Early life insults as determinants of chronic obstructive pulmonary disease in adult life

Mediating Effect of Tobacco Dependence on the Association Between Maternal Smoking During Pregnancy and Chronic Obstructive Pulmonary Disease: Case-Control Study

BACKGROUND

Maternal smoking during pregnancy (MSDP) is a known risk factor for offspring developing chronic obstructive pulmonary disease (COPD), but the underlying mechanism remains unclear.

OBJECTIVE

This study aimed to explore whether the increased COPD risk associated with MSDP could be attributed to tobacco dependence (TD).

METHODS

This case-control study used data from the nationwide cross-sectional China Pulmonary Health study, with controls matched for age, sex, and smoking status. TD was defined as smoking within 30 minutes of waking, and the severity of TD was assessed using the Fagerstrom Test for Nicotine Dependence. COPD was diagnosed when the ratio of forced expiratory volume in 1 second to forced vital capacity was <0.7 in a postbronchodilator pulmonary function test according to the 2017 Global Initiative for Chronic Obstructive Lung Disease criteria. Logistic regression was used to examine the correlation between MSDP and COPD, adjusting for age, sex, BMI, educational attainment, place of residence, ethnic background, occupation, childhood passive smoking, residential fine particulate matter, history of childhood pneumonia or bronchitis, average annual household income, and medical history (coronary heart disease, hypertension, and diabetes). Mediation analysis examined TD as a potential mediator in the link between MSDP and COPD risk. The significance of the indirect effect was assessed through 1000 iterations of the "bootstrap" method.

RESULTS

The study included 5943 participants (2991 with COPD and 2952 controls). Mothers of the COPD group had higher pregnancy smoking rates (COPD: n=305, 10.20%; controls: n=211, 7.10%; P<.001). TD was more prevalent in the COPD group (COPD: n=582, 40.40%; controls: n=478, 33.90%; P<.001). After adjusting for covariates, MSDP had a significant effect on COPD (β=.097; P<.001). There was an association between MSDP and TD (β=.074; P<.001) as well as between TD and COPD (β=.048; P=.007). Mediation analysis of TD in the MSDP-COPD association showed significant direct and indirect effects (direct: β=.094; P<.001 and indirect: β=.004; P=.03). The indirect effect remains present in the smoking population (direct: β=.120; P<.001 and indirect: β=.002; P=.03).

CONCLUSIONS

This study highlighted the potential association between MSDP and the risk of COPD in offspring, revealing the mediating role of TD in this association. These findings contribute to a deeper understanding of the impact of prenatal tobacco exposure on lung health, laying the groundwork for the development of relevant prevention and treatment strategies.

Large airway T cells in adults with former bronchopulmonary dysplasia

BACKGROUND

Bronchopulmonary Dysplasia (BPD) in infants born prematurely is a risk factor for chronic airway obstruction later in life. The distribution of T cell subtypes in the large airways is largely unknown.

OBJECTIVE

To characterize cellular and T cell profiles in the large airways of young adults with a history of BPD.

METHODS

Forty-three young adults born prematurely (preterm (n = 20), BPD (n = 23)) and 45 full-term-born (asthma (n = 23), healthy (n = 22)) underwent lung function measurements, and bronchoscopy with large airway bronchial wash (BW). T-cells subsets in BW were analyzed by immunocytochemistry.

RESULTS

The proportions of both lymphocytes and CD8 + T cells in BW were significantly higher in BPD (median, 6.6%, and 78.0%) when compared with asthma (3.4% and 67.8%, p = 0.002 and p = 0.040) and healthy (3.8% and 40%, p < 0.001 and p < 0.001). In all adults born prematurely (preterm and BPD), lymphocyte proportion correlated negatively with forced vital capacity (r= -0.324, p = 0.036) and CD8 + T cells correlated with forced expiratory volume in one second, FEV1 (r=-0.448, p = 0.048). Correlation-based network analysis revealed that lung function cluster and BPD-birth cluster were associated with lymphocytes and/or CD4 + and CD8 + T cells. Multivariate regression analysis showed that lymphocyte proportions and BPD severity qualified as independent factors associated with FEV1.

CONCLUSIONS

The increased cytotoxic T cells in the large airways in young adults with former BPD, suggest a similar T-cell subset pattern as in the small airways, resembling features of COPD. Our findings strengthen the hypothesis that mechanisms involving adaptive and innate immune responses are involved in the development of airway disease due to preterm birth.

Effect of In utero Exposure to Air Pollution on Adulthood Hospitalizations

Empirical analyses have demonstrated that individuals exposed to severe air pollution in utero have worse health outcomes during childhood. However, there is little evidence on the long-term health impacts of air pollution exposure. The objective of this paper is to estimate the effect of in utero exposure to the Great London Smog of 1952 (GLS) on five health outcomes identified through a scoping review to be those most likely affected: respiratory, circulatory, neoplasms, mental health, and nervous system conditions. We use the GLS, an extreme air pollution event in December 1952, as a quasi-natural experiment to estimate the effect of exposure to air pollution in utero on adulthood health. Data from the UK Biobank is analysed for a cohort of participants born from December 1952 to July 1956. Differences in health outcomes between adults exposed and not exposed to the GLS due to their birth dates, born inside and outside London, were explored. Our primary focus is hospitalization events between 1997 and 2020 (corresponding to ages 40 to 69), as recorded in linked administrative data from the National Health Service (NHS). Specifically, the five primary outcomes are binary variables indicating that the individual had at least one hospitalization where the main cause of hospitalization is related to respiratory, circulatory, neoplasms, mental health, or nervous system conditions. The analytical sample comprised 36,281 individuals. A positive effect on adulthood hospitalizations due to respiratory conditions was observed. If exposed to the GLS in utero, the probability of at least one respiratory health-related hospitalization between 1997 and 2020 increased by 2.58 percentage points (95% CI 0.08, 4.30, p = 0.03), a 23% increase relative to the sample mean. Small effects were found for all other outcomes, suggesting that these conditions were not affected by the GLS. We do not find heterogeneous effects by sex or childhood socioeconomic status. This study found that a 5-day pollution exposure event while in utero significantly increased respiratory-related hospitalizations at ages 40 to 69 but had no impact on hospitalizations due to circulatory, neoplasms, mental health, and nervous system conditions.

A Longitudinal Study of a Selected Pediatric Asthmatic Population with Normal and Abnormal Spirometry at Baseline: An Emphasis on Treatment Outcomes

Purpose

It is still unclear whether considering abnormal spirometry as a marker for disease control can help physicians adjust asthma controllers in children because of the scarcity of pediatric studies. We aimed to investigate the prevalence of abnormal spirometry in a selected pediatric asthmatic population and its effect on longitudinal outcomes.

Patients and Methods

This retrospective cohort study was conducted at the Songklanagarind Hospital, Thailand. Children with asthma aged <18 years were recruited for review if they attended the clinic and underwent acceptable spirometry with bronchodilator responsiveness (BDR) tests after receiving asthma treatment for at least 3 months between January 2011 and June 2022. Differences in baseline characteristics, atopic factors, asthma treatment, and outcomes were analyzed between the normal and abnormal spirometry groups over a 12-month post-spirometry period.

Results

The mean age of the 203 enrolled patients was 10.9 ± 2.6 years. Abnormal spirometry, defined as airflow limitation or the presence of BDR, was observed in 58.1% of patients. No significant differences were observed in baseline characteristics, atopic factors, asthma treatment, or outcomes between the normal and abnormal spirometry groups. Further analysis of 107 patients with abnormal spirometry with symptom control revealed that physicians adjusted the asthma controller based on spirometry and symptoms in 84 and 23 patients, respectively. There was no significant difference in the loss of disease control over the 12-month post-spirometry period between the two groups.

Conclusion

Abnormal spirometry was found in 58.1% of treated school-aged patients with asthma. Abnormal spirometry results were not associated with poor asthma outcomes during the 12-month follow-up. Both symptom-based and spirometry-based adjustments of asthma controllers resulted in comparable symptom control over a 12-month follow-up period in the selected population.

An investigation of the risk factors of chronic obstructive pulmonary disease in natural population-based cohorts in China - a nested case-control study

Background

Chronic obstructive pulmonary disease (COPD) has become one of the most significant chronic diseases in China. According to conventional wisdom, smoking is the pathogenic factor. However, current research indicates that the pathophysiology of COPD may be associated with prior respiratory system events (e.g., childhood hospitalization for pneumonia, chronic bronchitis) and environmental exposure (e.g., dust from workplace, indoor combustion particles). Dyspnea, persistent wheezing, and other respiratory symptoms further point to the need for pulmonary function tests in this population. Reducing the burden of chronic diseases in China requires a thorough understanding of the various factors that influence the occurrence of COPD.

Methods

Using a cohort from the natural population, this study used nested case-control analysis. We carried out a number of researches, including questionnaire surveys and pulmonary function testing, in the Northwest and Southeast cohorts of China between 2014 and 2021. After removing any variations in the baseline data between patients and control subjects using propensity score matching analysis, the risk factors were examined using univariate or multivariate regression.

Result

It was discovered that prior history of chronic bronchitis, long-term wheezing symptoms, and environmental exposure-including smoking and biofuel combustion-were risk factors for COPD. Dyspnea, symptoms of mobility limitation, organic matter, and a history of hospitalization for pneumonia at an early age were not significant in the clinical model but their incidence in COPD group is higher than that in healthy population.

Discussion

COPD screening effectiveness can be increased by looking for individuals with chronic respiratory symptoms. Smokers should give up as soon as they can, and families that have been exposed to biofuels for a long time should convert to clean energy or upgrade their ventilation. Individuals who have previously been diagnosed with emphysema and chronic bronchitis ought to be extra mindful of the prevention or advancement of COPD.

Childhood secondhand smoke exposure and respiratory disease mortality among never-smokers: the Japan collaborative cohort study for evaluation of cancer risk

BACKGROUND

The main source of secondhand smoke (SHS) exposure during childhood occurs at home due to close family members who smoke. This study examined the association between childhood SHS exposure and the risk of respiratory disease mortality among non-smoking adults.

METHODS

Data from 44 233 never-smoking Japanese men and women aged 40-79 years who participated in the JACC study between 1988 and 1990 were analyzed. The Cox proportional hazards model was used to calculate hazard ratios and 95% confidence intervals of respiratory disease mortality according to the number of smoking family members during childhood. Subdistribution HRs (SHRs) were calculated as a competing risk analysis.

RESULTS

A total of 735 deaths from respiratory diseases were documented in a median follow-up of 19.2 years. Living with three or more smoking family members during childhood was associated with a higher risk of respiratory disease mortality in adulthood among women; multivariable SHR compared with participants with no family member smokers during childhood was 1.60 (1.01-2.54) for participants with three or more family members who smoked during their childhood.

CONCLUSIONS

SHS exposure from three or more family members during childhood was associated with an increased risk of respiratory disease-related mortality in adulthood.

Management of Chronic Obstructive Pulmonary Disease (COPD) Exacerbations in Hospitalized Patients From Admission to Discharge: A Comprehensive Review of Therapeutic Interventions

Chronic obstructive pulmonary disease (COPD) is a common and debilitating condition that often necessitates hospitalization for exacerbations. Since COPD exacerbations can cause significant morbidity and mortality, managing them is crucial for patient care. Effective management of COPD exacerbations is essential to prevent complications, as COPD exacerbations are associated with increased healthcare costs and decreased quality of life. This review aims to comprehensively discuss the management of COPD exacerbations, covering various pharmacologic and non-pharmacologic strategies. These include inhaled bronchodilators, systemic steroids, antibiotics, invasive and non-invasive ventilation, oxygen therapy, smoking cessation, immunization with pneumococcal vaccine, inhalers at discharge, pulmonary rehabilitation, long-term oxygen therapy (LTOT), ambulatory oxygen therapy, short-burst oxygen therapy, extracorporeal membrane oxygenation (ECMO), lung volume reduction surgery (LVRS), endobronchial procedures, and lung transplant. It is drawn upon various sources, including clinical studies, systemic reviews, and observational studies, to provide a comprehensive overview of current practices and identify areas for future research and innovation in managing COPD exacerbations. Addressing these areas of interest can improve patient outcomes and quality of life.

Oxygen and mechanical stretch in the developing lung: risk factors for neonatal and pediatric lung disease

Chronic airway diseases, such as wheezing and asthma, remain significant sources of morbidity and mortality in the pediatric population. This is especially true for preterm infants who are impacted both by immature pulmonary development as well as disproportionate exposure to perinatal insults that may increase the risk of developing airway disease. Chronic pediatric airway disease is characterized by alterations in airway structure (remodeling) and function (increased airway hyperresponsiveness), similar to adult asthma. One of the most common perinatal risk factors for development of airway disease is respiratory support in the form of supplemental oxygen, mechanical ventilation, and/or CPAP. While clinical practice currently seeks to minimize oxygen exposure to decrease the risk of bronchopulmonary dysplasia (BPD), there is mounting evidence that lower levels of oxygen may carry risk for development of chronic airway, rather than alveolar disease. In addition, stretch exposure due to mechanical ventilation or CPAP may also play a role in development of chronic airway disease. Here, we summarize the current knowledge of the impact of perinatal oxygen and mechanical respiratory support on the development of chronic pediatric lung disease, with particular focus on pediatric airway disease. We further highlight mechanisms that could be explored as potential targets for novel therapies in the pediatric population.

Long-term implications of fetal growth restriction

Fetal growth restriction (FGR), or intrauterine growth restriction (IUGR), is a complication of pregnancy where the fetus does not achieve its genetic growth potential. FGR is characterized by a pathological retardation of intrauterine growth velocity in the curve of intrauterine growth. However, the FGR definition is still debated, and there is a lack of a uniform definition in the literature. True IUGR, compared to constitutional smallness, is a pathological condition in which the placenta fails to deliver an adequate supply of oxygen and nutrients to the developing fetus. Infants with IUGR, compared to appropriately grown gestational age infants, have a significantly higher risk of mortality and neonatal complications with long-term consequences. Several studies have demonstrated how suboptimal fetal growth leads to long-lasting physiological alterations for the developing fetus as well as for the newborn and adult in the future. The long-term effects of fetal growth retardation may be adaptations to poor oxygen and nutrient supply that are effective in the fetal period but deleterious in the long term through structural or functional alterations. Epidemiologic studies showed that FGR could be a contributing factor for adult chronic diseases including cardiovascular disease, metabolic syndrome, diabetes, respiratory diseases and impaired lung function, and chronic kidney disease. In this review we discussed pathophysiologic mechanisms of FGR-related complications and potential preventive measures for FGR.

Comparative analysis of pulmonary function in children born preterm and full-term at 6–9 years of age

Abstract Objective: To compare pulmonary function parameters and the prevalence of altered pulmonary function in children born preterm and full-term, using the Global Lung Initiative reference values. Methods: This is a cross-sectional study with 6–9-year-old children submitted to measurement of airway resistance (Rint) and spirometry according to the American Thoracic Society and European Respiratory Society Technical Statement. The inclusion criteria were, among the preterm group: gestational age <37 weeks and birth weight <2000g; among the full-term group: schoolchildren born full-term with birth weight >2500g, recruited at two public schools in São Paulo, Brazil, matched by sex and age with the preterm group. As exclusion criteria, congenital malformations, cognitive deficit, and respiratory problems in the past 15 days were considered. Results: A total of 112 children were included in each group. Preterm children had gestational age of 30.8±2.8 weeks and birth weight of 1349±334g. Among them, 46.6% were boys, 46.4% presented respiratory distress syndrome, 19.6% bronchopulmonary dysplasia, and 65.2% were submitted to mechanical ventilation in the neonatal unit. At study entry, both groups were similar in age and anthropometric parameters. Parameters of pulmonary function (Z scores) in preterm and full-term groups were: Rint (0.13±2.24 vs. -1.02±1.29; p<0.001); forced vital capacity (FVC) (-0.39±1.27 vs. -0.15±1.03; p=0.106), forced expiratory volume in one second (FEV1)/FVC (-0.23±1.22 vs. 0.14±1.11; p=0.003), FEV1 (-0.48±1.29 vs. -0.04±1.08; p=0.071), and forced expiratory flow between 25% and 75% of vital capacity (FEF25-75) (1.16±1.37 vs. 2.08±1.26; p=0.005), respectively. The prevalence values of altered airway resistance (16.1 vs. 1.8%; p<0.001) and spirometry (26.8 vs. 13.4%, p=0.012) were higher in preterm infants than in full-term ones. Conclusions: Preterm children had higher prevalence of altered pulmonary function, higher Z scores of airway resistance, and lower Z scores of FEV1/FVC and FEF25-75 compared with those born full-term.

Multi-omic association study identifies DNA methylation-mediated genotype and smoking exposure effects on lung function in children living in urban settings

Impaired lung function in early life is associated with the subsequent development of chronic respiratory disease. Most genetic associations with lung function have been identified in adults of European descent and therefore may not represent those most relevant to pediatric populations and populations of different ancestries. In this study, we performed genome-wide association analyses of lung function in a multiethnic cohort of children (n = 1,035) living in low-income urban neighborhoods. We identified one novel locus at the TDRD9 gene in chromosome 14q32.33 associated with percent predicted forced expiratory volume in one second (FEV1) (p = 2.4x10-9; βz = -0.31, 95% CI = -0.41- -0.21). Mendelian randomization and mediation analyses revealed that this genetic effect on FEV1 was partially mediated by DNA methylation levels at this locus in airway epithelial cells, which were also associated with environmental tobacco smoke exposure (p = 0.015). Promoter-enhancer interactions in airway epithelial cells revealed chromatin interaction loops between FEV1-associated variants in TDRD9 and the promoter region of the PPP1R13B gene, a stimulator of p53-mediated apoptosis. Expression of PPP1R13B in airway epithelial cells was significantly associated the FEV1 risk alleles (p = 1.3x10-5; β = 0.12, 95% CI = 0.06-0.17). These combined results highlight a potential novel mechanism for reduced lung function in urban youth resulting from both genetics and smoking exposure.

The Association of Self-Reported Birthweight with Lung Function and Respiratory Diseases: Results from a Multi-Centre, Multi-Case Control Study in Italy

Early life conditions are associated with lung function and the development of respiratory and non-respiratory illnesses. The relationship with birthweight (BW), however, is conflicting. We examined associations of self-reported BW with lung function and the development of respiratory and also non-respiratory diseases within the GEIRD (Gene-Environment Interaction in Respiratory Diseases) project, an Italian multi-centre, multi-case control study involving cases of COPD, asthma, allergic rhinitis and controls. Multinomial logistic regression was performed with case/control status as response variable; BW as main determinant; and adjusting for sex, age and smoking status. Of the 2287 participants reporting BW, 6.4% (n = 147) had low BW (<2500 g), and this proportion was greater in women than men (7.8% vs. 5.1%; p = 0.006). Both men and women with low BW were shorter than those with normal BW (mean ± SD: 160.2 ± 5.5 vs. 162.6 ± 6.5 cm in women, p = 0.009; 172.4 ± 6.1 vs. 174.8 ± 7.2 cm in men, p < 0.001). Although FEV1 and FVC were reduced in individuals with low BW, this was explained by associations with sex and height. In multivariable analysis, BW was not associated with respiratory diseases in adulthood. However, those with low BW had a higher risk of self-reported hospitalisation for lung disease before the age of two (10.3% vs. 4.1%; p < 0.001), severe respiratory infection before the age of five (16.9% vs. 8.8%; p = 0.001) and hypertension in adulthood (29.9% vs. 23.7%; p = 0.001); however, they had a lower risk of arrhythmia (2.7% vs. 5.8%; p = 0.027).

Identification of biomarkers for disease severity in nasopharyngeal secretions of infants with upper or lower respiratory tract viral infections

Lower respiratory tract infections (LRTIs) produced by viruses are the most frequent cause of morbidity and mortality in children younger than 5 years of age. The immune response triggered by viral infection can induce a strong inflammation in the airways and cytokines could be considered as biomarkers for disease severity as these molecules modulate the inflammatory response that defines the outcome of patients. Aiming to predict the severity of disease during respiratory tract infections, we conducted a 1-year follow-up observational study in infants who presented upper or lower respiratory tract infections caused by seasonal respiratory viruses. At the time of enrollment, nasopharyngeal swabs (NPS) were obtained from infants to measure mRNA expression and protein levels of IL-3, IL-8, IL-33, and thymic stromal lymphopoietin. While all cytokines significantly increased their protein levels in infants with upper and lower respiratory tract infections as compared to control infants, IL-33 and IL-8 showed a significant increase in respiratory syncytial virus (RSV)-infected patients with LRTI as compared to patients with upper respiratory tract infection. We also found higher viral loads of RSV-positive samples with a greater IL-8 response at the beginning of the symptoms. Data obtained in this study suggest that both IL-8 and IL-33 could be used as biomarkers for clinical severity for infants suffering from LRTIs caused by the RSV.

Therapeutic Potential of Small Molecules Targeting Oxidative Stress in the Treatment of Chronic Obstructive Pulmonary Disease (COPD): A Comprehensive Review

Chronic obstructive pulmonary disease (COPD) is an increasing and major global health problem. COPD is also the third leading cause of death worldwide. Oxidative stress (OS) takes place when various reactive species and free radicals swamp the availability of antioxidants. Reactive nitrogen species, reactive oxygen species (ROS), and their counterpart antioxidants are important for host defense and physiological signaling pathways, and the development and progression of inflammation. During the disturbance of their normal steady states, imbalances between antioxidants and oxidants might induce pathological mechanisms that can further result in many non-respiratory and respiratory diseases including COPD. ROS might be either endogenously produced in response to various infectious pathogens including fungi, viruses, or bacteria, or exogenously generated from several inhaled particulate or gaseous agents including some occupational dust, cigarette smoke (CS), and air pollutants. Therefore, targeting systemic and local OS with therapeutic agents such as small molecules that can increase endogenous antioxidants or regulate the redox/antioxidants system can be an effective approach in treating COPD. Various thiol-based antioxidants including fudosteine, erdosteine, carbocysteine, and N-acetyl-L-cysteine have the capacity to increase thiol content in the lungs. Many synthetic molecules including inhibitors/blockers of protein carbonylation and lipid peroxidation, catalytic antioxidants including superoxide dismutase mimetics, and spin trapping agents can effectively modulate CS-induced OS and its resulting cellular alterations. Several clinical and pre-clinical studies have demonstrated that these antioxidants have the capacity to decrease OS and affect the expressions of several pro-inflammatory genes and genes that are involved with redox and glutathione biosynthesis. In this article, we have summarized the role of OS in COPD pathogenesis. Furthermore, we have particularly focused on the therapeutic potential of numerous chemicals, particularly antioxidants in the treatment of COPD.

Novel Lung Growth Strategy with Biological Therapy Targeting Airway Remodeling in Childhood Bronchial Asthma

Anti-inflammatory therapy, centered on inhaled steroids, suppresses airway inflammation in asthma, reduces asthma mortality and hospitalization rates, and achieves clinical remission in many pediatric patients. However, the spontaneous remission rate of childhood asthma in adulthood is not high, and airway inflammation and airway remodeling persist after remission of asthma symptoms. Childhood asthma impairs normal lung maturation, interferes with peak lung function in adolescence, reduces lung function in adulthood, and increases the risk of developing chronic obstructive pulmonary disease (COPD). Early suppression of airway inflammation in childhood and prevention of asthma exacerbations may improve lung maturation, leading to good lung function and prevention of adult COPD. Biological drugs that target T-helper 2 (Th2) cytokines are used in patients with severe pediatric asthma to reduce exacerbations and airway inflammation and improve respiratory function. They may also suppress airway remodeling in childhood and prevent respiratory deterioration in adulthood, reducing the risk of COPD and improving long-term prognosis. No studies have demonstrated a suppressive effect on airway remodeling in childhood severe asthma, and further clinical trials using airway imaging analysis are needed to ascertain the inhibitory effect of biological drugs on airway remodeling in severe childhood asthma. In this review, we describe the natural prognosis of lung function in childhood asthma and the risk of developing adult COPD, the pathophysiology of allergic airway inflammation and airway remodeling via Th2 cytokines, and the inhibitory effect of biological drugs on airway remodeling in childhood asthma.

Health Outcomes in Children Associated with Prenatal and Early-Life Exposures to Air Pollution: A Narrative Review

(1) Background: The developmental origins of health and disease (DOHaD) hypothesis links adverse fetal exposures with developmental mal-adaptations and morbidity later in life. Short- and long-term exposures to air pollutants are known contributors to health outcomes; however, the potential for developmental health effects of air pollution exposures during gestation or early-childhood have yet to be reviewed and synthesized from a DOHaD lens. The objective of this study is to summarize the literature on cardiovascular and metabolic, respiratory, allergic, and neuropsychological health outcomes, from prenatal development through early childhood, associated with early-life exposures to outdoor air pollutants, including traffic-related and wildfire-generated air pollutants. (2) Methods: We conducted a search using PubMed and the references of articles previously known to the authors. We selected papers that investigated health outcomes during fetal or childhood development in association with early-life ambient or source-specific air pollution exposure. (3) Results: The current literature reports that prenatal and early-childhood exposures to ambient and traffic-related air pollutants are associated with a range of adverse outcomes in early life, including cardiovascular and metabolic, respiratory and allergic, and neurodevelopmental outcomes. Very few studies have investigated associations between wildfire-related air pollution exposure and health outcomes during prenatal, postnatal, or childhood development. (4) Conclusion: Evidence from January 2000 to January 2022 supports a role for prenatal and early-childhood air pollution exposures adversely affecting health outcomes during development. Future studies are needed to identify both detrimental air pollutants from the exposure mixture and critical exposure time periods, investigate emerging exposure sources such as wildfire, and develop feasible interventional tools.

Beyond the COPD-tobacco binomium: New opportunities for the prevention and early treatment of the disease

Chronic obstructive pulmonary disease (COPD) has been traditionally understood as a self-inflicted disease cause by tobacco smoking occurring in individuals older than 50-60 years. This traditional paradigm has changed over the last decade because new scientific evidence showed that there are many genetic (G) and environmental (E) factors associated with reduced lung function, that vary, accumulate, and interact over time (T), even before birth (G×E×T). This new perspective opens novel windows of opportunity for the prevention, early diagnosis, and personalized treatment of COPD. This review presents the evidence that supports this proposal, as well as its practical implications, with particular emphasis on the need that clinical histories in patients with suspected COPD should investigate early life events and that spirometry should be used much more widely as a global health marker.

Quality Standard Position Statements for Health System Policy Changes in Diagnosis and Management of COPD: A Global Perspective

Introduction

Despite being a leading cause of death worldwide, chronic obstructive pulmonary disease (COPD) is underdiagnosed and underprioritized within healthcare systems. Existing healthcare policies should be revisited to include COPD prevention and management as a global priority. Here, we propose and describe health system quality standard position statements that should be implemented as a consistent standard of care for patients with COPD.

Methods

A multidisciplinary group of clinicians with expertise in COPD management together with patient advocates from eight countries participated in a quality standards review meeting convened in April 2021. The principal objective was to achieve consensus on global health system priorities to ensure consistent standards of care for COPD. These quality standard position statements were either evidence-based or reflected the combined views of the panel.

Results

On the basis of discussions, the experts adopted five quality standard position statements, including the rationale for their inclusion, supporting clinical evidence, and essential criteria for quality metrics. These quality standard position statements emphasize the core elements of COPD care, including (1) diagnosis, (2) adequate patient and caregiver education, (3) access to medical and nonmedical treatments aligned with the latest evidence-based recommendations and appropriate management by a respiratory specialist when required, (4) appropriate management of acute COPD exacerbations, and (5) regular patient and caregiver follow-up for care plan reviews.

Conclusions

These practical quality standards may be applicable to and implemented at both local and national levels. While universally applicable to the core elements of appropriate COPD care, they can be adapted to consider differences in healthcare resources and priorities, organizational structure, and care delivery capabilities of individual healthcare systems. We encourage the adoption of these global quality standards by policymakers and healthcare practitioners alike to inform national and regional health system policy revisions to improve the quality and consistency of COPD care worldwide.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02137-x.

Lifetime exposure to smoking, epigenetic aging, and morbidity and mortality in older adults

BACKGROUND

Cigarette smoke is a major public health concern. Epigenetic aging may be an important pathway by which exposure to cigarette smoke affects health. However, little is known about how exposure to smoke at different life stages affects epigenetic aging, especially in older adults. This study examines how three epigenetic aging measures (GrimAge, PhenoAge, and DunedinPoAm38) are associated with parental smoking, smoking in youth, and smoking in adulthood, and whether these epigenetic aging measures mediate the link between smoke exposure and morbidity and mortality. This study utilizes data from the Health and Retirement Study (HRS) Venous Blood Study (VBS), a nationally representative sample of US adults over 50 years old collected in 2016. 2978 participants with data on exposure to smoking, morbidity, and mortality were included.

RESULTS

GrimAge is significantly increased by having two smoking parents, smoking in youth, and cigarette pack years in adulthood. PhenoAge and DunedinPoAm38 are associated with pack years. All three mediate some of the effect of pack years on cancer, high blood pressure, heart disease, and mortality and GrimAge and DunedinPoAm38 mediate this association on lung disease.

CONCLUSIONS

Results suggest epigenetic aging is one biological mechanism linking lifetime exposure to smoking with development of disease and earlier death in later life. Interventions aimed at reducing smoking in adulthood may be effective at weakening this association.

Lifelong Lung Sequelae of Prematurity

The clinical, functional, and structural pattern of chronic lung disease of prematurity has changed enormously in last years, mirroring a better perinatal management and an increasing lung immaturity with the survival of increasingly premature infants. Respiratory symptoms and lung function impairment related to prematurity seem to improve over time, but premature birth increases the likelihood of lung function impairment in late childhood, predisposing to chronic obstructive pulmonary disease (COPD). It is mandatory to identify those individuals born premature who are at risk for developing long-term lung disease through a better awareness of physicians, the use of standardized CT imaging scores, and a more comprehensive periodic lung function evaluation. The aim of this narrative review was to provide a systematic approach to lifelong respiratory symptoms, lung function impairment, and lung structural anomalies in order to better understand the specific role of prematurity on lung health.

Protein interaction networks provide insight into fetal origins of chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a leading cause of death in adults that may have origins in early lung development. It is a complex disease, influenced by multiple factors including genetic variants and environmental factors. Maternal smoking during pregnancy may influence the risk for diseases during adulthood, potentially through epigenetic modifications including methylation.

METHODS

In this work, we explore the fetal origins of COPD by utilizing lung DNA methylation marks associated with in utero smoke (IUS) exposure, and evaluate the network relationships between methylomic and transcriptomic signatures associated with adult lung tissue from former smokers with and without COPD. To identify potential pathobiological mechanisms that may link fetal lung, smoke exposure and adult lung disease, we study the interactions (physical and functional) of identified genes using protein-protein interaction networks.

RESULTS

We build IUS-exposure and COPD modules, which identify connected subnetworks linking fetal lung smoke exposure to adult COPD. Studying the relationships and connectivity among the different modules for fetal smoke exposure and adult COPD, we identify enriched pathways, including the AGE-RAGE and focal adhesion pathways.

CONCLUSIONS

The modules identified in our analysis add new and potentially important insights to understanding the early life molecular perturbations related to the pathogenesis of COPD. We identify AGE-RAGE and focal adhesion as two biologically plausible pathways that may reveal lung developmental contributions to COPD. We were not only able to identify meaningful modules but were also able to study interconnections between smoke exposure and lung disease, augmenting our knowledge about the fetal origins of COPD.

Adverse early-life environmental exposures and their repercussions on adult respiratory health

OBJECTIVE

To review in the literature the environmental problems in early life that impact the respiratory health of adults.

SOURCES

Non-systematic review including articles in English. Search filters were not used in relation to the publication date, but the authors selected mainly publications from the last five years.

SUMMARY OF THE FINDINGS

In this review, the authors present the exposure pathways and how the damage occurs depending on the child's stage of development; the authors describe the main environmental pollutants - tobacco smoke, particulate matter, air pollution associated with traffic, adverse childhood experiences and socioeconomic status; the authors present studies that evaluated the repercussions on the respiratory system of adults resulting from exposure to adverse environmental factors in childhood, such as increased incidence of Chronic Obstructive Pulmonary Disease (COPD), asthma and allergies; and, a decline in lung function. The authors emphasize that evidence demonstrates that adult respiratory diseases almost always have their origins in early life. Finally, the authors emphasize that health professionals must know, diagnose, monitor, and prevent toxic exposure among children and women.

CONCLUSION

The authors conclude that it is necessary to recognize risk factors and intervene in the period of greatest vulnerability to the occurrence of harmful effects of environmental exposures, to prevent, delay the onset or modify the progression of lung disease throughout life and into adulthood.

Preterm birth and the risk of chronic disease multimorbidity in adolescence and early adulthood: A population-based cohort study

BACKGROUND

People who were born prematurely have high risks of many individual diseases and conditions in the early part of the life course. However, our knowledge of the burden of multiple diseases (multimorbidity) among prematurely born individuals is limited. We aimed to investigate the risk and patterns of chronic disease multimorbidity in adolescence and early adulthood among individuals born across the spectrum of gestational ages, comparing preterm and full-term born individuals.

METHODS AND FINDINGS

We used individual-level data from linked nationwide registers to examine the associations of gestational age at birth with specialised healthcare records of ≥2 chronic diseases (multimorbidity) in adolescence (age 10-17 years) and early adulthood (age 18-30 years). Our study population comprised 951,116 individuals (50.2% females) born alive in Finland between 1st January 1987 and 31st December 2006, inclusive. All individuals were followed from age 10 years to the onset of multimorbidity, emigration, death, or 31 December 2016 (up to age 30 years). We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for multimorbidity using flexible parametric survival models. During 6,417,903 person-years at risk (median follow-up: 7.9 years), 11,919 individuals (1.3%) had multimorbidity in adolescence (18.6 per 10,000 person-years). During 3,967,419 person-years at risk (median follow-up: 6.2 years), 15,664 individuals (1.7%) had multimorbidity in early adulthood (39.5 per 10,000 person-years). Adjusted HRs for adolescent multimorbidity, comparing preterm to full-term born individuals, were 1.29 (95% CI: 1.22 to 1.36) and 1.26 (95% CI: 1.18 to 1.35) in females and males, respectively. The associations of preterm birth with early adult multimorbidity were less marked, with the adjusted HRs indicating 1.18-fold risk in females (95% CI: 1.12 to 1.24) and 1.10-fold risk in males (95% CI: 1.04 to 1.17). We observed a consistent dose-response relationship between earlier gestational age at birth and increasing risks of both multimorbidity outcomes. Compared to full-term born males, those born at 37-38 weeks (early term) had a 1.06-fold risk of multimorbidity in adolescence (95% CI: 0.98 to 1.14) and this risk increased in a graded manner up to 6.85-fold (95% CI: 5.39 to 8.71) in those born at 23-27 weeks (extremely premature), independently of covariates. Among females, the same risks ranged from 1.16-fold (95% CI: 1.09 to 1.23) among those born at 37-38 weeks to 5.65-fold (95% CI: 4.45 to 7.18) among those born at 23-27 weeks. The corresponding risks of early adult multimorbidity were similar in direction but less marked in magnitude, with little difference in risks between males and females born at 36-37 weeks but up to 3-fold risks observed among those born at 23-27 weeks.

CONCLUSIONS

Our findings indicate that an earlier gestational age at birth is associated with increased risks of chronic disease multimorbidity in the early part of the life course. There are currently no clinical guidelines for follow-up of prematurely born individuals beyond childhood, but these observations suggest that information on gestational age would be a useful characteristic to include in a medical history when assessing the risk of multiple chronic diseases in adolescent and young adult patients.

Focus on Early COPD: Definition and Early Lung Development

Chronic obstructive pulmonary disease (COPD) is a disease with high incidence rate and mortality rates worldwide. It is the third leading cause of death in the world. Nevertheless, little progress has been made in treating and preventing the disease. Under these circumstances, the concept of “early COPD” was proposed. Although this concept is not new, most health-care workers do not fully understand early COPD and tend to confuse it with mild COPD. In this review, we mainly discuss the definition of early COPD and the developmental trajectory of lung function. Although patients with early COPD have no symptoms, their lung function is already lower than that of normal people. A relatively complete definition is needed to identify this group of people. Reduced lung function is the diagnostic criterion for COPD, but lung development is a long-term dynamic process. In addition to smoking and air pollution, we should pay more attention to prenatal and childhood risk factors, for example, parents smoking, birth weight, preterm birth, mode of delivery, childhood respiratory infections and childhood asthma. Health-care workers need to be fully aware of early COPD, to reduce the morbidity of COPD and take effective measures to prevent these risk factors.

Childhood asthma : factors predicting severity and persistence of symptoms

BACKGROUND

Asthma is the most common chronic disease in infants. In young children, asthma still raises many questions and many points are still being debated.

AIM

The aim of this study is to identifies, in asthmatic children, factors predictors of severity and persistence of symptoms.

METHODS

A retrospective study of asthmatic infants<3 years enrolled in the pediatric department of Sfax over a period of 5 years (2007-2011). We were interested to social and environmental factors, the allergic background, clinical severity of the disease, results of allergic skin tests, treatment and respiratory outcome.

RESULTS

We collected 180 children with a sex ratio of 2.2. Family history of atopy and exposition to passive tobacco were noted in 45 % and 52% of cases respectively. The mean age of onset of wheezing was 6.6 months. Skin tests were positives in 32% of cases. At the time of diagnosis, asthma was classified intermittent (21%), mild to moderate (55.6%) and severe (22.2%).  Inhaled corticosteroids was initiated in 142 infants (78.8%). Skin tests performed in 84 patients, were positive in 32%. Factors associated with severe asthma were passive smoking, early age of onset, number of hospitalizations for exacerbation and existence of an aggravating factor. Factors predictors of persistence were an early age of onset, caesarean delivery, passive smoking and positive skin tests.

CONCLUSION

Factors associated with persistence of asthma at the individual level remains uncertain. However, atopy and passive smoking are major indicators.

Impact of prenatal and early life environmental exposures on normal human development

The global burden and pattern of disease has changed in recent decades, with fewer early childhood deaths and longer lives complicated by chronic disease. Disruption of normal human growth and development by adverse environmental exposures, especially during foetal development and early postnatal life increase life-long risk of chronic disease. The developmental timing and method of adverse exposure determines the likely impact on health and development. While many organ systems are structurally and functionally mature at birth, the CNS, respiratory and immune systems are not and undergo prolonged periods of postnatal growth and development. As such, these organ systems are vulnerable to adverse effects of both prenatal and postnatal environmental exposures. While the precise mechanisms underlying chronic disease are unknown, epigenetic mechanisms and the induction of oxidative stress are likely to be involved. An understanding of these processes is necessary to develop mitigation strategies aimed at reducing chronic disease prevalence.

Short- and Long-Term Complications of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a chronic lung disease most commonly seen in preterm infants of low birthweight who required postnatal respiratory support. Although overall incidence rates have not changed, recent advancements in medical care have resulted in lower mortality rates, and those affected are beginning to live longer. As a result, the long-term repercussions of BPD are becoming more apparent. Whereas BPD has been thought of as a disease of just the lungs, resulting in abnormalities such as increased susceptibility to pulmonary infections, impaired exercise tolerance, and pulmonary hypertension, the enduring complications of BPD have been found to extend much further. This includes an increased risk for cerebral palsy and developmental delays, lower intelligence quotient (IQ) scores, impaired executive functioning, behavioral challenges, delays in expressive and receptive language development, and an increased risk of growth failure. In addition, the deficits of BPD have been found to influence much more than just physical health; BPD survivors have been noted to have higher rates of health care use, starting with the initial hospitalization and continuing with therapy and specialist follow-up, as well as impairments in quality of life, both physical and psychological, that continue into adulthood. The long-term consequences of BPD may best be addressed through future research, including better understanding of the pathophysiologic mechanisms leading to BPD, further comparisons between newborns with BPD and those without, and long-term assessment and management of BPD patients as adults.

National and subnational trends of birthweight in Peru: Pooled analysis of 2,927,761 births between 2012 and 2019 from the national birth registry

Background

National and subnational characterization of birthweight profiles lacks in low- and middle-income countries, yet these are needed for monitoring the progress of national and global nutritional targets. We aimed to describe birthweight indicators at the national and subnational levels in Peru (2012-2019), and by selected correlates.

Methods

We studied mean birthweight (g), low birthweight (<2,500 g) and small for gestational age (according to international growth curves) prevalences. We analysed the national birth registry and summarized the three birthweight indicators at the national, regional, and province level, also by geographic area (Coast, Highlands, and Amazon). With individual-level data from the mother, we described the birthweight indicators by age, educational level and healthcare provider. Following an ecological approach (province level), we described the birthweight indicators by human development index (HDI), altitude above sea level, proportion of the population living in poverty and proportion of rural population.

Findings

Mean birthweight was always the lowest in the Highlands (2,954 g in 2019) yet the highest in the Coast (3,516 g in 2019). The same was observed for low birthweight and small for gestational age. In regions with Coast and Highlands, the birthweight indicators worsen from the Coast to the Highlands; the largest absolute difference in mean birthweight between Coast and Highlands in the same region was 367 g. All birthweight indicators were the worst in mothers with none/initial education, while they improved with higher HDI.

Interpretation

This analysis suggests that interventions are needed at the province level, given the large differences observed between Coast and Highlands even in the same region.

Funding

Wellcome Trust (214185/Z/18/Z).

Reduced Exercise Capacity in Adults Born Very Low Birth Weight: A Population-Based Cohort Study

RATIONALE

Population-based data regarding the consequences of very low birth weight (VLBW) and bronchopulmonary dysplasia (BPD) on adult exercise capacity is limited.

OBJECTIVES

To compare exercise capacity in a national VLBW cohort with term-born controls and explore factors contributing to the differences.

METHODS

At 26-30 years of age, 228 VLBW survivors and 100 controls underwent lung function tests, cardiopulmonary exercise testing and assessment of resting cardiac structure/function using echocardiography. Data on self-reported physical activity were collected.

MEASUREMENTS AND MAIN RESULTS

Compared with controls, VLBW adults demonstrated reduced oxygen uptake, work rate and oxygen pulse at peak exercise (9.3%, 10.7%, 10.8% lower, respectively) and earlier anaerobic threshold (all p<0.0001), with all mean values within normal range. VLBW survivors showed reduced physical activity, impaired lung function (reduced FEV1, FEV1/FVC, DLCO), altered left ventricular structure/function (reduced mass, size, stroke volume, cardiac output) and reduced right atrial/ventricular size. Adjustment for the combination of three sets of covariates (physical activity with BMI, lung function, cardiac structure/function) explained most of the exercise group-differences. Beyond the effects of physical activity and BMI, lung function and cardiac structure/function contributed approximately equally. BPD with other prematurity-related perinatal factors (ventilation, antenatal steroids, extremely low birth weight, extreme preterm) were not associated with a reduced exercise capacity.

CONCLUSIONS

Exercise capacity was significantly reduced in VLBW adults, which we speculate is from combined effects of impaired lung function, altered heart structure/function and reduced physical activity. Perinatal factors including BPD were not associated with a reduced exercise capacity.

The "Slow Horse Racing Effect" on Lung Function in Adult Life in Chronic Obstructive Pulmonary Disease Associated to Biomass Exposure

Although different trajectories in lung function decline have been identified in patients with COPD associated to tobacco exposure (TE-COPD), genetic, environmental, and infectious factors affecting lung function throughout life have not been fully elucidated in patients with COPD associated to biomass (BE-COPD). In this review, we present current epidemiological findings and notable advances in the natural history of lung decline in BE-COPD, as well as conditions modeling the FEV₁ trajectory, such as health insults, during the first years of childhood. Evidence shows that women exposed to biomass smoke reach adult life with a lower FEV₁ than expected. However, in contrast to the “horse racing effect” predicting an excessive lung-function decline in forthcoming years, as observed in smokers, this decline is slower in non-smokers, and no rapid decliners are observed. Accordingly, BE-COPD might be considered another phenotype of COPD based on assessments of lung function decline. Likewise, other functional and clinical aspects described in this review suggest that this condition might be similar to TE-COPD. More research is needed to fully characterize this subgroup of variants of COPD.

Epigenetic Changes Induced by Maternal Factors during Fetal Life: Implication for Type 1 Diabetes

Organ-specific autoimmune diseases, such as type 1 diabetes, are believed to result from T-cell-mediated damage of the target tissue. The immune-mediated tissue injury, in turn, is known to depend on complex interactions between genetic and environmental factors. Nevertheless, the mechanisms whereby environmental factors contribute to the pathogenesis of autoimmune diseases remain elusive and represent a major untapped target to develop novel strategies for disease prevention. Given the impact of the early environment on the developing immune system, epigenetic changes induced by maternal factors during fetal life have been linked to a likelihood of developing an autoimmune disease later in life. In humans, DNA methylation is the epigenetic mechanism most extensively investigated. This review provides an overview of the critical role of DNA methylation changes induced by prenatal maternal conditions contributing to the increased risk of immune-mediated diseases on the offspring, with a particular focus on T1D. A deeper understanding of epigenetic alterations induced by environmental stressors during fetal life may be pivotal for developing targeted prevention strategies of type 1 diabetes by modifying the maternal environment.

Childhood Origins of Adult Lung Disease as Opportunities for Prevention

Prenatal and childhood exposures have been shown to impact lung development, lung function trajectory, and incidence and prevalence of respiratory disease. Early life may serve as a window of susceptibility to such exposures, with the potential to influence lifelong respiratory health. Risk factors encountered in early life with potentially durable impact on lung health include prematurity, respiratory viral illness, allergen sensitization and exposure, tobacco use and exposure, indoor and outdoor pollution, diet, and obesity. These exposures vary in the extent to which they are modifiable, and interventions aimed at reducing harmful exposures range from individual-level behavior modification to policy initiatives implemented to promote population health. For many exposures, including tobacco-related exposures, multilevel interventions are needed. Future research is needed to provide insight as to early-life interventions to promote optimal lung growth and prevent development of chronic respiratory disease. Clinicians should play an active role, assisting individual patients in avoiding known detrimental exposures including maternal smoking during pregnancy and initiation of active smoking. Clinicians can be empowered by evidence to support policies promoting reduction of population-level risk factors, such as restriction on electronic cigarette sales and legislation to uphold air quality standards, to encourage attainment of maximal lung function and reduce risk of chronic lung disease.

More to Explore: Further Definition of Risk Factors for COPD - Differential Gender Difference, Modest Elevation in PM2.5, and e-Cigarette Use

Chronic obstructive pulmonary disease (COPD) is a severe respiratory disease with high morbidity and mortality, representing the third leading cause of death worldwide. Traditional risk factors for COPD include aging, genetic predisposition, cigarette smoking, exposure to environmental pollutes, occupational exposure, and individual or parental respiratory disease history. In addition, latest studies have revealed novel and emerging risk factors. In this review, differential gender difference as a factor for COPD development at different territories is discussed for the first time. First, women seem to have more COPD, while more women die of COPD or have more severe COPD, in Western societies. This seems different from the impression that COPD dominants in men, which is true in Eastern societies. It might be related to higher rate of cigarette smoking in women in developed countries (i.e., 12.0% of women in United States smoke vs. 2.2% in China). Nonetheless, women in Eastern societies are exposed to more biomass usage. Second, modest elevation in PM2.5 levels at >∼21.4-32.7 μg/m3, previously considered "cleaner air," is associated with incidence of COPD, indicating that more stringent goals should be set for the reduction of PM2.5 levels to prevent COPD development. Last but not least, e-cigarette use, which has become an epidemic especially among adolescents as officially declared by the United States government, has severe adverse effects that may cause development of COPD early in life. Built upon an overview of the established risk factors for COPD primarily focusing on cigarette smoking and environmental pollutions, the present review further discusses novel concepts, mechanisms, and solutions evolved around the emerging risk factors for COPD discussed above, understanding of which would likely enable better intervention of this devastating disease.

Gender differences in the associations of early onset poly tobacco and drug use prior to age 18 with the prevalence of adult bronchitis in the United States

PURPOSE

We investigated the associations of early onset polysubstance use prior to age 18 with the prevalence of bronchitis among U.S. adults and tested whether the associations differ by gender.

METHODS

A total of 77,950 adults, of them 2,653 with bronchitis in the past year, were from the combined 2013 and 2014 National Survey on Drug Use and Health data. The variable cluster analysis was used to classify nine variables about substance use prior to age 18 (cigarettes, cigars, smokeless tobacco, marijuana, cocaine, heroin, methamphetamines, ecstasy, and phencyclidine). Weighted multivariate logistic regression analysis (MLR) was used to examine the associations with bronchitis.

RESULTS

Nine variables were divided into two clusters: early onset poly tobacco use (three tobacco use variables) and early onset poly drug use (six drug use variables). The overall prevalence of bronchitis was 3.8% (5.1% for females and 2.3% for males). MLR analysis showed that being female, elderly (ages 65 and above), obese, and early onset poly tobacco use were associated with increased odds of bronchitis (p < 0.05). Gender-stratified analyses showed that early-onset poly tobacco use was significantly associated with bronchitis only in males, whereas early onset poly drug use was associated with bronchitis only in females. Moreover, obesity and tobacco use in the past year revealed associations with bronchitis regardless of gender.

CONCLUSIONS

Obesity, early onset poly tobacco use prior to age 18, and tobacco use in the past year were positively associated with bronchitis; furthermore, the associations of early onset polysubstance use with bronchitis differed by gender, which indicated that gender differences should be considered in developing effective prevention strategies.

The different phenotypes of COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with significant morbidity and mortality. To improve the health status and reduce symptom burden, it is important to identify a group of patients with similar characteristics and prognosis, called clinical phenotypes. Herein we shall review the different phenotypes of COPD.

SOURCES OF DATA

Keywords (COPD, phenotype, acute exacerbation) search was conducted in PubMed, Google Scholar.

AREAS OF AGREEMENT

Those with raised blood eosinophil counts respond better to steroid therapy at stable state and exacerbation.

AREAS OF CONTROVERSY

There is no universally accepted blood eosinophil cut-off value that will indicate favourable response to corticosteroids and potentially for future biologic therapy.

GROWING POINTS

There is an urgent need for further therapeutic options for COPD patients with non-eosinophilic inflammation.

AREAS TIMELY FOR DEVELOPING RESEARCH

Well-designed COPD trials with identification of phenotypes for more personalization of the treatment of COPD.

Loss of circadian protection against influenza infection in adult mice exposed to hyperoxia as neonates

Adverse early-life exposures have a lasting negative impact on health. Neonatal hyperoxia that is a risk factor for bronchopulmonary dysplasia confers susceptibility to influenza A virus (IAV) infection later in life. Given our previous findings that the circadian clock protects against IAV, we asked if the long-term impact of neonatal hyperoxia vis-à-vis IAV infection includes circadian disruption. Here, we show that neonatal hyperoxia abolishes the clock-mediated time of day protection from IAV in mice, independent of viral burden through host tolerance pathways. We discovered that the lung intrinsic clock (and not the central or immune clocks) mediated this dysregulation. Loss of circadian protein, Bmal1, in alveolar type 2 (AT2) cells recapitulates the increased mortality, loss of temporal gating, and other key features of hyperoxia-exposed animals. Our data suggest a novel role for the circadian clock in AT2 cells in mediating long-term effects of early-life exposures to the lungs.

Long and winding road: from infant wheeze to adult asthma

PURPOSE OF REVIEW

This review aims to recognize the multifactorial cause of asthma, from the influence of mother until adulthood, highlight the main characteristics of the disease at different ages and summarize the evidence of potential prevention strategies.

RECENT FINDINGS

To date, regarding the prenatal period, the presence of specific genes, maternal asthma, drugs, and tobacco exposure are the most relevant predisposing features for an asthmatic offspring. For newborns, preterm, bronchopulmonary dysplasia, and low birth weight has been associated with low lung function. Among young children, atopic dermatitis, lower respiratory tract infections, and increased levels of total Immunoglobulin E (IgE) and allergen-specific IgE are important determinants.Breastfeeding has been demonstrated being protective for the onset of asthma. Allergen immunotherapy has also been shown to have significant preventive effect decreasing asthma development. Inhaled corticosteroids use in early childhood prevents exacerbations but does not alter the natural history of asthma. Other interventions, such as the use of palivizumab, probiotics, vitamin D supplementation, and fish consumption presented controversial results.

SUMMARY

A good knowledge of risk factors for asthma development, from prenatal period to adulthood, may lead to efficacious preventive strategies. Further data of long-term follow-up in population-based studies according to different phenotypes are needed.

Telomere length shortening in hospitalized preterm infants: A pilot study

Leukocyte telomere length is a biomarker of aging-related health risks. Hospitalized preterm infants frequently experience elevated oxidative stress and inflammation, both of which contribute to telomere shortening. Our aim was to examine changes in telomere length during neonatal intensive care unit (NICU) hospitalization in a cohort of preterm infants <32 weeks' gestation. We conducted a longitudinal study of 10 infants (mean gestational age 27 weeks, range 23.5 to 29, at birth). We isolated DNA from dried blood spots and used Real Time Quantitative PCR to measure relative leukocyte telomere length in triplicate at three time points for each participant. From birth to discharge, infants experienced an average decline in relative telomere length of 0.021 units per week (95% CI -0.040, -0.0020; p = 0.03), after adjustment for gestational age at birth. Our results suggest a measurable decline in telomere length during NICU hospitalization. We speculate that telomere length change may convey information about NICU exposures that carry short- and long-term health risks.

DNA methylation perturbations may link altered development and aging in the lung

Fetal perturbations in DNA methylation during lung development may reveal insights into the enduring impacts on adult lung health and disease during aging that have not been explored altogether before. We studied the association between genome-wide DNA-methylation and post-conception age in fetal-lung (n=78, 42 exposed to in-utero-smoke (IUS)) tissue and chronological age in adult-lung tissue (n=160, 114 with Chronic Obstructive Pulmonary Disease) using multi-variate linear regression models with covariate adjustment and tested for effect modification by phenotypes. Overlapping age-associations were evaluated for functional and tissue-specific enrichment using the Genotype-Tissue-Expression (GTEx) project. We identified 244 age-associated differentially methylated positions and 878 regions overlapping between fetal and adult-lung tissues. Hyper-methylated CpGs (96%) were enriched in transcription factor activity (FDR adjusted P=2x10-33) and implicated in developmental processes including embryonic organ morphogenesis, neurogenesis and growth delay. Hypo-methylated CpGs (2%) were enriched in oxido-reductase activity and VEGFA-VEGFR2 Signaling. Twenty-one age-by-sex and eleven age-by-pack-years interactions were statistically significant (FDR<0.05) in adult-lung tissue. DNA methylation in transcription factors during development in fetal lung recapitulates in adult-lung tissue with aging. These findings reveal molecular mechanisms and pathways that may link disrupted development in early-life and age-associated lung diseases.

Early life exposures and risk of adult respiratory disease during 50 years of follow-up

Adult health is influenced by factors during fetal life affecting organ development and birth weight. We aimed to study such factors in relation to adult respiratory disease (ARD) risk. The Helsingborg Birth Cohort, Sweden, contributed baseline data collected by medical staff through clinical examination and questionnaires on maternal and birth characteristics 1964-1967. Register linkages were performed with completions of data on ARD by ICD 8-10 classifications (1969-2016), and/or ARD-related drug usage (2005-2016) enabling a 50-year follow-up time. Cox proportional hazard regression analyses were made to adjust for potential confounders, adjusted hazard ratio (aHR). A total of 3675 mothers and their offspring were included. Female offspring showed higher frequency of ARD than males, aHR 1.5 (95% CI 1.3-1.8). Maternal use of sedatives during second trimester, aHR 2.2 (95% CI 1.4-3.4), and maternal smoking during most of pregnancy, aHR 1.2 (95% CI 1.0-1.4), were associated with offspring ARD. Stratified by sex, large-for-gestational-age, aHR 1.4 (95% CI 1.0-1.9), was significantly associated with ARD in female offspring along with maternal sedative use during second trimester and maternal smoking during most of pregnancy. Maternal sedative use during second trimester or all trimesters were the only significant risk factors for male offspring. In conclusion, maternal sedative use in second trimester was independently associated with subsequent respiratory disease in adult offspring irrespective of sex.

Prenatal smoke exposure induces persistent Cyp2a5 methylation and increases nicotine metabolism in the liver of neonatal and adult male offspring

Prenatal smoke exposure (PSE) is a risk factor for nicotine dependence. One susceptibility gene for nicotine dependence is Cytochrome P450 (CYP) 2A6, an enzyme responsible for the conversion of nicotine to cotinine and nicotine clearance in the liver. Higher activity of the CYP2A6 enzyme is associated with nicotine dependence, but no research has addressed the PSE effects on the CYP2A6 gene or its mouse homologue Cyp2a5. We hypothesized that PSE affects Cyp2a5 promoter methylation, Cyp2a5 mRNA levels, and nicotine metabolism in offspring. We used a smoke-exposed pregnant mouse model. RNA, DNA, and microsomal protein were isolated from liver tissue of foetal, neonatal, and adult offspring. Enzyme activity, Cyp2a5 mRNA levels, and Cyp2a5 methylation status of six CpG sites within the promoter region were analysed via HPLC, RT-PCR, and bisulphite pyrosequencing. Our data show that PSE induced higher cotinine levels in livers of male neonatal and adult offspring compared to controls. PSE-induced cotinine levels in neonates correlated with Cyp2a5 mRNA expression and promoter methylation at CpG-7 and CpG+45. PSE increased methylation in almost all CpG sites in foetal offspring, and this effect persisted at CpG-74 in male neonatal and adult offspring. Our results indicate that male offspring of mothers which were exposed to cigarette smoke during pregnancy have a higher hepatic nicotine metabolism, which could be regulated by DNA methylation. Given the detected persistence into adulthood, extrapolation to the human situation suggests that sons born from smoking mothers could be more susceptible to nicotine dependence later in life.

Senescence in Pulmonary Fibrosis: Between Aging and Exposure

To date, chronic pulmonary pathologies represent the third leading cause of death in the elderly population. Evidence-based projections suggest that >65 (years old) individuals will account for approximately a quarter of the world population before the turn of the century. Genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication, are described as the nine “hallmarks” that govern cellular fitness. Any deviation from the normal pattern initiates a complex cascade of events culminating to a disease state. This blueprint, originally employed to describe aberrant changes in cancer cells, can be also used to describe aging and fibrosis. Pulmonary fibrosis (PF) is the result of a progressive decline in injury resolution processes stemming from endogenous (physiological decline or somatic mutations) or exogenous stress. Environmental, dietary or occupational exposure accelerates the pathogenesis of a senescent phenotype based on (1) window of exposure; (2) dose, duration, recurrence; and (3) cells type being targeted. As the lung ages, the threshold to generate an irreversibly senescent phenotype is lowered. However, we do not have sufficient knowledge to make accurate predictions. In this review, we provide an assessment of the literature that interrogates lung epithelial, mesenchymal, and immune senescence at the intersection of aging, environmental exposure and pulmonary fibrosis.

Characteristics of Patients with Chronic Obstructive Pulmonary Disease Exposed to Different Environmental Risk Factors: A Large Cross-Sectional Study

Purpose

Tobacco smoking, biomass smoke, and occupational exposure are the main risk factors for chronic obstructive pulmonary disease (COPD). The present study analyzes data on exposure to these factors in a cohort of patients with COPD and assesses their differences in demographic and clinical characteristics.

Patients and Methods

The cross-sectional observational study was conducted from November 2016 to December 2019. Inclusion criteria were patients aged over 40 years old with post-bronchodilator forced expiratory volume in 1 second (FEV₁)/forced vital capacity (FVC) <0.7. At baseline, demographic features and exposure history were recorded. Moreover, respiratory symptoms were assessed by the COPD Assessment Test (CAT) and modified Medical Research Council scale (mMRC). A generalized linear mixed model was used to adjust for potential confounders.

Results

A total of 5183 patients with COPD were included in the final analysis. The results demonstrate that exposure to tobacco combined with other risk factors resulted in significantly higher CAT scores (16.0 ± 6.7 vs 15.3 ± 6.3, P = 0.003) and more severe dyspnea (patients with mMRC ≥ 2, 71.5% vs 61.6%, P < 0.001) than exposure to tobacco alone. In addition, COPD patients with biomass smoke exposure alone had higher CAT scores than patients with only tobacco or occupational exposure (17.5 ± 6.3 vs 15.3 ± 6.3, and 15.2 ± 6.3, respectively, P < 0.05 for each comparison) and were more likely to be female and older. In addition, COPD patients who suffered from occupational exposure developed more severe dyspnea than those exposed to tobacco alone (70.8% vs 61.6%, P < 0.05), as did those exposed to biomass smoke alone (74.2% vs 61.6%, P < 0.05). This difference remained strong even after adjustment for potential confounders.

Conclusion

There are significant demographic and clinical differences among COPD patients with tobacco smoking, biomass smoke, and occupational exposures.

Co-methylation analysis in lung tissue identifies pathways for fetal origins of COPD

COPD likely has developmental origins; however, the underlying molecular mechanisms are not fully identified. Investigation of lung tissue-specific epigenetic modifications such as DNA methylation using network approaches might facilitate insights linking in utero smoke (IUS) exposure and risk for COPD in adulthood.We performed genome-wide methylation profiling for adult lung DNA from 160 surgical samples and 78 fetal lung DNA samples isolated from discarded tissue at 8-18 weeks of gestation. Co-methylation networks were constructed to identify preserved modules that shared methylation patterns in fetal and adult lung tissues and associations with fetal IUS exposure, gestational age and COPD.Weighted correlation networks highlighted preserved and co-methylated modules for both fetal and adult lung data associated with fetal IUS exposure, COPD and lower adult lung function. These modules were significantly enriched for genes involved in embryonic organ development and specific inflammation-related pathways, including Hippo, phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT), Wnt, mitogen-activated protein kinase and transforming growth factor-β signalling. Gestational age-associated modules were remarkably preserved for COPD and lung function, and were also annotated to genes enriched for the Wnt and PI3K/AKT pathways.Epigenetic network perturbations in fetal lung tissue exposed to IUS and of early lung development recapitulated in adult lung tissue from ex-smokers with COPD. Overlapping fetal and adult lung tissue network modules highlighted putative disease pathways supportive of exposure-related and age-associated developmental origins of COPD.

Sex-specific effects of in utero and adult tobacco smoke exposure

Tobacco smoke has harmful effects on a multiorgan level. Exposure to smoke, whether in utero or environmental, significantly increases susceptibility. This susceptibility has been identified to be divergent between males and females. However, there remains a distinct lack of thorough research into the relationship between sex and exposure to tobacco. Females tend to generate a more significant response than males during adulthood exposure. The intrauterine environment is meticulously controlled, and exposure to tobacco presents a significant factor that contributes to poor health outcomes and susceptibility later in life. Analysis of these effects in relation to the sex of the offspring is yet to be holistically reviewed and summarized. In this review, we will delineate the time-dependent relationship between tobacco smoke exposure and sex-specific disease susceptibility. We further outline possible biological mechanisms that may contribute to the identified pattern.

Respiratory Health of Pacific Youth: An Observational Study of Associated Risk and Protective Factors Throughout Childhood

BACKGROUND

Respiratory disease is the third most common cause of death in New Zealand, with Pacific people living in New Zealand bearing the greatest burden of this type of disease. Although some epidemiological outcomes are known, we lack the specifics required to formulate targeted and effective public health interventions. The Pacific Islands Families (PIF) birth cohort study is a study that provides a unique source of data to assess lung function and current respiratory health among participants entering early adulthood and to examine associations with early life events during critical periods of growth.

OBJECTIVE

This paper aims to provide an overview of the design, methods, and scope of the Respiratory Health of Pacific Youth Study, which uses the overall PIF study cohort aged 18-19 years.

METHODS

From 2000-2019, the PIF study has followed, from birth, the growth, and the development of 1398 Pacific children born in Auckland, New Zealand. Participants were nested within the overall PIF study (at ages 18-19 years) from June 2018, and assessments were undertaken until mid-November 2019. The assessments included respiratory and general medical histories, a general physical examination, assessment of lung function (forced expiratory volume and forced vital capacity), self-completed questionnaires (St George's Respiratory Questionnaire, European Quality of Life 5 Dimensions-3 Level, Epworth Sleepiness Scale for Children and Adolescents, and Leicester Cough Questionnaire), blood tests (eosinophils, Immunoglobulin E, Immunoglobulin G, Immunoglobulin A, Immunoglobulin M, and C-reactive protein), and chest x-rays. Noninferential analyses will be carried out on dimensionally reduced risk and protective factors and confounders.

RESULTS

Data collection began in June 2018 and ended in November 2019, with a total of 466 participants recruited for submission of the paper. Collection and collation of chest x-ray data is still underway, and data analysis and expected results will be published by November 2020.

CONCLUSIONS

This is the first longitudinal observational study to address the burden of respiratory disease among Pacific youth by determining factors in early life that impose long-term detriments in lung function and are associated with the presence of respiratory illness. Identifying risk factors and the magnitude of their effects will help in adopting preventative measures, establishing whether any avoidable risks can be modified by later resilient behaviors, and provide baseline measurements for the development of respiratory disease in later adult life. The study results can be translated into practice guidelines and inform health strategies with immediate national and international impact.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/18916.

COVID-19 Susceptibility in chronic obstructive pulmonary disease

In barely nine months, the pandemic known as COVID-19 has spread over 200 countries, affecting more than 22 million people and causing over than 786 000 deaths. Elderly people and patients with previous comorbidities such as hypertension and diabetes are at an increased risk to suffer a poor prognosis after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Although the same could be expected from patients with chronic obstructive pulmonary disease (COPD), current epidemiological data are conflicting. This could lead to a reduction of precautionary measures in these patients, in the context of a particularly complex global health crisis. Most COPD patients have a long history of smoking or exposure to other harmful particles or gases, capable of impairing pulmonary defences even years after the absence of exposure. Moreover, COPD is characterized by an ongoing immune dysfunction, which affects both pulmonary and systemic cellular and molecular inflammatory mediators. Consequently, increased susceptibility to viral respiratory infections have been reported in COPD, often worsened by bacterial co-infections and leading to serious clinical outcomes. The present paper is an up-to-date review that discusses the available research regarding the implications of coronavirus infection in COPD. Although validation in large studies is still needed, COPD likely increases SARS-CoV-2 susceptibility and increases COVID-19 severity. Hence, specific mechanisms to monitor and assess COPD patients should be addressed in the current pandemic.

Effects of mesenchymal stromal cell-conditioned media on measures of lung structure and function: a systematic review and meta-analysis of preclinical studies

BACKGROUND

Lung disease is a leading cause of morbidity and mortality. A breach in the lung alveolar-epithelial barrier and impairment in lung function are hallmarks of acute and chronic pulmonary illness. This review is part two of our previous work. In part 1, we demonstrated that CdM is as effective as MSCs in modulating inflammation. Herein, we investigated the effects of mesenchymal stromal cell (MSC)-conditioned media (CdM) on (i) lung architecture/function in animal models mimicking human lung disease, and (ii) performed a head-to-head comparison of CdM to MSCs.

METHODS

Adhering to the animal Systematic Review Centre for Laboratory animal Experimentation protocol, we conducted a search of English articles in five medical databases. Two independent investigators collected information regarding lung: alveolarization, vasculogenesis, permeability, histologic injury, compliance, and measures of right ventricular hypertrophy and right pulmonary pressure. Meta-analysis was performed to generate random effect size using standardized mean difference with 95% confidence interval.

RESULTS

A total of 29 studies met inclusion. Lung diseases included bronchopulmonary dysplasia, asthma, pulmonary hypertension, acute respiratory distress syndrome, chronic obstructive pulmonary disease, and pulmonary fibrosis. CdM improved all measures of lung structure and function. Moreover, no statistical difference was observed in any of the lung measures between MSCs and CdM.

CONCLUSIONS

In this meta-analysis of animal models recapitulating human lung disease, CdM improved lung structure and function and had an effect size comparable to MSCs.