Socioeconomic differences in limited lung function: a cross-sectional study of middle-aged and older adults in Germany.

BACKGROUND: Limited lung function represents a serious health impairment. However, studies investigating social inequalities in limited lung function are rare. Thus, the current study investigates which socioeconomic groups are the most affected by overall limited lung function and severely limited lung function. METHODS: Data from the population-based German Aging Survey were used (N = 4472), with participants being 40 + years old. Lung function was assessed by the peak flow test. Education, income, and occupational prestige were used as socioeconomic indicators. RESULTS: We found that overall limited lung function was highly prevalent across the whole sample, with about 33% (Women: 35%; Men: 30%) having overall limited lung function and 8% (Women: 7%; Men: 8%) having severely limited lung function. Socioeconomic differences in limited lung function emerged for all three indicators, education, income, and occupational prestige, in both men and women in single effect analyses. These differences persisted for occupational prestige and income when controlling for all indicators simultaneously. CONCLUSIONS: Thus, overall and severely limited lung function are highly prevalent health conditions. Men and women with a low occupational position and those with low income are the most affected. Socioeconomic indicators cannot be used interchangeably when studying health inequalities in lung functioning. Occupational hazards and physical working conditions are likely to constitute major risks of health inequalities in limited lung functioning and should be investigated as such by future studies.

Is there a correlation between the changes in airway inflammation and the changes in respiratory mechanics after vaping in patients with asthma?

BACKGROUND: Electronic cigarettes (ECs) have been promoted as alternatives to traditional cigarettes. AIM: To investigate ECs' effects on respiratory system, especially in patients with respiratory diseases. METHODS: We randomly selected 25 smokers with stable moderate asthma and matched them with 25 healthy smokers. All were subjucted to pulmonary function tests (PFTs), impulse oscillometry (IOS), fraction exhaled Nitric Oxide (FeNO), exhaled breathe condensate (EBC) and biomarker measurements before and after vaping one nicotine-containing EC. RESULTS: The increase in FeNO 30 minutes after EC, reflecting airway inflammation, significantly correlated with increase of residual volume (RV), total lung capacity, respiratory impedance at 5 Hz (Z5Hz) and respiratory resistance at 5 and 20 Hz (R5Hz and R20Hz). No significant correlations were found between EBC biomarkers' changes and respiratory mechanics. CONCLUSION: This is the first study demonstrating that the changes in airway inflammation caused by EC have direct effects in respiratory mechanics of asthmatic patients.

The mediating role of air pollutants in the association between education and lung function among the elderly, the HAPIEE study.

BACKGROUND: Chronic exposure to air pollutants harms human health, and at a geographical level, concentrations of air pollutants are often associated with socioeconomic disadvantage. OBJECTIVES: The aim of this study was to investigate the effects of educational attainment and air pollution on lung function in older adults, and whether air pollution may mediate the effect of education. METHODS: The study included 6381 individuals (mean age 58.24 ±â€¯7.14 years) who participated in the Czech HAPPIE (Health, Alcohol, and Psychosocial Factors in Eastern Europe) study. Participants' residential addresses were linked to air pollution data, including mean exposures to PM10 (particulate matter of aerodynamic diameter below 10 µm) and NO2 (nitrogen dioxide). We used path analysis to link educational attainment and air pollutants to a standardized measure of the Forced Expiratory Volume in the first second (FEV1). RESULTS: Higher levels of participants' education were associated with lower exposures to PM10 and NO2. Individuals with tertiary education had higher standardized FEV1 than individuals with primary education (88 % vs 95 %). Path analysis revealed a direct positive effect of education on FEV1, while about 12 % of the relationship between education and lung function was mediated by PM10 and NO2. CONCLUSIONS: Education (typically completed at young ages) appeared to have a protective effect on lung function later in life, and a small part of this effect was mediated by air pollution.

Association of preserved ratio impaired spirometry with mortality and cardiovascular diseases: a systematic review and meta-analysis.

BACKGROUND: Preserved ratio impaired spirometry (PRISm) is a type of abnormal lung function. PRISm and mortality have been explored in several studies, but a comprehensive evaluation of the associations is limited. The current study aims to conduct a systematic review and meta-analysis in order to investigate the mortality and cardiovascular diseases in patients with PRISm. METHODS: PubMed, Embase, and Web of Science databases, as well as gray literature sources, were searched for relevant studies published up to 7 September 2023 without language restrictions. This review included all published observational cohort studies that investigated the association of PRISm with mortality in the general population, as well as subgroup analyses in smokers and pre-bronchodilation spirometry studies. The outcomes of interest were all-cause mortality, cardiovascular mortality, and respiratory-related mortality. The Newcastle-Ottawa scale assessed study quality. Sensitivity and subgroup analyses explored heterogeneity and robustness. Publication bias was assessed with Egger's and Begg's tests. RESULTS: Overall, eight studies were included in this meta-analysis. The pooled HR was 1.60 (95% CI, 1.48-1.74) for all-cause mortality, 1.68 (95% CI, 1.46-1.94) for CVD mortality, and 3.09 (95% CI, 1.42-6.71) for respiratory-related mortality in PRISm group compared to normal group. In the subgroup analysis, participants with PRISm had a higher effect (HR, 2.11; 95% CI, 1.74-2.54) on all-cause mortality among smokers relative to participants with normal spirometry. Furthermore, the association between PRISm and mortality risk was consistent across several sensitivity analyses. CONCLUSIONS: People with PRISm were associated with an increased risk of all-cause mortality, CVD mortality, and respiratory-related mortality as compared to those with normal lung function in the general population. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42023426872.

Expiratory Venous Volume and Arterial Tortuosity are Associated with Disease Severity and Mortality Risk in Patients with COPD: Results from COSYCONET.

Purpose: The aim of this study was to evaluate the association between computed tomography (CT) quantitative pulmonary vessel morphology and lung function, disease severity, and mortality risk in patients with chronic obstructive pulmonary disease (COPD). Patients and Methods: Participants of the prospective nationwide COSYCONET cohort study with paired inspiratory-expiratory CT were included. Fully automatic software, developed in-house, segmented arterial and venous pulmonary vessels and quantified volume and tortuosity on inspiratory and expiratory scans. The association between vessel volume normalised to lung volume and tortuosity versus lung function (forced expiratory volume in 1 sec [FEV1]), air trapping (residual volume to total lung capacity ratio [RV/TLC]), transfer factor for carbon monoxide (TLCO), disease severity in terms of Global Initiative for Chronic Obstructive Lung Disease (GOLD) group D, and mortality were analysed by linear, logistic or Cox proportional hazard regression. Results: Complete data were available from 138 patients (39% female, mean age 65 years). FEV1, RV/TLC and TLCO, all as % predicted, were significantly (p < 0.05 each) associated with expiratory vessel characteristics, predominantly venous volume and arterial tortuosity. Associations with inspiratory vessel characteristics were absent or negligible. The patterns were similar for relationships between GOLD D and mortality with vessel characteristics. Expiratory venous volume was an independent predictor of mortality, in addition to FEV1. Conclusion: By using automated software in patients with COPD, clinically relevant information on pulmonary vasculature can be extracted from expiratory CT scans (although not inspiratory scans); in particular, expiratory pulmonary venous volume predicted mortality. Trial Registration: NCT01245933.

Assessment of bronchodilator response in preschoolers: A systematic review.

BACKGROUND: Several techniques can be used to assess bronchodilator response (BDR) in preschool-aged children, including spirometry, respiratory oscillometry, the interrupter technique, and specific airway resistance. However, there has not been a systematic comparison of BDR thresholds across studies yet. METHODS: A systematic review was performed on all studies up to May 2023 measuring a bronchodilator effect in children 2-6 years old using one of these techniques (PROSPERO CRD42021264659). Studies were identified using MEDLINE, Cochrane, EMBASE, CINAHL via EBSCO, Web of Science databases, and reference lists of relevant manuscripts. RESULTS: Of 1224 screened studies, 43 were included. Over 85% were from predominantly European ancestry populations, and only 22 studies (51.2%) calculated a BDR cutoff based on a healthy control group. Five studies included triplicate testing with a placebo to account for the within-subject intrasession repeatability. A relative BDR was most consistently reported by the included studies (95%) but varied widely across all techniques. Various statistical methods were used to define a BDR, with six studies using receiver operating characteristic analyses to measure the discriminative power to distinguish healthy from wheezy and asthmatic children. CONCLUSION: A BDR in 2- to 6-year-olds cannot be universally defined based on the reviewed literature due to inconsistent methodology and cutoff calculations. Further studies incorporating robust methods using either distribution-based or clinical anchor-based approaches to define BDR are required.

Association Between Urinary Phthalate Metabolites and Chronic Obstructive Pulmonary Disease: A Cross-Sectional Study.

Objective: To determine the association of urinary phthalate metabolites with chronic obstructive pulmonary disease (COPD), airflow obstruction, lung function and respiratory symptoms. Methods: Our study included a total of 2023 individuals aged ≥ 40 years old in the National Health and Nutrition Examination Survey (NHANES). Multivariate logistic regression was conducted to explore the correlation of eleven urinary phthalate metabolites (MCNP, MCOP, MECPP, MnBP, MCPP, MEP, MEHHP, MEHP, MiBP, MEOHP, and MBzP) with COPD, airflow obstruction and respiratory symptoms. Linear regression analyses were used to evaluate the relationship between urinary phthalate metabolites and lung function. Results: When compared to the first tertile, the third tertile of MEHHP was associated with the risk of COPD [OR: 2.779; 95% confidence interval (CI): 1.129-6.840; P = 0.026]. Stratified analysis showed that MEHHP increased the risk of COPD by 7.080 times in male participants. Both MCPP and MBzP were positively correlated with the risk of airflow obstruction. The third tertile of MBzP increased the risk of cough by 1.545 (95% CI: 1.030-2.317; P = 0.035) times. Both FEV1 and FVC were negatively associated with MEHHP, MECPP, MnBP, MEP, MiBP and MEOHP. Conclusion: Higher levels of MEHHP are associated with increased risk of COPD, and lower measures of FEV1 and FVC. MBzP is positively related to airflow obstruction and cough.

Demographic factors associated with within-individual variability of lung function for adults with cystic fibrosis: A UK registry study.

BACKGROUND: Lung function is a key outcome used in the evaluation of disease progression in cystic fibrosis. The variability of individual lung function measurements over time (within-individual variability) has been shown to predict subsequent lung function changes. Nevertheless, the association between within-individual lung function variability and demographic and genetic covariates has not been quantified. METHODS: We performed a longitudinal analysis of data from a cohort of 7099 adults with cystic fibrosis (between 18 and 49 years old) from the UK cystic fibrosis registry, containing annual review data between 1996 and 2020. A mixed-effects location-scale model is used to quantify mean FEV1 (forced expiratory volume in 1 s) trajectories and FEV1 within-individual variability as a function of sex, age at annual review, diagnosis after first year of life, homozygous F508 genotype and birth cohort. RESULTS: Mean FEV1 decreased with age and lung function variability showed a near-quadratic trend by age. Males showed higher FEV1 mean and variability than females across the whole age range. Earlier diagnosis and homozygous F508 genotype were also associated with higher FEV1 mean and variability. Individuals who died during follow-up showed on average higher lung function variability than those who survived. CONCLUSIONS: Key variables known to be linked with mean lung function in cystic fibrosis are also associated with an individual's lung function variability. This work opens new avenues to understand the role played by lung function variability in disease progression and its utility in predicting key outcomes such as mortality.

Green spaces and respiratory, cardiometabolic, and neurodevelopmental outcomes: An individual-participant data meta-analysis of >35.000 European children.

Studies evaluating the benefits and risks of green spaces on children's health are scarce. The present study aimed to examine the associations between exposure to green spaces during pregnancy and early childhood with respiratory, cardiometabolic, and neurodevelopmental outcomes in school-age children. We performed an Individual-Participant Data (IPD) meta-analysis involving 35,000 children from ten European birth cohorts across eight countries. For each participant, we calculated residential Normalized Difference Vegetation Index (NDVI) within a 300 m buffer and the linear distance to green spaces (meters) during prenatal life and childhood. Multiple harmonized health outcomes were selected: asthma and wheezing, lung function, body mass index, diastolic and systolic blood pressure, non-verbal intelligence, internalizing and externalizing problems, and ADHD symptoms. We conducted a two-stage IPD meta-analysis and evaluated effect modification by socioeconomic status (SES) and sex. Between-study heterogeneity was assessed via random-effects meta-regression. Residential surrounding green spaces in childhood, not pregnancy, was associated with improved lung function, particularly higher FEV1 (ß = 0.06; 95 %CI: 0.03, 0.09 I2 = 4.03 %, p < 0.001) and FVC (ß = 0.07; 95 %CI: 0.04, 0.09 I2 = 0 %, p < 0.001) with a stronger association observed in females (p < 0.001). This association remained robust after multiple testing correction and did not change notably after adjusting for ambient air pollution. Increased distance to green spaces showed an association with lower FVC (ß = -0.04; 95 %CI: -0.07, -0.02, I2 = 4.8, p = 0.001), with a stronger effect in children from higher SES backgrounds (p < 0.001). No consistent associations were found between green spaces and asthma, wheezing, cardiometabolic, or neurodevelopmental outcomes, with direction of effect varying across cohorts. Wheezing and neurodevelopmental outcomes showed high between-study heterogeneity, and the age at outcome assessment was only associated with heterogeneity in internalizing problems.. This large European meta-analysis suggests that childhood exposure to green spaces may lead to better lung function. Associations with other respiratory outcomes and selected cardiometabolic and neurodevelopmental outcomes remain inconclusive.

Bioelectrical impedance and lung function-associations with gender and central obesity: results of the EpiHealth study.

BACKGROUND: Obesity is a major public health concern associated with various health problems, including respiratory impairment. Bioelectrical impedance (BIA) is used in health screening to assess body fat. However, there is no consensus in healthcare on how body fat should be assessed in relation to lung function. In this study, we aimed to investigate how BIA in relation to waist circumference contribute, using data from a large Swedish population study. METHODS: A total of 17,097 participants (aged 45-75 years) were included in the study. The relationships between fat mass, waist circumference, and lung function were analysed using weighted quantile sum regression. RESULTS: Increased fat mass was significantly associated with decreased lung function (FEV1, FVC) in both sexes. Also, the influence of trunk fat and waist circumference on FVC and FEV1 differed by sex: in males, waist circumference and trunk fat had nearly equal importance for FVC (variable weights of 0.42 and 0.41), whereas in females, trunk fat was significantly more important (variable weights 0.84 and 0.14). For FEV1, waist circumference was more important in males, while trunk fat was more significant in females (variable weights male 0.68 and 0.28 and 0.23 and 0.77 in female). CONCLUSIONS: Our results suggest that trunk fat should be considered when assessing the impact of adipose tissue on lung function and should potentially be included in the health controls.

Automatic planning for functional lung avoidance radiotherapy based on function-guided beam angle selection and plan optimization.

OBJECTIVE: This study aims to develop a fully Automatic Planning framework for Functional Lung Avoidance Radiotherapy (AP-FLART). Approach: The AP-FLART integrates a dosimetric score-based beam angle selection method and a meta-optimization-based plan optimization method, both of which incorporate lung function information to guide dose redirection from high-functional lung (HFL) to low-functional lung (LFL). It is applicable to both contour-based FLART (cFLART) and voxel-based FLART (vFLART) optimization options. A cohort of 18 lung cancer patient cases underwent planning-CT and SPECT perfusion scans were collected. AP-FLART was applied to generate conventional RT (ConvRT), cFLART, and vFLART plans for all cases. We compared automatic against manual ConvRT plans as well as automatic ConvRT against FLART plans, to evaluate the effectiveness of AP-FLART. Ablation studies were performed to evaluate the contribution of function-guided beam angle selection and plan optimization to dose redirection. Main results: Automatic ConvRT plans generated by AP-FALRT exhibited similar quality compared to manual counterparts. Furthermore, compared to automatic ConvRT plans, HFL mean dose, V20, and V5 were significantly reduced by 1.13 Gy (p<.001), 2.01% (p<.001), and 6.66% (p<.001) respectively for cFLART plans. Besides, vFLART plans showed a decrease in lung functionally weighted mean dose by 0.64 Gy (p<.01), fV20 by 0.90% (p=0.099), and fV5 by 5.07% (p<.01) respectively. Though inferior conformity was observed, all dose constraints were well satisfied. The ablation study results indicated that both function-guided beam angle selection and plan optimization significantly contributed to dose redirection. Significance: AP-FLART can effectively redirect doses from HFL to LFL without severely degrading conventional dose metrics, producing high-quality FLART plans. It has the potential to advance the research and clinical application of FLART by providing labor-free, consistent, and high-quality plans. Keywords: Functional lung avoidance radiotherapy; Automatic planning; Beam angle selection; Plan optimization.

Colchicine to reduce coronavirus disease-19-related inflammation and cardiovascular complications in high-risk patients post-acute infection with SARS-COV-2-a study protocol for a randomized controlled trial.

BACKGROUND: There is no known effective pharmacological therapy for long COVID, which is characterized by wide-ranging, multisystemic, fluctuating, or relapsing symptoms in a large proportion of survivors of acute COVID. This randomized controlled trial aims to assess the safety and efficacy of an anti-inflammatory agent colchicine, to reduce symptoms among those at high risk of developing long COVID. METHODS: This multi-centre, parallel arm, 1:1 individual randomized, placebo-controlled, double-blind superiority trial will enrol 350 individuals with persistent post-COVID symptoms. Participants will be randomized to either colchicine 0.5 mg once daily (< 70 kg) or twice daily (≥ 70 kg) or matched placebo for 26 weeks and will be followed up until 52 weeks after randomization. The primary trial objective is to demonstrate the superiority of colchicine over a placebo in improving distance walked in 6 min at 52 weeks from baseline. The secondary objectives are to assess the efficacy of colchicine compared to placebo with respect to lung function, inflammatory markers, constitutional symptoms, and mental health state. In a sub-sample of 100 participants, cardiac biomarkers of myocardial injury and myocardial oedema using MRI will be compared. DISCUSSION: Persistent inflammatory response following SARS-CoV-19 is one of the postulated pathophysiological mechanisms of long COVID. Colchicine, a low-cost anti-inflammatory agent, acts via multiple inflammatory pathways and has an established safety profile. This trial will generate evidence for an important health priority that can rapidly translate into practice. TRIAL REGISTRATION: This clinical trial has been registered prospectively on www. CLINICALTRIALS: gov with registration CTRI/2021/11/038234 dated November 24, 2021.

Long-Term Functional Limitations and Predictors of Recovery after COVID-19: A Multicenter Prospective Cohort Study.

BACKGROUND: Limited data exist on post-severe COVID-19 functional trajectory, particularly considering premorbid status. We characterized 1-year functional recovery post-hospitalization for COVID-19, highlighting predictors of long-term recovery. METHODS: We enrolled adult patients with lab-confirmed SARS-CoV-2 infection and hospitalized for COVID-19 sequelae, from five major Ontario, Canada hospitals in a prospective cohort study. Assessments included telephone interviews on admission followed by telephone and in-person assessments at 3-, 6-, 9-, and 12-months post-discharge. The Activity-Measure for Post-Acute Care (AM-PAC) Mobility and Cognition scales were administered at baseline and every 3 months for 1 year. Secondary outcomes included symptoms, spirometry, physical performance, dyspnea, fatigue, distress, anxiety and depression, and quality of life. RESULTS: 254 patients (57.1% male) with a mean age of 60.0 (±13.1) years and an average hospital stay of 14.3 (±19.7) days agreed to participate. At 12 months, 55.3% demonstrated clinically important deficits in mobility and 38.8% had cognitive deficits compared to premorbid levels. Fatigue was reported in 44.2%, followed by difficulty walking long distances in 35.8% and dyspnea in 33.0%. Almost 40% of patients had an FEV1(% Pred) < 80% at 12 months, 60.3% had impairments in physical performance, and 44.5% had problems with anxiety or depression. Predictors of better mobility at 12 months included higher premorbid mobility status, male sex, shorter hospital stay, fewer comorbidities, and higher FEV1 (% pred) at the 3-month follow-up. CONCLUSIONS: Our study provides compelling evidence of the long-term impact of COVID-19 on functional and cognitive status 1-year post-infection.

Effectiveness of manual therapy interventions in cystic fibrosis care: a pilot study.

BACKGROUND: Cystic fibrosis (CF) is a severe genetic condition that affects multiple organ systems and imposes a substantial treatment burden. Regarding the lungs and airways, the progressive pathophysiological changes place a significant strain on the musculoskeletal components of the respiratory system for people with CF. This pilot study investigated the effectiveness of manual therapy interventions (MTIs) on thoracic mobility, respiratory muscle strength, lung function, and musculoskeletal pain. METHOD: A study with a pretest-posttest design was conducted with 15 eligible people with CF at the Sahlgrenska University Hospital CF Centre. After an initial set of diagnostic tests at baseline, the participants underwent eight weekly 30-min MTIs. The MTIs included passive joint mobilisation and soft tissue manipulation of primary and secondary anatomical areas of the musculoskeletal respiratory system. On the day of the final intervention, the baseline measurements were repeated. RESULTS: Trends of increased thoracic mobility were observed following the intervention, with a statistically significant increase in respiratory muscle strength. No change in lung function was observed. Musculoskeletal pain before and after the intervention showed a significant decrease in tender points, and all participants reported positive experiences with MTIs. CONCLUSION: MTIs may improve thoracic mobility, alleviate pain, and enhance respiratory muscle strength in people with CF. Further research is needed to confirm their potential role as a CF physiotherapy supplement. CLINICAL TRIAL ID: NCT04696198.

Corrigendum: Effect of elexacaftor-tezacaftor-ivacaftor on nasal potential difference and lung function in Phe508del rats.

[This corrects the article DOI: 10.3389/fphar.2024.1362325.].

Characteristics of adults with severe asthma in childhood - A 60-year Follow-up Study.

BACKGROUND: Childhood asthma is a prevalent condition with potential impact on adult life. RESEARCH QUESTION: In 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 METHODS: Danish 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. RESULTS: Among 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. INTERPRETATION: Our 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.

Personal exposure to airborne organic pollutants and lung function changes among healthy older adults.

Epidemiological evidence on the impact of airborne organic pollutants on lung function among the elderly is limited, and their underlying biological mechanisms remain largely unexplored. Herein, a longitudinal panel study was conducted in Jinan, Shandong Province, China, involving 76 healthy older adults monitored over a span of five months repetitively. We systematically evaluated personal exposure to a diverse range of airborne organic pollutants using a wearable passive sampler and their effects on lung function. Participants' pulmonary function indicators were assessed, complemented by comprehensive multi-omics analyses of blood and urine samples. Leveraging the power of interaction analysis, causal inference test (CIT), and integrative pathway analysis (IPA), we explored intricate relationships between specific organic pollutants, biomolecules, and lung function deterioration, elucidating the biological mechanisms underpinning the adverse impacts of these pollutants. We observed that bis (2-chloro-1-methylethyl) ether (BCIE) was significantly associated with negative changes in the forced vital capacity (FVC), with glycerolipids mitigating this adverse effect. Additionally, 31 canonical pathways [e.g., high mobility group box 1 (HMGB1) signaling, phosphatidylinositol 3-kinase (PI3K)/AKT pathway, epithelial mesenchymal transition, and heme and nicotinamide adenine dinucleotide (NAD) biosynthesis] were identified as potential mechanisms. These findings may hold significant implications for developing effective strategies to prevent and mitigate respiratory health risks arising from exposure to such airborne pollutants. However, due to certain limitations of the study, our results should be interpreted with caution.

The respiratory health effects of acute in vivo diesel and biodiesel exhaust in a mouse model.

BACKGROUND: Biodiesel, a renewable diesel fuel that can be created from almost any natural fat or oil, is promoted as a greener and healthier alternative to commercial mineral diesel without the supporting experimental data to back these claims. The aim of this research was to assess the health effects of acute exposure to two types of biodiesel exhaust, or mineral diesel exhaust or air as a control in mice. Male BALB/c mice were exposed for 2-hrs to diluted exhaust obtained from a diesel engine running on mineral diesel, Tallow biodiesel or Canola biodiesel. A room air exposure group was used as a control. Twenty-four hours after exposure, a variety of respiratory related end point measurements were assessed, including lung function, responsiveness to methacholine and airway and systemic immune responses. RESULTS: Tallow biodiesel exhaust exposure resulted in the greatest number of significant effects compared to Air controls, including increased airway hyperresponsiveness (178.1 ± 31.3% increase from saline for Tallow biodiesel exhaust exposed mice compared to 155.8 ± 19.1 for Air control), increased airway inflammation (63463 ± 13497 cells/mL in the bronchoalveolar lavage of Tallow biodiesel exhaust exposed mice compared to 40561 ± 11800 for Air exposed controls) and indications of immune dysregulation. In contrast, exposure to Canola biodiesel exhaust resulted in fewer significant effects compared to Air controls with a slight increase in airway resistance at functional residual capacity and indications of immune dysregulation. Exposure to mineral diesel exhaust resulted in significant effects between that of the two biodiesels with increased airway hyperresponsiveness and indications of immune dysregulation. CONCLUSION: These data show that a single, brief exposure to biodiesel exhaust can result in negative health impacts in a mouse model, and that the biological effects of exposure change depending on the feedstock used to make the biodiesel.

Spirometric Transition of at Risk Individuals and Risks for Progression to Chronic Obstructive Pulmonary Disease in General Population.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is a dynamic disease with a high socioeconomic burden. Using data collected prospectively from the general population, we examined factors related to the transition of at-risk individuals to COPD. METHODS: We used the Korean Genome Epidemiology Study (KoGES) database, defining pre-COPD based on respiratory symptoms and radiological abnormalities suggestive of COPD; the preserved ratio impaired spirometry (PRISm) was defined as a forced expiratory volume in 1s (FEV1)/forced vital capacity ratio≥70% and FEV1<80%, as predicted by spirometry. We determined group differences in the rate of lung function decline, risk of future airflow obstruction (AFO). RESULTS: The study included 4762 individuals, and longitudinal analysis revealed distinct trends in pulmonary function indicators. Compared to the normal group, the pre-COPD group showed a more rapid decline in lung function, while the PRISm group showed a slower decline. In the pre-COPD and PRISm groups, 4.4% and 3.5%, and 13.6% and 10.8%, respectively, of patients had progressed to COPD at the first and second visits. Pre-COPD and PRISm contributed to an earlier time to first AFO, but consideration of comorbid cardiovascular disease weakened this relationship in the PRISm group. Multivariate logistic regression showed that pre-COPD and PRISm are significant risk factors for future development of COPD (OR 1.80, p<0.001; OR 4.26, p<0.001, respectively). CONCLUSION: Pre-COPD and PRISm patients showed different trends in lung function changes over time and both were significant risk factors for future development of COPD.