Asthma Lung Function Research Articles

Assessing the Impact of Spatial and Temporal Variability in Fine Particulate Matter Pollution on Respiratory Health Outcomes in Asthma and COPD Patients.

Ambient air pollution's health impacts are well documented, yet the domestic environment remains underexplored. We aimed to compare indoor versus outdoor (I/O) air quality and estimate the association between indoor/ambient fine particulate matter (PM2.5) exposure and lung function in asthma and chronic obstructive pulmonary disease (COPD) patients. The study involved 24 h monitoring of PM2.5 levels indoors and outdoors, daily peak expiratory flow (PEF), and biweekly symptoms collection from five patients with asthma and COPD (average age of 50 years, 40% male) over a whole year. Data analysis was performed with linear mixed effect models for PEF and generalized estimating equations (GEE) for exacerbations. More than 5 million PM2.5 exposure and meteorological data were collected, demonstrating significant I/O PM2.5 ratio variability with an average ratio of 2.20 (±2.10). Identified indoor PM2.5 sources included tobacco use, open fireplaces, and cooking, resulting in average indoor PM2.5 concentrations of 63.89 μg/m3 (±68.41), significantly exceeding revised World Health Organization (WHO) guidelines. Analysis indicated a correlation between ambient PM2.5 levels and decreased PEF over 0-to-3-day lag, with autumn indoor exposure significantly impacting PEF and wheezing. The study underscores the need to incorporate domestic air quality into public health research and policy-making. A personalized approach is required depending on the living conditions, taking into account the exposure to particulate pollution.

The impact of inflammatory cells on lung function in asthmatics in a cross sectional retrospect study

BackgroundLimited data exists on the impact of inflammatory cells and clinical characteristics on lung function in individuals with asthma. ObjectiveThe objective is to examine the correlation between increased inflammatory cells, asthma symptoms, and lung function in patients with asthma in a clinical setting. MethodsA retrospective cohort study was conducted on 234 individuals suspected of having asthma in Xian, China between January 2008 and December 2021. Of those, 143 patients with complete clinical feature and lung function data were enrolled to examine the relationship between increased inflammatory cells, asthma symptoms, and lung function. Basic characteristics, blood eosinophil count, blood neutrophil count, blood platelet count, blood C-reactive protein (CRP), and comprehensive lung function analysis were evaluated at each inpatient for the 143 adult asthmatics. The association between inflammatory cells and clinical parameters with pulmonary function was compared. ResultsThe results of the study showed that individuals in the alcohol intake group had elevated blood eosinophil count compared to those in the non-alcohol intake group (P = 0.024). Long-acting inhaled beta 2 agonists and antibiotic therapy were associated with lower blood eosinophil count (P = 0.021 and P = 0.049, respectively) compared to other therapy. There was a independent association between blood eosinophil counts and FEV1 pre- and post-therapy in asthma but there was a markedly correlation between blood eosinophil counts and FEV1/FVC pre-and post-therapy in Asthma (P = 0.007). Blood neutrophil counts were inversely correlated with FEV1/FVC after treatment (P = 0.032). Night onset in asthma was positively correlated with blood neutrophil counts, while fever was negatively correlated with blood CRP (P = 0.028). Platelet counts >300 × 109/L after treatment were significantly associated with a decline in FEV (<0.001) in patients with asthma. Elevated blood eosinophil count was independently associated with clinical features in asthma. ConclusionsBased on the study's findings, there is a significant decline in FEV1/FVC among individuals with elevated blood eosinophil count, both pre- and post-bronchodilator while there was a independent relationship between blood eosinophil counts and FEV1 pre-and post-therapy in asthma. This suggests that increased levels of eosinophils may independently associated contribute to reduced lung function in asthma patients.

Redefining asthma management: Remodeling, rehabilitation and remission

Addressing the multifaceted aspects of asthma care calls for a thorough examination of new evidence regarding additional effects of treatments, as well as pioneering a paradigm shift in treatment outcomes. The concept of “people remodeling” unveils the complex interplay between changes in body weight and the use of oral corticosteroids, particularly highlighting how obesity, often a consequence of medication side effects, significantly influences asthma management. Simultaneously, integrating exercise into asthma treatment has undergone a transformative evolution, shifting from careful consideration to a pivotal cornerstone. Within the landscape of severe asthma treatment, the introduction of biological therapies has triggered a profound revolution by presenting the possibility of achieving clinical/complete remission, representing a departure from the conventional control goal. This review will discuss recent articles focusing on weight loss associated with biologics in patients with severe asthma, the effects of exercise on lung function in asthmatics and a consensus definition of clinical remission in severe asthma.

5-HTP inhibits eosinophilia via intracellular endothelial 5-HTRs; SNPs in 5-HTRs associate with asthmatic lung function

BackgroundPrevious research showed that 5-hydroxytryptophan (5HTP), a metabolic precursor of serotonin, reduces allergic lung inflammation by inhibiting eosinophil migration across endothelial monolayers.ObjectiveIt is unknown if serotonin receptors are involved in mediating this 5HTP function or if serotonin receptor (HTR) single nucleotide polymorphisms (SNPs) associate with lung function in humans.MethodsSerotonin receptor subtypes were assessed by qPCR, western blot, confocal microscopy, pharmacological inhibitors and siRNA knockdown. HTR SNPs were assessed in two cohorts.ResultsPharmacological inhibition or siRNA knockdown of the serotonin receptors HTR1A or HTR1B in endothelial cells abrogated the inhibitory effects of 5HTP on eosinophil transendothelial migration. In contrast, eosinophil transendothelial migration was not inhibited by siRNA knockdown of HTR1A or HTR1B in eosinophils. Surprisingly, these HTRs were intracellular in endothelial cells and an extracellular supplementation with serotonin did not inhibit eosinophil transendothelial migration. This is consistent with the inability of serotonin to cross membranes, the lack of selective serotonin reuptake receptors on endothelial cells, and the studies showing minimal impact of selective serotonin reuptake inhibitors on asthma. To extend our HTR studies to humans with asthma, we examined the CHIRAH and GALA cohorts for HTR SNPs that affect HTR function or are associated with behavior disorders. A polygenic index of SNPs in HTRs was associated with lower lung function in asthmatics.ConclusionsSerotonin receptors mediate 5HTP inhibition of transendothelial migration and HTR SNPs associate with lower lung function. These results may serve to aid in design of novel interventions for allergic inflammation.

A 12-week double-blind randomised controlled trial investigating the effect of dietary supplementation with 5000 μg/d (125 µg/d) vitamin D in adults with asthma.

Vitamin D deficiency has previously been linked to higher rates of exacerbation and reduced lung function in asthmatics. Previous randomised controlled trials investigating the effect of vitamin D supplementation have mainly focused on children with asthma. Trials involving adults have typically used bolus dosing regimens, and the main outcomes have been patient-focused without investigating underlying inflammation. The present study aimed to conduct a 12-week placebo-controlled randomised controlled trials administering a daily 5000 μg (125 µg) vitamin D3 supplement to adults with mild to moderate asthma. A total of 32 participants were randomised to receive either the 5000 μg vitamin D3 supplement or an identical matching placebo. The primary outcome of the study was lung function measured by the ratio of FEV1:FVC (effect size 2·5) with secondary outcomes including asthma symptoms and inflammatory biomarkers. There was a small but statistically significant higher increase in the mean (±sd) ratio of FEV1:FVC from baseline to post-intervention in the vitamin D group (+0·05 ± 0·06) compared with the placebo group (+0·006 ± 0·04, P = 0·04). There was no effect of the intervention on asthma control test scores, or the inflammatory biomarkers measured. There was a moderate, significant association between baseline plasma 25(OH)D concentration and baseline plasma IL-10 (r = 0·527, P = 0·005) and TNF-α (r = −0·498. P = 0·008) concentrations. A daily vitamin D3 supplement led to slightly improved lung function in adult asthmatics and may be a useful adjunct to existing asthma control strategies, particularly for individuals with suboptimal vitamin D status.

Regional variations in allergen-induced airway inflammation correspond to changes in soluble guanylyl cyclase heme and expression of heme oxygenase-1.

Asthma is characterized by airway remodeling and hyperreactivity. Our earlier studies determined that the nitric oxide (NO)-soluble guanylyl cyclase (sGC)-cGMP pathway plays a significant role in human lung bronchodilation. However, this bronchodilation is dysfunctional in asthma due to high NO levels, which cause sGC to become heme-free and desensitized to its natural activator, NO. In order to determine how asthma impacts the various lung segments/lobes, we mapped the inflammatory regions of lungs to determine whether such regions coincided with molecular signatures of sGC dysfunction. We demonstrate using murine models of asthma (OVA and CFA/HDM) that the inflamed segments of these murine lungs can be tracked by upregulated expression of HO1 and these regions in turn overlap with regions of heme-free sGC as evidenced by a decreased sGC-α1β1 heterodimer and an increased response to heme-independent sGC activator, BAY 60-2770, relative to naïve uninflamed regions. We also find that NO generated from iNOS upregulation in the inflamed segments has a higher impact on developing heme-free sGC as increasing iNOS activity correlates linearly with elevated heme-independent sGC activation. This excess NO works by affecting the epithelial lung hemoglobin (Hb) to become heme-free in asthma, thereby causing the Hb to lose its NO scavenging function and exposing the underlying smooth muscle sGC to excess NO, which in turn becomes heme-free. Recognition of these specific lung segments enhances our understanding of the inflamed lungs in asthma with the ultimate aim to evaluate potential therapies and suggest that regional and not global inflammation impacts lung function in asthma.

Sex Differences in Lung Function in Asthma Across the Ages

Sex Differences in Lung Function in Asthma Across the Ages

Decreased TLR7 expression was associated with airway eosinophilic inflammation and lung function in asthma: evidence from machine learning approaches and experimental validation

BackgroundAsthma is a global public health concern. The underlying pathogenetic mechanisms of asthma were poorly understood. This study aims to explore potential biomarkers associated with asthma and analyze the pathological role of immune cell infiltration in the disease.MethodsThe gene expression profiles of induced sputum were obtained from Gene Expression Omnibus datasets (GSE76262 and GSE137268) and were combined for analysis. Toll-like receptor 7 (TLR7) was identified as the core gene by the intersection of two different machine learning algorithms, namely, least absolute shrinkage and selector operation (LASSO) regression and support vector machine-recursive feature elimination (SVM-RFE), and the top 10 core networks based on Cytohubba. CIBERSORT algorithm was used to analyze the difference of immune cell infiltration between asthma and healthy control groups. Finally, the expression level of TLR7 was validated in induced sputum samples of patients with asthma.ResultsA total of 320 differential expression genes between the asthma and healthy control groups were screened, including 184 upregulated genes and 136 downregulated genes. TLR7 was identified as the core gene after combining the results of LASSO regression, SVM-RFE algorithm, and top 10 hub genes. Significant differences were observed in the distribution of 13 out of 22 infiltrating immune cells in asthma. TLR7 was found to be closely related to the level of several infiltrating immune cells. TLR7 mRNA levels were downregulated in asthmatic patients compared with healthy controls (p = 0.0049). The area under the curve of TLR7 for the diagnosis of asthma was 0.7674 (95% CI 0.631–0.904, p = 0.006). Moreover, TLR7 mRNA levels were negatively correlated with exhaled nitric oxide fraction (r = − 0.3268, p = 0.0347) and the percentage of peripheral blood eosinophils (%) (r = − 0.3472, p = 0.041), and positively correlated with forced expiratory volume in the first second (FEV1) (% predicted) (r = 0.3960, p = 0.0071) and FEV1/forced vital capacity (r = 0.3213, p = 0.0314) in asthmatic patients.ConclusionsDecreased TLR7 in the induced sputum of eosinophilic asthmatic patients was involved in immune cell infiltration and airway inflammation, which may serve as a new biomarker for the diagnosis of eosinophilic asthma.

Relationships between symptoms and lung function in asthma and/or chronic obstructive pulmonary disease in a real-life setting: the NOVEL observational longiTudinal studY.

The relationships between spirometric assessment of lung function and symptoms (including exacerbations) in patients with asthma and/or chronic obstructive pulmonary disease (COPD) in a real-life setting are uncertain. To assess the relationships between baseline post-bronchodilator (post-BD) spirometry measures of lung function and symptoms and exacerbations in patients with a physician-assigned diagnosis of asthma and/or COPD. The NOVEL observational longiTudinal studY (NOVELTY) is a global, prospective, 3-year observational study. Logistic regression analysis was used to evaluate relationships. Spirometry measures were assessed as percent predicted (%pred). Symptoms were assessed at baseline, and exacerbations were assessed at baseline and Year 1. A total of 11,181 patients in NOVELTY had spirometry data (asthma, n = 5903; COPD, n = 3881; asthma + COPD, n = 1397). A 10% lower post-BD %pred forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) - adjusted for age and sex - were significantly associated with dyspnea (modified Medical Research Council ⩾ grade 2), frequent breathlessness [St George's Respiratory Questionnaire (SGRQ)], frequent wheeze attacks (SGRQ), nocturnal awakening (Respiratory Symptoms Questionnaire; ⩾1 night/week), and frequent productive cough (SGRQ). Lower post-BD %pred FEV1 and, to a lesser extent, lower post-BD %pred FVC were significantly associated with ⩾1 physician-reported exacerbation at baseline or Year 1. This association was stronger in patients with COPD than in those with asthma. In a real-life setting, reduced lung function is consistently associated with symptoms in patients with asthma, COPD, or asthma + COPD. The relationship with exacerbations is stronger in COPD only than in asthma. clinicaltrials.gov identifier: NCT02760329 (www.clinicaltrials.gov).

Effects of low workload respiratory training with steam inhalation on lung function in stable asthma: A controlled clinical study.

To investigate effects of low workload respiratory muscle training (RMT) on respiratory muscle power and lung function in asthmatics, we recruited asthmatic persons who performed a 4-week training programme. The training included 20 daily ex- and inhalations with counter pressure 30% from the individual maximal expiratory pressure (MEP). Lung function was measured before and after the training programme and a follow-up period. The study also included several subjective endpoints for respiratory symptoms. A significant increase in a training group (n = 27) compared with a control group (n = 20) was seen in MEP (+12.4%, vs. +3.5%, p = 0.086), maximal inspiratory pressure (MIP) (+21.1% vs. +0.82%, p = 0.023), slow vital capacity (VC) (+3.7% vs. +1.5%, p = 0.023)and in forced expiratory time (FET, +15.5%, vs. -5.0%, p = 0.022). After being a control for group A, also group B performed similar RMT as group A. In the combined group (A and B, n = 47) MEP (11.3%, p = 0.003), MIP (19.73%, p < 0.001), VC (4.1%, p < 0.001)and FET (14.7%, p < 0.001) increased significantly from the baseline. Changes in other lung function variables were not indicative. On a scale of 1-5, the subjects perceived improvement in reduction of mucus secretion in the airways (median 3, p < 0.001), alleviation of coughing (median 3, p < 0.001)and reduction in dyspnoea (median 3, p < 0.001). As a conclusion, low workload respiratory training of 4 weeks improved respiratory muscle power and increased VC in patients with stable asthma.

TCN1 Expression Is Increased in Asthma

Introduction: Asthma is a chronic disease that affects populations worldwide. The purpose of this study was to investigate the expression of TCN1 in sputum and its correlation with inflammation and lung function in asthma. Methods: We recruited 141 subjects, detected TCN1 mRNA level by quantitative reverse transcription polymerase chain reaction, detected TCN1 protein expression by Western blot, detected TCN1 protein level by enzyme-linked immunosorbent assay, and analyzed the correlation between TCN1 and fraction of exhaled nitric oxide (FeNO), IgE, EOS%, lung functions, and some Th2 cytokines. The diagnostic value of TCN1 was evaluated by receiver operating characteristics curve. The expression of TCN1 was further confirmed by human bronchial epithelial cell in vitro. Results: Compared with the health group, the expression of TCN1 in induced sputum cells increased in asthma group and was correlated with FeNO, IgE, and EOS%. TCN1 level was also elevated in the induced sputum supernatant of asthma patients. The protein level of TCN1 in induced sputum supernatant was correlated with FeNO, IgE and PC-20, forced expiratory volume in the first second (FEV1)%pred, FEV1/FVC, and some cytokines (IL-4, IL-5, IL-10, IL-13, MUC5AC). TCN1 was also differentially expressed in patients with different severity of asthma. Four weeks after ICS treatment, the expression of TCN1 in induced sputum supernatant increased. In vitro, the protein level of TCN1 in human bronchial epithelial cells’ supernatant increased after stimulated with IL-4 and IL-13. Conclusion: The expression of TCN1 was increased in asthma patients’ sputum, and was positively correlated with some inflammatory markers, negatively correlated with lung function. TCN1 may be used as a potential biomarker for the diagnosis and treatment of asthma.

Genetic differences according to onset age and lung function in asthma: A cluster analysis.

The extent of differences between genetic risks associated with various asthma subtypes is still unknown. To better understand the heterogeneity of asthma, we employed an unsupervised method to identify genetic variants specifically associated with asthma subtypes. Our goal was to gain insight into the genetic basis of asthma. In this study, we utilized the UK Biobank dataset to select asthma patients (All asthma, n=50,517) and controls (n=283,410). We excluded 14,431 individuals who had no information on predicted values of forced expiratory volume in one second percent (FEV1%) and onset age, resulting in a final total of 36,086 asthma cases. We conducted k-means clustering based on asthma onset age and predicted FEV1% using these samples (n=36,086). Cluster-specific genome-wide association studies were then performed, and heritability was estimated via linkage disequilibrium score regression. To further investigate the pathophysiology, we conducted eQTL analysis with GTEx and gene-set enrichment analysis with FUMA. Clustering resulted in four distinct clusters: early onset asthmanormalLF (early onset with normal lung function, n=8172), early onset asthmareducedLF (early onset with reduced lung function, n=8925), late-onset asthmanormalLF (late-onset with normal lung function, n=12,481), and late-onset asthmareducedLF (late-onset with reduced lung function, n=6508). Our GWASs in four clusters and in All asthma sample identified 5 novel loci, 14 novel signals, and 51 cluster-specific signals. Among clusters, early onset asthmanormalLF and late-onset asthmareducedLF were the least correlated (rg =0.37). Early onset asthmareducedLF showed the highest heritability explained by common variants (h2 =0.212) and was associated with the largest number of variants (71 single nucleotide polymorphisms). Further, the pathway analysis conducted through eQTL and gene-set enrichment analysis showed that the worsening of symptoms in early onset asthma correlated with lymphocyte activation, pathogen recognition, cytokine receptor activation, and lymphocyte differentiation. Our findings suggest that early onset asthmareducedLF was the most genetically predisposed cluster, and that asthma clusters with reduced lung function were genetically distinct from clusters with normal lung function. Our study revealed the genetic variation between clusters that were segmented based on onset age and lung function, providing an important clue for the genetic mechanism of asthma heterogeneity.

Efficacy of Herbal Medicines on Lung Function in Asthma: a systematic review and meta-analysis of randomized controlled trials.

The present study was designed to conduct a comprehensive systematic review and meta-analysis to assess the efficacy of herbal medicines as add-on therapy on lung function in asthmatic patients. A comprehensive search of online databases was performed up to December 2021 to identify randomized controlled trials that used orally herbal preparations for asthma as add-on therapy. Studies were assessed for methodological quality using the Cochrane Collaboration's Risk of Bias tool. The main outcome was percent predicted value of forced expiratory volume (% predicted FEV1). Pooled weighted mean difference (WMD) estimate with corresponding 95% confidence interval (CI) was calculated using inverse-variance weights method while random effects meta-analysis was used, taking into account clinical and conceptual heterogeneity. As a result, 1,525 studies were identified. 169 studies were reviewed in-depth and 23 studies met our systematic review inclusion criteria. Finally, nine randomized controlled trials were included in the meta-analysis. Findings indicated that use of herbal medicines in patients with asthma significantly improved % predicted FEV1 (WMD 3.73, 95% CI 1.76-5.70), with no evidence for significant heterogeneity (p = 0.56 [Q statistic], I2 = 0.0%). In subgroup analysis by age, improvement in % predicted FEV1 was higher and significant in adults (WMD 5.16; 95% CI 2.68-7.63) compared to children (WMD = 1.27; 95% CI -1.98-4.51). Sensitivity analysis showed the significant effect of herbal medicine consumption on improving FEV1 was consistently (range of summary WMDs 3.27-4.59), indicating that the meta-analysis model was robust. There was no evidence of publication bias both visually and statistically. Findings support, the complementary use of herbal medicines resulted in significant improvement in the lung function compared to standard treatment in asthmatic patients with no considerable adverse events. This improvement is more likely to be observed amongst adults.

Epithelium-derived cystatin SN inhibits house dust mite protease activity in allergic asthma.

Allergen source-derived proteases are a critical factor in the formation and development of asthma. The cysteine protease activity of house dust mite (HDM) disrupts the epithelial barrier function. The expression of cystatin SN (CST1) is elevated in asthma epithelium. CST1 inhibits the cysteine protease activity. We aimed to elucidate the role of epithelium-derived CST1 in the development of asthma caused by HDM. CST1 protein levels in sputum supernatants and serum of patients with asthma and healthy volunteers were measured by ELISA. The ability of CST1 protein to suppress HDM-induced bronchial epithelial barrier function was examined in vitro. The effects of exogenous CST1 protein on abrogating HDM-induced epithelial barrier function and inflammation were examined in mice in vivo. CST1 protein levels were higher in sputum supernatants (142.4 ± 8.95 vs 38.87 ± 6.85 ng/mL, P < 0.0001) and serum (1129 ± 73.82 vs 703.1 ± 57.02 pg/mL, P = 0.0035) in patients with asthma than in healthy subjects. The levels were significantly higher in patients with not well- and very poorly controlled asthma than those with well-controlled asthma. Sputum and serum CST1 protein levels were negatively correlated with lung function in asthma. CST1 protein levels were significantly lower in the serum of HDM-specific IgE (sIgE)-positive asthmatics than in sIgE-negative asthmatics. The HDM-induced epithelial barrier function disruption was suppressed by recombinant human CST1 protein (rhCST1) in vitro and in vivo. Our data indicated that human CST1 protein suppresses asthma symptoms by protecting the asthmatic bronchial epithelial barrier through inhibiting allergenic protease activity. CST1 protein may serve as a potential biomarker for asthma control.

Can long term add-on doxycycline improve lung function in asthma: The result of an open prospective real-world observation

Background: The inhibition of matrix metalloproteinases and IgE could be a prospective target of treating inflammation and remodelling of asthma. Doxycycline, a known antibiotic may qualify for the job for having both the properties. Objective: To look for effect on long term add-on oral doxycycline in patients of asthma. Methods: In an open prospective, real-world observation, a cohort of asthmatics was given to choose treatment either with a “standard” therapy (long-acting β-2 agonist + inhaled corticosteroid) or with the same and add-on long term doxycycline orally. The changes in postbronchodilator FEV1, FEV1/FVC, and FEF25–75 were noted for comparison with repeat spirometry after nearly a year. Results: The two groups (standard therapy alone [n = 73] and standard therapy plus doxycycline [n = 72]) were similar (p &lt; 0.05) as regards to age and BMI, but the subjects opting for add-on doxycycline had significantly lower baseline postbronchodilator FEV1 (1.25 ± 0.50 and 1.66 ± 0.73 Litres; p &lt; 0.0001). Both the groups had received treatment for similar length of time (346.89 ± 269.61 and 335.82 ± 274.51 days, respectively). The add-on doxycycline group had a significant improvement in absolute value of postbronchodilator FEV1 (130 mL [p = 0.0000]), whereas the subjects on standard therapy alone showed a reduction (70 mL [p = 0.027]) compared to the baseline values. There was a parallel increase in FEV1/FVC (p &lt; 0.005) and FEF25-75 (p &lt; 0.0001) in the doxycycline-treated patients, suggesting an overall improvement in airflow limitations. Conclusion: The add-on oral doxycycline tolerated well on long term and resulted in a significant improvement in spirometric indices of airflow limitations in the asthmatics. The observation deserves further validation.

Severe asthma with fungal sensitization is associated with worse small airway dysfunction but similar symptom control

Severe asthma with fungal sensitization is associated with worse small airway dysfunction but similar symptom control

Iron status and its relation to lung function in pediatric asthmatics: a cross-sectional study

BackgroundAsthma and iron deficiency are common pediatric conditions. In addition, iron deficiency may affect spirometry results in asthmatic children. So, we aimed to assess the effect of ion status on lung function in childhood asthma.ResultsIn this cross-sectional study, fifty asthmatic pediatric patients aged from 6 to 16 years presented to our institute during the period from (June 2018 to December 2018) were enrolled. Asthmatic patients were classified according to their complete blood count and iron profile into 2 groups: group 1, asthmatic children without iron deficiency anemia (IDA); and group 2, asthmatic children with IDA. All patients underwent full history taking, clinical examination, laboratory investigations, asthma control test, and pulmonary function tests (PFTs). The study showed that PFTs’ parameters (forced expiratory volume in one second (FEV1) % of predicted, FEV1/forced vital capacity, and maximal mid expiratory flow (MMEF) 25–75% of predicted) were significantly lower among asthmatics with IDA (80.62 ± 18.13, 78.36 ± 11.22, 62.35 ± 26.67) than among asthmatics without IDA (93.45 ± 15.51, 87.68 ± 10.81, 82.10 ± 24.74), respectively (p =0.012, 0.006, 0.012). Also, poorly controlled asthma was significantly higher among asthmatics with IDA (p =0.001). In addition, there was a statistically significant positive correlation between forced spirometry parameters, hemoglobin, and ferritin level (p=0.012, 0.042). Moreover, there was a significant positive correlation between hemoglobin level and MMEF 25–75% of predicted (p=0.012).ConclusionsLower iron status negatively affects the lung function in asthmatic children with a more obstructive pattern among asthmatics with IDA.

Impact of repeated patient counseling using different pressurized metered-dose inhalers training devices on inhalation technique, lung function, and asthma control in adult asthmatics

BackgroundPressurized metered-dose inhalers (pMDIs) are among the most common devices that asthmatic patients use. The poor pMDI inhalation technique mostly results in poor lung deposition. The present work aimed to compare the impact of introducing two different training devices combined with their related smartphone applications on the proper performance of the inhalation technique and lung function in asthmatic adults.MethodsA total of 316 patients were allocated to 3 groups, 105 in the control group (normal patient education group), 104 in the group using the Clip-Tone device and its smartphone applications, and 107 in the group using the Flo-Tone and its smartphone applications. Each group had three visits. Their number of inhalation technique mistakes was recorded, their forced expiratory volume in the first second (FEV1) was measured, and an asthma control test (ACT) was given. Afterward, they had their allocated training. Differences in medians of outcomes among repeated visits per group and different groups per visit were measured. Finally, correlation statistics between FEV1% of predicted and the correct performance of inhalation technique (as a whole and as separate steps) per visit were conducted to study any associations if existed.ResultsIn the short term (after 2 visits), the Clip-Tone group showed significant superiority (p < 0.01) to both, the control and Flo-Tone groups, in terms of overall proper technique performance, and FEV1% of predicted. In the long term (after 3 visits), both interventions have shown significant superiority to the control in terms of correct inhalation technique performance (p < 0.05) and FEV1% of predicted (p < 0.01). None of them have shown significant superiority to each other. In terms of ACT scores, the Flo-Tone group showed significant improvement to both the control (p < 0.01) and the Clip-Tone (p < 0.05) groups in the second visit. In the third visit, both advancement counseling groups showed significant superiority to the control group (p < 0.01); However, the difference in medians between both Clip-Tone’s and Flo-Tone’s ACT scores disappeared. Weak, yet significant (− 0.146, p < 0.05) negative correlation existed between the number of mistakes in inhalation technique in the third visit and FEV1% of predicted. Correct performance of step 7 in the third visit showed a weak significant positive correlation (0.2, p < 0.01) with FEV1% of predicted.ConclusionIntroducing new training devices to the normal counseling that provides visual and audial feedback has shown that they could further enhance the inhalation technique performance and subsequently the lung function outcomes and asthma control of asthmatic patients. Yet, larger studies might be required to test the superiority of one to another.

Impact of acute temperature and air pollution exposures on adult lung function: A panel study of asthmatics.

BackgroundIndividuals with respiratory conditions, such as asthma, are particularly susceptible to adverse health effects associated with higher levels of ambient air pollution and temperature. This study evaluates whether hourly levels of fine particulate matter (PM2.5) and dry bulb globe temperature (DBGT) are associated with the lung function of adult participants with asthma.Methods and findingsGlobal positioning system (GPS) location, respiratory function (measured as forced expiratory volume at 1 second (FEV1)), and self-reports of asthma medication usage and symptoms were collected as part of the Exposure, Location, and Lung Function (ELF) study. Hourly ambient PM2.5 and DBGT exposures were estimated by integrating air quality and temperature public records with time-activity patterns using GPS coordinates for each participant (n = 35). The relationships between acute PM2.5, DBGT, rescue bronchodilator use, and lung function collected in one week periods and over two seasons (summer/winter) were analyzed by multivariate regression, using different exposure time frames.In separate models, increasing levels in PM2.5, but not DBGT, were associated with rescue bronchodilator use. Conversely DBGT, but not PM2.5, had a significant association with FEV1. When DBGT and PM2.5 exposures were placed in the same model, the strongest association between cumulative PM2.5 exposures and the use of rescue bronchodilator was identified at the 0–24 hours (OR = 1.030; 95% CI = 1.012–1.049; p-value = 0.001) and 0–48 hours (OR = 1.030; 95% CI = 1.013–1.057; p-value = 0.001) prior to lung function measure. Conversely, DBGT exposure at 0 hours (β = 3.257; SE = 0.879; p-value>0.001) and 0–6 hours (β = 2.885; SE = 0.903; p-value = 0.001) hours before a reading were associated with FEV1. No significant interactions between DBGT and PM2.5 were observed for rescue bronchodilator use or FEV1.ConclusionsShort-term increases in PM2.5 were associated with increased rescue bronchodilator use, while DBGT was associated with higher lung function (i.e. FEV1). Further studies are needed to continue to elucidate the mechanisms of acute exposure to PM2.5 and DBGT on lung function in asthmatics.

House Dust Mite Subcutaneous Immunotherapy and Lung Function Trajectory in Children and Adolescents with Asthma.

Background: Allergen-specific immunotherapy is currently the only disease-modifying treatment for allergic asthma, and it has been shown to improve control of asthma while reducing both drug use and asthma exacerbations. However, its effects on lung function—especially its long-term effects—remain controversial. We aimed to identify factors associated with a possible beneficial effect of allergen-specific immunotherapy on lung function in asthma by retrospectively evaluating the long-term changes in lung function in children with asthma who received house dust mite subcutaneous immunotherapy (HDM-SCIT). Methods: We enrolled children with asthma who had undergone HDM-SCIT for more than 1 year. Clinical information and lung function measurements were retrieved from the electronic chart system. To characterize the trajectory of lung function change, we performed linear regression analysis to evaluate the maximal expiratory flow at 50% of the forced vital capacity during two periods: before and during HDM-SCIT. Slopes from a least-squares regression line for the two periods, i.e., S1 before HDM-SCIT and S2 during HDM-SCIT, were compared. The subjects were then classified into two groups: an improving group (Group I) defined as S2 − S1 > 0, and a declining group (Group D) defined as S2 − S1 < 0. The clinical factors at the start of HDM-SCIT were compared between the two groups. Results: A total of 16 patients were analyzed. Eight patients were classified into each of Group I and Group D. The mean ages were 10.5 and 11.8 years, and the mean treatment periods were 4.1 and 3.9 years. Group I had a significantly lower blood eosinophil count and a significantly higher HDM-specific IgE level than Group D. Logistic regression showed a strong relationship between those two markers and the lung function trajectory. Conclusion: Control of the blood eosinophil count in highly HDM-sensitized patients may increase the beneficial effect of HDM-SCIT on lung function.