Natural history of COPD: Focusing on change in FEV1

Risk factors for Pseudomonas aeruginosa isolation in chronic obstructive pulmonary disease: a systematic review and meta-analysis

BACKGROUND

Pseudomonas aeruginosa (PA) isolation in patients with chronic obstructive pulmonary disease (COPD) has been associated with a poor prognosis. This meta-analysis aimed to determine significant risk factors for PA isolation among patients with COPD.

METHODS

A systematic literature retrieval from PubMed, Embase, Web of Science and China National Knowledge Infrastructure (CNKI) was conducted, including studies from January 2003 to September 2024. Case-control and cohort studies exploring the risk factors for PA isolation in patients with COPD were included in this analysis. A random-effects model was applied to estimate the pooled adjusted odds ratio (paOR) or hazard ratio (paHR) with the corresponding 95% confidence intervals (CI).

RESULTS

Thirteen eligible studies with a total of 25,802 participants were included in this meta-analysis. Prior systemic steroid therapy (paOR: 2.67; 95% CI: 1.29-5.53; P = 0.008), previous antibiotic treatment (paOR: 2.83; 95% CI: 1.14-6.97; P = 0.02), high "Body mass index, airflow Obstruction, Dyspnea, Exercise capacity" (BODE) index (paOR: 4.13; 95% CI: 1.67-10.23; P = 0.002), 6-min walking distance (6MWD) < 250 m (paOR: 4.27; 95% CI: 2.59-7.01; P < 0.001), COPD assessment test (CAT) score > 20 points (paOR: 2.49; 95% CI: 1.46-4.23; P = 0.001), hypoproteinemia (paOR: 2.62; 95%CI: 1.32-5.19; P = 0.006), hospitalizations in the previous year (paOR: 3.74; 95%CI: 1.22-11.49; P = 0.021), Bronchiectasis (paOR = 4.81; 95% CI: 3.66-6.33; P < 0.001) and prior PA isolation (paOR: 16.39; 95% CI: 7.65-35.10; P < 0.001) were associated with PA isolation in patients with COPD.

CONCLUSIONS

Our study identified nine risk factors associated with an increased risk of PA isolation in COPD patients. These findings are significant for the early identification of patients at risk for PA isolation, which might contribute to reducing mortality and improving clinical outcomes.

SPECT/CT to quantify early small airway disease and its relationship to clinical symptoms in smokers with normal lung function: a pilot study

Introduction

Smokers frequently display respiratory symptoms despite the fact that their pulmonary function tests (PFTs) can be normal. Quantitative lung ventilation single-photon emission computed tomography (SPECT/CT) can provide a quantification of lung ventilatory homogeneity and could prove useful as an early marker of airway disease in smokers. We measured the effects of smoking on regional ventilation distribution in subjects with normal lung function and evaluated whether ventilation distribution in these subjects is related to lung function tests results and clinical symptoms.

Methods

Subjects without any history of respiratory disease were prospectively recruited and separated in two groups: active smokers (AS: ≥10 cigarettes/day and history of ≥15 pack-years) and never smokers (NS: lifetime exposure of <5 cigarettes). All subjects performed PFTs (which had to be normal, defined as z-score values of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio, total lung capacity (TLC) residual volume and diffusion capacity (DLCO) all falling between -1.65 and +1.65) and underwent SPECT/CT with Technegas, which generated subject- specific ventilation heterogeneity maps. The area under the compensated coefficient of variation (CV) density curve for CV values > 40%, (AUC-CV40%) was used as the measure of ventilation heterogeneity.

Results

30 subjects were recruited (15 per group). Subjects in the AS group displayed higher dyspnea levels (1 [1-2] vs. 0 [0-1] units on mMRC scale, p < 0.001). AUC- CV40% was significantly higher in the AS group (0.386 ± 0.106 vs. 0.293 ± 0.069, p = 0.004). AUC-CV40% was significantly correlated to FEV1 (rho = -0.47, p = 0.009), DLCO (rho = -0.49, p = 0.006), CAT score (rho = 0.55, p = 0.002) and mMRC score (rho = 0.54, p = 0.002). Subjects with mMRC >0 had higher AUC-CV40% values than those without dyspnea (0.289 ± 0.071 vs. 0.378 ± 0.102, p = 0.006), while FEV1 and DLCO were not different between those groups. ROC analyses showed that the AUC for AUC-CV40% in identifying subjects with mMRC score >0 was 0.78 (95%CI 0.61-0.95, p = 0.009), which was significantly higher than that of FEV1 and DLCO.

Discussion

In smokers with normal lung function, ventilatory inhomogeneities can be quantified using SPECT/CT. AUC-CV40% values are related to lung function decline and to respiratory symptomatology, suggesting a potential role for this marker in the evaluation of symptomatic smokers.

Effects of different traditional Chinese exercises on pulmonary function in patients with stable chronic obstructive pulmonary disease: a network meta-analysis

OBJECTIVE

Traditional Chinese exercises (Taichi, Wuqinxi, Liuzijue, and Baduanjin) are considered effective alternative treatments for improving symptoms in the stable phase of COPD. However, the most effective exercise remains unknown. This study compared the effectiveness of different traditional Chinese exercises on pulmonary function in patients with stable chronic obstructive pulmonary disease (COPD) using a network meta-analysis.

METHODS

From database establishment until September 2023, eligible randomized controlled trials (RCTs) were searched. Two reviewers performed the risk of bias assessment of the included studies using the Cochrane Collaboration tool, and the evidence level was suggested using the GRADE system.

RESULTS

Fifty-seven studies comprising 4294 patients were included. The results of the network meta-analysis show that Baduanjin was most effective in improving the forced expiratory volume in the first second (FEV1). However, Liuzijue significantly improved the first-second forced vital capacity percentage of expected value (FEV1%) and the ratio of the forced expiratory volume in the first second to the forced vital capacity (FEV1/FVC). The probability ranking results indicated that Liuzijue was the most effective, followed by Baduanjin, Wuqinxi, and Taichi. Subgroup analysis in conjunction with intervention duration revealed that Liuzijue had a significant advantage over other interventions for improving FEV1, FEV1%, and FEV1/FVC within 6 months and improved FEV1% and FEV1/FVC for ≥ 6 months. Moreover, Subgroup analysis based on baseline pulmonary function revealed that Liuzijue had a significant advantage over other interventions for improving FEV1% within severe and moderate groups. Finally, Subgroup analysis based on the frequency of interventions showed that Liuzijue was still more effective in improving FEV1, FEV1%, and FEV1/FVC in the ≥ three times one week.

CONCLUSION

Liuzijue was more effective than Taichi, Wuqinxi, Liuzijue, and Baduanjin in improving pulmonary function in patients with stable COPD.

Bronchial Progenitor Cells in Obstructive and Neoplastic Lung Disease: A Pilot Study

The alteration of progenitor/stem cells present in the airway epithelium has been observed in patients with COPD. Smoking exposure induces remodeling patterns in bronchial progenitor cells (BPCs), encompassing squamous metaplasia, hyperplasia of basal and of mucus-secreting cells, and the depletion of ciliated and non-mucous secretory cells. Our aim was to assess the expression of p63 and vimentin as potential markers of airway remodeling and the regulation of stem cell populations in obstructive and neoplastic lung disease patients. A retrospective single-center observational study was conducted, including patients undergoing bronchoscopy with bronchial biopsies for suspected lung cancer. p63 and vimentin expression were evaluated via immunohistochemical analysis. There were 25 patients, of which 21 with COPD were included, and 17 were diagnosed with lung cancer. We observed that FEV1% was negatively correlated with p63+ basal cell number (r = -0.614, p = 0.019) and positively correlated with vimentin expression (r = 0.670; p = 0.008). p63 was significantly higher in biopsies from the trachea and main bronchi compared to more distal areas (p = 0.040), whereas vimentin was prevalent in the more distal areas (p = 0.042). Our preliminary data suggest the initial evidence of structural changes in BPCs among patients with COPD and lung cancer. Further research efforts are warranted to investigate additional morphologic and functional respiratory parameters in these patients.

Lung Function Trajectories and Associated Mortality among Adults with and without Airway Obstruction

Rationale: Spirometry is essential for diagnosis and assessment of prognosis in patients with chronic obstructive pulmonary disease (COPD). Objectives: To identify FEV1 trajectories and their determinants on the basis of annual spirometry measurements among individuals with and without airway obstruction (AO) and to assess mortality in relation to trajectories. Methods: From 2002 through 2004, individuals with AO (FEV1/VC < 0.70, n = 993) and age- and sex-matched nonobstructive (NO) referents were recruited from population-based cohorts. Annual spirometry until 2014 was used in joint-survival latent-class mixed models to identify lung function trajectories. Mortality data were collected during 15 years of follow-up. Measurements and Main Results: Three trajectories were identified among the subjects with AO and two among the NO referents. Trajectory membership was driven by baseline FEV1% predicted (FEV1%pred) in both groups and also by pack-years in subjects with AO and current smoking in NO referents. Longitudinal FEV1%pred depended on baseline FEV1%pred, pack-years, and obesity. The trajectories were distributed as follows: among individuals with AO, 79.6% in AO trajectory 1 (FEV1 high with normal decline), 12.8% in AO trajectory 2 (FEV1 high with rapid decline), and 7.7% in AO trajectory 3 (FEV1 low with normal decline) (mean, 27, 72, and 26 ml/yr, respectively) and, among NO referents, 96.7% in NO trajectory 1 (FEV1 high with normal decline) and 3.3% in NO trajectory 2 (FEV1 high with rapid decline) (mean, 34 and 173 ml/yr, respectively). Hazard for death was increased for AO trajectories 2 (hazard ratio [HR], 1.56) and 3 (HR, 3.45) versus AO trajectory 1 and for NO trajectory 2 (HR, 2.99) versus NO trajectory 1. Conclusions: Three different FEV1 trajectories were identified among subjects with AO and two among NO referents, with different outcomes in terms of FEV1 decline and mortality. The FEV1 trajectories among subjects with AO and the relationship between low FVC and trajectory outcome are of particular clinical interest.

Mechanisms of lung damage in tuberculosis: implications for chronic obstructive pulmonary disease

Pulmonary tuberculosis is increasingly recognized as a risk factor for COPD. Severe lung function impairment has been reported in post-TB patients. Despite increasing evidence to support the association between TB and COPD, only a few studies describe the immunological basis of COPD among TB patients following successful treatment completion. In this review, we draw on well-elaborated Mycobacterium tuberculosis-induced immune mechanisms in the lungs to highlight shared mechanisms for COPD pathogenesis in the setting of tuberculosis disease. We further examine how such mechanisms could be exploited to guide COPD therapeutics.

PROMETHEUS: Long-Term Exacerbation and Mortality Benefits of Implementing Single-Inhaler Triple Therapy in the US COPD Population

Background: The US population includes 24 million to 29 million people with diagnosed and undiagnosed chronic obstructive pulmonary disease (COPD). Studies have demonstrated the safety and efficacy of single-inhaler triple therapy (SITT) in reducing COPD exacerbations. Long-term population implications of SITT use have not been quantified. Objectives: This simulation-based projection aimed to estimate the potential impact of widespread SITT use on the US COPD population. Methods: Exacerbation and all-cause mortality reductions reported in the Efficacy and Safety of Triple Therapy in Obstructive Lung Disease trial (ETHOS; NCT02465567) were used to project clinical outcomes in US patients meeting ETHOS trial eligibility criteria (ETHOS-Eligible) and patients meeting a practical definition of SITT eligibility (Expanded ETHOS-Eligible). The US COPD population was modeled with 1000 simulations of patient progression over 10 years. Agent characteristics were based on literature and claims analysis of the 2016-2018 Medicare 100% fee-for-service and IBM MarketScan® databases. Agent annual characteristics reflected incident cases, changes in COPD severity, treatment, mortality, and exacerbations under status quo treatment patterns and scenarios for the adoption of SITT. The scenarios assumed the reduced exacerbation and mortality rates associated with SITT according to ETHOS trial outcomes mean values. Results: Higher than current SITT adoption over 10 years would be expected to substantially reduce COPD exacerbation-associated hospitalizations by 2 million. Applying mean improvements reported in ETHOS for SITT would extend average patient life expectancy 2.2 years for ETHOS-Eligible patients and 1.7 years for Expanded ETHOS-Eligible patients. The number needed to treat to extend the average patient life by 1 year was 8 for the ETHOS-Eligible population and 10 for the Expanded ETHOS-Eligible population. Discussion: Widespread SITT adoption may be impeded by competitive pressures from generic treatments and nonadherence, and efficacy observed in clinical trials may not occur in real-world populations. Conclusions: Assuming ETHOS treatment effects and adherence translate to clinical practice, higher than current use of SITT can substantially reduce COPD exacerbations and hospitalizations and extend survival. These results should be viewed cautiously, because the improved outcomes for SITT in the ETHOS final retrieved vital statistics data were not statistically significant for all comparator therapy groups.

Functional Predictors Discriminating Asthma-COPD Overlap (ACO) from Chronic Obstructive Pulmonary Disease (COPD)

Background

A significant proportion of patients with obstructive lung disease have clinical and functional features of both asthma and chronic obstructive pulmonary disease (COPD), referred to as the asthma-COPD overlap (ACO). The distinction of these phenotypes, however, is not yet well-established due to the lack of defining clinical and/or functional criteria. The aim of our investigations was to assess the discriminating power of various lung function parameters on the assessment of ACO.

Methods

From databases of 4 pulmonary centers, a total of 540 patients (231 males, 309 females), including 372 patients with asthma, 77 patients with ACO and 91 patients with COPD, were retrospectively collected, and gradients among combinations of explanatory variables of spirometric (FEV1, FEV1/FVC, FEF25-75), plethysmographic (sReff, sGeff, the aerodynamic work of breathing at rest; sWOB), static lung volumes, including trapped gases and measurements of the carbon monoxide transfer (DLCO, KCO) were explored using multiple factor analysis (MFA). The discriminating power of lung function parameters with respect to ACO was assessed using linear discriminant analysis (LDA).

Results

LDA revealed that parameters of airway dynamics (sWOB, sReff, sGeff) combined with parameters of static lung volumes such as functional residual capacity (FRCpleth) and trapped gas at FRC (VTG FRC) are valuable and potentially important tools discriminating between asthma, ACO and COPD. Moreover, sWOB significantly contributes to the diagnosis of obstructive airway diseases, independent from the state of pulmonary hyperinflation, whilst the diffusion capacity for carbon monoxide (DLCO) significantly differentiates between the 3 diagnostic classes.

Conclusion

The complexity of COPD with its components of interaction and their heterogeneity, especially in discrimination from ACO, may well be differentiated if patients are explored by a whole set of target parameters evaluating, interactionally, flow limitation, airway dynamics, pulmonary hyperinflation, small airways dysfunction and gas exchange disturbances assessing specific functional deficits.

Small Airway Dysfunction in Chronic Bronchitis with Preserved Pulmonary Function

Impairment of pulmonary function was evaluated in chronic bronchitis patients with preserved ratio impaired spirometry (PRISm). We retrospectively collected clinical data from 157 chronic bronchitis (CB) and 186 chronic obstructive pulmonary disease (COPD) patients between October 2014 and September 2017. These patients were assigned to three groups: control (normal pulmonary function), PRISm (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC] ≥ 0.7, FEV1 < 80% of predicted value), and COPD (FEV1/FVC <0.7) groups. Because small airway function was the main focus, in the COPD group, only patients in accordance with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) grades 1 and 2 were included. Evaluation of pulmonary function (including impulse oscillometry) was performed and compared among these groups. Compared with the control group, the PRISm and COPD groups showed statistically significant differences in the predicted FEV1% $\left(p<0.001\right)$ , maximal expiratory flow (MEF) 25% $\left(p<0.001\right)$ , MEF50% $\left(p<0.001\right)$ , maximal midexpiratory flow (MMEF) 25–75% $\left(p<0.001\right)$ , residual volume (RV)/total lung capacity (TLC; $p<0.001$ ), FVC% $\left(p<0.001\right)$ , total respiratory resistance and proximal respiratory resistance (R5-R20; $p<0.001$ ), respiratory system reactance at 5 Hz (X5; $p<0.001$ ), resonant frequency (Fres; $p<0.001$ ), and area of reactance (Ax; $p<0.001$ ). However, the predicted FEV1% and RV/TLC were similar between the PRISm and COPD groups ( $p=0.992$ and 0.122, respectively). PRISm is a nonspecific pattern of pulmonary function that indicates small airway dysfunction and may increase the risk of transformation to obstructive ventilation dysfunction. This trial is registered with ChiCTR-OCH-14004904.

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.

Complexity of design in early phase respiratory clinical trials; evaluating impact of primary endpoints and sponsor size

Asthma and COPD represent most of the clinical trials in the respiratory area. The Primary Endpoint (PE) defines how trials are conducted. We hypothesised that small and mid-sized pharmaceutical companies may be innovative in the selection of their trial endpoints, to be time- and cost-effective. To test this, a record of industry-sponsored phase II trials in asthma, COPD and Asthma/COPD over 11 years was obtained. The type of PE and the influence these had on length, number of subjects and investigational trial sites were evaluated for the different disease categories. Differences in the type of PE used by large versus small/mid-sized companies were found for both asthma and COPD trials (p = 0.011 and 0.025), with sponsorship influencing the conduction of these. In asthma, studies sponsored by large companies were significantly longer than those from smaller companies (p = 0.0001). Additionally, large companies intended to recruit more subjects (asthma: p = 0.0048, COPD: p ≤ 0.0001) and use more investigational sites (asthma: p = 1 × 10-7, COPD: p = 1 × 10-5) than those from small and mid-size companies. A sub-analysis of the time and subject requirements associated with each type of PE did not provide an explanation for the differences observed. In conclusion, this exploratory analysis indicates differences in study size, duration and type of PE used by small/mid-sized and large companies. For some types of endpoints, differences in length and study size were found. However, it wasn't possible to attribute these differences between sponsors solely to the choice of PE, pointing out to the complexity of running clinical trials.

Association between insulin resistance and lung function trajectory over 4 years in South Korea: community-based prospective cohort

Background

Hyperglycemic conditions are associated with respiratory dysfunction. Although several studies have reported that insulin resistance (IR) is related to decreased lung function, the association between IR and change in lung function has been rarely studied. This study aimed to investigate the potential association of IR on annual change in lung function using a community-based prospective cohort in Korea.

Methods

We selected 4827 Korean participants whose serial lung functions were assessed over 4 years using 1:3 propensity score matching. Exposure was baseline IR estimated with homeostatic model assessment (HOMA-IR), and outcomes were annual changes in lung function determined by calculating the regression coefficient using least-square linear regression analysis.

Results

In the multivariate linear regression, per one unit increased log transformed HOMA-IR was associated with decline in FEV₁%-predicted (β: − 0.23, 95% CI: − 0.36 to − 0.11) and FVC %-predicted (β: − 0.20, 95% CI: − 0.33 to − 0.08), respectively. In the generalized additive model plot, HOMA-IR showed a negative linear association with annual changes in FEV₁%-predicted and FVC %-predicted. The suggested threshold of HOMA-IR for decline in lung function was 1.0 unit for annual change in FEV₁%-predicted and 2.2 unit for annual change in FVC %-predicted. Age showed statistically significant effect modification on the relationship between HOMA-IR and annual change in FEV₁%-predicted. Increased HOMA-IR was associated with the decreased annual change in FEV₁%-predicted, particularly in older people.

Conclusions

In South Korea, increased HOMA-IR was associated with decline in lung function. Since IR was related to decline in FEV₁%-predicted, particularly in older people, tailored approaches are needed in these populations. The potential pulmonary hazard of IR needs to be confirmed in future studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01478-7.

Natural history and mechanisms of COPD

The natural history of COPD is complex, and the disease is best understood as a syndrome resulting from numerous interacting factors throughout the life cycle with smoking being the strongest inciting feature. Unfortunately, diagnosis is often delayed with several longitudinal cohort studies shedding light on the long 'preclinical' period of COPD. It is now accepted that individuals presenting with different COPD phenotypes may experience varying natural history of their disease. This includes its inception, early stages and progression to established disease. Several scenarios regarding lung function course are possible, but it may conceptually be helpful to distinguish between individuals with normal maximally attained lung function in their early adulthood who thereafter experience faster than normal FEV₁ decline, and those who may achieve a lower than normal maximally attained lung function. This may be the main mechanism behind COPD in the latter group, as the decline in FEV₁ during their adult life may be normal or only slightly faster than normal. Regardless of the FEV₁ trajectory, continuous smoking is strongly associated with disease progression, development of structural lung disease and poor prognosis. In developing countries, factors such as exposure to biomass and sequelae after tuberculosis may lead to a more airway-centred COPD phenotype than seen in smokers. Mechanistically, COPD is characterized by a combination of structural and inflammatory changes. It is unlikely that all patients share the same individual or combined mechanisms given the heterogeneity of resultant phenotypes. Lung explants, bronchial biopsies and other tissue studies have revealed important features. At the small airway level, progression of COPD is clinically imperceptible, and the pathological course of the disease is poorly described. Asthmatic features can further add confusion. However, the small airway epithelium is likely to represent a key focus of the disease, combining impaired subepithelial crosstalk and structural/inflammatory changes. Insufficient resolution of inflammatory processes may facilitate these changes. Pathologically, epithelial metaplasia, inversion of the goblet to ciliated cell ratio, enlargement of the submucosal glands and neutrophil and CD8-T-cell infiltration can be detected. Evidence of type 2 inflammation is gaining interest in the light of new therapeutic agents. Alarmin biology is a promising area that may permit control of inflammation and partial reversal of structural changes in COPD. Here, we review the latest work describing the development and progression of COPD with a focus on lung function trajectories, exacerbations and survival. We also review mechanisms focusing on epithelial changes associated with COPD and lack of resolution characterizing the underlying inflammatory processes.

Dual– Versus Mono–Bronchodilator Therapy in Moderate to Severe COPD: A Meta-analysis

Background:

Chronic obstructive pulmonary disease (COPD) guidelines recommend both long-acting and dual bronchodilator therapy. It is unclear if there are differences in efficacy and safety.

Objective:

This meta-analysis evaluates the efficacy of dual therapy with long-acting β-agonist (LABA) + long acting muscarinic antagonist (LAMA) compared with monotherapy with LAMA for COPD.

Methods:

We searched PubMed, CINAHL, and Web of Science databases from inception through March 2020 to identify English-language, prospective randomized controlled trials (RCTs) that compared dual therapy with monotherapy in adult patients with COPD. Risk of bias was assessed using the Jadad score. Overall analysis was performed using Review Manager 5.3. Treatment effect was determined with the random-effects model using the Mantel-Haenszel method and was reported as mean difference (MD) with 95% CI.

Results:

A total of 18 RCTs were included (n = 6086; median Jadad score 5/5) that compared LAMA + LABA with LAMA. There was a greater improvement in forced expiratory volume at 1 s (FEV1) with dual therapy compared with LAMA: MD = 0.08; 95% CI = [0.05, 0.11]. There was no difference in St George Respiratory Questionnaire (SGRQ) scores between groups: OR = −0.85; 95% CI = [−1.83, 0.13]. There were no differences in overall adverse events (OR = 1.00; 95% CI = 0.92, 1.09), serious adverse events (OR = 1.01; 95% CI = 0.86, 1.18), or cardiovascular events (OR = 0.88; 95% CI = 0.58, 1.34).

Conclusion and Relevance:

Dual therapy improves FEV1 and is as safe as LAMA. Dual therapy does not improve SGRQ scores more than LAMA.

Contributions of burning incense on indoor air pollution levels and on the health status of patients with chronic obstructive pulmonary disease

Background

Among Buddhist or Taoist Taiwanese residents, burning incense is a common source of indoor particulate matter (PM), including PM₁₀ and PM_2.5, and can adversely affect the health status of patients with chronic obstructive pulmonary diseases (COPD). However, few studies have focused on the effects of intermittent burning of incense on PM concentration levels and the health status of patients with COPD. This correlational cohort study aimed to investigate the association between burning incense exposure duration, indoor air pollution levels, and lung function in patients with COPD in Taiwan.

Methods

We assessed 18 outpatients at seven time points with moderate-to-severe COPD using the COPD Assessment Test (CAT), and lung function tests. PM level changes were assessed at seven intervals using generalized estimating equations.

Results

Participants were primarily male (84%), with a mean age of 72.1 (standard deviation (SD)  ± 9.3) years, and with a mean COPD duration of 3.7 (SD  ± 3.1) years. Both PM₁₀ and PM_2.5 levels were the same as the background levels 1 h after incense burning. Burning incense may not influence lung function or symptom severity in patients with COPD in a short-time period. Air quality returned to baseline levels 1 h after burning incense.

Conclusion

Patients with COPD should avoid staying in rooms where incense is burnt, for up to 1 h. The small sample size and short study period may have influenced our results. Future longitudinal studies with larger sample sizes and long-term follow-ups are recommended.

Statin use and lung cancer risk in chronic obstructive pulmonary disease patients: a population-based cohort study

Background

Patients living with chronic obstructive pulmonary disease (COPD) are at an increased risk of lung cancer. A common comorbidity of COPD is cardiovascular disease; as such, COPD patients often receive statins. This study sought to understand the association between statin exposure and lung cancer risk in a population-based cohort of COPD patients.

Methods

We identified a population-based cohort of COPD patients based on having filled at least three prescriptions for an anticholinergic or short-acting beta-agonist (SABA). We used an array of methods of defining medication exposure including three conventional methods (ever statin exposure, cumulative duration of use, and cumulative dose) and two novel methods (recency-weighted cumulative duration of use and recency-weighted cumulative dose). To assess residual confounding, a negative control exposure was used to test the validity of our results. All exposure variables were time-dependent.

Results

The population-based cohort of COPD had 39,879 patients with mean age of 70.6 (SD: 11.2) years and, of which, 53.5% were female. There were 12,469 patients who received at least one statin prescription. Results from the reference case multivariable analysis indicated a reduced risk from statin exposure (HR: 0.85 (95% CI: 0.73–1.00) in COPD patients, but this result not statistically significant. Using the two recency-weighted modelling approaches, statin exposure was associated with a statistically significant reduction in lung cancer risk (recency-weighted cumulative dose, HR: 0.85 (95% CI: 0.77–0.93) and recency-weighted cumulative duration of use, HR: 0.97 (95% CI: 0.96–0.99). Multivariable analysis incorporating the negative control exposure was not statistically significant (HR: 0.89 (95% CI: 0.75–1.10).

Conclusions

The results of this population-based analysis indicate that statin use in COPD patients may reduce the risk of lung cancer. While the effect was not statistically significantly across all exposure definitions, the overall results support the hypothesis that COPD patients might benefit from statin therapy.

Frequent Outpatient Visits Prevent Exacerbation of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory airway disease requiring frequent outpatient visits and lifelong management. We aimed to evaluate the roles of frequent outpatient visits in prognosis of COPD. We used claims data in the national medical insurance review system provided by the Health Insurance Review and Assessment Service of Korea from May 1, 2014 to April 30, 2015. A definition of COPD was used based on the diagnosis code and medication. Frequent visitors were defined as subjects who visited the outpatient clinic for COPD three or more times per year. Among 159,025 subjects, 117,483 (73.9%) were classified as frequent visitors. Frequent visitors underwent pulmonary function tests and used various inhalers more often than did infrequent visitors. The rates of COPD exacerbation requiring admission to a general ward, emergency room, or intensive care unit were significantly lower in frequent visitors than in infrequent visitors. In multivariable analysis, frequent visits were identified as an independent factor preventing COPD exacerbation that required admission to a ward (odds ratio [OR], 0.387), emergency room, (OR, 0.558), or intensive care unit (OR, 0.39) (all P < 0.001). In conclusion, we showed frequent outpatient visits reduce the risk of COPD exacerbation by 45-60%.

Weighing the evidence for pharmacological treatment interventions in mild COPD; a narrative perspective

There is increasing focus on understanding the nature of chronic obstructive pulmonary disease (COPD) during the earlier stages. Mild COPD (Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage 1 or the now-withdrawn GOLD stage 0) represents an early stage of COPD that may progress to more severe disease. This review summarises the disease burden of patients with mild COPD and discusses the evidence for treatment intervention in this subgroup.

Overall, patients with mild COPD suffer a substantial disease burden that includes persistent or potentially debilitating symptoms, increased risk of exacerbations, increased healthcare utilisation, reduced exercise tolerance and physical activity, and a higher rate of lung function decline versus controls. However, the evidence for treatment efficacy in these patients is limited due to their frequent exclusion from clinical trials. Careful assessment of disease burden and the rate of disease progression in individual patients, rather than a reliance on spirometry data, may identify patients who could benefit from earlier treatment intervention.

Lung function trajectories and chronic obstructive pulmonary disease: current understanding and knowledge gaps

PURPOSE OR REVIEW

Population-based studies have shown a significant heterogeneity in patients with chronic obstructive pulmonary disease (COPD), regarding both the attainment of maximal lung function and the subsequent decline over time. This review will highlight recent advances in the understanding of lung function trajectory in COPD, focusing on factors that influence peak adult lung function, markers of accelerated lung function decline and pharmacologic interventions in early phases of the disease.

RECENT FINDINGS

Recent data have shown that individuals with lower lung function early in life will go on to develop lower forced expiratory volume in 1 s (FEV1) in adulthood. Smoking can amplify the effect of specific childhood exposures on maximal adult lung function. Clinical symptoms such as chronic mucous hypersecretion and the biomarker club cell secretory protein have been associated with lung function decline over time. New computed tomography imaging markers also show promise as a way to detect early small airway disease, but need to be examined more longitudinally. In addition to these advances, a slower decline in FEV1 has been demonstrated in two randomized clinical trials studying tiotropium and inhaled fluticasone.

SUMMARY

A better understanding of lung function development and eventual decline in those at risk for progression to COPD will aide in a precision medicine approach, in which markers for those at risk of low maximal lung function and accelerated decline are identified. Targeted therapy can then be used early to modify disease activity and outcomes.

Declining Lung Function and Cardiovascular Risk: The ARIC Study

BACKGROUND

Pulmonary dysfunction predicts incident cardiovascular disease (CVD).

OBJECTIVES

The purpose of this study was to evaluate whether longitudinal decline in lung function is associated with incident heart failure (HF), coronary heart disease (CHD), and stroke.

METHODS

Among 10,351 participants in the ARIC (Atherosclerosis Risk In Communities) study free of CVD, rapid lung function decline was defined as the greatest quartile (n = 2,585) of decline in either forced expiratory volume in 1 s (FEV1) (>1.9% decline/year) or forced vital capacity (FVC) (>2.1% decline/year) over 2.9 ± 0.2 years. The relationship between rapid decline in FEV1 or FVC and subsequent incident HF, CHD, stroke, or a composite of these was assessed using multivariable Cox regression adjusting for the baseline spirometry value, demographics, height, body mass index, heart rate, diabetes, hypertension, low-density lipoprotein, use of lipid-lowering medication, N-terminal fragment of prohormone for B-type natriuretic peptide, and smoking.

RESULTS

The mean age was 54 ± 6 years, 56% were women, and 81% were white. At 17 ± 6 years of follow-up, HF occurred in 14%, CHD 11%, stroke 6%, and the composite in 24%. Rapid decline in FEV1 and in FVC were both associated with a heightened risk of incident HF (hazard ratio [HR]: 1.17; 95% confidence interval [CI]: 1.04 to 1.33; p = 0.010; and HR: 1.27; 95% CI: 1.12 to 1.44; p < 0.001; respectively), with rapid decline in FEV1 most prognostic in the first year of follow-up (HR: 4.22; 95% CI: 1.34 to 13.26; p = 0.01). Rapid decline in FEV1 was also associated with incident stroke (HR: 1.25; 95% CI: 1.04 to 1.50; p = 0.015).

CONCLUSIONS

A rapid decline in lung function, assessed by serial spirometry, is associated with a higher incidence of subsequent CVD, particularly incident HF.

EARLY versus MILD Chronic Obstructive Pulmonary Disease (COPD)

Chronic Obstructive Pulmonary Disease (COPD) is very a common, with great morbidity and mortality, disease. Since the beginning of the disease cannot be detected with precision and by using only FEV1 to monitor the evolution of the disease, the Natural History of COPD is rather obscure and sometimes controversial. Therefore, the terms EARLY COPD and MILD COPD have been used indistinguishably in the medical literature. In this review we discuss the two terms trying to clarify some of the definition issues, starting with a synopsis of the Naturel History of the disease. We recommend to use the term EARLY COPD for the pre-clinical stage of the disease (stage 0) and the term MILD COPD when the diagnosis is confirmed by spirometry and FEV1 is above 80% predicted. However, COPD is a complex disease and spirometric evaluation alone (MILD COPD, stage I), cannot fully describe the clinical status of the patient. We conclude that biomarkers to detect the starting point and been able to follow the natural history of the disease more accurately, beyond FEV, are urgently needed.

Proteolytic biomarkers are related to prognosis in COPD- report from a population-based cohort

BACKGROUND

The imbalance between proteases and anti-proteases is considered to contribute to the development of COPD. Our aim was to evaluate the protease MMP-9, the antiprotease TIMP-1 and the MMP-9/TIMP-1-ratio as biomarkers in relation to prognosis. Prognosis was assessed as lung function decline and mortality. This was done among subjects with COPD in a population-based cohort.

METHODS

In 2005, clinical examinations including spirometry and peripheral blood sampling, were made in a longitudinal population-based cohort. In total, 1542 individuals participated, whereof 594 with COPD. In 2010, 1031 subjects participated in clinical examinations, and 952 subjects underwent spirometry in both 2005 and 2010. Serum MMP-9 and TIMP-1 concentrations were measured with enzyme linked immunosorbent assay (ELISA). Mortality data were collected from the Swedish national mortality register from the date of examination in 2005 until 31st December 2010.

RESULTS

The correlation between biomarkers and lung function decline was similar in non-COPD and COPD, but only significant for MMP-9 and MMP-9/TIMP-1-ratio in non-COPD. Mortality was higher in COPD than non-COPD (16% vs. 10%, p = 0.008). MMP-9 concentrations and MMP-9/TIMP-1 ratios in 2005 were higher among those who died during follow up, as well as among those alive but not participating in 2010, when compared to those participating in the 2010-examination. In non-COPD, male sex, age, burden of smoking, heart disease and MMP-9/TIMP-1 ratio were associated with increased risk for death, while increased TIMP-1 was protective. Among those with COPD, age, current smoking, increased MMP-9 and MMP-9/TIMP-1 ratio were associated with an increased risk for death.

CONCLUSIONS

The expected association between these biomarkers and lung function decline in COPD was not confirmed in this population-based study, probably due to a healthy survivor effect. Still, it is suggested that increased proteolytic imbalance may be of greater prognostic importance in COPD than in non-COPD.

Dokumentiranje navodil o življenjskem slogu in samoobvladovanju bolezni pri pacientih s kronično obstruktivno pljučno boleznijo

Uvod: Za boljše doseganje kakovosti življenja pacientov s kronično obstruktivno pljučno boleznijo je slednje treba poučiti o značilnostih bolezni ter o ukrepih za njeno učinkovito samoobvladovanje. Namen raziskave je bil ugotoviti pogostost dokumentiranja in vrsto dokumentiranih navodil o življenjskem slogu in samoobvladovanju bolezni v bolnišnični dokumentaciji pacientov s kronično obstruktivno pljučno boleznijo.Metode: Izvedena je bila retrospektivna kvantitativna raziskava, v kateri je bila pregledana celotna bolnišnična dokumentacija (terapevtski listi, liste zdravstvene nege, arhivi zdravstvenovzgojnih šol, odpustna pisma) 253 pacientov s kronično obstruktivno pljučno boleznijo. Za analizo podatkov sta bila poleg osnovne deskriptivne statistike uporabljena tudi hi-kvadrat test in ordinalna logistična regresija.Rezultati: V bolnišnični dokumentaciji so pacienti s kronično obstruktivno pljučno boleznijo imeli dokumentirana v povprečju manj kot 4 navodila o življenjskem slogu in samoobvladovanju bolezni (x = 3,8, s = 5,1). V odpustnem pismu je polovica pacientov (x = 0,5, s = 0,9) imela zabeleženih manj navodil o življenjskem slogu in samoobvladovanju bolezni kot v bolnišnični dokumentaciji (x2 = 33,455, p < 0,001). Diplomirane medicinske sestre so navodila dokumentirale petkrat pogosteje kot zdravniki.Diskusija in zaključek: Raziskava je za bolnišnično dokumentacijo pacientov s kronično obstruktivno pljučno boleznijo ugotovila nizko število dokumentiranih navodil o življenjskem slogu in samoobvladovanju bolezni. Treba bo povečati ozaveščenost o pomenu dokumentiranja zdravstvenovzgojnih navodil in oblikovati orodja za izboljšanje medpoklicne komunikacije.

From COPD epidemiology to studies of pathophysiological disease mechanisms: challenges with regard to study design and recruitment process: Respiratory and Cardiovascular Effects in COPD (KOLIN)

Background: Chronic obstructive pulmonary disease (COPD) is a largely underdiagnosed disease including several phenotypes. In this report, the design of a study intending to evaluate the pathophysiological mechanism in COPD in relation to the specific phenotypes non-rapid and rapid decline in lung function is described together with the recruitment process of the study population derived from a population based study. Method: The OLIN COPD study includes a population-based COPD cohort and referents without COPD identified in 2002-04 (n = 1986), and thereafter followed annually since 2005. Lung function decline was estimated from baseline in 2002-2004 to 2010 (first recruitment phase) or to 2012/2013 (second recruitment phase). Individuals who met the predefined criteria for the following four groups were identified; group A) COPD grade 2-3 with rapid decline in FEV₁ and group B) COPD grade 2-3 without rapid decline in FEV₁ (≥60 and ≤30 ml/year, respectively), group C) ever-smokers, and group D) non-smokers with normal lung function. Groups A-C included ever-smokers with >10 pack years. The intention was to recruit 15 subjects in each of the groups A-D. Results: From the database groups A-D were identified; group A n = 37, group B n = 29, group C n = 41, and group D n = 55. Fifteen subjects were recruited from groups C and D, while this goal was not reached in the groups A (n = 12) and B (n = 10). The most common reasons for excluding individuals identified as A or B were comorbidities contraindicating bronchoscopy, or inflammatory diseases/immune suppressive medication expected to affect the outcome. Conclusion: The study is expected to generate important results regarding pathophysiological mechanisms associated with rate of decline in lung function among subjects with COPD and the in-detail described recruitment process, including reasons for non-participation, is a strength when interpreting the results in forthcoming studies.

Measurement of cardiovascular and pulmonary function endpoints and other physiological effects following partial or complete substitution of cigarettes with electronic cigarettes in adult smokers

Acute changes in select physiological parameters associated with cardiovascular physiology (systolic and diastolic blood pressure (BP) and heart rate (HR)), pulmonary function (FVC, FEV1, and exhaled CO and NO) and adverse events were measured in 105 clinically confined subjects who were randomized into groups that either completely or partially switched from conventional cigarettes to e-cigarettes or completely discontinued using tobacco and nicotine products altogether. Use of the e-cigarettes for five days under the various study conditions did not lead to higher BP or HR values, negative respiratory health outcomes or serious adverse health events. Reductions in BP and HR vital signs were observed in most of the participants that either ceased tobacco and nicotine products use altogether or switched completely to using e-cigarettes. Pulmonary function tests showed small but non-statistically significant improvements in FVC and FEV1 measurements in most use groups. Statistically significant (p < 0.05) benefits associated with smoking reduction were also noted in exhaled CO and NO levels. All study products were well tolerated. The study findings suggest that there are potential cardiovascular and pulmonary function benefits when smokers switch to using e-cigarette products. This further reinforces the potential that e-cigarettes offer smokers seeking an alternative to conventional tobacco products.

Efficacy of tiotropium-olodaterol fixed-dose combination in COPD

Tiotropium-olodaterol, formulated in the Respimat soft-mist inhaler, is an inhaled fixed-dose combination (FDC) of a long-acting muscarinic antagonist (LAMA) and a long-acting β2-agonist (LABA), commercialized under the name of Spiolto or Stiolto. The efficacy of tiotropium-olodaterol 5-5 μg once daily in adult patients with COPD was documented in eleven large, multicenter trials of up to 52 weeks duration. Tiotropium-olodaterol 5-5 μg not only improved spirometric values to a significantly greater extent than placebo but also resulted in statistically significant beneficial effects on dyspnea, markers of hyperinflation, use of rescue medication, health-related quality of life, and exercise endurance. Improvements exceeded the minimal clinically important difference (MCID) for forced expiratory volume in 1 second (FEV1), dyspnea, and quality of life. Differences between tiotropium-olodaterol 5-5 μg and the respective monocomponents were statistically significant for FEV1, dyspnea, markers of hyperinflation, use of rescue medication, and health-related quality of life, but did not reach the MCID. However, dual bronchodilatation significantly increased the number of patients who exceeded the MCID for dyspnea and quality of life. Moreover, tiotropium-olodaterol 5-5 μg was significantly more effective than salmeterol-fluticasone (FDC) twice daily at improving pulmonary function. Differences between tiotropium-olodaterol and other LAMA/LABA FDCs were not observed for FEV1 or other efficacy markers. Therefore, tiotropium-olodaterol is a valuable option in the treatment of COPD patients who remain symptomatic under monotherapy.

Do inhaled corticosteroids protect against lung cancer in patients with COPD? A systematic review

Inhaled corticosteroids (ICS) are commonly prescribed to COPD patients, particularly those with more advanced stages of the disease. These patients are also at increased risk of lung cancer. A systematic review was undertaken to identify studies that examined the association between lung cancer risk and ICS therapy in COPD patients. The search strategy was created in MEDLINE and extended to EMBASE as well as other relevant databases. Both randomized controlled trials (RCTs) and observational studies were considered for inclusion. Studies were required to have incident lung cancer or deaths from lung cancer as an outcome in order to be included in the review. Six studies met the inclusion criteria. Two observational studies directly addressed the specific research. Four RCTs presented sufficient data to calculate the relative risk of lung cancer in COPD patients. None of the identified RCTs showed a statistically significant association of ICS use with lung cancer risk. Observational studies showed a protective effect from ICS use, particularly at high doses. Given the observational evidence and the low numbers of lung cancer events in the RCTs, these results may be prone to type II error. The observational studies dealt with very specific patient populations and exposure definitions, which might not have adequately captured the complex relationship between ICS exposure and lung cancer risk. Results from RCTs suggest no effect of ICS on the risk of lung cancer. However, results from observational studies suggest the potential that ICS may confer a protective effect, particularly at high doses.

Evaluation of Individuals at Risk for COPD: Beyond the Scope of the Global Initiative for Chronic Obstructive Lung Disease

The Global initiative for chronic Obstructive Lung Disease (GOLD) Strategy is a valuable tool for clinicians in the diagnosis and management of patients with established chronic obstructive pulmonary disease (COPD). However, there are no recommendations for the evaluation of individuals, exposed to risk factors, who are most likely to develop COPD. Consequently, it is necessary to consider all of the factors that may play a role in the pathogenesis of COPD: genetic factors, gender, socioeconomic status, disadvantageous factors in childhood, lung diseases and exposure to risk factors such as smoking, biomass fuel smoke, occupational hazards and air pollution. Along with the clinical assessment, periodic spirometry should be performed to evaluate lung function and make possible early detection of individuals who will develop the disease through the rate of forced expiratory volume in 1 second (FEV₁) decline. The first spirometry, periodicity, and clinically significant decline in FEV₁ will encompass the cornerstones of clinical follow up. This approach allows the implementation of important interventions in order to help individuals to cease contact with risk factors and prevent progressive respiratory impairment with the consequent deterioration of quality of life and increased morbidity and mortality.