Lower Lung Function Research Articles

Obstructive sleep apnoea and lung function, and their association with nocturnal hypoxemia: results from the Swedish CArdioPulmonary bioimage Study (SCAPIS) – a cross-sectional study

Obstructive sleep apnoea (OSA) and its associations with lung function.BackgroundOSA is highly prevalent and characterised by abnormal respiration during sleep. This large, population-based study aimed to investigate the associations between OSA and lung function in subjects aged 50–64 years.MethodThe population-based Swedish CArdioPulmonary bioimage Study includes information on anthropometry, comorbidities and spirometry. The current analysis included data from three centres (Gothenburg, Umeå and Uppsala) on whole-night respiratory polygraphy as a meta-analysis examining the overall effect size of lung function on sleep apnoea severity, expressed as ß-coefficient after stratifying for sex and adjusting for age, waist circumference and smoking status.ResultsData from9016participants (54%women, age58±4 years, body mass index27±4 kg/m2) with sleep recordings of good quality were included in the final analysis. Forced expiratory volume during1 s(FEV1) (ß=−0.10 (95% CI −0.16 to −0.03)),forced vital capacity(FVC) (−0.15 (−0.21 to −0.10)) anddiffusion capacity for carbon monoxide(DLCO) (−0.08 (−0.10 to −0.05)) were all negatively associated with theoxygen desaturation index(ODI) and also with per cent of registration with nocturnal oxygen saturation<90% FVC(−0.44 (−0.87 to −0.01)), FEV1(−0.86 (−1.36 to −0.36)) and DLCO(−0.47 (−0.60 to −0.35)). Additionally, a positive association was observed between FEV1(0.13 (0.05 to 0.22)) and DLCO(0.07 (0.04 to 0.09)) with the mean nocturnal saturation. There was a negative association between DLCOandapnoea-hypopnoea index, AHI, (ß=−0.04 (95% CI−0.06 to −0.03)), while no associations were found between FEV1or FVC and AHI.ConclusionIn OSA, lower lung function is more distinctly associated with the nocturnal hypoxic burden than AHI. Potential lung function impairment should be investigated in OSA patients with a high ODI relative to AHI.

Long-Term Exposure to Nitrogen Dioxide and Ozone and Respiratory Health in Children.

Further evaluation of the impact of long-term exposure to the gaseous air pollutants nitrogen dioxide (NO2) and ozone (O3) on child lung function, and of NO2 or O3 on eosinophilic airway inflammation, is needed. To determine whether NO2 and O3 are associated with lung function and FeNO in children. We measured lung function (FEV1 and FVC) at mid-childhood (mean age 7.9 years, n=703), early teens (13.2 years, n=976), and mid-teen (17.6 years, n=624) study visits, and fractional exhaled nitric oxide (FeNO) at the early and mid-teen study visits in Project Viva, a cohort of mother-child pairs in the Boston, MA area. Long-term exposure to NO2 and O3 was estimated at home address using geospatial models. We examined associations of home address NO2 and O3 exposure and proximity to roadway with lung function and FeNO using linear regression models, adjusting for age, sex, height, weight, season, relative humidity, temperature, parental smoking, and measures of socioeconomic status. We examined for effect modification of the mid-teen associations by blood eosinophil level, physical activity, aeroallergen sensitization, and parental atopy. Median exposure to NO2 was 33.1 ppb (interquartile range [IQR] 10.4 ppb) and to O3 was 35.3 ppb (IQR 3.4) in the first year of life. Exposure to NO2 was associated with lower FEV1 and FVC across all age groups and exposure time intervals: e.g. an IQR increment of NO2 exposure from birth through the early teen visit was associated with 189.9 mL lower FEV1 (95% CI -273.3, -106.5) at the mid-teen visit. Lifetime NO2 exposure at was associated with higher FeNO at the early teen visit: e.g. 16.2% higher FeNO [95% CI 7.1-26.4%) per IQR of lifetime NO2 through the early teen visit. O3 exposure was not associated with lung function or FeNO. Aeroallergen sensitization (measured in a subset of participants) modified associations of NO2 and O3 with FeNO. Exposure to NO2 was associated with lower lung function and higher FeNO among generally healthy children and teenagers. As NO2 exposure levels were within the annual EPA standard, these findings suggest a need to reduce exposure to this pollutant to optimize child respiratory health.

Low Lung Function Is Associated with High Population Attributable Fraction for Cardiovascular Mortality.

Chronic lung diseases are associated with increased risk of mortality due to coronary heart disease (CHD). Nonetheless, the population attributable fraction (PAF) of lung function impairment relative to other established cardiovascular risk factors is unclear. To evaluate the PAF of low lung function for CHD mortality Methods: We harmonized and pooled lung function and clinical data across 8 US general population cohorts. Impaired lung function was defined as FEV1 and/or FVC ≤95% predicted on baseline spirometry. The association between CHD mortality and risk factors was assessed using cause-specific proportional hazards and Fine-Gray proportional subdistribution hazards models, treating non-CHD mortality as a competing risk. Models were adjusted for lung function as well as age, sex, race/ethnicity, educational attainment, body mass index, smoking status, pack-years of smoking, diabetes mellitus, HDL, and high LDL (≥130 mg/dl). PAF was calculated as the relative change in the average absolute risk of ten-year CHD mortality by elimination of lung function lower than 95% predicted. Among 35143 participants, 1844 of 13174 (14.0%) deaths were due to CHD. Compared to FEV1pp >95%, the sub-distribution adjusted hazards ratio (95%CI) for low FEV1pp was 1.30 (1.18-1.44). The PAF for FEV1pp≤95% was 12%, ranking low FEV1 third in the list of PAF for CHD mortality, after hypertension and diabetes. Low FEV1pp ranked second in the subgroup of active smokers (PAF 14%), after hypertension. Low lung function, even in the range considered clinically normal, ranks high in the list of attributable risk factors for CHD mortality and should be considered in cardiovascular risk stratification.

The prevalence of respiratory symptoms and diseases and declined lung function among foundry workers.

Foundry workers are occupationally exposed to a variety of inhalable chemical substances. Occupational exposure to vapors, gases, dusts, and fumes can lead to adverse health effects on the respiratory system and cause chronic respiratory diseases, such as interstitial lung diseases (ILDs), chronic obstructive lung disease (COPD), chronic bronchitis, and emphysema. Research on respiratory symptoms, diseases, and lung function in foundry workers over the past few decades has been limited. The aim of this cross-sectional study was to assess the prevalence of respiratory symptoms and diseases and declined lung function of current foundry workers, ex-foundry workers, and unexposed controls. We assessed respiratory symptoms, diseases, and lung function among 335 current foundry workers, 64 ex-foundry workers, and 161 unexposed controls. The cumulative dust exposure (mg-y) of each participant was calculated, and the median cumulative dust exposure according to the main places of exposure was determined. A higher prevalence of chronic bronchitis, as reported in a questionnaire, was found among current and ex-foundry workers compared to unexposed controls, even after adjusting for pack-years of smoking (p = 0.009). Additionally, cough and wheezing in adulthood without respiratory infection, and chronic rhinitis symptoms were more common among current and ex-foundry workers compared to unexposed controls. These differences remained significant even after adjusting for pack-years of smoking and body mass index (BMI) (p = 0.007 and p < 0.001, respectively). Impaired lung function was more prevalent among both ex-foundry workers (29.7%) and current foundry workers (15.5%) compared to the unexposed controls (8.7%), with the difference remaining significant even after adjusting for the pack-years of smoking and BMI (p = 0.009). According to the questionnaire, the number of physician-diagnosed cases of chronic obstructive pulmonary disease (COPD) or chronic bronchitis was unexpectedly low compared to the indications from the symptom questionnaire and lung function test results, suggesting a potential underdiagnosis. The prevalence of silicosis was low (0.8%) among current and ex-foundry workers. Respiratory symptoms are common among foundry workers. Current and ex-foundry workers exhibited lower lung function in spirometry compared to unexposed controls. There is a potential underdiagnosis of COPD and chronic bronchitis among foundry workers.

Comparison of Longitudinal Outcomes in Children with Primary Ciliary Dyskinesia and Cystic Fibrosis.

Primary ciliary dyskinesia (PCD) and cystic fibrosis (CF) are both genetic diseases of mucociliary clearance resulting in progressive lung disease with onset in early life. PCD is often considered to be milder in childhood than CF, based on minimal evidence. Similar to CF, genotype-phenotype associations exist in PCD: pathogenic variants in CCDC39 and CCDC40, causing inner dynein arm/microtubular defects (IDA/MTD) are associated with more severe disease. To compare longitudinal outcomes in matched children with PCD and CF. We hypothesized that children with PCD with IDA/MTD defects would have lower lung function but better nutritional indices than matched children with CF with minimal function genotypes (i.e., those associated with pancreatic insufficiency). Children with PCD enrolled in a prospective, multicenter, observational study were matched with CF patients from the CF Foundation Patient Registry by birth cohort, age, sex, race/ethnicity and year of study visit. The association of disease group overall and by severity class (PCD-IDA/MTD versus all other defects and CF-minimal versus residual function) with longitudinal outcomes up to age 17 was evaluated with cubic spline mixed effects models. Groups included 136 children with PCD (40 IDA/MTD, 96 other) and 476 with CF (446 minimal function, 30 residual function). Below age 14, the PCD group had similar or lower estimated mean FEV1 % predicted compared to CF (e.g., at age 10, -5.4 % predicted lower (95% CI: -7.7, -3.1)). Compared to the CF-minimal function (pancreatic insufficient) group, the PCD-IDA/MTD group had similar BMI; estimated mean FEV1 % predicted was significantly lower by age 10 (mean difference -10.6% (95% CI: -14.7, -6.4), increasing to -15.7% (95% CI: -20.3, -11.2) at age 14. The CF cohort had increased prevalence of Pseudomonas aeruginosa cultured on one or more occasions compared to children with PCD (67% vs 27%, p<0.001); there was no difference in prevalence of P. aeruginosa between children with PCD-IDA/MTD and PCD-other. In childhood, average lung function abnormalities in PCD are not milder than CF, particularly for those with IDA/MTD ciliary defects. New guidelines and treatments to improve outcomes in PCD are urgently needed.

Long-term respiratory consequences of prematurity.

Approximately 10% of all children worldwide are born preterm and respiratory consequences are amongst the most common sequelae of preterm birth. Except for a higher prevalence of respiratory symptoms and hospital admissions, preterm birth is associated with lower lung function that may track into adulthood. Lung function impairment is not restricted to extreme or very preterm-born subjects as also children born moderate-late preterm have lower Z-scores for lung function. Given the heterogeneity of prematurity-associated lung disease, phenotype-based, multidisciplinary management is needed to improve respiratory health in preterm-born subjects.

Correlation analysis of serum Rac1 level with asthma control, airway inflammatory response and lung function in asthmatic children

ObjectiveTo investigate the correlation between serum Rac1 enzyme (Rac1) level with asthma control, airway inflammatory response and lung function in asthmatic children.MethodsA retrospective analysis was performed on 79 children with asthma who were diagnosed and treated in our hospital from June 2020 to January 2023. According to the severity of the disease, the children were divided into mild group (25 cases), moderate group (30 cases) and severe group (24 cases). 36 healthy children who underwent physical examination at the same period in our hospital were selected as the control group. The state of an illness, control level, serum mRNA Rac1, inflammatory factors, and lung function of the children in two groups were compared between the control group and the observation group.ResultsThe Rac1 mRNA levels, forced vital capacity (FVC), forced expiratory volume in one second/FVC (FEV1/FVC), peak expiratory flow (PEF), and maximum mid-expiratory flow (MMEF) in the observation group were significantly lower than these in the control group (P < 0.05). The tumor necrosis factor-alpha (TNF-α), interleukin-5 (IL-5), IL-6, and IL-33 in the observation group were markedly higher than these in the control group (P < 0.05). As the state of an illness worsened, the Rac1 mRNA levels, FVC, FEV1/FVC, PEF, and MMEF gradually reduced (P < 0.05), while the levels of TNF-α, IL-5, IL-6, and IL-33 increased (P < 0.05). As the degree of disease control improved, the Rac1 mRNA levels, FVC, FEV1/FVC, PEF, and MMEF gradually elevated (P < 0.05), and the levels of TNF- α, IL-5, IL-6, and IL-33 showed the opposite trend (P < 0.05). Rac1 was negatively related to the levels of TNF-α, IL-5, IL-6 and IL-33 (P < 0.05), and positively to the levels of FVC, FEV1/FVC, PEF and MMEF (P < 0.001). Rac1 mRNA levels, FVC, FEV1/FVC, PEF and MMEF were protective factors, while TNF-α, IL-5, IL-6 and IL-33 were risk factors for the prognosis of children with asthma (P < 0.05).ConclusionChildren with asthma have obviously lower serum Rac1 mRNA levels, higher inflammatory factor levels and lower lung function. Serum Rac1 mRNA level may be associated with better asthma control, lower airway inflammatory response, better lung function and lower disease severity. It has important reference value for the evaluation of the state of an illness, efficacy and prognosis of children with bronchial asthma.

Effect of low climate impact vs. high climate impact inhalers for patients with asthma and COPD-a nationwide cohort analysis

BackgroundChronic obstructive pulmonary disease (COPD) and asthma can be treated with inhaled corticosteroids (ICS) delivered by low climate impact inhalers (dry powder inhalers) or high climate impact inhalers (pressurized metered-dose inhalers containing potent greenhouse gasses). ICS delivered with greenhouse gasses is prescribed ubiquitously and frequent despite limited evidence of superior effect. Our aim was to examine the beneficial and harmful events of ICS delivered by low and high climate impact inhalers in patients with asthma and COPD.MethodsNationwide retrospective cohort study of Danish outpatients with asthma and COPD treated with ICS delivered by low and high climate impact inhalers. Patients were propensity score matched by the following variables; age, gender, tobacco exposure, exacerbations, dyspnoea, body mass index, pulmonary function, ICS dose and entry year. The primary outcome was a composite of hospitalisation with exacerbations and all-cause mortality analysed by Cox proportional hazards regression.ResultsOf the 10,947 patients with asthma and COPD who collected ICS by low or high climate impact inhalers, 2,535 + 2,535 patients were propensity score matched to form the population for the primary analysis. We found no association between high climate impact inhalers and risk of exacerbations requiring hospitalization and all-cause mortality (HR 1.02, CI 0.92–1.12, p = 0.77), nor on pneumonia, exacerbations requiring hospitalization, all-cause mortality, or all-cause admissions. Delivery with high climate impact inhalers was associated with a slightly increased risk of exacerbations not requiring hospitalization (HR 1.10, CI 1.01–1.21, p = 0.03). Even with low lung function there was no sign of a superior effect of high climate impact inhalers.ConclusionLow climate impact inhalers were not inferior to high climate impact inhalers for any risk analysed in patients with asthma and COPD.

Long-Term Outcomes of Allergic Bronchopulmonary Aspergillosis and Aspergillus Colonization in Children and Adolescents with Cystic Fibrosis.

Observational studies indicate that Aspergillus colonization and allergic bronchopulmonary aspergillosis (ABPA) in people with cystic fibrosis (CF) are associated with poorer lung health and increased disease severity. We performed a longitudinal observational cohort study to analyse long-term outcomes of Aspergillus colonization and ABPA in children with CF. Anonymised UK CF Registry data from 2009 to 2019 for patients aged 8-17 years in 2009-2010 were collected. For the baseline cohort analysis, patients were classified based on the presence of Aspergillus colonization and ABPA in 2009 and/or 2010. For the longitudinal analysis, patients were categorised according to annual Aspergillus colonization and ABPA status. Comparisons made were (1) Aspergillus positive vs. negative; (2) excluding those with ABPA: Aspergillus positive vs. negative; and (3) ABPA positive vs. negative. Primary outcome was percentage predicted FEV1 decline and secondary outcomes included BMI decline, mortality, lung transplant, and IV antibiotic use. Of the 1675 children, 263 had Aspergillus colonization in the baseline cohort, 260 were diagnosed with ABPA, and 80 had both. Baseline cohort analysis showed significantly lower lung function (p < 0.0001) and increased antibiotic treatment (p < 0.001) in those with Aspergillus colonization and in those with ABPA. Longitudinal analysis showed ABPA was associated with increased decline in lung function (p < 0.00001) and BMI (p < 0.00001). Aspergillus colonization was associated with increased decline in BMI (p = 0.005) but not lung function (p = 0.30). ABPA was associated with increased decline in long-term lung function and BMI in children and young people with CF. Aspergillus colonization was associated with lower lung function at baseline, but no increased rate of decline was observed long-term.

Association of blood inflammatory phenotypes and asthma burden in children with moderate-to-severe asthma

BackgroundUnderlying immunological mechanisms in children with moderate-to-severe asthma are complex and unclear. We aimed to investigate the association between blood inflammatory parameters and asthma burden in children with moderate-to-severe asthma.MethodsBlood inflammatory parameters (eosinophil(E) and neutrophil(N) counts and inflammatory mediators using multiplex immunoassay technology) were measured in children (6–17 years) with moderate-to-severe asthma from SysPharmPediA cohort across four European countries. Based upon low(L)/high(H) blood(B) eosinophil (LBE/HBE: &lt;/≥0.3×109/L, respectively) and neutrophil counts (LBN/HBN: &lt;/≥4×109/L, respectively), mixed(HBE-HBN), eosinophilic(HBE-LBN), neutrophilic(LBE-HBN), and paucigranulocytic(LBE-LBN) phenotypes were defined. Inflammatory mediator profiles and burden of disease (asthma control status, exacerbations and school days missed in the past year) were compared between phenotypes using adjusted logistic regression models.ResultsAmong 126 included children (41% girls and mean(sd) age of 11.94(2.76)), 22%, 44%, 11%, and 23% were classified as mixed, eosinophilic, neutrophilic, and paucigranulocytic phenotypes respectively. Neutrophilic children had lowest lung function (FEV1%predicted pre-salbutamol) compared to other groups. Children with mixed asthma were most often uncontrolled and had highest asthma-related school absence in the past year. Interleukin-6(IL-6) and matrix metalloproteinase-9(MMP-9) levels were significantly higher in patients with mixed or neutrophilic asthma, while tissue inhibitor of metalloproteinase-2(TIMP-2) was lower in patients with neutrophilic asthma compared to eosinophilic or paucigranulocytic asthma. Interleukin-5(IL-5) was increased in eosinophilic group compared to neutrophilic and paucigranulocytic groups, irrespective of the chosen cut-off for eosinophilia.ConclusionDifferences in asthma burden-related clinical expression and distinct blood inflammatory mediator profiles were found between phenotypes, highlighting implications for optimizing personalized treatment and management strategies in children with moderate-to-severe asthma.

Clinical and inflammatory features of traffic-related diesel exposure in children with asthma

BackgroundEpidemiologic studies have revealed associations between traffic-related pollutants such as diesel particulate matter (PM) and asthma outcomes in children, but the inflammatory features associated with diesel PM exposure in children with asthma are not understood. ObjectiveTo evaluate symptoms, exacerbations, and lung function measures in children with uncontrolled asthma and their associations with residential proximity to major roadways and to determine associations between diesel PM exposure and systemic inflammatory cytokines, circulating markers of T-cell activation and exhaustion, and metabolomic features using biomarker studies. MethodsChildren 5 to 17 years of age with physician-diagnosed, uncontrolled asthma despite treatment with an asthma controller medication completed a research visit involving questionnaires, lung function testing, and venipuncture for biomarker studies. Geocoding was performed to quantify residential proximity to major roadways and pollutant exposure. ResultsA total of 447 children with uncontrolled asthma were enrolled. Children living closer to highly trafficked roadways were more disadvantaged and had more exposure to diesel PM, more exacerbations prompting an emergency department visit, and lower lung function measures. Children with the highest diesel PM exposure, compared with children with the lowest diesel PM exposure, also had blunted cytokine secretion and evidence of T-cell exhaustion, including disturbances in several metabolites associated with glutathione formation and oxidative stress. ConclusionTraffic-related diesel PM exposure in children with poorly controlled asthma is associated with poorer clinical outcomes and unique patterns of inflammation and oxidative stress. These findings argue for continued mitigation efforts to improve traffic-related air quality and health equity in children with asthma.

Blood lipid profiles as a prognostic biomarker in idiopathic pulmonary fibrosis

BackgroundDysregulation of lipid metabolism is implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF). However, the association between the blood lipid profiles and the prognosis of IPF is not well defined. We aimed to identify the impacts of lipid profiles on prognosis in patients with IPF.MethodsClinical data of 371 patients with IPF (145 and 226 in the derivation and validation cohorts, respectively), including serum lipid profiles (total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, apolipoprotein A-I [Apo A-I], and apolipoprotein B), were retrospectively collected. The association with mortality was analyzed using the Cox proportional hazard model.ResultsIn the derivation cohort, the mean age was 67.5 years, 86.2% were men, and 30.3% died during the follow-up (median: 18.0 months). Non-survivors showed lower lung function and greater gender-age-physiology scores than survivors. Among the serum lipid profiles, the levels of triglyceride and Apo A-I were significantly lower in non-survivors than in survivors. In the multivariate Cox analysis, low Apo A-I levels (< 140 mg/dL) were independently associated with the risk of mortality (hazard ratio 3.910, 95% confidence interval 1.170-13.069; P = 0.027), when adjusted for smoking history, body mass index, GAP score, and antifibrotic agent use. In both derivation and validation cohorts, patients with low Apo A-I levels (< 140 mg/dL) had worse survival (median survival: [derivation] 34.0 months vs. not reached, P = 0.003; [validation] 40.0 vs. 53.0 months, P = 0.027) than those with high Apo A-I levels in the Kaplan–Meier survival analysis.ConclusionsOur results indicate that low serum Apo A-1 levels are an independent predictor of mortality in patients with IPF, suggesting the utility of serum Apo A-I as a prognostic biomarker in IPF.

Treatment of small as well as large declines in lung function enhances recovery to baseline in people with CF.

The benefit of antibiotic treatment of acute drops in FEV1 percent predicted (FEV1pp) has been clearly established, but data from the early 2000s showed inconsistent treatment. Further, there is no empirical evidence for what magnitude of drop is clinically significant. We used data from the CF Foundation Patient Registry (CFFPR) from 2016 to 2019 to determine the association between treatment (any IV antibiotics, only oral or newly prescribed inhaled antibiotics, or no antibiotic therapy) following a decline of ≥5% from baseline FEV1pp and return to 100% baseline FEV1pp days using multivariable logistic regression including an interaction between the magnitude of decline and treatment category. Overall, 16,495 PWCF had a decline: 16.5% were treated with IV antibiotics, 25.0% non-IV antibiotics, and 58.5% received no antibiotics. Antibiotic treatment was more likely for those with lower lung function, history of a positive PA culture, older age and larger FEV1 decline (p < 0.001). Treatment with IV antibiotics or oral/inhaled antibiotics was associated with a higher odds of recovery to baseline compared to no treatment across all levels of decline, including declines of 5%-10%. A large proportion of acute drops in FEV1pp continue to be untreated, especially in younger patients and those with higher baseline lung function. Acute drops as small as 5% predicted are less likely to be recovered if antibiotic treatment is not prescribed. These findings suggest the need for more aggressive antimicrobial treatment of acute drops in FEV1, including those of a magnitude previously believed to be associated with self-recovery.

Characteristics of Adults With Severe Asthma in Childhood: A 60-Year Follow-Up Study

BackgroundChildhood asthma is a prevalent condition with potential impact on adult life. Research QuestionIn a 60-year follow-up study of adults with a history of severe childhood asthma, what are the potential differences in characteristics between individuals with persistent asthma and asthma remission in adulthood? Study Design and MethodsDanish adults with a history of childhood asthma and a 4-month stay in at an asthma care facility in Kongsberg, Norway (1950-1979) in childhood were included. Recruitment was done through social media and personal invitation letters. Participants completed questionnaires and underwent spirometry, bronchial provocation, and bronchodilator reversibility and blood tests. Asthma remission was defined as no use of asthma medication and no asthma symptoms within the past 12 months with the remaining participants being classified as having current asthma. ResultsAmong 1394 eligible participants, 232 completed the follow-up. Ninety percent had current asthma, of whom 26% reported exacerbations in the past year. Only 16% of all the participants were managed in secondary care. Common comorbidities were allergic rhinitis (60%), hypertension (21%), eczema (16%), and cataract (8%). Compared to participants in remission, participants with persistent asthma had higher total immunoglobulin E (p=0.03), and both lower FEV1%pred (p=0.03), and FEV1/FVC ratio (p<0.001), as well as numerically higher fractional exhaled nitric oxide and blood eosinophil count. InterpretationOur 60-year follow-up study of adults with a history of severe childhood asthma revealed that nine out of ten still had current asthma. Persistent asthma was associated with lower lung function and higher levels of type 2 inflammatory biomarkers compared to those with asthma remission.

Comprehensive analysis of environmental exposure to hazardous trace elements and lung function: a national cross-sectional study

BackgroundThere is growing interest in the joint effects of hazardous trace elements (HTEs) on lung function deficits, but the data are limited. This is a critical research gap given increased...

Association between low lung function and the increased risk of age-related macular degeneration: A population-based prospective cohort study

Association between low lung function and the increased risk of age-related macular degeneration: A population-based prospective cohort study

Metabolomics analysis of bronchoalveolar lavage fluid predicts unique features of the lower airway in pediatric cystic fibrosis

BackgroundProgressive, obstructive lung disease resulting from chronic infection and inflammation is the leading cause of morbidity and mortality in persons with cystic fibrosis (PWCF). Metabolomics and next -generation sequencing (NGS) of airway secretions can allow for better understanding of cystic fibrosis (CF) pathophysiology. In this study, global metabolomic profiling on bronchoalveolar lavage fluid (BALF) obtained from pediatric PWCF and disease controls (DCs) was performed and compared to lower airway microbiota, inflammation, and lung function. MethodsBALF was collected from children undergoing flexible bronchoscopies for clinical indications. Metabolomic profiling was performed using a platform developed by Metabolon Inc. Total bacterial load (TBL) was measured using quantitative polymerase chain reaction (qPCR), and bacterial communities were characterized using 16S ribosomal RNA (rRNA) sequencing. Random Forest Analysis (RFA), principal component analysis (PCA), and hierarchical clustering analysis (HCA) were performed. ResultsOne hundred ninety-five BALF samples were analyzed, 142 (73 %) from PWCF. Most metabolites (425/665) and summed categories (7/9) were significantly increased in PWCF. PCA of the metabolomic data revealed CF BALF exhibited more dispersed clustering compared to DC BALF. Higher metabolite concentrations correlated with increased inflammation, increased abundance of Staphylococcus, and decreased lung function. ConclusionsThe lower airway metabolome of PWCF was defined by a complex expansion of metabolomic activity. These findings could be attributed to heightened inflammation in PWCF and aspects of the CF airway polymicrobial ecology. CF-specific metabolomic features are associated with the unique underlying biology of the CF airway.

Vitamin D Status and Longitudinal Changes in Body Composition in Patients with Chronic Obstructive Pulmonary Disease - A Prospective Observational Study.

Alterations in body weight and composition are common in patients with chronic obstructive pulmonary disease (COPD) and are independent predictors for morbidity and mortality. Low vitamin D status is also more prevalent in patients with COPD compared to controls and has been related to lower lung function, muscle atrophy and impaired musculoskeletal function. This study aimed to evaluate the association between vitamin D levels and status with body composition (BC), as well as with its changes over time. Patients with COPD and controls without COPD, participating in the Individualized COPD Evaluation in relation to Ageing (ICE-Age) study, a prospective observational study, were included. Plasma 25-hydroxyvitamin D (25(OH)D) was measured at baseline and BC was measured by dual-energy X-ray absorptiometry scan, at baseline and after two years of follow-up. Multiple linear regression analyses were performed to assess the relationships between 25(OH)D (nmol/l) and longitudinal changes in BMI, fat-free mass index (FFMI), fat mas index (FMI) and bone mineral density (BMD). A total of 192 patients with COPD (57% males, mean ± SD age, 62 ± 7, FEV1, 49 ± 16% predicted) and 199 controls (45% males, mean ± SD age 61 ± 7) were included in this study. Vitamin D levels were significantly lower in patients with COPD (64 ± 26 nmol/L, 95% CI 60-68 nmol/L versus 75 ± 25 nmol/L, 95% CI 72-79 nmol/L) compared to controls. Both patients and controls presented a significant decline in FFMI and T-score hip, but vitamin D level or status did not determine differences in BC or changes in BC over time in either COPD or controls. Vitamin D status was not associated with BC or longitudinal changes in BC. However, vitamin D insufficiency and low BMD were more prevalent in patients with COPD compared to controls.

Investigation of lactotransferrin messenger RNA expression levels as an anti–type 2 asthma biomarker

Lactotransferrin (LTF) has an immunomodulatory function, and its expression levels are associated with asthma susceptibility. We sought to investigate LTF messenger RNA (mRNA) expression levels in human bronchial epithelial cells (BECs) as an anti-type 2 (T2) asthma biomarker. Association analyses between LTF mRNA expression levels in BECs and asthma-related phenotypes were performed in the Severe Asthma Research Program (SARP) cross-sectional (n= 155) and longitudinal (n= 156) cohorts using a generalized linear model. Correlation analyses of mRNA expression levels between LTF and all other genes were performed by Spearman correlation. Low LTF mRNA expression levels were associated with asthma susceptibility and severity (P< .025), retrospective andprospective asthma exacerbations, and low lung function (P< 8.3×10-3). Low LTF mRNA expression levels were associated with high airway T2 inflammation biomarkers (sputum eosinophils and fractional exhaled nitric oxide; P<8.3×10-3) but were not associated with blood eosinophils or total serum IgE. LTF mRNA expression levels were negatively correlated with expression levels of TH2 or asthma-associated genes (POSTN, NOS2, and MUC5AC) and eosinophil-related genes (IL1RL1, CCL26, and IKZF2) and positively correlated with expression levels of TH1 and inflammation genes (IL12A, MUC5B, and CC16) and TH17-driven cytokines or chemokines for neutrophils (CXCL1,CXCL6, and CSF3) (P< 3.5×10-6). Low LTF mRNA expression levels in BECs are associated with asthma susceptibility, severity, and exacerbations through upregulation of airway T2 inflammation. LTF is a potential anti-T2 biomarker, and its expression levels may help determine the balance of eosinophilic and neutrophilic asthma.

Application of the Lancet Commission COPD classification to COPD Cohort Population in South Korea

The Lancet Commissions on COPD recommended a new classification based on five main risk factors.Patients with COPD were prospectively enrolled in a Korean COPD subgroup study cohort between April 2012 and June 2022. Patients were classified according to the etiologies (Type 1: Genetically determined (COPD-G), Type 2: Abnormal lung development (COPD-D), Type 3: Infections (COPD-I), Type 4: Cigarette smoking (COPD-C), Type 5: Biomass and pollution (COPD-P)).The database enrolled 3476 patients. Among 3392 patients, 52 (2 %), 1339 (39 %), 2930 (86 %), and 2221 (65 %) were compatible with type 2 (COPD-D), 3 (COPD-I), 4 (COPD-C), and 5 (COPD-P), respectively. Most patients (71 %, 2405) had multiple risk factors contributing to their COPD. However, 93, 712, and 182 patients had only type 3 (COPD-I), 4 (COPD-C), and 5 (COPD-P), respectively. Type 3 (COPD-I) only patients were significantly younger, more often female, and had lower lung function. Both the rate and frequency of severe exacerbations were significantly higher in type 3 (COPD-I) only patients (p = 0.038 and p = 0.048, respectively). Compared with type 5 (COPD-P) only, type 3 (COPD-I) only was significantly associated with the risk of severe exacerbation (Odds ratio, 5.7 [95 % CI, 1.0–32.4]; P = 0.049, incident rate ratio, 8.7 [95 % CI, 1.7–44.0]; P = 0.009).Many patients were affected by multiple factors. Therefore, it is important to consider not only smoking history, but also other potential risk factors when evaluating patients with COPD. Further research is needed to explore the implications of this new COPD classification system for clinical practice and treatment strategies.