study. Their PEF values were measured using peak flow meter in the morning at 8 AM and in the afternoon at 2 PM by three times for each individual, and then the highest amount of PEF was recorded about for measurement. Results: Obviously, PEF values were higher in the afternoon (43865 L/min) in comparison to the morning measurements (404.60 L/min) by paired t test (P&lt;0.001). In addition, mean of PEF in the males was higher than the females in the morning (469.77 L/min, versus 355.94 L/min; independent t test, P&lt;0.001), and also PEF mean of the morning and afternoon was higher in the males than females (404.6 L/min, versus 338.65 L/min, independent t test, P&lt;0.001). Additionally, the variability level in the males and females was 8.39±6 and 8.47±4 L/min, respectively. There was a high correlation between the level of PEF variability and height (5.1). Meanwhile, a moderate correlation between PEF level and body mass index (BMI) was detected (1.47). There was not any correlation between the level of PEF and age. Conclusion: Based on our findings, PEF inter-individual variability depends on age, gender height, and BMI however, it is worthwhile that this PEF inter-individual variability to be measured just until 4 PM. All these variables were obtained under the range of 20%; however, relying on references, the variability of 20% is considered as normal.

Telehome Monitoring of Symptoms and Lung Function in Children with Asthma.

Background: The ability to perceive bronchial obstruction is variable in asthma. This is one of the main causes of inaccurate asthma control assessment, on which therapeutic strategies are based. Objective: Primary: To evaluate the ability of physicians to characterize the bronchial obstruction perception profile in asthmatic children using a clinical and spiro-metric telemonitoring device. Secondary: To evaluate its impact on asthma management (control, treatment, respiratory function variability) and the acceptability of this telemonitoring system. Methods: 26 asthmatic children aged 6–18 years equipped with a portable spirometer and a smartphone application were home-monitored remotely for 3 months. Clinical and spiro-metric data were automatically transmitted to a secure internet platform. By analyzing these data, three physicians blindly and independently classified the patients according to their perception profile. The impact of telemonitoring on the quantitative data was assessed at the beginning (T0) and end (T3 months) of telemonitoring, using matched statistical tests. Results: Patients could initially be classified according to their perception profile, with a concordance between the three observers of 64% (kappa coefficient: 0.55, 95%CI [0.39; 0.71]). After discussion among the observers, consensus was reached for all patients but one. There was a significant >40% decrease in FEV1 and PEF variability, with good acceptance of the device. Conclusions: Clinical and spiro-metric tele-home monitoring is applicable and can help define the perception profile of bronchial obstruction in asthmatic children. The device was generally well accepted.

European Respiratory Society Guidelines for the Diagnosis of Asthma in Adults.

Although asthma is very common affecting 5-10% of the population, the diagnosis of asthma in adults remains a challenge in the real world that results in both over- and under-diagnosis. A task force (TF) was set up by the European Respiratory Society to systematically review the literature on the diagnostic accuracy of tests used to diagnose asthma in adult patients and provide recommendation for clinical practice.The TF defined eight PICO (Population, Index, Comparator, and Outcome) questions that were assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach, The TF utilised the outcomes to develop an evidenced-based diagnostic algorithm, with recommendations for a pragmatic guideline for everyday practice that was directed by real-life patient experiences.The TF support the initial use of spirometry followed, and if airway obstruction is present, by bronchodilator reversibility testing. If initial spirometry fails to show obstruction, further tests should be performed in the following order: FeNO, PEF variability or in secondary care, bronchial challenge. We present the thresholds for each test that are compatible with a diagnosis of asthma in the presence of current symptoms.The TF reinforce the priority to undertake spirometry and recognise the value of measuring blood eosinophils and serum IgE to phenotype the patient. Measuring gas trapping by body plethysmography in patients with preserved FEV1/FVC ratio deserves further attention. The TF draw attention on the difficulty of making a correct diagnosis in patients already receiving inhaled corticosteroids, the comorbidities that may obscure the diagnosis, the importance of phenotyping, and the necessity to consider the patient experience in the diagnostic process.

Predictive characteristics to discriminate the longitudinal outcomes of childhood asthma: a retrospective program-based study.

Childhood asthma is an inflammatory disease with heterogeneous outcomes. We sought to determine the impact of total IgE, blood eosinophil, allergen sensitization, and inhaled corticosteroid (ICS) on longitudinal outcomes and to identify characteristics for discriminating different outcomes. We conducted a retrospective study in 383 childhood asthma patients and another 313 patients with blood eosinophil data only receiving regular program-based visits from September 1, 2004, to December 31, 2018. Peak expiratory flow (PEF) variability, PEF predicted %, asthma severity, and asthma control at each visit were assessed as clinical outcomes. Our data show that the percentage of blood eosinophils was significantly associated with increased asthma severity (OR: 1.043, 95% CI: 1.002-1.086, P = 0.0392). Mold sensitization was significantly associated with asthma severity (OR: 2.2485, 95% CI: 1.3253-3.8150, P = 0.0027). Characteristics including sensitization status plus ICS dosage had the best area under the receiver operating characteristic curve (AUC) value for predicting longitudinal PEF predicted % (0.6609), PEF variability (0.6885), asthma severity (0.5918), and asthma control (0.6441), respectively. We showed that the risk for adverse clinical outcomes at follow-up differed between serum IgE, blood eosinophil, and allergen sensitization identified at baseline. Sensitization and ICS dosage were predictive characteristics of long-term clinical outcomes. The unique aspects of the study are its longitudinal assessment of patients receiving guideline-based asthma management program to help characterize the stability of the clinical outcomes over time. Characteristics including allergen sensitization and ICS dosage demonstrated an improved capability for distinguishing between better and worse clinical outcomes. Through longitudinal serial assessment, this study indicates the risk for adverse clinical outcomes differed between children with serum IgE/blood eosinophil/allergen sensitization characterized at baseline.

Associations between pulmonary function and cognitive decline in the middle-aged and older adults: evidence from the China Health and Retirement Longitudinal Study.

Studies observing the relationship between pulmonary function and the risk of cognitive impairment in middle-aged and older adults was increasing, but the results were inconsistent. To date, evidence from longitudinal data is scarce and further research is urgently needed. We used data from the China Health and Retirement Longitudinal Study. Participants were enrolled in 2011/2013 and followed up in 2013, 2015 and 2018. Pulmonary function was assessed via peak expiratory flow (PEF). Cognitive function, measured by episodic memory and mental status, was assessed through a face-to-face interview in each survey. A total of 8,274 participants (52.86% males; mean age, 56.44 years) were included. The scores of global cognition (12.46 versus 11.51, P < 0.001) of men were significantly higher than women at baseline, with a total of 5096 participants (61.59%) declining during the follow-up. Higher baseline PEF was associated with lower absolute decline in global cognition (OR per 1-SD difference 0.921; P = 0.031) and mental status (OR per 1-SD difference 0.9889; P = 0.002) during follow-up in men, and significant associations between higher baseline PEF and a lower absolute decline in the episodic memory were both found in men (OR per 1-SD difference 0.907; P = 0.006) and women (OR per 1-SD difference 0.915; P = 0.022). Second analysis showed that the significant associations between positive PEF variation and a lower rate of 4-year decline in global cognition, mental status and episodic memory were all only found in men. In subgroup analyses, higher PEF at baseline was significantly associated with a lower absolute decline of global cognition among male individuals >60 years. Significant associations between higher PEF at baseline and lower absolute decline in global cognition and episodic memory during follow-up were only found in never-smokers, while higher PEF was related to lower absolute decline in mental status among non-smoking and smoking males. Pulmonary function correlates with cognitive functions in middle-aged and older people, especially males. Additional studies characterizing early and long-term PEF changes are needed.

Cold temperature and sudden temperature drop as novel risk factors of asthma exacerbation: a longitudinal study in 18 Chinese cities

BackgroundFew studies have explored the role of ambient temperature in asthma exacerbation. ObjectiveWe aimed to explore the association of temperature with diurnal peak expiratory flow (PEF) variation and asthma exacerbation. MethodWe developed a longitudinal study among asthmatic adults in 18 Chinese cities. Subjects recorded PEF in dynamic pulmonary function monitoring from 2017 to 2020. Linear mixed-effect model and generalized additive model with distributed non-linear models were used to assess the effect of temperature and temperature change between neighboring days (TCN) on diurnal PEF variation and the risk of asthma exacerbation. ResultWe evaluated a total of 79,217 daily PEF monitoring records from 4467 adult asthmatic patients. There were significant increase of diurnal PEF variation and higher risk of asthma exacerbation with cold and sudden temperature drop. Compared with the referent temperature (99th percentile, 32 °C), exposure to moderate cold (25th percentile, 3 °C) and extreme cold (2.5th percentile, −7 °C) was associated with elevations of 1.28% and 1.16% in diurnal PEF variation over lag 0–2 days, respectively. The odds ratios of asthma exacerbation (determined by diurnal PEF variation >20%) at the two temperature cutoffs were 1.68 and 1.73. A sudden temperature drop (2.5th percentile of TCN, −5 °C) was associated with 1.13% elevation in diurnal PEF variation, and with increased risk of asthma exacerbation (odd ratio = 1.50) over lag 0–4 days. ConclusionThis large multicenter study provided the first-hand empirical evidence that cold temperature and a temperature drop may increase the risk of asthma exacerbation.

Preliminary clinical observation of omalizumab therapy for moderate to severe asthma

Objective: To observe the effectiveness, safety and management of omalizumab therapy for moderate to severe asthma in real-world clinical practice in China. Methods: This retrospective analysis involved 79 patients with moderate to severe asthma who received omalizumab therapy for at least 4 months in the First Affiliated Hospital of Guangzhou Medical University from March 2018 to April 2020. All participants were between 14 to 76 years old(median 50 years),including 30 males and 49 females. Data regarding the patients' clinical manifestations, eosinophil count, fractional exhaled nitric oxide (FeNO), lung function, oral corticosteroid dosage, and adverse reactions were collected before and after treatment. Paired t-test or non-parametric paired Wilcoxon analysis was used for pairwise comparison, Mann Whitney analysis for inter-group comparison, and Chi square test or Fisher test for inter-group comparison of count data. Results: The following changes were noted after 4 months of omalizumab thearpy. The patients' Asthma Control Test (ACT) scores increased from 17.0 (13.0-19.0) to 20.0 (18.0-24.0) points (P<0.001). The frequency of acute exacerbations(AE) decreased from 1.0 (0-1.0) to 0 (0-1.0) episodes every 4 months (P<0.001). The variation rate of the peak expiratory flow (PEF) decreased from 16.5 (13.8-27.3)% to 10.4 (6.0-16.2)% (P<0.001). The percent predicted value of PEF (PEFpred%) increased from 71.7 (51.4-91.6)% to 87.5 (65.2-105.5)% (P<0.001). The percent predicted value of the forced expiratory volume in 1 second(FEV1%pred) increased from 73.6 (53.9-90.8)% to 80.6 (68.7-91.8)% (P=0.007). The maintenance dose of oral corticosteroids (OCS) decreased from 12.0 (10.0-20.0) to 5.0 (0-17.5) mg/day (P=0.001). After 4 months of treatment, the response rate of the 79 patients with asthma was 74.7%. The response rate of patients with allergic asthma (77.3%) was higher than that of patients with non-allergic asthma (25.0%) (P=0.019). Among 5 patients who completed 1 year of treatment, the ACT score, frequency of AE, PEFpred%, variation rate of PEF and OCS maintenance dose were still improved after 1 year of treatment. Adverse reactions occurred in 3 patients (3.8%), for a total of 3 (0.6%) times. Stratified analysis showed that after 4 months of treatment, the improvement in the ACT score and the decrease in the PEF variation rate among patients who reached the recommended treatment dose (full dose) [3.0 (1.0-8.0) points, 6.5 (3.5-15.8) %] were significantly higher than those among patients who did not reach the recommended treatment dose (insufficient dose) [1.0 (-0.3-3.0) points, 2.9 (1.5-5.0) %] (P<0.05). Additionally, the treatment response rate in patients with a sufficient dose (80.0%) was higher than that in patients with an insufficient dose (50.0%) (P=0.019).The main factors associated with stopping treatment within 1 year despite a response to omalizumab was economic burden (70.3%), followed by satisfactory improvement by self-evaluation (21.9%) and less improvement in symptoms than expected (7.8%). Conclusion: Omalizumab was an effective treatment for moderate to severe allergic asthma with few adverse effects. The response rate was higher when the recommended injection dose was achieved. Financial difficulty was the main reason for stopping treatment within 1 year despite a good therapeutic response.

Lung Function Variability in Children and Adolescents With and Without Asthma (LUV Study): Protocol for a Prospective, Nonrandomized, Clinical Trial.

BackgroundVariability analysis of peak expiratory flow (PEF) and forced expiratory volume at 1 second (FEV1) has been used in research to predict exacerbations in adults with asthma. However, there is a paucity of data regarding PEF and FEV1 variability in healthy children and adolescents and those with asthma.ObjectiveThe objective of this study is the assessment of PEF and FEV1 variability in (1) healthy children and adolescents, to define the normal daily fluctuation of PEF and FEV1 and the parameters that may influence it, and (2) children and adolescents with asthma, to explore the differences from healthy subjects and reveal any specific variability changes prior to exacerbation.MethodsThe study will include 100 healthy children and adolescents aged 6-18 years (assessment of normal PEF and FEV1 variability) and 100 children and adolescents of the same age with diagnosed asthma (assessment of PEF and FEV1 variability in subjects with asthma). PEF and FEV1 measurements will be performed using an ultraportable spirometer (Spirobank Smart; MIR Medical International Research) capable of smartphone connection. Measurements will be performed twice a day between 7 AM and 9 AM and between 7 PM and 9 PM and will be dispatched via email to a central database for a period of 3 months. PEF and FEV1 variability will be assessed by detrended fluctuation and sample entropy analysis, aiming to define the normal pattern (healthy controls) and to detect and quantify any deviations among individuals with asthma. The anticipated duration of the study is 24 months.ResultsThe study is funded by the “C. Caratheodory” Programme of the University of Patras, Greece (PN 47014/24.9.2018). It was approved by the Ethics Committee (decision 218/19-03-2019) and the Scientific Board (decision 329/02-04-2019) of the University Hospital of Patras, Greece. Patient recruitment started in January 2020, and as of June 2020, 100 healthy children have been enrolled (74 of them have completed the measurements). The anticipated duration of the study is 24 months. The first part of the study (assessment of lung function variability in healthy children and adolescents) will be completed in August 2020, and the results will be available for publication by October 2020.ConclusionsHealthy children and adolescents may present normal short- and long-term fluctuations in lung function; the pattern of this variability may be influenced by age, sex, and environmental conditions. Significant lung function variability may also be present in children and adolescents with asthma, but the patterns may differ from those observed in healthy children and adolescents. Such data would improve our understanding regarding the chronobiology of asthma and permit the development of integrated tools for assessing the level of control and risk of future exacerbations.Trial RegistrationClinicalTrials.gov NCT04163146; https://clinicaltrials.gov/ct2/show/NCT04163146International Registered Report Identifier (IRRID)DERR1-10.2196/20350

Therapeutic Response of Patients with Chest Tightness Variant Asthma: A One-Year Multicenter, Prospective Real-Life Study

Background: Although asthmatic patients with chest tightness as their only presenting symptom (chest tightness variant asthma, CTVA) have clinical characteristics of eosinophilic airway inflammation similar to those of classic asthma (CA), the response of CTVA to treatment regimens used for CA is unclear. Methods: To explore the clinical course and response of 96 CTVA patients to standard asthma treatments with inhaled corticosteroids with long-acting beta-agonists in a 52-week multicenter, prospective, real-life study. Findings: After 52 weeks of treatment with therapy regimens used for CA, the 5-point Asthma Control Questionnaire (ACQ-5) scores decreased markedly from 1·34±0·88(before treatment; V0) to 0·97±0·70 (4 weeks, V1), 0·83±0·72 (13 weeks, V2), 0·73±0·76 (26 weeks, V3), and 0·76±0·79(52 weeks, V4) ( P <0·01), while the Asthma Quality of Life Questionnaire (AQLQ) scores increased from 5·76±0·76 (V0) to 6·24±0·60(V3) and 6·14±0·60(V4) ( P <0·01). The Self-rating Anxiety Scale(SAS) score improved as evidenced by a decrease from 41·44±10·24 (V0) to 37·61±11·41 (V2) and 37·67±8·07 (V4) ( P <0·01). Diurnal variation in peak expiratory flow (PEF) and the bronchial provocation test were improved at one year. However, forced expiratory volume (FEV1) andnitric oxide levels in exhaled breath (FeNO) showed no improvement. Interpretation CTVA patients showed a good clinical response to anti-asthma treatments, and the treatment effects may be related to theseverity of CTVA. Interpretation: CTVA patients showed a good clinical response to antiasthma treatments, and the treatment effects may be related to the severity of CTVA. Trial Registration: ClinicalTrials.gov identifier: NCT 03237221 Funding: 1.This study was supported by the Zhejiang Medical and Health Science and Technology program from Health Commission of Zhejiang Province (WKJ2014-ZJ-01412). 2.This work was funded by the Precision Medicine Research of The National Key Research and Development Plan of China (2016YFC0905800). 3.This study was supported by the program for the Key Site of National Clinical Research Center for Respiratory Disease, the Key ScienceTechnology Innovation Team of Zhejiang Province (2011R50016). Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: The study was approved by the Institutional Review Board for Human Studies of Second Affiliated Hospital of Zhejiang University School of Medicine (Hangzhou, China).

Vortex Whistle and Smart Phone Application for Peak Flow Recordings in Asthmatic Children: A Feasibility Study.

Introduction: Variable airflow obstruction that can be confirmed by diurnal variability of peak expiratory flow (PEF) >13% is an important characteristic of asthma. Home monitoring of PEF may be helpful to diagnose and monitor asthma. In this feasibility study, we aimed to study if asthmatic children can measure PEF at home twice daily during a 4-week period using a device designed as a “whistle” and a smart phone software application.Materials and Methods: Twice daily during 4 weeks, children aged 5–12 years with current asthma rated their asthma condition electronically on the smart phone application Blowfish before inhaling deeply then exhaling into the device to produce a high-pitched sound recorded by the application. Through mathematical algorithms, the sound was transferred to PEF, which was uploaded to a server. At inclusion, the Pediatric Asthma Quality of Life Questionnaire and the Childhood Asthma Control Test were answered. At the end, the parents graded the device and application.Results: One child did not manage to upload PEF. For the remaining 21 children, the median (quartiles) days with at least one measurement during the period were 27 (21–29.5), and on median 18 (9–24) days PEF was recorded twice daily. The median parental score (potential score 0–20) of the application was 18 (15–20).Discussion/Conclusion: The study shows promising results for home monitoring of PEF by an electronic device with automatic teletransmission. The high rate of successful recordings and parental satisfaction suggests that the clinical utility of the solution should be further studied.

Supplementary prevention and management of asthma with quercetin phytosome: a pilot registry.

In association with standard management, natural pharmaceutical standard (PS) supplements may play an important role in managing and preventing mild-to-moderate symptoms of asthma, a significant health issue that impacts patients and the healthcare system. Quercetin is a natural flavonoid with important biological properties (anti-inflammatory, antihistamine and anti-oxidative actions). In this pilot registry, we evaluated the effects of quercetin formulated with the Phytosome® delivery system (Quercefit™, QFit)+standard management (SM) in otherwise healthy subjects with mild-moderate asthmatic attacks and rhinitis. Subjects used either QFit 1 or 2 tabs/day in association with SM or SM only (control group). After 30 days of management, we evaluated the presence of the main signs/symptoms of asthma according to the GINA classification system also considering the need of rescue medication, nasal drops, the use of inhalers, the rhinitis score and oxidative stress. QFit+SM showed superior results compared with SM alone in controlling, preventing and reducing daily and night symptoms, in maintaining higher peak expiratory flow (PEF) and in decreasing PEF variability. The supplementary use of QFit improved additional measures of asthma management, decreasing the use of inhalers, nasal drops, rescue medications and improving the rhinitis score. QFit produced a significantly more evident reduction in oxidative stress compared with SM; Qfit showed a very good safety profile. This preliminary supplement, concept registry shows a potential protective and preventive effect of quercetin on attacks frequency and in controlling the most common signs/symptoms of asthma in the milder cases of the disease.

Regular exercise improves asthma control in adults: A randomized controlled trial

We conducted a randomized controlled trial to test the hypothesis that a 24-week exercise intervention improves asthma control in adults. Adults with mild or moderate asthma were randomly assigned to either the exercise intervention group (IG) or the reference group (RG). Participants in IG received an individualized exercising program, including aerobic exercise at least three times a week for ≥30 minutes, muscle training, and stretching. The primary outcome was asthma control, measured by Asthma Control Test (ACT), asthma-related symptoms, and peak expiratory flow (PEF) variability. We estimated the risk (i.e. probability) of improvement in asthma control and the risk difference (RD) between IG and RG. Of 131 subjects (67 IG/64 RG) entered, 105 subjects (51/54) completed the trial (80%), and 89 (44/45) were analysed (68%). The ACT became better among 26 (62%) participants in IG and among 17 (39%) participants in RG. The effect of intervention on improving asthma control was 23% (RD = 0.23, 95% CI 0.027–0.438; P = 0.0320). The intervention also reduced shortness of breath by 30.1% (RD = 0.301, 95% CI 0.109–0.492; P = 0.003). The change in PEF variability was similar in both groups. Regular exercise improves asthma control measured by the ACT, while has little effect on PEF variability.

Exploring the relevance and extent of small airways dysfunction in asthma (ATLANTIS): baseline data from a prospective cohort study

Small airways dysfunction (SAD) is well recognised in asthma, yet its role in the severity and control of asthma is unclear. This study aimed to assess which combination of biomarkers, physiological tests, and imaging markers best measure the presence and extent of SAD in patients with asthma. In this baseline assessment of a multinational prospective cohort study (the Assessment of Small Airways Involvement in Asthma [ATLANTIS] study), we recruited participants with and without asthma (defined as Global Initiative for Asthma severity stages 1-5) from general practices, the databases of chest physicians, and advertisements at 29 centres across nine countries (Brazil, China, Germany, Italy, Spain, the Netherlands, the UK, the USA, and Canada). All participants were aged 18-65 years, and participants with asthma had received a clinical diagnosis of asthma more than 6 months ago that had been confirmed by a chest physician. This diagnosis required support by objective evidence at baseline or during the past 5 years, which could be: positive airway hyperresponsiveness to methacholine, positive reversibility (a change in FEV1 ≥12% and ≥200 mL within 30 min) after treatment with 400 μg of salbutamol in a metered-dose inhaler with or without a spacer, variability in peak expiratory flow of more than 20% (measured over 7 days), or documented reversibility after a cycle (eg, 4 weeks) of maintenance anti-asthma treatment. The inclusion criteria also required that patients had stable asthma on any previous regular asthma treatment (including so-called rescue β2-agonists alone) at a stable dose for more than 8 weeks before baseline and had smoked for a maximum of 10 pack-years in their lifetime. Control group participants were recruited by advertisements; these participants were aged 18-65 years, had no respiratory symptoms compatible with asthma or chronic obstructive pulmonary disease, normal spirometry, and normal airways responsiveness, and had smoked for a maximum of 10 pack-years. We assessed all participants with spirometry, body plethysmography, impulse oscillometry, multiple breath nitrogen washout, CT (in selected participants), and questionnaires about asthma control, asthma-related quality of life (both in participants with asthma only), and health status. We applied structural equation modelling in participants with asthma to assess the contribution of all physiological and CT variables to SAD, from which we defined clinical SAD and CT SAD scores. We then classified patients with asthma into SAD groups with model-based clustering, and we compared asthma severity, control, and health-care use during the past year by SAD score and by SAD group. This trial is registered with ClinicalTrials.gov, number NCT02123667. Between June 30, 2014, and March 3, 2017, we recruited and evaluated 773 participants with asthma and 99 control participants. All physiological measures contributed to the clinical SAD model with the structural equation modelling analysis. The prevalence of SAD in asthma was dependent on the measure used; we found the lowest prevalence of SAD associated with acinar airway ventilation heterogeneity (Sacin), an outcome determined by multiple breath nitrogen washout that reflects ventilation heterogeneity in the most peripheral, pre-acinar or acinar airways. Impulse oscillometry and spirometry results, which were used to assess dysfunction of small-sized to mid-sized airways, contributed most to the clinical SAD score and differed between the two SAD groups. Participants in clinical SAD group 1 (n=452) had milder SAD than group 2 and comparable multiple breath nitrogen washout Sacin to control participants. Participants in clinical SAD group 2 (n=312) had abnormal physiological SAD results relative to group 1, particularly their impulse oscillometry and spirometry measurements, and group 2 participants also had more severe asthma (with regard to asthma control, treatments, exacerbations, and quality of life) than group 1. Clinical SAD scores were higher (indicating more severe SAD) in group 2 than group 1, and we found that these scores were related to asthma control, severity, and exacerbations. We found no correlation between clinical SAD and CT SAD scores. SAD is a complex and silent signature of asthma that is likely to be directly or indirectly captured by combinations of physiological tests, such as spirometry, body plethysmography, impulse oscillometry, and multiple breath nitrogen washout. SAD is present across patients with all severities of asthma, but it is particularly prevalent in severe disease. The clinical classification of SAD into two groups (a milder and a more severe group) by use of impulse oscillometry and spirometry, which are easy to use, is meaningful given its association with GINA severity stages, asthma control, quality of life, and exacerbations. Chiesi Farmaceutici SpA.

Brittle asthma a report of 2 cases

Brittle asthma, even though it is thought to be a rare form of Asthma, may form the bulk of our difficult to treat asthma and frequently unresponsive exacerbation. Brittle Asthma. Brittle asthma is a rare form of severe asthma characterized by a wide variation of Peak Expiratory Flow (PEF) 1 , in spite of high doses of inhaled steroids and bronchodilator therapy. Brittle asthmatic patients have very serious and often, life threatening, attacks. There are two forms of brittle asthma. Case Presentation We present the cases of a 45yr old Nurse anesthetics who was diagnosed >5yrs ago and a 56yr old unemployed who was diagnosed >15yrs ago. Both have been stable for years on add on maintenance therapy with high doses of inhaled corticosteroid and β 2 agonist as oral salbutamol and an inhaler therapy during exacerbation. Recently, both patients noticed worsening of symptoms despite high dose therapy, They have been in and out of hospital recently for uncontrolled asthma. They later had to be admitted in ICU because of respiratory insufficiency. These two lapsed into brittle asthma with recurrent bronchospasm, due to repeated to anesthetic agents and environmental exposure at home respectively. Keywords: Brittle Asthma, Peak Expiratory Flow (PEF), Respiratory Insufficiency, environmental exposure

NON-INVASIVE PREVENTIVE VENTILATION WITH TWO PRESSURE LEVELS IN THE POSTOPERATIVE PERIOD OF ROUX-EN-Y GASTRIC BYPASS: RANDOMIZED TRIAL.

ABSTRACTBackground:Obesity is characterized by excessive accumulation of body fat, which causes damage to the health of individuals, such as breathing difficulties. Aim:To verify the results of non-invasive ventilation as a preventive strategy on the decline of respiratory function and postoperative complications in patients undergoing Roux-en-Y gastric bypass. Methods:This is a randomized trial, according to CONSORT standards, with obese adults aged 18-40 years. Randomized control group (n=25) only received guidelines regarding posture, early ambulation and cough stimuli, and in the NIV group (n=25), in addition to the aforementioned group, non-invasive ventilation was performed with two pressure levels, once day for 60 min, from the 1st to the 3rd postoperative day (POD). Both groups were evaluated in the preoperative period and in the 1st and 3rd POD for respiratory function, which were: slow vital capacity (VC), inspiratory capacity (IC), minute volume (MV), tidal volume maximal inspiratory muscle strength (Pimax) and peak expiratory flow (PEF). The length of hospital stay and the episodes of postoperative complications were recorded. Results:Of the 50 patients the majority were young adults with degrees of obesity between III and IV. In the intergroup analysis, there was an improvement in the CVL and MV only in the 1st POD in the NIV group, CI in the three moments evaluated in the NIV group and the PFE in the 1st and 3rd PDO also in this group. The most frequent complications were pneumonia, followed by operative wound infection and atelectasis. There was a significant difference between groups, showing a higher occurrence in pneumonia and atelectasis in the control group. The days of hospitalization and intensive care unit were similar. Conclusion:It was observed a faster recovery until the 3rd POD in the IC and PEF variables in the NIV group; in addition, there were fewer complications in this group.