Bronchodilator Response Research Articles

Phenotype and management of chronic obstructive pulmonary disease patients in general population in China: a nationally cross-sectional study

This study aims to investigate the characteristics of the phenotype and management of chronic obstructive pulmonary disease (COPD) patients in the general population in China. We analyzed spirometry-confirmed COPD patients who were identified from a population-based, nationally representative sample in China. All participants were measured with airflow limitation severity based on post-bronchodilator FEV1 percent predicted, bronchodilator responsiveness, exacerbation history, and respiratory symptoms. Among a total of 9134 COPD patients, 90.3% were non-exacerbators, 2.9% were frequent exacerbators without chronic bronchitis, 2.0% were frequent exacerbators with chronic bronchitis, and 4.8% were asthma-COPD overlap. Less than 5% of non-exacerbators ever had pulmonary function testing performed. The utilization rate of inhaled medication in non-exacerbators, exacerbators without chronic bronchitis, exacerbators with chronic bronchitis, and asthma-COPD overlap was 1.4, 23.5, 29.5, and 19.4%, respectively. A comprehensive strategy for the management of COPD patients based on phenotype in primary care is urgently needed.

"Poor Effort" Does Not Account for Reduced Forced Vital Capacity in Asthmatic Children.

Purpose: Poor forced vital capacity (FVC) effort has been considered to be the main reason for FVC reduction by the ATS/ERS guideline; however, this has rarely been mentioned in previous studies. The present study aims to determine whether reduced FVC in asthmatic children is correlated to poor FVC effort.Methods: A total of 209 asthmatic children within 5–13 years old were included and divided into reduced FVC (“restricted,” n = 66) and typical obstruction group (“obstructed,” n = 143). Forced expiratory flows before and after bronchodilation were recorded in asthmatic children. The differences in clinical characteristics, spirometric results, FVC effort, and bronchodilator response were compared between two groups. Exhalation time (ET) was divided into effective ET (ETe) and plateau ET (ETp) by the start point of exhalation plateau on the time-volume curve. FVC effort was assessed by ET, ETp, and back extrapolated volume (EV)/FVC (%).Results: Asthmatic children in the restricted group had significantly higher slow vital capacity (SVC)/FVC (%), higher EV/FVC (%), shorter ET, shorter ETe, and longer ETp, when compared with those with obstructed. In the obstructed group, ET (r = 0.201, P = 0.016) and ETe (r = 0.496, P < 0.001) positively correlated with FVC, and ETp (r = −0.224, P = 0.007) negatively correlated with FVC. In the restricted group, FVC positively correlated with ETe (r = 0.350, P = 0.004) but not ET and ETp. FVC z-score significantly correlated with total IgE (n = 51, r = −0.349, P = 0.012) and with FEF25−75% z-score (n = 66, r = 0.531, P < 0.001) in the restricted group. The further logistic regression revealed that the risk of restricted increased by 1.12 (95% CI, 1.04–1.22, P = 0.005) with every 1% increase in %ΔFVC. In subjects with restricted and bronchodilation tests, %ΔFVC was significantly associated with FeNO (n = 29, r = 0.386, P = 0.039), FEF25−75% z-score (n = 29, r = −0.472, P = 0.010), and SVC/FVC (%) (n = 19, r = 0.477, P = 0.039) but not with EV/FVC (%), ET, ETe, or ETp (P > 0.05).Conclusion: These findings suggested that “poor FVC effort” does not account for the FVC reduction in asthmatic children. Short ET and high SVC/FVC (%) are characteristics of reduced FVC.

Longitudinal Assessment of Pulmonary Function and Bronchodilator Response in Pediatric Patients With Post-infectious Bronchiolitis Obliterans.

Backgroud: Postinfectious bronchiolitis obliterans (PIBO) is a rare respiratory disease. In recent years, the disease has been recognized and diagnosed increasingly in children. Pulmonary function is important for diagnosis, identifying the severity of the PIBO and monitoring progression. But there have been only a few studies that followed the evolution of PIBO on the basis of pulmonary function tests (PFTs).Objective: The study targeted the evolution of pulmonary function and bronchodilator response in a case series of Chinese children with PIBO.Methods: Twelve children between the ages of 6–99 months with PIBO were studied retrospectively from 2009 to 2019. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), the FEV1/FVC ratio, and maximal midexpiratory flow velocity 25–75% (MMEF25−75%) were collected at each PFT, and bronchodilator responses were evaluated. Spirometric parameters were monitored over time, and generalized linear mixed models were used to analyze longitudinal panel data.Results: The median baseline PFT values for FVC, FEV1, the FEV1/FVC ratio, and MMEF25−75% were 41.6, 39.75, 90.7, and 22.2%, respectively. At the initial PFTs, 10 (83.3%) patients demonstrated a significant bronchodilator response. FVC and FEV1 increased by 8.212%/year and 5.007%/year, respectively, and the FEV1/FVC ratio decreased by an average of 3.537%/year. MMEF25−75% showed improvement at an average rate of 1.583% every year. Overall, FEV1 and MMEF25−75% showed different degrees of improvement after the use of inhaled bronchodilators at each PFT session for 10 patients, and FEV1 measures demonstrated significant (>12%) β2-bronchodilation in 56% of PFT sessions.Conclusions: Pediatric patients with PIBO showed an obstructive defect in pulmonary function. The FVC, FEV1, and MMEF25−75% improved as they grew older, while the FEV1/FVC ratio decreased. This may be due to the development of lung parenchyma more than airway growth. Airway obstruction in some patients improved with the use of β2 agonists.

Spirometric Response to Bronchodilator and Eucapnic Voluntary Hyperpnea in Adults With Asthma.

The spirometric response to fast-acting bronchodilator is used clinically to diagnose asthma and in clinical research to verify its presence. However, bronchodilator responsiveness does not correlate with airway hyper-responsiveness measured with the direct-acting stimulus of methacholine, demonstrating that bronchodilator responsiveness is a problematic method for diagnosing asthma. The relationship between bronchodilator responsiveness and airway hyper-responsiveness assessed with indirect-acting stimuli is not known. Retrospectively, the spirometric responses to inhaled bronchodilator and a eucapnic voluntary hyperpnea challenge (EVH) were compared in 39 non-smoking adult subjects with asthma (26 male, 13 female; mean ± SD age 26.9 ± 7.8 y; mean ± SD body mass index 26.3 ± 4.7 kg/m2). All subjects met one or both of 2 criteria: ≥ 12% and 200 mL increase in FEV1 after inhaled bronchodilator, and ≥ 10% decrease in FEV1 after an EVH challenge. Overall, FEV1 increased by 9.9 ± 7.9% after bronchodilator (3.93 ± 0.97 to 4.28 ± 0.91 L, P < .001) and decreased by 23.9 ± 15.0% after the EVH challenge (3.89 ± 0.89 to 2.96 ± 0.88 L, P < .001). However, the change in FEV1 after bronchodilator did not correlate with the change after EVH challenge (r = 0.062, P = .71). Significant bronchodilator responsiveness predicted a positive response to EVH challenge in 9 of 33 subjects (sensitivity 27%). Following EVH, the change in FEV1 strongly correlated with the change in FVC (FEV1 percent change vs FVC percent change, r = 0.831, P < .001; FEV1 ΔL vs FVC ΔL, r = 0.799, P < .001). These results extend previous findings that demonstrate a lack of association between bronchodilator responsiveness and methacholine responsiveness. Given the poor concordance between the spirometric response to fast-acting bronchodilator and the EVH challenge, these findings suggest that the airway response to inhaled β2-agonist must be interpreted with caution and in the context of its determinants and limitations.

Lung mechanics and respiratory morbidities in school-age children born moderate-to-late preterm.

Late and moderate prematurity may have an impact on pulmonary function during childhood. The present study aimed to investigate lung mechanics in school-age children born moderate-to-late preterm (MLPT). Children aged 5-10 years were enrolled in this case-control study. Lung function and bronchodilator response were assessed by impulse oscillometry (IOS) at two hospital-based specialized clinics. A structured questionnaire was employed to assess respiratory morbidities. A total of 123 children was divided into two groups: case (MLPT) n = 52 and control (children born at term) n = 71. The results showed no difference between groups in mean baseline IOS variables: R5 0.80 ± 0.20 vs 0.82 ± 0.22 kPa/L/s, p = 0.594, R20 0.54 ± 0.13 vs 0.55 ± 0.13 kPa/L/s, p = 0.732, R5-R20 0.26 ± 0.12 vs 0.27 ± 0.15 kPa/L/s, p = 0.615, X5 -0.29 ± 0.01 vs -0.29 ± 0.1 kPa/L/s, p = 0.990, Fres 21.1 ± 3.3 vs 21.7 ± 3.1 L/s, p = 0.380, and AX 2.7 ± 3.36 vs 2.5 ± 1.31 kPa/L/s, p = 0.626. Bronchodilator response and the occurrence of respiratory morbidities after birth were also similar between groups. This study found lung mechanics parameters to be similar in school-age children born MLPT and those born at term, suggesting that pulmonary plasticity continues to occur in children up to school age. Late and moderate prematurity is associated with an increased risk of reduced pulmonary function during childhood. Follow-up reports in adolescents and adults born MLPT are scarce but have indicated pulmonary plasticity with normalization of airway function. Our results show that the lung function in school-age children born MLPT is similar to that of children born at term.

Bronchodilator response and lung function decline: Associations with exhaled nitric oxide with regard to sex and smoking status

BackgroundFractional exhaled nitric oxide (FeNO) is a marker of type-2 inflammation used both to support diagnosis of asthma and follow up asthma patients. The associations of FeNO with lung function decline and bronchodilator (BD) response have been studied only scarcely in large populations. ObjectivesTo study the association between FeNO and a) retrospective lung function decline over 20 years, and b) lung function response to BD among asthmatic subjects compared with non-asthmatic subjects and with regards to current smoking and sex. MethodsLongitudinal analyses of previous lung function decline and FeNO level at follow-up and cross-sectional analyses of BD response and FeNO levels in 4257 participants (651 asthmatics) from the European Community Respiratory Health Survey. ResultsAmong asthmatic subjects, higher percentage declines of FEV1 and FEV1/FVC were associated with higher FeNO levels (p = 0.001 for both) at follow-up. These correlations were found mainly among non-smoking individuals (p = 0.001) and females (p = 0.001) in stratified analyses.Percentage increase in FEV1 after BD was positively associated with FeNO levels in non-asthmatic subjects. Further, after stratified for sex and smoking separately, a positive association was seen between FEV1 and FeNO levels in non-smokers and women, regardless of asthma status. ConclusionsWe found a relationship between elevated FeNO and larger FEV1 decline over 20 years among subjects with asthma who were non-smokers or women. The association between elevated FeNO levels and larger BD response was found in both non-asthmatic and asthmatic subjects, mainly in women and non-smoking subjects.

Diagnostic performance of lung volumes in assessment of reversibility in chronic obstructive pulmonary disease

BackgroundReversibility measured by spirometry in chronic obstructive pulmonary disease (COPD) is defined as an increase in forced expiratory volume in first second (FEV1) that is both more than 12% and 200 mL above the pre-bronchodilator value in response to inhaled bronchodilators. FEV1 only may not fully reverberate the changes caused by reduction in air trapping or hyperinflation. To date, the studies that examined the effect of inhaled bronchodilators (BD) on residual volume (RV) and total lung capacity (TLC) are limited. This study was carried out to assess the differences between flow and volume responses after bronchodilator reversibility testing in patients with different COPD GOLD stages (GOLD stage I to stage IV). Spirometry and whole body plethysmography were done before and 15 min after inhalation of 400 μg salbutamol.ResultsMajority (53.3%) of cases were volume responders, 18.7% were flow responders, 20% were flow and volume responders, and 8% were non responders. Significant increase in Δ FEV1% was found in 15% of cases while 55% showed a significant increase in Δ FVC (P= < 0.001). Mean difference of Δ FVC (L) post BD was significantly increased with advancing GOLD stage (P= 0.03). A cutoff point > 20% for Δ RV% had 70% sensitivity and 60% specificity and > 12% for Δ TLC% showed 90% sensitivity and 45% specificity for prediction of clinically significant response to BD based on FEV1. A cutoff point > 18% for Δ RV% had 78% sensitivity and 29% specificity and > 14% for Δ TLC% had 50% sensitivity and 70% specificity for prediction of clinically significant response to BD based on FVC.ConclusionΔFEV1 underestimates the true effect of bronchodilators with advancing GOLD stage. Measurement of lung volumes in addition to the standard spirometric indices is recommended when determining bronchodilator response in COPD patients.

Función pulmonar evolutiva evaluada por oscilometría de impulso en prescolares con asma

Impulse oscillometry (IOS) is useful for measuring lung function in preschool children. Our objective was to describe the alterations and evolutionary profile of IOS in asthmatic children under 6 years of age after one year of follow-up. Patients and Method: 62 preschoolers performed IOS at the beginning of the study and after one year. The proportion of altered IOS and bronchodilator response (BR +) at both times was compared, in addition to sub-analysis according to asthma control and presence of atopy. For the statistical analysis, we used McNemar’s c² and the Student’s t-test with a 5% α error. Results: The initial IOS was altered in 80.6% and in 64.5%% after one year (p = 0.04). 77.4% of the children presented BR+ at the beginning of the study and 83.9% after one year. The uncontrolled asthma group presented a significant improvement in the X5 and D5-20 means, but the controlled asthma group did not. In atopic patients, only uncontrolled asthmatics improved X5, AX, and D5-20. Conclusion: IOS shows alterations in a high percentage of preschoolers with uncontrolled asthma, which decreases significantly at one year, but remains altered and with BR + in most children. Additional studies are required to identify different preschool asthma phenotypes and their evolution with treatment.

Bronchodilator responsiveness in cystic fibrosis children treated for pulmonary exacerbations.

Cystic fibrosis (CF) pulmonary exacerbations (PEx) are associated with a significant drop in pulmonary function. The clinical value of measuring bronchodilator (BD) responsiveness during treatment for PEx to monitor or predict recovery of lung function is unclear. A retrospective analysis of spirometry with BD response testing obtained during hospital admissions for PEx in pediatric CF patients. Repeated events were included for patients with BD testing during multiple admissions. Two hundred forty-nine spirometries with BD testing in 102 patients were completed around Day 7 (Days 4-10) of hospital admission for treatment of CF PEx. Median (IQR) forced expiratory volume in 1 s (FEV1 ) was 70.6% predicted (58.1, 84.6) before the PEx event (best FEV1 in 6 months before admission), 54.4% (41.5, 66.9) at admission, 62.3% (48.4, 74.7) around Day 7 of admission and 67.1% predicted (53.8, 78.2) at the end of treatment. BD response around Day 7 correlated poorly with FEV1 before PEx (r = -.16, p = .02) and did not correlate with recovery to baseline FEV1 at end of treatment (r = .08, p = .22). Only 23/249 (9%) individual tests had a BD response in FEV1 of ≥12% and 200 ml. BD response was not related to age or severity of lung disease and led to an immediate change in clinical management in only four cases. Significant BD response in CF patients treated for PEx is rare, shows poor correlation with baseline pulmonary function and does not correlate with the recovery of FEV1 with treatment. These data suggest that routine testing for BD response is not indicated during PEx.

Pharmacogenetic Polygenic Risk Score for Bronchodilator Response in Children and Adolescents with Asthma: Proof-of-Concept.

Genome-wide association studies (GWAS) of response to asthma medications have primarily focused on Caucasian populations, with findings that may not be generalizable to minority populations. We derived a polygenic risk score (PRS) for response to albuterol as measured by bronchodilator response (BDR), and examined the PRS in a cohort of Hispanic school-aged children with asthma. We leveraged a published GWAS of BDR to identify relevant genetic variants, and ranked the top variants according to their Combined Annotation Dependent Depletion (CADD) scores. Variants with CADD scores greater than 10 were used to compute the PRS. Once we derived the PRS, we determined the association of the PRS with BDR in a cohort of Hispanic children with asthma (the Genetics of Asthma in Costa Rica Study (GACRS)) in adjusted linear regression models. Mean BDR in GACRS participants was5.6% with a standard deviation of 10.2%. We observed a 0.63% decrease in BDR in response to albuterol for a standard deviation increase in the PRS (p = 0.05). We also observed decreased odds of a BDR response at or above the 12% threshold for a one standard deviation increase in the PRS (OR = 0.80 (95% CI 0.67 to 0.95)). Our findings show that combining variants from a pharmacogenetic GWAS into a PRS may be useful for predicting medication response in asthma.

Assessing compliance with bronchodilator responsiveness testing methods by practicing allergists

Bronchodilator responsiveness testing combined with clinical evaluation is a critical component for determining a patient's asthma control and management strategy.1 The bronchodilator response depends on several factors, such as severity of airflow obstruction and spirometric parameters considered for the functional response to the bronchodilator agent.2 This study was performed to determine how bronchodilator responsiveness tests are being administered in allergy practices, focusing on compliance and standardization with American Thoracic Society (ATS) guidelines for conducting this test.

Distinct lung function and bronchodilator responses between term and preterm young children with recurrent wheezing

Recurrent or unresolved wheezing is a common complaint in certain young children populations, especially those born preterm. Using infant lung function testing, we aimed to distinguish the differences between term and preterm young children with recurrent wheezing. Children under 2 years of corrected age were enrolled if they had 3 or more wheezing episodes during the enrollment period. Healthy term controls of comparable age were also recruited for reference. Measurements of lung function were made, including tidal breathing, passive respiratory mechanics, and forced tidal and raised-volume expiration. For children with recurrent wheezing, raised-volume forced expiration was repeated after an adequate delivery of bronchodilator nebulization was achieved. In total, 68 young children (40 with recurrent wheezing and 28 healthy controls) were recruited. Among children with recurrent wheezing, 23 preterm children (preterm group), and 17 term children (term group) were enrolled. Compared with healthy controls, both the term and preterm groups had lower lung function as measured by absolute values and z scores. The term group performed worse than the preterm group with regard to forced vital capacity, forced expiratory volume at 0.5s (FEV0.5), and peak expiratory flow. Following bronchodilator nebulization, the term group had significantly higher increases in FEV0.5 and forced mid-expiratory flow than the preterm group. Young children with recurrent wheezing, especially term infants, demonstrated lower lung function than healthy controls. Moreover, the term group evidenced greater responsiveness to bronchodilators than the preterm group. The distinct bronchodilator responses may offer further information to guide the diagnosis and treatment of young children with recurrent wheezing.

The ‘clinically significant’ bronchodilator responsiveness (BDR) in children: a comparative study between six definitions of scholarly societies and a mini-review

ABSTRACT Objective: To compare the percentages of children with and without airway obstruction (obstructive and non-obstructive groups, respectively) presenting a ‘clinically significant’ BDR according to the following definitions: GINA: FEV1 increase >12% predicted (∆Predicted), ATS/ERS: FEV1 increase ≥12% initial (∆Initial) and ∆FEV1 absolute (∆) ≥200 ml and/or ∆FVCInitial ≥12% and ∆FVC ≥200 ml, British thoracic society (BTS): ∆FEV1Initial ≥12%, National asthma education and prevention program (NAEPP): ∆FEV1Initial ≥12% and ∆FEV1 > 200 ml, Group of research on advances in pediatric pneumology: ∆FEV1Initial ≥12% or ∆PEFInitial ≥20%, and South African thoracic society (SATS): ∆FEV1Initial ≥12% or ∆FEV1 >200 ml and/or ∆FVCInitial ≥12% or ∆FVC >200 ml. Methods: This was a multicenter comparative study involving 278 children aged 6 to16 years: obstructive group (FEV1/FVC < lower-limit-of-normal, n = 116) and non-obstructive group (FEV1/FVC ≥ lower-limit-of-normal, n = 162). Spirometry was performed before/after a bronchodilator test. The Cochrane Q test was used to compare the percentage of responders according to the six definitions. Results: The percentages of responders among the obstructive [ranging from 51.72 (NAEPP) to 74.14% (SATS)] and the non-obstructive [ranging from 0.62 (NAEPP, BTS) to 8.64% (SATS)] groups were definition-dependent. Conclusion: In children, a ‘clinically significant’ BDR is definition-dependent.

Predictors of Single Bronchodilation Treatment Response for COPD: An Observational Study with the Trace Database Cohort.

Chronic obstructive pulmonary disease (COPD) patients constitute a heterogeneous population in terms of treatment response. Our objective was to identify possible predictive factors of response to treatment with single bronchodilation monotherapy in patients diagnosed with COPD. The Time-based Register and Analysis of COPD Endpoints (TRACE; clinicaltrials.gov NCT03485690) is a prospective cohort of COPD patients who have been attending annual visits since 2012. Patients who were kept on a single bronchodilator during the first year of follow-up were selected. The responders were defined according to all of the following variables: any improvement in morning post-dose forced expiratory volume in 1 s or deterioration <100 mL, no change or improvement in dyspnea score, and no occurrence of exacerbations. Significant and plausible variables were analyzed using a proportional hazard Cox regression for single bronchodilator responders. We analyzed 764 cases, of whom 128 (16.8%) were receiving monotherapy with one bronchodilator. Of these, 85 patients (66.4%) were responders. Factors affecting responder status were: female gender (hazard ratio (HR) 0.276; 95% confidence interval (CI) 0.089–0.858), dyslipidemia (HR 0.436; 95%CI 0.202–0.939), not performing regular exercise (HR 0.523; 95%CI 0.254–1.076), active smoking (HR 0.413; 95%CI 0.186–0.920), and treatment adherence (HR 2.527; 95%CI 1.271–5.027). The factors associated with a single bronchodilation response are mainly non-pharmacological interventions and comorbidities.

Bronchodilator reversibility testing in post-COVID-19 patients undergoing pulmonary rehabilitation

BackgroundThe usefulness of bronchodilators in coronavirus diseases 2019 (COVID-19) survivors is still uncertain, especially for patients with a concomitant obstructive lung disease. We aimed at verifying the level of bronchodilator reversibility in COVID-19 patients undergoing multidisciplinary pulmonary rehabilitation after the acute phase. MethodsWe enrolled 105 consecutive patients referring to the Pulmonary Rehabilitation Unit of Istituti Clinici Scientifici Maugeri Spa SB, IRCCS of Telese Terme, Benevento, Italy after being discharged from the COVID-19 acute care ward and after recovering from acute COVID-19 pneumonia. All subjects performed a spirometry before and after inhalation of salbutamol 400 μg to determine the bronchodilation response within 48 h of admission to the unit. ResultsAll patients had suffered from a moderate to severe COVID-19, classified 3 or 4 according to the WHO classification, Seventeen patients had concomitant obstructive lung disease (14 suffering from COPD and 3 from asthma). FEV1 after salbutamol improved on average by 41.7 mL in the entire examined sample, by 29.4 mL in subjects without concomitant obstructive lung diseases, by 59.3 mL in COPD patients and by 320.0 mL in asthma patients. Mean FVC after salbutamol improved by 65.7 mL in the entire examined sample, by 52.5 mL in subjects without concomitant obstructive lung diseases, by 120.0 mL in COPD patients, and by 200.0 mL in asthma patients. ConclusionsThis study suggests that a treatment with bronchodilators must always be taken into consideration in post-COVID-19 patients because it can induce a functional improvement that, even if small, can facilitate the breathing of these patients.

Single Nucleotide Polymorphisms (SNPs) in PRKG1 & SPATA13-AS1 are associated with bronchodilator response: a pilot study during acute asthma exacerbations in African American children.

Inhaled bronchodilators are the first-line treatment for asthma exacerbations, but individual bronchodilator response (BDR) varies by race and ethnicity. Studies have examined BDR's genetic underpinnings, but many did not include children or were not conducted during an asthma exacerbation. This pilot study tested single-nucleotide polymorphisms' (SNPs') association with pediatric African American BDR during an acute asthma exacerbation. This was a study of pediatric asthma patients in the age group 2-18 years treated in the emergency department for an asthma exacerbation. We measured BDR before and after inhaled bronchodilator treatments using both the Pediatric Asthma Severity Score (PASS) and asthma severity score. We collected genomic DNA and examined whether 21 candidate SNPs from a review of the literature were associated with BDR using crude odds ratios (OR) and adjusted analysis. The final sample population was 53 children, with an average age of 7.2 years. The average initial PASS score (scale of ascending severity from 0 to 6) was 2.5. After adjusting for BMI, age category, gender and smoke exposure, rs912142 was associated with decreased odds of having low BDR (OR, 0.20; 95% confidence interval (CI), 0.02-0.92), and rs7081864 and rs7903366 were associated with decreased odds of having high BDR (OR, 0.097; 95% CI, 0.009-0.62). We found three SNPs significantly associated with pediatric African American BDR that provide information regarding a child's potential response to emergency asthma exacerbation treatment. Once validated in larger studies, such information could guide pharmacogenomic evidence-based emergency asthma treatment to improve patient outcomes.

The bronchodilator test in patients with airway obstruction: the responsiveness of lung function parameters

Interpretation of bronchodilator (BD) test based on reaction of forced expiratory in one second (FEV 1). For assessing bronchodilator responsiveness of lung volumes, airway resistance remains largely unexplored. Therefore, we assessed the response of pulmonary function parameters to BD to reveal the most responsive parameter. 90 patients with chronic airway obstruction (61 male and 29 female; aged 55±11; post- BD FEV 1 was 63.1+18.3 % predicted) performed spirometry and static lung volume measurements before and after inhalation of BD. We calculated effect size (ES) for each parameter from the difference between two means divided by the standard deviation of baseline score. There was a significant increase both FVC and FEV 1by 8.2 and 12.3 % from baseline (p&lt;0.001). ES were 0.34 for FEV1 and 0.26 for FVC. The ES for lung volumes were from -0.07 (total lung capacity) to -0.31 (residual volume). The ES for sRtot (specific airway resistance) was -0.5 and ES for sGeff (specific effective airway conductance) was 0.95. The parameters of airway resistance and conductance were more responsive for the assessment of pulmonary function changes than spirometry and lung volumes parameters in patients with chronic airway obstruction.

Diet and lung disease-Are fruits and vegetables the ideal whole-food intervention?

Diet and lung disease-Are fruits and vegetables the ideal whole-food intervention?

Effect of different accessory devices on the dose delivered from pressurised metred-dose inhalers.

Improved aerosol delivery of bronchodilators to chronic obstructive pulmonary disease (COPD) subjects is a cornerstone in the treatment approach. Drug delivery and response are improved with the use of accessory devices [spacers and valved holding chambers (VHCs)] with metred-dose inhalers (pMDIs). However, different accessory devices are available in the market with different properties that could affect aerosol delivery. Thus, this study aimed to assess the relative lung deposition and systemic bioavailability and compare bronchodilator response of salbutamol delivered using different accessory devices attached to pMDIs. Twelve healthy subjects and twelve COPD subjects inhaled 300 μg salbutamol (3 pMDI puffs) using five different accessory devices with either masks or mouthpieces (Able, Aerochamber plus flow Vu, Dolphin chamber, Tipshaler spacer, and modified Drink bottle spacer). Urine samples were collected thirty minutes post-dosing and cumulatively for the next twenty-four hours, to determine and compare the relative lung deposition [0-0.5 hour excretion of urinary salbutamol (USAL0.5)] and systemic bioavailability [0.5-24hours excretion of urinary salbutamol (USAL24)] of salbutamol from the selected accessory devices. Also, the difference between pre and post-inhalation forced expiratory volume in one second (ΔFEV1 %) of predicted was determined for each accessory device. Urinary excretion of salbutamol (both USAL0.5 and USAL24 samples) in COPD subjects was significantly (P<.05) lower than in healthy subjects for all accessory devices. USAL0.5 and USAL24 in non-antistatic spacers (modified Drink bottle spacer and Dolphin chamber spacers) were significantly lower (P<.05) than that for antistatic spacers (Aerochamber plus flow Vu, Able and Tips-haler). No significant difference in USAL0.5 and USAL24 was observed between facemasks and mouthpieces. There was a significant difference (P<.05) in ΔFEV1 % of predicted values between COPD subjects and healthy subjects. However, within the COPD group and the healthy group there was no significant difference in ΔFEV1 % of predicted values between all accessory devices or between with mouthpiece or with a mask. COPD subjects had lower aerosol delivered compared with healthy subjects. Anti-static accessory devices delivered a higher amount of aerosol compared with non-antistatic accessory devices. Even though the presence of a significant difference in aerosol delivery between non-antistatic and antistatic accessory devices no significant difference was found in the ΔFEV1 % between all accessory devices.

Bronchopulmonary dysplasia as a determinant of respiratory outcomes in adult life.

Respiratory disease is unfortunately common in preterm infants with the archetype being bronchopulmonary dysplasia (BPD). BPD affects approximately 50,000 preterm infants in the U.S. annually with substantial morbidity and mortality related to its pathology (alveolar, airway, and pulmonary vasculature maldevelopment). Predicting the likelihood and severity of chronic respiratory disease in these children as they age is difficult and compounded by the lack of consistent phenotyping. Barriers to understanding the actual scope of this problem include few longitudinal studies, information limited by small retrospective studies and the ever-changing landscape of therapies in the NICU that affect long-term respiratory outcomes. Thus, the true burden of adult respiratory disease caused by premature birth is currently unknown. Nevertheless, limited data suggest that a substantial percentage of children with a history of BPD have long-term respiratory symptoms and persistent airflow obstruction associated with altered lung function trajectories into adult life. Small airway disease with variable bronchodilator responsiveness, is the most common manifestation of lung dysfunction in adults with a history of BPD. The etiology of this is unclear however, developmental dysanapsis may underlie the airflow obstruction in some adults with a history of BPD. This type of flow limitation resembles that of aging adults with chronic obstructive lung disease with no history of smoking. It is also unclear whether lung function abnormalities in people with a history of BPD are static or if these individuals with BPD have a more accelerated decline in lung function as they age compared to controls. While some of the more significant mediators of lung function, such as tobacco smoke and respiratory infections have been identified, more work is necessary to identify the best means of preserving lung function for individuals born prematurely throughout their lifespan.