Susceptible Young Adults and Development of COPD Later in Life.

RATIONALE: Chronic obstructive pulmonary disease (COPD) has its origin in early life, and the Global Initiative for Chronic Obstructive Lung Disease (GOLD) proposes a pre-disease state "pre-COPD". OBJECTIVE: We tested the hypothesis that susceptible young adults identified with chronic bronchitis and subtle lung function impairment will develop COPD later in life. METHODS: We followed random non-obstructive individuals aged 20-50years from two population-based cohorts from different smoking eras, the Copenhagen General Population Study from 2003(N=5497) and Copenhagen City Heart Study from 1976-78(N=2609), for 10 and 25years for development of COPD(forced expiratory volume in one second[FEV1]/forced vital capacity[FVC]<0.70) and COPD GOLD 2-4 (additionally FEV1<80% predicted). MEASUREMENTS AND MAIN RESULTS: After 10 years follow-up, 28% developed COPD and 13% COPD GOLD 2-4 in individuals susceptible to COPD compared to 8% and 1% in those without any susceptibility to COPD. Correspondingly, after 25years, 22% versus 13% developed COPD and 20% versus 8% developed COPD GOLD 2-4. More than half of incident COPD cases developed from a susceptible state. Compared to those without susceptibility to COPD, multivariable adjusted odds ratios in those susceptible to COPD were 3.42(95% confidence interval:2.78-4.21) for COPD and 10.1(6.77-15.2) for COPD GOLD 2-4 after 10years, and 1.54(1.23-1.93) and 2.12(1.64-2.73) after 25years. The ability of a COPD risk score consisting of the susceptibility state to COPD with smoking and asthma as risk factors to predict COPD later in life was high. CONCLUSIONS: Our study suggests the existence of a pre-disease state of COPD, which can be used for early identification of susceptible individuals at risk for COPD later in life.

Structural Predictors of Lung Function Decline in Young Smokers with Normal Spirometry.

Rationale: Chronic obstructive pulmonary disease (COPD) due to tobacco smoking commonly presents when extensive lung damage has occurred. Objectives: We hypothesized that structural change would be detected early in the natural history of COPD and would relate to loss of lung function with time. Methods: We recruited 431 current smokers (median age, 39 yr; 16 pack-years smoked) and recorded symptoms using the COPD Assessment Test (CAT), spirometry, and quantitative thoracic computed tomography (QCT) scans at study entry. These scan results were compared with those from 67 never-smoking control subjects. Three hundred sixty-eight participants were followed every six months with measurement of postbronchodilator spirometry for a median of 32 months. The rate of FEV1 decline, adjusted for current smoking status, age, and sex, was related to the initial QCT appearances and symptoms, measured using the CAT. Measurements and Main Results: There were no material differences in demography or subjective CT appearances between the young smokers and control subjects, but 55.7% of the former had CAT scores greater than 10, and 24.2% reported chronic bronchitis. QCT assessments of disease probability-defined functional small airway disease, ground-glass opacification, bronchovascular prominence, and ratio of small blood vessel volume to total pulmonary vessel volume were increased compared with control subjects and were all associated with a faster FEV1 decline, as was a higher CAT score. Conclusions: Radiological abnormalities on CT are already established in young smokers with normal lung function and are associated with FEV1 loss independently of the impact of symptoms. Structural abnormalities are present early in the natural history of COPD and are markers of disease progression. Clinical trial registered with www.clinicaltrials.gov (NCT03480347).

Type-2 inflammation and lung function decline in chronic airway disease in the general population.

BACKGROUND: It is unclear if type-2 inflammation is associated with accelerated lung function decline in individuals with asthma and chronic obstructive pulmonary disease (COPD). We tested the hypothesis that type-2 inflammation indicated by elevated blood eosinophils (BE) and fraction of exhaled nitric oxide (FeNO) is associated with accelerated lung function decline in the general population. METHODS: We included adults from the Copenhagen General Population Study with measurements of BE (N=15 605) and FeNO (N=2583) from a follow-up examination and assessed forced expiratory volume in 1 s (FEV1) decline in the preceding 10 years. Based on pre- and post-bronchodilator lung function, smoking history and asthma at follow-up examination, participants were assigned as not having airway disease, asthma with full reversibility (AR), asthma with persistent obstruction (APO), COPD, and not classifiable airflow limitation (NAL). RESULTS: FEV1 decline in mL/year increased with 1.0 (95% CI 0.6 to 1.4, p<0.0001) per 100 cells/µL higher BE and with 3.2 (95% CI 2.0 to 4.5, p<0.0001) per 10 ppb higher FeNO. Adjusted FEV1 decline in mL/year was 18 (95% CI 17 to 20) in those with BE<300 cells/µL and FeNO<20 ppb, 22 (19-25) in BE≥300 cells/µL or FeNO≥20 ppb, and 27 (21-33) in those with BE≥300 cells/µL and FeNO≥20 ppb (p for trend<0.0001). Corresponding FEV1 declines were 24 (19-29), 33 (25-40) and 44 (31-56) in AR (0.002), 26 (14-37), 36 (12-60) and 56 (24-89) in APO (0.07), 32 (27-36), 31 (24-38) and 44 (24-65) in COPD (0.46), and 27 (21-33), 35 (26-45), and 37 (25-49) in NAL (0.10), respectively. CONCLUSIONS: Type-2 inflammation indicated by elevated BE and FeNO is associated with accelerated FEV1 decline in individuals with chronic airway disease in the general population, and this association was most pronounced in an asthma-like phenotype.

Low smoking exposure and development and prognosis of COPD over four decades: A population-based cohort study.

A diagnosis of chronic obstructive pulmonary disease (COPD) is mainly considered in individuals with more than 10 pack-years of smoking. We tested the hypothesis that low smoking exposure, below the critical threshold of 10 pack-years, increases risk of COPD and leads to poor prognosis.We followed non-obstructive adult smokers from the Copenhagen City Heart Study for COPD, defined as forced expiratory volume in one second [FEV1]/forced vital capacity [FVC]<0.70 and FEV1<80% predicted, and for related clinical outcomes. First, we followed individuals for 5years according to baseline smoking for risk of developing COPD, and hereafter for up to four decades for severe exacerbations and death.In 6098 non-obstructive smokers, 1781(29%) developed COPD after 5 years follow-up; 23% in individuals with <10pack-years of smoking at baseline, 26% in those with 10-19.9pack-years, 30% in those with 20-39.9pack-years, and 39% in those with ≥40pack-years. During four decades follow-up, we recorded 620 exacerbations and 5573 deaths. Compared to individuals without COPD with <10pack-years of smoking, multivariable adjusted hazard ratios (HRs) for exacerbations were 1.94(95% confidence interval:1.36-2.77) in those without COPD with ≥10pack-years, 2.83(1.72-4.66) in those with COPD with <10pack-years, 4.34(2.93-6.43) in COPD with 10-19.9pack-years, 4.39(2.98-6.47) in COPD with 20-39.9pack-years, and 4.98(3.11-7.97) in COPD with ≥40pack-years. Corresponding HRs for all-cause mortality were 1.20(1.10-1.32), 1.33(1.14-1.56), 1.59(1.40-1.80),1.81(1.62-2.03), and 1.81(1.55-2.10), respectively.Low smoking exposure below the critical threshold of 10 pack-years increases risk of COPD in middle-aged adults within 5 years, and these individuals have increased risk of severe exacerbation and early death over four decades.

Advances in COPD imaging using CT and MRI: linkage with lung physiology and clinical outcomes.

Recent years have witnessed major advances in lung imaging in patients with COPD. These include significant refinements in images obtained by computed tomography (CT) scans together with the introduction of new techniques and software that aim for obtaining the best image whilst using the lowest possible radiation dose. Magnetic resonance imaging (MRI) has also emerged as a useful radiation-free tool in assessing structural and more importantly functional derangements in patients with well-established COPD and smokers without COPD, even before the existence of overt changes in resting physiological lung function tests. Together, CT and MRI now allow objective quantification and assessment of structural changes within the airways, lung parenchyma and pulmonary vessels. Furthermore, CT and MRI can now provide objective assessments of regional lung ventilation and perfusion, and multinuclear MRI provides further insight into gas exchange; this can help in structured decisions regarding treatment plans. These advances in chest imaging techniques have brought new insights into our understanding of disease pathophysiology and characterising different disease phenotypes. The present review discusses, in detail, the advances in lung imaging in patients with COPD and how structural and functional imaging are linked with common resting physiological tests and important clinical outcomes.

Housing conditions and risk of incident COPD: a Danish cohort study, 2000-2018.

BACKGROUND: More knowledge is needed on the risk of developing chronic obstructive pulmonary disease (COPD) associated with housing conditions and indoor environment based on cohort studies with a long follow-up time. OBJECTIVE: To examine the association between housing conditions and indoor environment and the risk of developing COPD. METHODS: In this cohort study, we followed 11,590 individuals aged ≥ 30 years free of COPD at baseline. Information on incident COPD and housing conditions and indoor environment was obtained from the Danish national registers and the Danish Health and Morbidity Survey year 2000. Poisson regression of incidence rates (IRs) were used to estimate incidence rate ratios (IRRs) of COPD. RESULTS: The overall IR of COPD was 8.6 per 1,000 person-years. Individuals living outside the biggest cities vs. living in the biggest cities (≥ 50,000) had a lower risk of COPD (200-4,999; IRR 0.77 (95% CI 0.65-0.90). Individuals living in semi-detached houses had a higher risk compared to individuals living in detached houses (IRR 1.29 (95% CI 1.07-1.55)). Likewise, individuals living in rented homes had a higher risk (IRR 1.47 (95% CI 1.27-1.70)) compared to individuals living in owned homes. The IR of COPD was 17% higher among individuals living in dwellings build > 1982 compared with individuals living in older dwellings (< 1962), not statistically significant though (IRR 0.83 (95% CI 0.68-1.03)). Likewise, the IR of COPD was 15% higher among individuals living in the densest households compared with individuals living in the least dense households, not statistically significant though (IRR 1.15 (95% CI 0.92-1.45)). This was primary seen among smokers. There was no difference in risk among individuals with different perceived indoor environments. Overall, similar patterns were seen when stratified by smoking status with exception of perceived indoor environment, where opposite patterns were seen for smokers and never smokers. CONCLUSION: Individuals living in semi-detached houses or rented homes had a higher risk of developing COPD compared to individuals living in detached or owned homes. Individuals living in cities with < 50.000 residents had a lower risk of COPD compared to individuals living in cities with ≥ 50.000 residents.

Bisoprolol in Patients With Chronic Obstructive Pulmonary Disease at High Risk of Exacerbation: The BICS Randomized Clinical Trial.

Importance: Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. Observational studies report that ß-blocker use may be associated with reduced risk of COPD exacerbations. However, a recent trial reported that metoprolol did not reduce COPD exacerbations and increased COPD exacerbations requiring hospital admission. Objective: To test whether bisoprolol decreased COPD exacerbations in people with COPD at high risk of exacerbations. Design, Setting, and Participants: The Bisoprolol in COPD Study (BICS) was a double-blind placebo-controlled randomized clinical trial conducted in 76 UK sites (45 primary care clinics and 31 secondary clinics). Patients with COPD who had at least moderate airflow obstruction on spirometry (ratio of forced expiratory volume in the first second of expiration [FEV1] to forced vital capacity <0.7; FEV1 <80% predicted) and at least 2 COPD exacerbations treated with oral corticosteroids, antibiotics, or both in the prior 12 months were enrolled from October 17, 2018, to May 31, 2022. Follow-up concluded on April 18, 2023. Interventions: Patients were randomly assigned to bisoprolol (n = 261) or placebo (n = 258). Bisoprolol was started at 1.25 mg orally daily and was titrated as tolerated during 4 sessions to a maximum dose of 5 mg/d, using a standardized protocol. Main Outcomes and Measures: The primary clinical outcome was the number of patient-reported COPD exacerbations treated with oral corticosteroids, antibiotics, or both during the 1-year treatment period. Safety outcomes included serious adverse events and adverse reactions. Results: Although the trial planned to enroll 1574 patients, recruitment was suspended from March 16, 2020, to July 31, 2021, due to the COVID-19 pandemic. Two patients in each group were excluded postrandomization. Among the 515 patients (mean [SD] age, 68 [7.9] years; 274 men [53%]; mean FEV1, 50.1%), primary outcome data were available for 514 patients (99.8%) and 371 (72.0%) continued taking the study drug. The primary outcome of patient-reported COPD exacerbations treated with oral corticosteroids, antibiotics, or both was 526 in the bisoprolol group, with a mean exacerbation rate of 2.03/y, vs 513 exacerbations in the placebo group, with a mean exacerbation rate of 2.01/y. The adjusted incidence rate ratio was 0.97 (95% CI, 0.84-1.13; P = .72). Serious adverse events occurred in 37 of 255 patients in the bisoprolol group (14.5%) vs 36 of 251 in the placebo group (14.3%; relative risk, 1.01; 95% CI, 0.62-1.66; P = .96). Conclusions and Relevance: Among people with COPD at high risk of exacerbation, treatment with bisoprolol did not reduce the number of self-reported COPD exacerbations requiring treatment with oral corticosteroids, antibiotics, or both. Trial Registration: isrctn.org Identifier: ISRCTN10497306.

Elevated Levels of Interleukin-1ß and Interleukin-10 Are Associated With Faster Lung Function Decline in People With Well-Treated Human Immunodeficiency Virus.

BACKGROUND: People with human immunodeficiency virus (PWH) have an increased risk of chronic lung diseases and chronic inflammation. We aimed to investigate if inflammatory markers and monocyte activation are associated with faster lung function decline in PWH. METHODS: We included 655 PWH from the Copenhagen Comorbidity in HIV Infection (COCOMO) Study. Eligible participants were aged ≥25 years and had 2 spirometries separated by >2 years. Inflammatory markers (interleukin [IL]-1ß, IL-2, IL-6, IL-10, tumor necrosis factor-α, and interferon-γ) were measured at baseline by Luminex, and soluble CD14 and soluble CD163 by enzyme-linked immunosorbent assay. Using linear mixed models, we investigated whether elevated cytokine levels were associated with faster lung function decline. RESULTS: The majority of PWH were males (85.2%) with undetectable viral replication (95.3%). We found a faster decline in forced expiratory volume in 1 second (FEV1) in PWH with elevated IL-1ß and IL-10, with an additional decline of 10.3 mL/year (95% confidence interval [CI], 2.1-18.6; P = .014) and 10.0 mL/year (95% CI, 1.8-18.2; P = .017), respectively. We found no interaction between smoking and IL-1ß or IL-10 on FEV1 decline. CONCLUSIONS: Elevated IL-1ß and IL-10 were independently associated with faster lung function decline in PWH, suggesting that dysregulated systemic inflammation may play a role in the pathogenesis of chronic lung diseases.

Faster lung function decline in people living with HIV despite adequate treatment: a longitudinal matched cohort study.

INTRODUCTION: Chronic lung disease is common among people living with HIV (PLWH). We hypothesised that PLWH receiving antiretroviral therapy (ART) have faster lung function decline than matched controls. METHODS: We performed a prospective matched cohort study by including ART-treated PLWH from the Copenhagen Co-morbidity in HIV Infection Study (n=705) and the INSIGHT Strategic Timing of Antiretroviral Treatment Pulmonary Substudy (n=425) and frequency matched population controls from the Copenhagen General Population Study (n=2895) in a 1:3 ratio. Eligible participants were ≥25 years old and had two spirometry tests separated by at least 2 years of follow-up. Forced expiratory volume in 1 s (FEV1) decline (mL/year) was compared between PLWH and controls using a linear mixed model adjusted for age, sex, ethnicity and smoking status. Effect modification by smoking was investigated in subgroup analyses. RESULTS: The majority of PLWH were virally suppressed (96.1%). The adjusted mean annual decline in FEV1 was faster in PLWH than in controls with 36.4 (95% CI 33.7 to 39.1) vs 27.9 (95% CI 26.9 to 28.8) mL/year, yielding a difference of 8.5 (95% CI 5.6 to 11.4) mL/year. The association between HIV and FEV1 decline was modified by smoking, with the largest difference in current smokers (difference: 16.8 (95% CI 10.5 to 23.0) mL/year) and the smallest difference in never-smokers (difference: 5.0 (95% CI 0.7 to 9.3) mL/year). FEV1 decline >40 mL/year was more prevalent in PLWH (adjusted OR: 1.98 (95% CI 1.67 to 2.34)). CONCLUSION: Well-treated PLWH have faster lung function decline than controls and smoking seems to modify this association, suggesting that smoking may lead to more rapid lung function decline in PLWH than in controls.

Fibrin degradation products and survival in patients with chronic obstructive pulmonary disease: a protocolized prospective observational study.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) have a high incidence of cardiovascular disease including thromboembolisms. Fibrin degradation products, like D-dimer, have been associated with death from all causes in healthy individuals and COPD patients. We aimed to determine the (i) association between D-dimer levels and all-cause mortality and time being alive and out of a hospital, (ii) possible modifying effect of anticoagulant treatment,, and (iii) distribution of D-dimer in patients with moderate to severe COPD. METHODS: Results of routinely measured stable phase D-dimer samples from COPD-outpatients at Copenhagen University Hospital - Herlev and Gentofte, COPD-outpatient clinic were collected using the Danish registries. These were used to examine whether COPD-patients with a D-dimer level in the upper quartile, had a higher risk of death from all causes within 365 days. RESULTS: In the unadjusted Cox proportional hazards regression we found an association between high D-dimer and all-cause mortality: Hazard ratio (HR): 2.3 (95% Confidence Interval (CI) 1.1-4.7). In the fully adjusted regression, the HR was 1.8 (CI 0.8-3.9). We did not find any interaction between D-dimer and anticoagulant or antiplatelet therapy. For the secondary outcome, proportion of days alive and out of hospital in 365 days (pDAOH), the unadjusted multiple linear regression had an association between high D-dimer level and pDAOH: -2.7% points (pp) (CI -3.9 pp - -1.5 pp), which was attenuated to -1,7pp (-2.9pp - -0.4pp) in the fully adjusted regression. CONCLUSIONS: In patients with moderate to severe COPD, patients with a high level of D-dimer were more likely to die; however, the signal was not strong in the adjusted analyses and our results do not support unselected risk stratification with D-dimer in COPD-outpatients.

Prognosis of Patients with Chronic Obstructive Pulmonary Disease Not Eligible for Major Clinical Trials.

Rationale: Randomized controlled trials only include a subset of patients with chronic obstructive pulmonary disease (COPD) fulfilling strict inclusion criteria. Thus, most patients with COPD in a real-world setting do not have the necessary evidence to support treatment effectiveness. Objectives: To test the hypotheses that most individuals with COPD in the general population are not represented in major clinical trials despite clinically significant disease with exacerbations and early death. Methods: In 105,630 adults from a Danish contemporary population-based cohort, we defined COPD as age 40 or more years, chronic respiratory symptoms, history of smoking exposure, and airflow limitation with FEV1/FVC < 0.70. Outcomes included acute exacerbations and all-cause mortality. Symptomatic smokers without COPD were used as a reference group. Measurements and Main Results: Of all, 7,516 (7%) and 16,079 (15%) were symptomatic smokers with and without COPD. Only 44% of those with COPD were eligible for major clinical trials when applying FEV1 < 80% predicted, smoking history of 10 or more pack-years, and no comorbid asthma as common inclusion criteria. During the median 8.9 years of follow-up, we observed 2,130 acute exacerbations and 3,973 deaths in symptomatic smokers. Compared with symptomatic smokers without COPD, multivariable-adjusted hazard ratios for exacerbations were 7.45 (95% confidence interval, 5.41-10.3) and 29.0 (21.1-39.8) in those with COPD, respectively, excluded and eligible for clinical trials. Corresponding hazard ratios for all-cause mortality were 1.21 (1.11-1.31) and 1.67 (1.54-1.81), respectively. Conclusions: More than half of individuals with COPD in the general population are excluded from major clinical trials; however, these individuals have a clinically significant disease with exacerbations and early death compared with symptomatic smokers without COPD.

International Differences in the Frequency of Chronic Obstructive Pulmonary Disease Exacerbations Reported in Three Clinical Trials.

Rationale: Exacerbations of chronic obstructive pulmonary disease (COPD) are an important endpoint in multinational clinical treatment trials, but the observed event rate is often lower than anticipated and appears to vary between countries. Objectives: We investigated whether systematic differences in national exacerbation rates might explain this observed variation. Methods: We reviewed data from three large multicenter international randomized trials conducted over an 18-year period with different designs and clinical severities of COPD, comparing bronchodilator and/or inhaled corticosteroids with bronchodilators alone and/or placebo. Exacerbations were defined by antibiotic and/or oral corticosteroid use (moderate) or need for hospitalization (severe). We calculated crude exacerbation rates in the 30 countries contributing 30 or more patients to at least two trials. We grouped data by exacerbation rate based on their first study contribution. Measurements and Main Results: For the 29,756 patients in 41 countries analyzed, the mean exacerbation rate was two- to threefold different between the highest and lowest tertiles of the recruiting nations. These differences were not explained by demographic features, study protocol, or reported exacerbation history at enrollment. Of the 18 countries contributing to all trials, half of those in the highest and half in the lowest tertiles of exacerbation history remained in these groups across trials. Severe exacerbations showed a different rank order internationally. Conclusions: Countries contributing to COPD trials differ consistently in their reporting of healthcare-defined exacerbations. These differences help explain why large studies have been needed to show differences between treatments that decrease exacerbation risk.

Treatment Trials in Young Patients with Chronic Obstructive Pulmonary Disease and Pre-Chronic Obstructive Pulmonary Disease Patients: Time to Move Forward.

Chronic obstructive pulmonary disease (COPD) is the end result of a series of dynamic and cumulative gene-environment interactions over a lifetime. The evolving understanding of COPD biology provides novel opportunities for prevention, early diagnosis, and intervention. To advance these concepts, we propose therapeutic trials in two major groups of subjects: "young" individuals with COPD and those with pre-COPD. Given that lungs grow to about 20 years of age and begin to age at approximately 50 years, we consider "young" patients with COPD those patients in the age range of 20-50 years. Pre-COPD relates to individuals of any age who have respiratory symptoms with or without structural and/or functional abnormalities, in the absence of airflow limitation, and who may develop persistent airflow limitation over time. We exclude from the current discussion infants and adolescents because of their unique physiological context and COPD in older adults given their representation in prior randomized controlled trials (RCTs). We highlight the need of RCTs focused on COPD in young patients or pre-COPD to reduce disease progression, providing innovative approaches to identifying and engaging potential study subjects. We detail approaches to RCT design, including potential outcomes such as lung function, patient-reported outcomes, exacerbations, lung imaging, mortality, and composite endpoints. We critically review study design components such as statistical powering and analysis, duration of study treatment, and formats to trial structure, including platform, basket, and umbrella trials. We provide a call to action for treatment RCTs in 1) young adults with COPD and 2) those with pre-COPD at any age.

Trends in smoking-related diseases by socioeconomic position following a national smoking ban in 2007: a nationwide study in the Danish population.

BACKGROUND: National comprehensive smoke-free legislation has been found to decrease the incidence of several smoking-related diseases. In 2007, Denmark introduced a national smoking ban, which banned smoking indoor in workplaces and public places, although only partial restrictions were applied in certain settings. We examined the impact of the smoking ban on smoking-related diseases and whether this differed across socioeconomic groups. METHODS: Interrupted time series analyses of nationwide register data were performed using Poisson regression models to examine the differential impact of the smoking ban on monthly incidence rates of acute myocardial infarction, chronic obstructive pulmonary disease, and smoking-related cancers from 2002 to 2015. Immediate changes in incidence rates after the smoking ban and long-term changes in disease trends were estimated by comparing data from the pre- and post-ban period. Models were stratified by socioeconomic position. RESULTS: Overall, we found neither immediate changes in rates of acute myocardial infarction, chronic obstructive pulmonary disease, and smoking-related cancers following the smoking ban nor long-term post-ban changes in disease trends as compared to before the ban. Results did not differ across socioeconomic groups. A pronounced socioeconomic gradient in incidence rates was observed for all outcomes both before and after the smoking ban. CONCLUSION: The national smoking ban was not associated with a lower incidence of smoking-related diseases in the post-ban period compared to pre-ban levels and no differences between socioeconomic groups were observed. Future tobacco control in Denmark should consider which measures most effectively target the low socioeconomic groups to decrease the current strong socioeconomic inequality in health.

The environmental impact of inhaled therapy: making informed treatment choices.

When selecting the best inhaler and drug combination for a patient with respiratory disease, a number of factors should be considered. While efficacy and safety of medical treatments are always a priority, in recent years the environmental impacts of all aspects of life have become an increasingly necessary consideration and inhaled therapies are no exception. The carbon footprint of an item, individual or organisation is one of the most important and quantifiable environmental impacts, assessed by the amount of greenhouse gases (often expressed in terms of carbon dioxide equivalents) generated throughout the life cycle. The two most commonly prescribed and manufactured inhaler types worldwide are pressurised metered-dose inhalers (pMDIs) containing hydrofluorocarbon (HFC) propellants and dry powder inhalers (DPIs). Most of the carbon footprint of current pMDIs is a result of the propellants that they contain (HFC-134a and HFC-227ea, which are potent greenhouse gases). In comparison, the powder in DPIs is dispersed by the patient's own inhalation, meaning DPIs do not contain a propellant and have a lower carbon footprint than most pMDIs currently available. Soft mist inhalers are another propellant-free option: the device contains a spring, which provides the energy to disperse the aqueous medication. In this review, we examine the published data on carbon footprint data for inhalers, providing an analysis of potential implications for treatment decision making and industry initiatives.

ERS statement: a core outcome set for clinical trials evaluating the management of COPD exacerbations.

Clinical trials evaluating the management of acute exacerbations of COPD assess heterogeneous outcomes, often omitting those that are clinically relevant or more important to patients. We have developed a core outcome set, a consensus-based minimum set of important outcomes that we recommend are evaluated in all future clinical trials on exacerbations management, to improve their quality and comparability. COPD exacerbations outcomes were identified through methodological systematic reviews and qualitative interviews with 86 patients from 11 countries globally. The most critical outcomes were prioritised for inclusion in the core outcome set through a two-round Delphi survey completed by 1063 participants (256 patients, 488 health professionals and 319 clinical academics) from 88 countries in five continents. Two global, multi-stakeholder, virtual consensus meetings were conducted to 1) finalise the core outcome set and 2) prioritise a single measurement instrument to be used for evaluating each of the prioritised outcomes. Consensus was informed by rigorous methodological systematic reviews. The views of patients with COPD were accounted for at all stages of the project. Survival, treatment success, breathlessness, quality of life, activities of daily living, the need for a higher level of care, arterial blood gases, disease progression, future exacerbations and hospital admissions, treatment safety and adherence were all included in the core outcome set. Focused methodological research was recommended to further validate and optimise some of the selected measurement instruments. The panel did not consider the prioritised set of outcomes and associated measurement instruments to be burdensome for patients and health professionals to use.

Plasma immunoglobulin E and risk of exacerbation and mortality in chronic obstructive pulmonary disease: A contemporary population-based cohort.

BACKGROUND: Novel biomarkers and targeted treatments are needed for patients with chronic obstructive pulmonary disease (COPD). OBJECTIVE: To test the hypothesis that high plasma immunoglobulin (Ig)E concentrations associate with increased risk of exacerbation and mortality in individuals with COPD in the general population. METHODS: Among 46,598 adults in the Copenhagen General Population Study, we included 1559 with COPD, defined as forced expiratory volume in 1 second/forced vital capacity < 0.70 and forced expiratory volume in 1 second < 80% predicted in individuals aged ≥ 40 years with chronic respiratory symptoms and smoking exposure ≥ 10 pack-years, and without asthma. We assessed risk of future severe exacerbation and all-cause mortality according to baseline plasma IgE ≥ 76 IU/mL, a clinical cutoff for omalizumab treatment in severe asthma. RESULTS: During 14 years of follow-up (median, 6.9; interquartile range, 3.4), we recorded 224 severe exacerbations and 434 deaths in 1559 individuals with COPD. Individuals with COPD with IgE ≥ 76 IU/mL vs those with < 76 IU/mL had a multivariable adjusted hazard ratio (HR) of 1.43 (95% confidence interval, 1.07-1.89) for severe exacerbation and 1.30 (1.05-1.62) for all-cause mortality. Compared with individuals with IgE < 76 IU/mL and blood eosinophils < 300 cells/µL, the multivariable adjusted HR for severe exacerbation was 1.12 (0.76-1.67) for those with IgE < 76 IU/mL and blood eosinophils ≥ 300 cells/µL, 1.62 (1.17-2.24) for IgE ≥ 76 IU/mL and blood eosinophils < 300 cells/µL, and 1.06 (0.63-1.77) for those with IgE ≥ 76 IU/mL and blood eosinophils ≥ 300 cells/µL. Corresponding HRs for all-cause mortality were 1.27 (0.99-1.63), 1.47 (1.14-1.88), and 1.17 (0.83-1.64), respectively. CONCLUSION: High plasma IgE was associated with an increased risk of severe exacerbation and all-cause mortality in individuals with COPD in the general population, independent of blood eosinophils.

Trajectory of Preserved Ratio Impaired Spirometry: Natural History and Long-Term Prognosis.

Rationale: Natural history of preserved ratio impaired spirometry (PRISm), often defined as FEV1/FVC ⩾lower limit of normal and FEV1 <80% of predicted value, is not well described. Objectives: To investigate the natural history and long-term prognosis of the following PRISm trajectories: persistent PRISm trajectory (individuals with PRISm both young and middle-aged), normal to PRISm trajectory (individuals developing PRISm from normal spirometry in young adulthood), and PRISm to normal trajectory (individuals recovering from PRISm in young adulthood by normalizing spirometry while middle-aged). Methods: We followed 1,160 individuals aged 20-40 years from the Copenhagen City Heart Study from 1976 to 1983 until 2001 to 2003 to determine their lung function trajectory; 72 had persistent PRISm trajectory, 76 had normal to PRISm trajectory, 155 had PRISm to normal trajectory, and 857 had normal trajectory. From 2001-2003 until 2018, we determined the risk of cardiopulmonary disease and death. Measurements and Main Results: We recorded 198 admissions for heart disease, 143 for pneumonia, and 64 for chronic obstructive pulmonary disease as well as 171 deaths. Compared with individuals with normal trajectory, hazard ratios for individuals with persistent PRISm trajectory were 1.55 (95% confidence interval, 0.91-2.65) for heart disease admission, 2.86 (1.70-4.83) for pneumonia admission, 6.57 (3.41-12.66) for chronic obstructive pulmonary disease admission, and 3.68 (2.38-5.68) for all-cause mortality. Corresponding hazard ratios for individuals with normal to PRISm trajectory were 1.91 (1.24-2.95), 2.74 (1.70-4.42), 7.61 (4.21-13.72), and 2.96 (1.94-4.51), respectively. Prognosis of individuals with PRISm to normal trajectory did not differ from those with normal trajectory. Conclusions: PRISm in middle-aged individuals is associated with increased risk of cardiopulmonary disease and all-cause mortality, but individuals who recover from PRISm during their adult life are no longer at increased risk.

Importance of Early COPD in Young Adults for Development of Clinical COPD: Findings from the Copenhagen General Population Study.

Rationale: Individuals who will develop chronic obstructive pulmonary disease (COPD) could be identified at an early age before clinical manifestations appear. Objectives: We investigated risk of clinical COPD 10 years later in young adults from the general population with and without early COPD with a focus on smoking exposure. Methods: We included 14,870 individuals aged 20-100 years from the Copenhagen General Population Study with spirometry 10 years apart. Early COPD was defined as baseline FEV1/FVC less than the lower limit of normal in individuals aged <50 years. Outcomes included clinical COPD at final examination 10 years later (chronic respiratory symptoms with FEV1/FVC <0.70 and FEV1 <80% predicted) and acute exacerbation hospitalizations during follow-up. Measurements and Main Results: Among 5,497 individuals aged <50 years at baseline with FEV1/FVC ≥0.70, 104 (3%) developed clinical COPD 10 years later; 4% of smokers with ≥10 pack-years had early COPD; 3% of smokers with <10 pack-years had early COPD; and 2% of never-smokers had early COPD. Among smokers with ≥10 pack-years, 24% developed clinical COPD in those with early COPD versus 4% in those without early COPD. Corresponding numbers were 10% and 1% in smokers with <10 pack-years and 3% and <1% in never-smokers, respectively. Among individuals with early COPD, odds ratios for clinical COPD 10 years later were 7.77 (95% confidence interval [CI], 4.10-14.7) in smokers with ≥10 pack-years and 8.56 (95% CI, 4.92-14.9) in all smokers, whereas hazard ratios for acute exacerbation hospitalizations were 4.16 (95% CI, 1.66-10.5) and 4.33 (95% CI, 1.89-9.93), respectively. Results were validated in the Copenhagen City Heart Study. Conclusions: Depending on amount of smoking exposure, <24% of young adults in the general population with early COPD develop clinical COPD 10 years later. A smoking exposure threshold for early COPD should be reconsidered, as younger individuals are less represented in those with high smoking exposure.

Pharmacotherapy and Lung Function Decline in Patients with Chronic Obstructive Pulmonary Disease. A Systematic Review.

Rationale: Whether pharmacological therapy alters decline in FEV1 in chronic obstructive pulmonary disease remains controversial. Because pharmacotherapy improves health status, exacerbation rate, and symptoms, it may be unethical to complete placebo-controlled long-term studies aimed at modifying FEV1 decline.Objectives: We conducted a systematic review of placebo-controlled pharmacological trials lasting ≥1 year to address the question of whether therapy alters FEV1 decline.Methods: A literature search for randomized trials that included repeated spirometry with at least one active and one placebo arm was conducted. Articles were excluded if study duration was <1 year, <3 spirometric measurements, or <100 subjects per arm. Study design was assessed using the Jadad score. To combine studies and find the estimated effect, we used random effects methodology to account for both within-study and between-study variation.Measurements and Main Results: There were 33,051 patients in the analysis (active component, n = 21,941; placebo, n = 11,110 in nine studies). The active treatment arms demonstrated a 5.0 ml/yr reduction (95% confidence interval, 0.8-9.1 ml/yr; P < 0.001) in the rate of FEV1 decline compared with the placebo arms. The relative FEV1 differences between active and placebo arms were within the range of differences reported for health status and for the exacerbation rate in the same studies.Conclusions: In chronic obstructive pulmonary disease, pharmacotherapy ameliorates rate of lung function decline. The relative benefit observed is within the range of those reported for health status and exacerbations in the same studies. Guidelines should be adjusted according to these findings.