Clinical Significance of Symptoms in Smokers with Preserved Pulmonary Function

Association of mild chronic obstructive pulmonary disease with all-cause mortality: A systematic review and meta-analysis

BACKGROUND

It is unclear whether patients with Global Initiative for Chronic Obstructive Lung Disease stage 1 (mild) chronic obstructive pulmonary disease (COPD) have worse respiratory outcomes than individuals with normal spirometry.

METHODS

For this systematic review and meta-analysis, we conducted a search of PubMed, Embase, and Web of Science for all literature published up to 1 March 2023. Studies comparing mortality between mild COPD and normal spirometry were included. A random-effects model was used to estimate the combined effect size and its 95% confidence interval (CI). The primary outcome was all-cause mortality. Respiratory disease-related mortality were examined as secondary outcomes.

RESULTS

Of 5242 titles identified, 12 publications were included. Patients with mild COPD had a higher risk of all-cause mortality than individuals with normal spirometry (pre-bronchodilator: hazard ratio [HR] = 1.21, 95% CI: 1.11-1.32, I2 = 47.1%; post-bronchodilator: HR = 1.19, 95% CI: 1.02-1.39, I2 = 0.0%). Funnel plots showed a symmetrical distribution of studies and did not suggest publication bias. In jackknife sensitivity analyses, the increased risk of all-cause mortality remained consistent for mild COPD. When the meta-analysis was repeated and one study was omitted each time, the HR and corresponding 95% CI were >1. Patients with mild COPD also had a higher risk of respiratory disease-related mortality (HR = 1.71, 95% CI: 1.03-2.82, I2 = 0.0%).

CONCLUSIONS

Our results suggest that mild COPD is associated with increased all-cause mortality and respiratory disease-related mortality compared with normal spirometry. Further research is required to determine whether early intervention and treatment are beneficial in mild COPD.

Respiratory symptoms in preserved ratio impaired spirometry: Link to comorbidities and increased mortality risk

BACKGROUNDX

Respiratory symptoms are frequently observed in subjects with Preserved Ratio Impaired Spirometry (PRISm); however, their association with comorbidities and mortality in this population remains poorly understood.

METHODS

Data from the National Health and Nutrition Examination Survey (2007-2012) were analyzed. Logistic regression was used to assess the association between respiratory symptoms and comorbidities, while Cox regression was applied to evaluate mortality risks.

RESULTS

This study included 5612 adults aged 40 years and older with normal spirometry and 754 participants with PRISm. Among the PRISm group, 331 subjects (43.8 %) reported one or more respiratory symptoms. Compared to individuals with normal spirometry, PRISm subjects with respiratory symptoms exhibited a significantly higher prevalence of comorbidities, including hypertension, diabetes, angina, myocardial infarction, heart failure, and stroke, as well as increased risks of all-cause and cardiovascular mortality. In contrast, PRISm without respiratory symptoms was primarily associated with diabetes and an elevated mortality risk. When comparing PRISm subjects with and without respiratory symptoms, those with symptoms had a markedly higher prevalence of hypertension (OR 1.10, 95 % CI: 1.08-1.11), myocardial infarction (OR 5.75, 95 % CI: 2.25-14.67), heart failure (OR 5.52, 95 % CI: 2.50-12.19), and cancer (OR 2.34, 95 % CI: 1.12-4.86). Additionally, PRISm subjects with respiratory symptoms faced a significantly elevated risk of cardiovascular mortality (HR 1.55, 95 % CI: 1.38-1.74).

CONCLUSIONS

Respiratory symptoms were associated with a significantly higher burden of comorbidities and an increased risk of cardiovascular mortality in PRISm subjects.

Vitamin D Supplementation, Chronic Obstructive Lung Disease and Asthma Exacerbations, and Lung Function Decline

BACKGROUND

It remains unclear whether supplementation with vitamin D reduces risk of acute exacerbations of chronic obstructive lung disease (COPD) or asthma, major contributors to the world-wide burden of disease.

OBJECTIVES

To compare effects of vitamin D with placebo supplementation for the prespecified primary endpoints 1) acute exacerbations of COPD and 2) decline in pulmonary function measures of airflow obstruction. Prespecified secondary endpoints included asthma exacerbations and control.

METHODS

Lung VITamin D and OmegA-3 TriaL (VITAL) is an ancillary study of VITAL, a United States nationwide, randomized, placebo-controlled trial with a 2-by-2 factorial design of vitamin D3 (2000 IU/d) and marine n-3 fatty acids (1 g/d) among men 50 y and women 55 y of age or older. Of 25,871 randomly divided participants, 3632 at risk for respiratory exacerbations, including 1977 with COPD by diagnosis or symptoms and 1654 with self-reported asthma diagnosis, were followed annually for 5 y by self-administered respiratory questionnaire. Spirometry was performed at baseline and 2 y after randomization by 1648 participants from 12 urban centers. Decline in forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity was measured between baseline and follow-up.

RESULTS

Supplementation with vitamin D was not associated with lower risk of any primary or secondary end point. Over the 5-y follow-up, the number of COPD exacerbations was 0.27/y in the vitamin D group and 0.25/y in the placebo group (rate ratio 1.10; 95% confidence interval, 0.93, 1.29). Over the 2-y follow-up, supplementation was not associated with slower decline (mL/y) in FEV1.

CONCLUSIONS

Supplementation with vitamin D, compared with placebo, did not result in a lower rate of COPD exacerbations or improved pulmonary function in community-dwelling adults not selected for vitamin D deficiency. This trial was registered at Lung VITAL clinicaltrials.gov as NCT01728571 with Protocol ID 2010-P-000622 (https://prevention.cancer.gov/clinical-trials/clinical-trials-search/nct01728571).

Assessing the Italian version of the respiratory symptom experience scale (IT-RSES) in smokers and former smokers: a validation study

BACKGROUND

Smoking causes respiratory symptoms, and research suggests these improve with cessation or switching to less harmful nicotine products. The Respiratory Symptom Experience Scale (RSES) was developed and validated for the purpose of assessing these such symptoms online in an English-speaking American sample. This study aimed to develop and validate an Italian version, the IT-RSES, administered via telephone interview, and, further, to use it to assess symptoms in smokers who had switched to e-cigarettes or to heated tobacco products (HTPs).

METHODS

After translation into Italian, the IT-RSES was administered by phone interview to 750 Italian participants in 5 tobacco use groups (150 each never-smokers, former smokers not using alternative products, HTP users, e-cigarette users, and continuing smokers) who also reported any history of diagnoses with relevant medical conditions. Psychometric analyses examined scale factor structure, reliability, and convergent validity. Analyses controlling for age and for years smoking compared symptoms across tobacco use groups.

RESULTS

Factor analyses confirmed the IT-RSES' unidimensionality (factor one accounting for 74.2% of the variance; all factor loadings > 0.80). Internal-consistency reliability was high ( Cronbach's alpha = 0.91). IT-RSES scores correlated significantly with years of smoking (r = 0.51, p < 0.0001), and were higher in individuals with respiratory conditions (2.02 vs. 1.36, SE = 0.05, significant by THSD). Discriminant validity was demonstrated by higher scores in smokers compared to never-smokers, even among those without respiratory conditions. After adjustment for years of smoking, former smokers, HTP users and e-cigarette users had lower scores than smokers (m = 2.17 vs. 1.49, SE = 0.06, p < 0.05, THSD; 1.63 vs. 2.16, SE = 0.06, THSD) and did not significantly differ from each other.

CONCLUSIONS

The results support the reliability and validity of the IT-RSES, suggesting its utility for assessing respiratory symptoms in smokers, and former smoker who stopped smoking and were using e-cigarettes or HTPs. The scores of former smokers are similar to those not using these products, and lower than smokers', suggests that HTPs and e-cigarettes do not add materially to respiratory symptoms when smokers stop smoking.

Traditional Chinese Exercise Improves Lung Function and Exercise Capacity in Patients with Preserved Ratio Impaired Spirometry

OBJECTIVE

To investigate the effect of traditional Chinese Five-body balance exercise on patients with preserved ratio impaired spirometry (PRISm).

METHODS

Fifteen patients with PRISm and 15 patients diagnosed with chronic obstructive pulmonary disease (COPD) were recruited from the Outpatient Department of Guang'anmen Hospital and Beijing Niujie Health Service Center from April to December, 2023. Participants in both groups attended supervised Five-body balance exercise training twice a week for 12 weeks. Patients with COPD continued their regular medication regimen during the intervention period. The endpoints were mean changes in the 6-min walk test (6MWT), St. George's Respiratory Questionnaire (SGRQ) score, cardiopulmonary exercise testing (CPET), pulmonary function, and scores of COPD assessment test (CAT), modified British Medical Research Council, Self-Rating Anxiety Scale, and Self-Rating Depression Scale from baseline to 12 weeks. Adverse events were monitored throughout the study.

RESULTS

The PRISm group showed a significant improvement from baseline to week 12 in 6MWT, SGRQ symptom score, and forced vital capacity (FVC) compared to the COPD group (P<0.05). No significant between-group changes were observed in other outcome measurements (P>0.05). In addition, compared with baseline, both groups exhibited improvements in 6MWT, SGRQ score, and CPET at week 12 (P<0.05). The PRISm group also showed a significant increase in forced expiratory volume in 1 s and FVC, as well as a significant decrease in CAT score at week 12 (P<0.05). No adverse events were reported.

CONCLUSION

Patients with PRISm may benefit from Five-body balance exercise training, which can improve the exercise capacity, health-related quality of life, and lung function. (Registration No. ChiCTR2200059290).

Association of the non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) with COPD prevalence and all-cause mortality: a population-based study based on NHANES 2007-2016

Background

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) plays a potential role in metabolic and cardiovascular diseases. However, its association with chronic obstructive pulmonary disease (COPD) is not well-defined. Here, we aim to investigate the potential association of NHHR with both the prevalence of COPD and all-cause mortality among individuals with COPD.

Methods

This population-based NHANES (2007-2016) study utilized weighted statistical analyses. Multivariable logistic regression assessed the NHHR-COPD prevalence association, with restricted cubic spline (RCS) testing for non-linearity. The association between NHHR and all-cause mortality in COPD was evaluated using Cox proportional hazards models and Kaplan-Meier, with RCS testing for non-linearity. Subgroup and sensitivity analyses confirmed the findings' reliability.

Results

This study included 6349 participants, of whom 1271 were diagnosed with COPD. Participants in the highest NHHR tertile demonstrated 62% higher odds of COPD prevalence compared to those in the lowest tertile (OR = 1.62, 95% CI:1.11-2.39, P = 0.017). Results from RCS analysis indicated a nonlinear relationship between NHHR and the prevalence of COPD (P for nonlinear = 0.007), with the curve demonstrating an inverted L-shape. Over an average follow-up period of 93 months, 320 participants with COPD died. In the weighted Kaplan-Meier survival analysis, participants with COPD in the lower NHHR tertile demonstrated greater cumulative probability of all-cause mortality compared to higher tertiles (P < 0.001). Weighted multivariable Cox regression models revealed an inverse association between NHHR levels and COPD all-cause mortality, with the highest NHHR tertile showing 11% lower likelihood of COPD all-cause mortality relative to the lowest tertile (HR = 0.89, 95% CI:0.80-0.99, P = 0.027). In addition, RCS analysis demonstrated a significant negative linear association between NHHR levels and all-cause mortality in COPD patients (P for nonlinear = 0.081). Subgroup and sensitivity analyses further confirmed the associations of NHHR on both morbidity and all-cause mortality.

Conclusion

Higher NHHR levels were associated with increased COPD prevalence yet inversely correlated with all-cause mortality in COPD patients. These paradoxical associations underscore the need for COPD-specific lipid management strategies that balance disease progression and mortality risks.

Phenotypes and Trajectories of Tobacco-exposed Persons with Preserved Spirometry: Insights from Lung Volumes

Rationale: Among tobacco-exposed persons with preserved spirometry (TEPSs), we previously demonstrated that different lung volume indices-specifically, elevated total lung capacity (TLC) versus elevated ratio of functional residual capacity to TLC (FRC/TLC)-identify different lung disease characteristics in the COPDGene cohort. Objective: We sought to determine differential disease characteristics and trajectories associated with lung volume indices among TEPSs in the SPIROMICS cohort. Methods: We categorized TEPSs (n = 814) by tertiles (low, intermediate, and high) of TLC or residual volume-to-TLC ratio (RV/TLC) derived from baseline computed tomography images and then examined clinical and spirometric disease trajectories in mutually exclusive categories of participants with high TLC without high RV/TLC ([TLC]high) versus high RV/TLC without high TLC ([RV/TLC]high). We examined differences in computed tomography-measured emphysema (Hounsfield units [HU] ⩽-950; parametric response mapping [PRM] of emphysema), air trapping (HU⩽-856; PRM of functional small airway disease; a disease probability measure for non-emphysematous gas trapping), airway geometry (the mean square root of wall area of a hypothetical airway with 10 mm internal perimeter), respiratory symptoms (on the modified Medical Research Council Dyspnea Scale; COPD Assessment Test [CAT]; St. George's Respiratory Questionnaire [SGRQ]; and Short Form-12 [SF12]), and outcomes (annualized exacerbation rate) between the two categories at baseline and over follow-up time up to 8.5 years, using regression modeling adjusted for age, sex, height, weight, and smoking status (current vs. former smoker) and burden (pack-years). Results: In TEPSs, the pattern of spirometric disease progression differed between participants with [TLC]high and those with [RV/TLC]high: There was increased forced vital capacity with stable forced expiratory volume in 1 second in participants with [TLC]high, versus unchanged forced vital capacity but nominally decreased forced expiratory volume in 1 second in those with [RV/TLC]high. Compared with participants with [TLC]high, TEPSs with [RV/TLC]high had less emphysema (by HU ⩽-950) but more airway disease (by HU ⩽-856; PRM of functional small airway disease; disease probability measure for gas trapping, and mean square root of wall area of a hypothetical airway with 10 mm internal perimeter), more respiratory symptoms (on the modified Medical Research Council Dyspnea Scale, CAT, SGRQ, and SF12), and more severe exacerbations at baseline. Over an average follow-up of 4.1 ± 2.4 years (range = 0.5-8.5 yr), TEPSs with [RV/TLC]high also had a higher likelihood of developing more severe spirometric disease (preserved ratio impaired spirometry or Global Initiative for Chronic Obstructive Lung Disease Classification 2) and worsening of their respiratory symptoms (on the CAT and SGRQ). Although the incidence rates of respiratory exacerbations, hospitalizations, and mortality were not significantly different between the two categories over the follow-up period, TEPSs with [RV/TLC]high were more likely to have been prescribed a respiratory inhaler at their last follow-up visit. Conclusions: In these TEPSs from the SPIROMICS cohort, lung volume stratification by TLC versus RV/TLC identifies two pre-COPD phenotypes with distinct respiratory symptoms, radiographic features, and clinical trajectories. The characteristics of these pre-COPD phenotypes match those previously described in the COPDGene cohort using TLC versus FRC/TLC stratification.

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

Rationale: Chronic lung diseases are associated with increased risk of mortality due to coronary heart disease (CHD). Nonetheless, the population attributable fraction (PAF) of lung function impairment relative to other established cardiovascular risk factors is unclear. Objectives: To evaluate the PAF of low lung function for CHD mortality Methods: We harmonized and pooled lung function and clinical data across eight U.S. general population cohorts. Impaired lung function was defined as forced expiratory volume in 1 second (FEV1) and/or forced vital capacity ≤ 95% predicted on baseline spirometry. The association between CHD mortality and risk factors was assessed using cause-specific proportional hazards and Fine-Gray proportional subdistribution hazard models, treating non-CHD mortality as a competing risk. Models were adjusted for lung function as well as age, sex, race/ethnicity, educational attainment, body mass index, smoking status, pack-years of smoking, diabetes mellitus, high-density lipoprotein, and high low-density lipoprotein (≥130 mg/dl). PAF was calculated as the relative change in the average absolute risk of 10-year CHD mortality by elimination of lung function lower than 95% predicted. Results: Among 35,143 participants, 1,844 of 13,174 (14.0%) deaths were due to CHD. Compared with percentage predicted FEV1 (FEV1pp) > 95%, the subdistribution adjusted hazard ratio for low FEV1pp was 1.30 (95% confidence interval, 1.18-1.44). The PAF for FEV1pp ≤ 95% was 12%, ranking low FEV1 third on the list of PAF for CHD mortality, after hypertension and diabetes. Low FEV1pp ranked second in the subgroup of active smokers (PAF 14%), after hypertension. Conclusions: Low lung function, even in the range considered clinically normal, ranks high on the list of attributable risk factors for CHD mortality and should be considered in cardiovascular risk stratification.

Clinical and Prognostic Differences in Mild to Moderate COPD With and Without Emphysema

BACKGROUND

The clinical and prognostic characteristics of mild-to-moderate COPD with and without emphysema remain inadequately investigated.

RESEARCH QUESTION

Do the clinical and prognostic characteristics differ between mild-to-moderate COPD with and without emphysema?

STUDY DESIGN AND METHODS

We obtained clinical data of 989 participants with mild-to-moderate COPD from the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS). They were categorized into two groups based on their baseline low-attention lung voxels with a density < -950 Hounsfield units of < 5% on CT scans: mild-to-moderate COPD with emphysema (EC) group and mild-to-moderate COPD without emphysema (NEC) group. Linear mixed-effects models were used to assess the differences in the decline of lung function, health-related quality of life, and quantitative CT indexes between these two groups. Zero-inflated negative binomial regressions were used to evaluate the rates of acute respiratory exacerbations between the groups.

RESULTS

Among participants with mild-to-moderate COPD, 428 (43.3%) exhibited emphysema on CT scans. The annual decline in FEV1 was -56.1 mL/y for the EC group and -46.9 mL/y for the NEC group, with a nonsignificant between-group difference of 9.1 mL/y (95% CI, -24.0 to 5.7 mL/y). The rate of emphysema progression in the EC group was significantly lower than in the NEC group (natural logarithm(%LAA-950), -0.173%; 95% CI, -0.252% to -0.094%). The EC group also showed a more pronounced annual increase in the St. George's Respiratory Questionnaire score (0.9 points) compared with the NEC group. The EC group had a higher rate of acute respiratory exacerbations (0.36 per person-year) than the NEC group (0.25 per person-year), with a rate ratio of 1.42 (95% CI, 1.27-1.54).

INTERPRETATION

The EC group did not have accelerated rates of decline in FEV1, but they experienced significantly worse health-related quality of life and a higher rate of acute respiratory exacerbations. The nonemphysema subtype demonstrated increased emphysema progression.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT01969344; URL: www.

CLINICALTRIALS

gov.

Smoking and outcomes in candidates for liver transplantation: Analysis of the Pulmonary Vascular Complications of Liver Disease 2 (PVCLD2)

Patients with chronic liver disease commonly have abnormal lung function; however, the impact of smoking on outcomes in these patients is unknown. We hypothesized current or past smoking would be associated with worse survival in patients with advanced liver disease. The Pulmonary Vascular Complications in Liver Disease Study 2 (PVCLD2) was a prospective cohort of patients with advanced liver disease undergoing evaluation for liver transplantation (LT). Patients were classified by self-report as a "non-smoker," "past smoker," or "current smoker." We used Cox proportional hazards models and Fine-Gray models with LT as a competing risk. Models were adjusted for age, sex, body mass index, race, family income, liver disease etiology, and Model for End-Stage Liver Disease-Sodium score. Of the 410 patients included, most (65%) were male and the mean age at enrollment was 56.5 years. One hundred sixty (39%) patients were nonsmokers, 183 (45%) were past smokers, and 67 (16%) were current smokers. In total, 151 (37%) patients received an LT, and 88 (20%) patients died. When compared to nonsmokers, current smokers had a 2.17-fold increase in risk of death overall (95% CI: 1.12-4.18, p = 0.02). There was a 7% increase in overall risk of death for every 5 pack-years increase (95% CI: 1.01-1.13, p = 0.02). With LT as a competing risk, the subdistributional HR of current smokers versus nonsmokers for death was 2.45 (95% CI: 1.31-4.60, p = 0.005). In this model, past smokers displayed a nonsignificant increase in the risk of death compared to nonsmokers (subdistributional HR: 1.58, 95% CI: 0.91-2.72, p = 0.10). Patients with advanced liver disease undergoing evaluation for LT who smoke have an increased risk of death. Smoking cessation could lead to improved overall survival with or without LT.

Novel association between chronic obstructive pulmonary disease and osteoporosis: A prospective cross-sectional study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory condition often associated with a high incidence of osteoporosis. Studies indicate that patients with COPD present with a significant decrease in bone mineral density (BMD), potentially related to inflammation and corticosteroid use.

AIM

To investigate the relationship between BMD and lung function, mainly the forced expiratory volume in the forced expiratory volume in 1 second (FEV1)/ forced vital capacity percentage (FVC%), in patients with COPD using quantitative computed tomography (QCT).

METHODS

This prospective cross-sectional study included 85 patients with COPD treated at Gansu Provincial People's Hospital. Exposure variables included lung function parameter (FEV1/FVC%), age, sex, body mass index, smoking status, tea-drinking habits, and physical activity. BMD was measured using QCT. Linear regression and generalized additive models were employed to analyze the relationship between exposure variables and BMD.

RESULTS

Linear regression analysis revealed a significant positive relationship between BMD and FEV1/FVC% (β = 0.1, 95% confidence interval [CI]: 0.1-0.1; P < 0.0001). Non-linear analysis identified a unique BMD breakpoint of 128.08 mg/cm³. Before the breakpoint, BMD was significantly positively correlated with FEV1/FVC% (β = 0.245; P = 0.0019); while after the breakpoint, the relationship was negative and showed no statistical significance (β = -0.136; P = 0.0753). This finding underscores the critical role of BMD in COPD management and highlights the importance of individualized clinical interventions in improvement of lung function and overall health status in patients.

CONCLUSION

There is a complex non-linear relationship between BMD and lung function in patients with COPD, highlighting the importance of monitoring change in bone density during the management of COPD.

Associations between life-course FEV1/FVC trajectories and respiratory symptoms up to middle age: analysis of data from two prospective cohort studies

BACKGROUND

Life-course lung function trajectories leading to airflow obstruction, as measured by impaired FEV1/FVC (forced vital capacity), precede the onset of chronic obstructive pulmonary disease (COPD). We aimed to investigate whether individuals on impaired FEV1/FVC trajectories have an increased burden of respiratory symptoms, including those who do not meet the spirometric criteria for COPD.

METHODS

We analysed serial life-course data from two population-based cohort studies separately, which included respiratory symptoms and spirometry: the Tasmanian Longitudinal Health Study (TAHS, Australia) cohort was recruited at age 6-7 years and followed up until middle age (mean age 53 years; range 51-55); and the Coronary Artery Risk Development in Young Adults (CARDIA, USA) cohort was recruited at a mean age of 25 years (range 18-30) and followed up to a mean age of 55 years (range 47-64). Participants' symptom profiles at ages 53 and 55 years were derived by latent class analysis. Symptom profiles were compared across pre-bronchodilator FEV1/FVC trajectories derived by group-based modelling, then restricted to those without COPD defined by post-bronchodilator airflow obstruction (FEV1/FVC <5th percentile) at ages 51-55 years and 47-64 years.

FINDINGS

Six FEV1/FVC trajectories previously derived for TAHS were replicated in CARDIA. Optimal models identified five symptom profiles in TAHS (n=2421) and six in CARDIA (n=3153). For both cohorts, the most impaired FEV1/FVC trajectory (early low, rapid decline in TAHS; low peak, rapid decline in CARDIA) was associated with predominant wheeze (multinomial odds ratio [mOR] 6·71 [95% CI 4·10-10·90] in TAHS and 9·90 [4·52-21·70] in CARDIA) and nearly all respiratory symptoms (4·95 [2·52-9·74] and 14·80 [5·97-36·60]) at age 51-55 years in TAHS and age 47-64 years in CARDIA, compared with the average trajectory. Among individuals belonging to the three most impaired trajectories, the associations with predominant wheeze increased with worsening FEV1/FVC impairment and persisted when considering only those without spirometry-defined COPD. Additionally, for those belonging to the two rapid decline trajectories, both wheezing and usual phlegm or bronchitis were reported by 54 (20%) of 265 participants younger than 14 years in TAHS and by 31 (25%) of 123 participants aged 30 years or younger in CARDIA.

INTERPRETATION

In two independent cohorts that collected similar data, people on impaired FEV1/FVC trajectories often had a longstanding history of both wheeze and phlegm or bronchitis, and wheeze was the predominant symptom in individuals aged 47-64 years among those who had not already progressed to COPD.

FUNDING

National Health and Medical Research Council (Australia); The University of Melbourne; Clifford Craig Medical Research Trust; Victorian, Queensland & Tasmanian Asthma Foundations; Royal Hobart Hospital Research Foundation; Helen MacPherson Smith Trust; GlaxoSmithKline; National Heart, Lung, and Blood Institute of the US National Institutes of Health.

Asthma and respiratory comorbidities

Asthma is a common respiratory condition with various phenotypes, nonspecific symptoms, and variable clinical course. The occurrence of other respiratory conditions with asthma, or respiratory comorbidities (RCs), is not unusual. A literature search of PubMed was performed for asthma and a variety of respiratory comorbidities for the years 2019 to 2024. The 5 conditions with the largest number of references, other than rhinitis and rhinosinusitis (addressed elsewhere), or that are the most problematic in the authors' clinical experience, are summarized. Others are briefly discussed. The diagnosis and treatment of both asthma and RCs are complicated by the overlap of symptoms and signs. Recognizing RCs is especially problematic in adult-onset, non-type 2 asthma because there are no biomarkers to assist in confirming non-type 2 asthma. Treatment decisions in subjects with suspected asthma and RCs are complicated by the potential similarities between the symptoms or signs of the RC and asthma, the absence of a sine quo non for the diagnosis of asthma, the likelihood that many RCs improve with systemic corticosteroid therapy, and the possibility that manifestations of the RCs are misattributed to asthma or vice versa. Recognition of RCs is critical to the effective management of asthma, particularly severe or difficult-to-treat asthma.

Serum Immunoglobulin G Levels Are Associated with Risk for Exacerbations: An Analysis of SPIROMICS

Rationale: Serum IgG deficiency is associated with morbidity in chronic obstructive pulmonary disease (COPD), but it is unclear whether concentrations in the lower end of the normal range still confer risk. Objectives: To determine if levels above traditional cutoffs for serum IgG deficiency are associated with exacerbations among current and former smokers with or at risk for COPD. Methods: Former and current smokers in SPIROMICS (the Subpopulations and Intermediate Outcome Measures of COPD study) (n = 1,497) were studied: 1,026 with COPD and 471 at risk for COPD. In a subset (n = 1,031), IgG subclasses were measured. Associations between total IgG or subclasses and prospective exacerbations were evaluated with multivariable models adjusting for demographic characteristics, current smoking, smoking history, FEV1 percent predicted, inhaled corticosteroids, and serum IgA. Measurements and Main Results: The 35th percentile (1,225 mg/dl in this cohort) of IgG was the best cutoff by Akaike information criterion. Below this, there was increased exacerbation risk (incidence rate ratio [IRR], 1.28; 95% confidence interval [CI], 1.08-1.51). Among subclasses, IgG1 and IgG2 below the 35th percentile (354 and 105 mg/dl, respectively) were associated with increased risks of severe exacerbation (IgG1, IRR, 1.39; 95% CI, 1.06-1.84; IgG2, IRR, 1.50; 95% CI, 1.14-1.1.97). These associations remained significant when additionally adjusting for a history of exacerbations. Conclusions: Lower serum IgG is prospectively associated with exacerbations in individuals with or at risk for COPD. Among subclasses, lower IgG1 and IgG2 are prospectively associated with severe exacerbations. The optimal IgG cutoff was substantially higher than traditional cutoffs for deficiency, suggesting that subtle impairment of humoral immunity may be associated with exacerbations.

Muscle Mass Index Decline as a Predictor of Lung Function Reduction in the General Population

BACKGROUND

This study explores the link between muscle mass decline and lung function deterioration, which can worsen respiratory health by reducing exercise capacity and quality of life. The relationship between muscle mass index (MMI) changes and lung function in the general population remains unclear, especially as muscle mass fluctuates with aging. We aimed to clarify this dynamic relationship by examining how changes in muscle mass impact pulmonary function and the development of respiratory symptoms.

METHODS

We utilized the Ansan and Ansung Cohort Study of the Korean Genome and Epidemiology Study (KoGES) database, a large-scale prospective cohort, enrolling participants aged 40 to 69 years with lung function and body composition measurements. Over 12 years, data were collected biannually. The study assessed associations between changes in MMI and lung function trends, with cT1-T3 calculated using the linear regression coefficient and stratified by tertile. Survival analysis was then performed to examine differences in time to first airflow obstruction (AFO) and exacerbation among the tertiles.

RESULTS

A total of 2956 participants were enrolled in this study. At baseline, participants with higher MMI tended to be younger, had fewer co-morbidities and exhibited better lung function. Those with a steeper MMI decline rate exhibited a more rapid forced expiratory volume in 1 s (FEV1) decline over a 12-year follow-up (cT1: 43.3 mL/year, cT2: 38.4 mL/year, cT3: 33.2 mL/year, p < 0.001). Forced vital capacity (FVC) decline were more pronounced in groups with greater MMI decline rates (cT1: 38.5 mL/year, cT2: 32.8 mL/year, cT3: 26.0 mL/year, p < 0.001). Although, the time to first AFO did not differ significantly among T1-T3 groups, the time to first exacerbation related to wheezing event was significantly lower in cT3 group than in cT1 group (HR: 0.786, 95% CI: 0.629, 0.982).

CONCLUSIONS

A faster decline in MMI was associated with more rapid decline of both FEV1 and FVC and a higher risk of developing exacerbations of respiratory symptom. Although AFO was not associated with changes in MMI, further research is needed to explore the long-term relationships between muscle mass and the effects of preventive interventions aimed at maintaining muscle mass and respiratory health.

Self-reported dyspnea and interest in a respiratory muscle training program among callers to the New York State Quitline

INTRODUCTION

Cigarette smoking is an important risk factor in the development of dyspnea. Programs designed to strengthen the respiratory muscles can improve dyspnea in people with or without lung disease. As a first step in understanding the feasibility of offering a respiratory muscle training (RMT) program to people who are seeking help to try to quit smoking, we asked callers who contacted the New York State Quitline about their dyspnea and potential interest in a home-based RMT program.

METHODS

Consecutive callers who contacted the New York State Quitline (n=1019) between 19 May and 9 June 2023 completed the Modified Medical Research Council (mMRC) dyspnea scale and reported their level of interest in RMT. Participants were categorized as: high breathlessness (HB: 0-1), or low breathlessness (LB: 2-4). We examined characteristic differences between participants who reported HB versus LB and examined differences in level of interest in home-based RMT.

RESULTS

Those with HB were older [mean (SD): 61.3 (12.5) vs 53.6 (15.0) years, p<0.001], had more cumulative years of smoking [38.8 (15.1) vs 28.8 (15.4) years, p<0.001], smoked more cigarettes per day [19.3 (10.5) vs 17.3 (8.8), p<0.01], reported more disability (p<0.001) and chronic health conditions (78.5% vs 53.9%, p<0.001). Those with HB also expressed greater interest in RMT [7.8 (3.3) vs 6.2 (4.1), p<0.001].

CONCLUSIONS

These preliminary findings suggest that about 20% of quitline callers report clinically significant levels of breathlessness and most respondents, regardless of their level of breathlessness, report interest in a home-based RMT program, underscoring a potential opportunity to offer this program along with cessation support.

Comparing spirometry, impulse oscillometry with computed tomography for assessing small airway dysfunction in subjects with and without chronic obstructive pulmonary disease

BACKGROUND

Studies on consistency among spirometry, impulse oscillometry (IOS), and histology for detecting small airway dysfunction (SAD) remain scarce. Considering invasiveness of lung histopathology, we aimed to compare spirometry and IOS with chest computed tomography (CT) for SAD detection, and evaluate clinical characteristics of subjects with SAD assessed by these three techniques.

METHODS

We collected baseline data from the Early COPD (ECOPD) study. CT-defined SAD was defined as parametric response mapping quantifying SAD (PRMfSAD) ≥ 15%. Spirometry-defined SAD was defined as at least two of maximal mid-expiratory flow (MMEF), forced expiratory flow 50% (FEF50), and forced expiratory flow 75% (FEF75) less than 65% of predicted. IOS-defined SAD was defined as peripheral airway resistance R5 - R20 > 0.07 kPa/L/s. The consistency of spirometry, IOS and CT for diagnosing SAD was assessed using Kappa coefficient. Correlations among the three techniques-measured small airway function parameters were assessed by Spearman correlation analysis.

RESULTS

2055 subjects were included in the final analysis. There was low agreement in SAD assessment between spirometry and CT (Kappa = 0.126, 95% confidence interval [CI]: 0.106 to 0.146, p < 0.001), between IOS and CT (Kappa = 0.266, 95% CI: 0.219 to 0.313, p < 0.001), as well as among spirometry, IOS, and CT (Kappa = 0.056, 95% CI: 0.029 to 0.082, p < 0.001). The correlation was moderate (|r|: 0.5 to 0.7, p < 0.05) between spirometry and CT-measured small airway function parameters, and weak (|r|< 0.4, p < 0.05) between IOS and CT-measured small airway function parameters. Only spirometry-defined SAD group had more lower lung function (FEV1/FVC: adjusted difference=-10.7%, 95% CI: -13.5% to -7.8%, p < 0.001) and increased airway wall thickness (Pi 10: adjusted difference = 0.3 mm, 95% CI: 0 to 0.6 mm, p = 0.046) than only CT-defined SAD group. Only IOS-defined SAD group had better lung function (FEV1/FVC: adjusted difference = 3.9%, 95% CI: 1.9 to 5.8%, p < 0.001), less emphysema (inspiratory LAA- 950: adjusted difference=-2.1%, 95% CI:-3.1% to -1.1%, P < 0.001; PRMEmph: adjusted difference=-2.3%, 95% CI: -3.2% to -1.4%, p < 0.001), and thicker airway wall (Pi 10: adjusted difference = 0.2 mm, 95% CI: 0.1 mm to 0.4 mm, p = 0.005) than only CT-defined SAD group.

CONCLUSIONS

There was low consistency in the assessment of SAD between spirometry and CT, between IOS and CT, as well as among spirometry, IOS, and CT.

CLINICAL TRIAL NUMBER

Not applicable.

Preserved ratio impaired spirometry: clinical, imaging and artificial intelligence perspective

Preserved ratio impaired spirometry (PRISm) is a pulmonary function pattern characterized by a forced expiratory volume in one second (FEV1) to forced vital capacity ratio greater than 0.70, with an FEV1 that is below 80% of the predicted value, even after the use of bronchodilators. PRISm is considered a form of "Pre-Chronic Obstructive Pulmonary Disease (Pre-COPD)" within the broader scope of COPD. Clinically, it presents with respiratory symptoms and is more commonly observed in individuals with high body mass index, females, and those who are current smokers. Additionally, it is frequently associated with metabolic disorders and cardiovascular diseases. Regarding prognosis, PRISm shows considerable variation, ranging from improvement in lung function to the development of COPD. In this article, we review the epidemiology, comorbidities, and clinical outcomes of PRISm, with a particular emphasis on the crucial role of imaging assessments, especially computed tomography scans and magnetic resonance imaging (MRI) technology, in diagnosing, evaluating, and predicting the prognosis of PRISm. Comprehensive imaging provides a quantitative evaluation of lung volume, density, airways, and vasculature, while MRI technology can directly quantify ventilation function and pulmonary blood flow. We also emphasize the future potential of X-ray technology in this field. Moreover, the article discusses the application of artificial intelligence, including its role in predicting PRISm subtypes and modeling ventilation function.

A machine learning model and identification of immune infiltration for chronic obstructive pulmonary disease based on disulfidptosis-related genes

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a chronic and progressive lung disease. Disulfidptosis-related genes (DRGs) may be involved in the pathogenesis of COPD. From the perspective of predictive, preventive, and personalized medicine (PPPM), clarifying the role of disulfidptosis in the development of COPD could provide a opportunity for primary prediction, targeted prevention, and personalized treatment of the disease.

METHODS

We analyzed the expression profiles of DRGs and immune cell infiltration in COPD patients by using the GSE38974 dataset. According to the DRGs, molecular clusters and related immune cell infiltration levels were explored in individuals with COPD. Next, co-expression modules and cluster-specific differentially expressed genes were identified by the Weighted Gene Co-expression Network Analysis (WGCNA). Comparing the performance of the random forest (RF), support vector machine (SVM), generalized linear model (GLM), and eXtreme Gradient Boosting (XGB), we constructed the ptimal machine learning model.

RESULTS

DE-DRGs, differential immune cells and two clusters were identified. Notable difference in DRGs, immune cell populations, biological processes, and pathway behaviors were noted among the two clusters. Besides, significant differences in DRGs, immune cells, biological functions, and pathway activities were observed between the two clusters.A nomogram was created to aid in the practical application of clinical procedures. The SVM model achieved the best results in differentiating COPD patients across various clusters. Following that, we identified the top five genes as predictor genes via SVM model. These five genes related to the model were strongly linked to traits of the individuals with COPD.

CONCLUSION

Our study demonstrated the relationship between disulfidptosis and COPD and established an optimal machine-learning model to evaluate the subtypes and traits of COPD. DRGs serve as a target for future predictive diagnostics, targeted prevention, and individualized therapy in COPD, facilitating the transition from reactive medical services to PPPM in the management of the disease.

Functionally important respiratory symptoms and continued cigarette use versus e-cigarette switching: population assessment of tobacco and health study waves 2-6

Background

Substitution of noncombustible tobacco products for cigarettes could improve respiratory symptoms. We hypothesized that complete cigarette-to-e-cigarette switching would improve respiratory symptoms compared to continued smoking.

Methods

Longitudinal analysis of data from waves 2-6 (W2-W6; 2014-2021) of the Population Assessment of Tobacco and Health (PATH) Study, an observational cohort study that surveyed 5653 US adults ≥18 years without COPD/chronic bronchitis/emphysema. We compiled 14,947 two-wave (1-2 year) observations with persons who smoked cigarettes at baseline and compared the relation between functionally important respiratory symptoms and switching to exclusive e-cigarette use or quitting tobacco versus continued cigarette use (reference). A 9-point wheezing/nighttime cough index was dichotomized based on index scores of ≥2 or ≥3, previously associated with poorer functional health. Multivariable models assessed how changes in cigarette use predicted worsening/improvement of symptoms.

Findings

Among those with an index score <2, 3.5% switched to e-cigarettes, and 11.1% quit all tobacco. Functionally important respiratory symptoms worsened (≥2 at follow-up) in 15.4%, 10.0% and 10.1% of those who continued cigarettes, switched to e-cigarettes, and quit, respectively. Adjusted relative risk (RR) for respiratory symptom worsening was 0.69 (95% confidence interval (CI), 0.52, 0.91) for e-cigarette switching and 0.73 (95% CI, 0.54, 0.97) for quitting. Of persons with index score ≥2, 2.8% switched to e-cigarettes, and 6.7% quit. Respiratory symptoms improved (<2 at follow-up) in 27.7%, 45.8% and 42.1% of those who continued cigarettes, switched to e-cigarettes, and quit, respectively. The RR for improving was 1.31 (95% CI, 1.05, 1.64) for e-cigarette switching and 1.36 (95% CI, 1.15, 1.62) for quitting. The RRs for exclusive e-cigarette use with a cutoff of ≥3 for respiratory symptom worsening and improvement were not significant (0.74 [0.53, 1.05] and 1.20 [0.95, 1.51] respectively) but were significant in an unweighted analysis that included partial data for individuals lost to follow-up (0.74 [0.57, 0.95] and 1.21 [1.06, 1.39] respectively).

Interpretation

Switching completely from past 30-day use of cigarettes to e-cigarettes had short-term beneficial associations with functionally important respiratory symptoms similar to quitting tobacco completely.

Funding

This manuscript is supported with Federal funds from the National Institute on Drug Abuse (NIDA) at the National Institutes of Health (NIH), and the Center for Tobacco Products (CTP) at the Food and Drug Administration (FDA), Department of Health and Human Services, under contract to Westat (contract nos. HHSN271201100027C and HHSN271201600001C), and through an interagency agreement between NIH NIDA and FDA CTP. Heather L. Kimmel was substantially involved in the scientific management of and providing scientific expertise for contract nos. HHSN271201100027C and HHSN271201600001C.

Clinical Characteristics of Chronic Obstructive Pulmonary Disease according to Smoking Status

Chronic obstructive pulmonary disease (COPD) can be caused by various factors, including lung infections, asthma, air pollution, childhood growth disorders, and genetic factors, though smoking is the predominant risk factor. The main pathological mechanisms in COPD involve small airway disease, emphysema, mucus hypersecretion, and vascular disorders. COPD in non-smokers is characterized by a normal 1-second forced expiratory volume decline, equal sex distribution, younger age of onset, fewer comorbidities, milder airflow obstruction, preserved diffusing capacity of the lungs for carbon monoxide, and radiological features such as more air-trapping and less severe emphysema compared to COPD in smokers. Nevertheless, non-smokers with COPD still experience a high prevalence of acute exacerbations, nearly equal to that of smokers with COPD. Moreover, COPD itself is an independent risk factor for developing lung cancer, regardless of smoking status. Given that COPD coexists with numerous comorbidities, effectively managing these comorbidities is crucial, requiring multifaceted efforts for comprehensive treatment.

Demographic and Clinical Characteristics of Mild, Young and Early COPD: A Cross-Sectional Analysis of 5468 Patients

Early, mild and young COPD concepts are not clearly defined and are often used interchangeably to refer to the onset of the disease. Objective: To describe and compare the characteristics of mild, young and early COPD in a large sample of COPD from primary and secondary care. Methods: Pooled analysis of individual data from four multicenter observational studies of patients with stable COPD (≥40 years, FEV1/FVC < 0.7, smoking ≥ 10 pack-years). Mild COPD was defined as FEV1% ≥ 65%; young COPD as <55 years; and early COPD as <55 years and smoking ≤ 20 pack-years. The relationship between FEV1(%), age and pack-years was analyzed with linear regression equations. Results: We included 5468 patients. Their mean age was 67 (SD: 9.6) years, and 85% were male. A total of 1158 (21.2%) patients had mild COPD; 636 (11.6%) had young COPD and 191 (3.5%) early COPD. The three groups shared common characteristics: they were more frequently female, younger and with less tobacco exposure compared with the remaining patients. Early COPD had fewer comorbidities and fewer COPD admissions, but no significant differences were found in ambulatory exacerbations. In linear regression analysis, the decline in FEV1(%) was more pronounced for the first 20 pack-years for all age groups and was even more important in younger patients. Conclusions: Mild, young and early COPD patients were more frequently women. The steepest decline in FEV1(%) was observed in individuals <55 years and smoking between 10 and 20 pack-years (early COPD), which highlights the importance of an early detection and implementation of preventive and therapeutic measures.

Chronic Airflow Limitation, Emphysema, and Impaired Diffusing Capacity in Relation to Smoking Habits in a Swedish Middle-aged Population

Rationale: Chronic obstructive pulmonary disease (COPD) includes respiratory symptoms and chronic airflow limitation (CAL). In some cases, emphysema and impaired diffusing capacity of the lung for carbon monoxide (DlCO) are present, but characteristics and symptoms vary with smoking exposure. Objective: To study the prevalence of CAL, emphysema, and impaired DlCO in relation to smoking and respiratory symptoms in a middle-aged population. Methods: We investigated 28,746 randomly invited individuals (52% women) aged 50-64 years across six Swedish sites. We performed spirometry, DlCO testing, and high-resolution computed tomography and asked for smoking habits and respiratory symptoms. CAL was defined as post-bronchodilator forced expiratory volume in 1 second divided by forced vital capacity (FEV1/FVC) < 0.7. Results: The overall prevalence was 8.8% for CAL, 5.7% for impaired DlCO (DlCO < LLN), and 8.8% for emphysema, with a higher prevalence in current smokers than in ex-smokers and never-smokers. The proportion of never-smokers among those with CAL, emphysema, and impaired DlCO was 32%, 19%, and 31%, respectively. Regardless of smoking habits, the prevalence of respiratory symptoms was higher among people with CAL and impaired DlCO than those with normal lung function. Asthma prevalence in never-smokers with CAL was 14%. In this group, asthma was associated with lower FEV1 and more respiratory symptoms. Conclusions: In this large population-based study of middle-aged people, CAL and impaired DlCO were associated with common respiratory symptoms. Self-reported asthma was not associated with CAL in never-smokers. Our findings suggest that CAL in never-smokers signifies a separate clinical phenotype that may be monitored and, possibly, treated differently from smoking-related COPD.

Lung structure and longitudinal change in cardiac structure and function: the MESA COPD Study

BACKGROUND

Lung structure and cardiac structure and function are associated cross-sectionally. The classic literature suggests relationships of airways disease to cor pulmonale and emphysema to reduced cardiac output (CO) but longitudinal data are lacking.

METHODS

The Multi-Ethnic Study of Atherosclerosis (MESA) COPD Study was a multicentre longitudinal COPD case-control study of participants 50-79 years with ≥10 pack-years smoking without clinical cardiovascular disease. Segmental airway wall area (WA) and percent emphysema were measured on computed tomography. Right and left ventricle parameters were assessed on cardiac magnetic resonance imaging (cMRI) in exams 6 years apart. Longitudinal and period cross-sectional associations were evaluated with mixed models adjusted for demographics, body size and smoking.

RESULTS

The 187 participants with repeated cMRI were 67±7 years old; 42% had COPD; 22% currently smoked; and the race/ethnicity distribution was 54% White, 30% Black, 14% Hispanic and 3% Asian. Greater WA at enrolment was associated with longitudinal increase in right ventricular (RV) mass (3.5 (95% CI 1.1-5.9) g per 10 mm2 WA). Greater percent emphysema was associated with stably lower left ventricular (LV) end-diastolic volume (-7.8 (95% CI -10.3- -3.0) mL per 5% emphysema) and CO (-0.2 (95% CI -0.4- -0.1) L·min-1 per 5% emphysema).

CONCLUSION

Cardiac associations varied by lung structure over 6 years in this multi-ethnic study. Greater WA at enrolment was associated with longitudinal increases in RV mass, whereas greater percent emphysema was associated with stable decrements in LV filling and CO.

Application of the European Respiratory Society/American Thoracic Society Spirometry Standards and Race-Neutral Equations in the COPDGene Study

Rationale: For spirometry interpretation, the European Respiratory Society (ERS) and American Thoracic Society (ATS) recommend using z-scores, and the ATS has recommended using Global Lung Initiative (GLI) "Global" race-neutral reference equations. However, these recommendations have been variably implemented, and the impact has not been widely assessed in clinical or research settings. Objectives: To evaluate the ERS/ATS classification of airflow obstruction severity. Methods: In COPDGene (Genetic Epidemiology of COPD Study) (N = 10,108), airflow obstruction has been defined by an FEV1/FVC ratio <0.70, with spirometric severity graded from class 1 to class 4 based on race-specific percent predicted (pp) FEV1 cutoff points as recommended by the Global Initiative for Chronic Obstructive Lung Disease (GOLD). We compared the GOLD approach, using National Health and Nutrition Examination Survey III race-specific equations, versus the application of GLI Global equations using the ERS/ATS definition of airflow obstruction as an FEV1/FVC ratio below the lower limit of normal and z-score-based FEV1 cutoff points of -1.645, -2.5, and -4 ("zGLI Global"). We tested the four-tier severity scheme for association with chronic obstructive pulmonary disease outcomes. Measurements and Main Results: The lowest agreement between ERS/ATS with zGLI Global and the GOLD classification was observed in individuals with milder disease (56.9% and 42.5% in GOLD stages 1 and 2, respectively), and race was a major determinant of redistribution. After adjustment for relevant covariates, zGLI Global distinguished all-cause mortality risk between normal spirometry and the first grade of chronic obstructive pulmonary disease (hazard ratio, 1.23; 95% confidence interval, 1.04-1.44; P = 0.014) and showed a linear increase in exacerbation rates with increasing disease severity in comparison with GOLD. Conclusions: The zGLI Global severity classification outperformed the GOLD criteria in the discrimination of survival, exacerbations, and imaging characteristics.

Understanding the Gaps in the Reporting of COPD Exacerbations by Patients: A Review

Exacerbations of chronic obstructive pulmonary disease (COPD) are associated with loss of lung function, poor quality of life, loss of exercise capacity, risk of serious cardiovascular events, hospitalization, and death. However, patients underreport exacerbations, and evidence suggests that unreported exacerbations have similar negative health implications for patients as those that are reported. Whilst there is guidance for physicians to identify patients who are at risk of exacerbations, they do not help patients recognise and report them. Newly developed tools, such as the COPD Exacerbation Recognition Tool (CERT) have been designed to achieve this objective. This review focuses on the underreporting of COPD exacerbations by patients, the factors associated with this, the consequences of underreporting, and potential solutions.

COPD is associated with increased cardiovascular disease risk independent of phenotype

BACKGROUND AND OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is a leading cause of death worldwide that frequently presents with concomitant cardiovascular diseases. Despite the pathological distinction between individual COPD phenotypes such as emphysema and chronic bronchitis, there is a lack of knowledge about the impact of COPD phenotype on cardiovascular disease risk. Thus, this study aimed to utilize a nationally representative sample to investigate cardiovascular disease prevalence in patients with COPD with emphysema and chronic bronchitis phenotypes.

METHODS

Data from 31,560 adults including 2504 individuals with COPD, collected as part of the National Health and Nutrition Examination Survey (1999-2018), were examined.

RESULTS

A significantly increased cardiovascular disease risk, including coronary heart disease, heart failure, myocardial infarction and stroke, was identified in patients with COPD among all disease phenotypes. Particularly, compared to those without COPD, individuals with chronic bronchitis presented with 1.76 (95% CI: 1.41-2.20) times greater odds, individuals with emphysema with 2.31 (95% CI: 1.80-2.96) times greater odds, while those with a concurrent phenotype (combined chronic bronchitis and emphysema) exhibited 2.98 (95% CI: 2.11-4.21) times greater odds of reporting cardiovascular diseases.

CONCLUSION

Our data confirms that patients with COPD present an elevated risk of developing cardiovascular disease among all phenotypes, with the most marked increase being in those with concurrent chronic bronchitis and emphysema phenotypes. These findings emphasize the need for awareness and appropriate cardiovascular screening in COPD.

COPD Risk Phenotypes in Older Smokers: Evaluation in GLI- and GOLD-Defined Respiratory Impairment

PURPOSE

In aging populations, the Global Initiative for Obstructive Lung Disease (GOLD) spirometry threshold may misclassify normal spirometry as airflow limitation. The Global Lung Initiative (GLI) method provides age-adjusted criteria. We investigated how the use of GOLD or GLI thresholds in an algorithm affects the classification of elderly smokers into COPD risk phenotypes.

METHODS

Using a modified COPDGene algorithm, including exposure, symptoms, and abnormal spirometry, 200 smokers aged 60 years and older were classified into 4 mutually exclusive phenotypes: Phenotype A (no symptoms, normal spirometry; reference), Phenotype B (symptoms, normal spirometry; possible COPD), Phenotype C (no symptoms, abnormal spirometry; possible COPD), and Phenotype D (symptoms, abnormal spirometry; probable COPD). Abnormal spirometry was defined according to the GOLD or GLI criteria. A comparison was made between the GOLD- and GLI-defined phenotypes.

RESULTS

Using GLI criteria/cut-offs, 18.5% (n = 37) had phenotype A (no COPD), 42% (n = 84) had phenotype B (possible COPD), 7.5% (n = 15) had phenotype C (possible COPD), and 32% (n = 64) had phenotype D (probable COPD). Using GOLD criteria cut-offs, 14.5% (n-29) had phenotype A (no COPD); 31% (n = 62) had phenotype B, 11.5% (n = 23) had phenotype C (probable COPD), and 43% (n = 86) had phenotype D (probable COPD). Eight smokers with GOLD phenotype C were reclassified as GLI phenotype A, while 22 with GOLD phenotype D were reclassified as GLI phenotype B. Smokers identified as ‟probable COPD" by GOLD alone (potential false positives) had better spirometry results than those identified as ‟probable COPD" by both GOLD and GLI.

CONCLUSION

The use of the GOLD threshold in an algorithm resulted in older smokers being classified into more severe COPD risk phenotypes compared to the GLI threshold. This suggests that GOLD may misclassify smokers with less affected phenotypes as having respiratory impairment, potentially leading to unnecessary and harmful treatments.

Update of prognosis and characteristics of chronic obstructive pulmonary disease in a real-world setting: a 5-year follow-up analysis of a multi-institutional registry

BACKGROUND

We conducted a prospective observational study to elucidate the long-term prognosis and management of chronic obstructive pulmonary disease (COPD) in clinical practice in Japan in the mid-2010s.

METHODS

This prospective cohort study included 29 facilities. Data from 427 patients clinically diagnosed with COPD, enrolled between September 2013 and April 2016, were analyzed. Interstitial pneumonia was excluded through a central multidisciplinary discussion. Follow-up data were collected for up to 5 years after patient registration.

RESULTS

At the time of registration, 53 patients clinically diagnosed with COPD did not have airflow limitation (AFL). In the cohort with AFL (n = 374), 232 patients completed a 5-year follow-up, while 49 patients died during the 1576.6 person-years of observation. The mean age was 71.7 years with an overall 5-year survival rate of 85.4%. Stratified by % forced expiratory volume in one second (FEV1), survival rates were 93.6% in the mild and moderate AFL group, 82.5% in the severe AFL group, and 66.1% in the very severe AFL group. The prognosis of the subpopulation without AFL was poor with a 5-year survival of 81.6%. This subpopulation exhibited respiratory symptoms, low vital capacity and total lung capacity, and emphysematous changes.

CONCLUSIONS

Our study presents the 5-year survival and real-world clinical practice scenario of a prospective cohort of patients clinically diagnosed with COPD in Japan in the mid-2010s. The survival rates of our cohort were numerically better than the Japanese cohort in the 1990s, regardless of the high median age of this cohort. Overall, 12.4% of the patients in this cohort with no AFL at registration exhibited respiratory symptoms and distinct spirometric patterns, and had a poor prognosis.

Diagnostic value of CT in patients with stable chronic obstructive pulmonary disease at high altitude: Observational study

This research aims to explore the diagnostic value of computed tomography (CT) indicators in patients with stable chronic obstructive pulmonary disease (COPD) in a plateau of China, and to find out the correlation between CT indexes and lung function and symptoms. This study screened out 53 stable COPD patients and 53 healthy people through inclusion and exclusion criteria in Hongyuan county, Aba Prefecture, Sichuan Province, between July 2020 and December 2020, and then collected their baseline data, conducted lung function tests and chest CT scans, and collected COPD Assessment Test (CAT), modified Medical Research Council Dyspnea Scale (mMRC) scores. The CT indexes of the 2 groups were compared, binary logistic regression was used to analyze the influence of COPD, the receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of the CT indexes for COPD. The Spearman test was used to understand the correlation analysis between the CT indexes and lung function, symptom score, and the number of acute exacerbations. Multiple linear regression was used to analyze the influencing factors of lung function. The percentage of low-attenuation areas less than -950 Hounsfield units (%LAA-950; t = -4.387,P = 0), percentage of wall area (WA%; t = -4.501, P = 0), and thickness-diameter ratio (TDR; t = -4.779, P = 0) in the COPD group were higher than those in the normal group. ROC shows that: %LAA-950 (P = .047) and TDR (P = .034) were independent influence in COPD in the plateau. %LAA-950 combined with TDR (AUC = 0.757, P < .001) had the value of diagnosis of COPD in the plateau. All 3 indexes are negatively correlated with lung function, and positively correlated with the symptoms and the number of acute exacerbations. Multiple linear regression analysis showed that the main factors for decrease of ratio of measurement to prediction of forced expiratory volume to the first second (FEV1%) included %LAA-950 (OR = -0.449, P < .001) and WA% (OR = -0.516, P < .001). CT indexes have a certain diagnostic value in patients with stable COPD at high altitude.

PiSlope: A New CT Metric for Quantifying Airway Remodeling in Chronic Obstructive Pulmonary Disease

Background Airway wall thickening is commonly quantified at chest CT with Pi10, the square root of the wall area of a hypothetical airway with a luminal perimeter of 10 mm. Although Pi10 has proven to be a useful construct, it assumes uniform thickening of all airways and considers only a single airway level in summarizing airway remodeling, limiting its accuracy. Purpose To evaluate PiSlope, a new metric for the quantification of airway wall thickening. Materials and Methods In this secondary analysis of data from a multicenter prospective study of individuals who currently smoke or formerly smoked as well as healthy volunteers who never smoked enrolled from January 2008 to June 2011 and followed up longitudinally until September 2022, chest CT images were analyzed section by section to quantify the luminal perimeter and airway wall thickness for each visible airway. Linear regression was used to calculate the slope of the luminal perimeter against wall thickness to determine the PiSlope. PiSlope was normalized by the individual's height squared. Multivariable regression was used to test the associations between airway metrics and respiratory outcomes. Results The mean age of the 8199 participants was 59.5 years ± 9.1 (SD), with 53% male and 67% White participants. With increasing disease severity (ie, Global Initiative for Chronic Obstructive Lung Disease stages 0-4), Pi10 increased (4.26 mm ± 0.23, 4.29 mm ± 0.21, 4.43 mm ± 0.26, 4.51 mm ± 0.28, and 4.53 mm ± 0.27, respectively) and PiSlope decreased (0.38 ± 0.10, 0.38 ± 0.10, 0.35 ± 0.11, 0.33 ± 0.10, and 0.31 ± 0.10) (trend test; both P < .001). Multivariable analyses revealed that PiSlope was associated with dyspnea, respiratory quality of life, 6-minute walk distance, exacerbations, lung function decline, and all-cause mortality, with and without Pi10 being included in the model. Conclusion The new metric PiSlope quantifies airway wall remodeling and shows associations with respiratory symptoms, quality of life, exacerbations, lung function decline, and all-cause mortality. Clinical trial registration no. NCT00608764 © RSNA, 2024 See also the editorial by Lynch in this issue.

Effect of high-dose N-acetylcysteine on exacerbations and lung function in patients with mild-to-moderate COPD: a double-blind, parallel group, multicentre randomised clinical trial

Evidence for the treatment of patients with mild-to-moderate chronic obstructive pulmonary disease (COPD) is limited. The efficacy of N-acetylcysteine (an antioxidant and mucolytic agent) for patients with mild-to-moderate COPD is uncertain. In this multicentre, randomised, double-blind, placebo-controlled trial, we randomly assigned 968 patients with mild-to-moderate COPD to treatment with N-acetylcysteine (600 mg, twice daily) or matched placebo for two years. Eligible participants were 40-80 years of age and had mild-to-moderate COPD (forced expiratory volume in 1 second [FEV1] to forced vital capacity ratio <0.70 and an FEV1 ≥ 50% predicted value after bronchodilator use). The coprimary outcomes were the annual rate of total exacerbations and the between-group difference in the change from baseline to 24 months in FEV1 before bronchodilator use. COPD exacerbation was defined as the appearance or worsening of at least two major symptoms (cough, expectoration, purulent sputum, wheezing, or dyspnoea) persisting for at least 48 hours. Assessment of exacerbations was conducted every three months, and lung function was performed annually after enrolment. The difference between the N-acetylcysteine group and the placebo group in the annual rate of total exacerbation were not significant (0.65 vs. 0.72 per patient-year; relative risk [RR], 0.90; 95% confidence interval [CI], 0.80-1.02; P = 0.10). There was no significant difference in FEV1 before bronchodilator use at 24 months. Long-term treatment with high-dose N-acetylcysteine neither significantly reduced the annual rate of total exacerbations nor improved lung function in patients with mild-to-moderate COPD. Chinese Clinical Trial Registration: ChiCTR-IIR-17012604.

Design of the SPIROMICS Study of Early COPD Progression: SOURCE Study

Background

The biological mechanisms leading some tobacco-exposed individuals to develop early-stage chronic obstructive pulmonary disease (COPD) are poorly understood. This knowledge gap hampers development of disease-modifying agents for this prevalent condition.

Objectives

Accordingly, with National Heart, Lung and Blood Institute support, we initiated the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS) Study of Early COPD Progression (SOURCE), a multicenter observational cohort study of younger individuals with a history of cigarette smoking and thus at-risk for, or with, early-stage COPD. Our overall objectives are to identify those who will develop COPD earlier in life, characterize them thoroughly, and by contrasting them to those not developing COPD, define mechanisms of disease progression.

Methods/Discussion

SOURCE utilizes the established SPIROMICS clinical network. Its goal is to enroll n=649 participants, ages 30-55 years, all races/ethnicities, with ≥10 pack-years cigarette smoking, in either Global initiative for chronic Obstructive Lung Disease (GOLD) groups 0-2 or with preserved ratio-impaired spirometry; and an additional n=40 never-smoker controls. Participants undergo baseline and 3-year follow-up visits, each including high-resolution computed tomography, respiratory oscillometry and spirometry (pre- and postbronchodilator administration), exhaled breath condensate (baseline only), and extensive biospecimen collection, including sputum induction. Symptoms, interim health care utilization, and exacerbations are captured every 6 months via follow-up phone calls. An embedded bronchoscopy substudy involving n=100 participants (including all never-smokers) will allow collection of lower airway samples for genetic, epigenetic, genomic, immunological, microbiome, mucin analyses, and basal cell culture.

Conclusion

SOURCE should provide novel insights into the natural history of lung disease in younger individuals with a smoking history, and its biological basis.

The Impact of Heat-Not-Burn, E-Cigarettes, and Cigarettes on Small Airway Function

Introduction

E-cigarettes and heated tobacco products (HTPs) are gaining worldwide significance. The tobacco industry is promoting these products as healthier alternatives to conventional cigarettes.

Methods

In this four-arm crossover study, we examined the acute effects of cigarette smoking, vaping IQOS, or vaping e-cigarettes (with or without nicotine) on hemodynamics, arterial stiffness, and small airways. Twenty subjects (10 male, 10 female), all occasional smokers, completed each study arm. There was at least a 48 h washout period before each test day. Arterial stiffness and peripheral and central hemodynamics were assessed using Mobil-O-Graph™ (I.E.M., Germany), whereas tremoFlo® c-100 (Thoracic Medical Systems Inc) was used to evaluate the effects on the small airways and resistance.

Results

Cigarettes, IQOS, e-cigarettes containing nicotine, and nicotine-free e-cigarettes had similar effects on peripheral and central hemodynamics as well as on arterial stiffness. We observed a significant increase in all parameters. However, only nicotine-containing products lead to increased bronchial obstruction, higher reactance, and a higher tidal volume.

Conclusion

Therefore, we concluded that cigarettes, IQOS, and e-cigarettes have similar effects on hemodynamics. No differences were observed between the nicotine-containing and nicotine-free e-cigarettes. All nicotine-containing products also influence small airways. These findings suggest that e-cigarettes and HTPs are not healthier alternatives than conventional cigarettes.

An Italian Delphi Consensus on the Triple inhalation Therapy in Chronic Obstructive Pulmonary Disease

BACKGROUND

The management of chronic obstructive pulmonary disease (COPD) lacks standardization due to the diverse clinical presentation, comorbidities, and limited acceptance of recommended approaches by physicians. To address this, a multicenter study was conducted among Italian respiratory physicians to assess consensus on COPD management and pharmacological treatment.

METHODS

The study employed the Delphi process using the Estimate-Talk-Estimate method, involving a scientific board and expert panel. During a 6-month period, the scientific board conducted the first Delphi round and identified 11 broad areas of COPD management to be evaluated while the second Delphi round translated all 11 items into statements. The statements were subsequently presented to the expert panel for independent rating on a nine-point scale. Consensus was considered achieved if the median score was 7 or higher. Consistently high levels of consensus were observed in the first rating, allowing the scientific board to finalize the statements without requiring further rounds.

RESULTS

Topics generating substantial discussion included the pre-COPD phase, patient-reported outcomes, direct escalation from a single bronchodilator to triple therapy, and the role of adverse events, particularly pneumonia, in guiding triple therapy prescriptions. Notably, these topics exhibited higher standard deviations, indicating greater variation in expert opinions.

CONCLUSIONS

The study emphasized the significance that Italian pulmonologists attribute to managing mortality, tailoring treatments, and addressing cardiovascular comorbidities in COPD patients. While unanimous consensus was not achieved for all statements, the results provide valuable insights to inform clinical decision-making among physicians and contribute to a better understanding of COPD management practices in Italy.

It is high time to discard a cut-off of 0.70 in the diagnosis of COPD

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) has traditionally been diagnosed based on the criterion of an FEV1/FVC <0.70. However, this definition has limitations as it may only detect patients with later-stage disease, when pathologic changes have become irreversible. Consequently, it potentially omits individuals with early-stage disease, in whom the pathologic changes could be delayed or reversed.

AREAS COVERED

This narrative review summarizes recent evidence regarding early-stage COPD, which may not fulfill the spirometric criteria but nonetheless exhibits features of COPD or is at risk of future COPD progression.

EXPERT OPINION

A comprehensive approach, including symptoms assessment, various physiologic tests, and radiologic features, is required to diagnose COPD. This approach is necessary to identify currently underdiagnosed patients and to halt disease progression in at- risk patients.

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

BACKGROUND

A diagnosis of COPD is mainly considered in individuals with >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.

METHODS

We followed non-obstructed adult smokers from the Copenhagen City Heart Study for COPD, defined as a forced expiratory volume in 1 s (FEV1)/forced vital capacity <0.70 and FEV1 <80% predicted, and for related clinical outcomes. First, we followed individuals for 5 years according to baseline smoking for risk of developing COPD, and thereafter for up to four decades for severe exacerbations and death.

RESULTS

In 6098 non-obstructed smokers, 1781 (29%) developed COPD after 5 years of follow-up: 23% of individuals with <10 pack-years of smoking at baseline, 26% of those with 10-19.9 pack-years, 30% of those with 20-39.9 pack-years and 39% of those with ≥40 pack-years. During four decades of follow-up, we recorded 620 exacerbations and 5573 deaths. Compared to individuals without COPD with <10 pack‑years of smoking, multivariable adjusted hazard ratios (HRs) for exacerbations were 1.94 (95% CI 1.36-2.76) in those without COPD and ≥10 pack-years, 2.83 (95% CI 1.72-4.66) in those with COPD and <10 pack-years, 4.34 (95% CI 2.93-6.43) in those with COPD and 10-19.9 pack-years, 4.39 (95% CI 2.98-6.46) in those with COPD and 20-39.9 pack-years and 4.98 (95% CI 3.11-7.97) in those with COPD and ≥40 pack-years. Corresponding HRs for all-cause mortality were 1.20 (95% CI 1.10-1.32), 1.31 (95% CI 1.13-1.53), 1.59 (95% CI 1.40-1.79), 1.81 (95% CI 1.62-2.03) and 1.81 (95% CI 1.55-2.10).

CONCLUSION

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.

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.

Small airway dysfunction links asthma exacerbations with asthma control and health-related quality of life

BACKGROUND

Small airway dysfunction not only affects asthma control, but also has adverse effects on the psychological and/or social activities of asthma patients. However, few long-term observational studies have explored the complex relationship between small airway dysfunction and asthma control and health-related quality of life in patients with asthma exacerbations.

METHODS

The study recruited 223 patients with exacerbations of asthma (i.e. those with at least one asthma attack over the past year) and 228 patients without exacerbations of asthma (i.e. those without asthma attacks over the past year). We evaluated SAD in patients with asthma exacerbations using impulse oscillometry method. At each evaluation time point within one year of follow-up, the attending physician conducts a case investigation of the patients. We analyzed the correlation between SAD and general characteristics (age, obesity, smoking history), type 2 inflammation (blood eosinophils, exhaled nitric oxide), FEV1, as well as asthma control (ACT) and health-related quality of life (mini-AQLQ) in patients with asthma exacerbations, and constructed a structural equation model to evaluate the causality of these clinical variables.

RESULTS

The SAD prevalence in patients with asthma exacerbation is as high as 75%. SAD is connected with poor asthma control and poor health-related quality of life. The structural equation model indicates that age, obesity, FeNO, and FEV1 are independent predictive factors of SAD. SAD is the main determinant factor of asthma control, which in turn affected health-related quality of life. FEV1 and age directly affect asthma control and affect health-related quality of life through asthma control. In addition, there is a bidirectional relationship between FEV1 and small airway dysfunction and between asthma control and health-related quality of life.

CONCLUSIONS

Small airways are involved from an early stage in asthma. Abnormal function of the small airways can significantly increase airway resistance in asthma patients, while worsening their clinical symptoms. In addition, aging is also a key risk factor for asthma control. Especially, small airway dysfunction links asthma control with health-related quality of life.

Revealing the significance of early detection of chronic obstructive pulmonary disease: insights from healthy lung initiative data at COP27 conference

BACKGROUND

Climate change poses a significant threat to respiratory health, exacerbating conditions like asthma, Chronic Obstructive Pulmonary Disease (COPD), and respiratory infections increasing morbidity and mortality indirectly through exposure to greenhouse gases. During the 27th Climate Change Conference (COP27), the Healthy Lung Initiative (HLI) for the early detection of COPD among smokers was launched in Egypt.

OBJECTIVE

We aimed to detect the prevalence and predictors of confirmed COPD among smokers and assess physicians' adherence to prescribing pulmonary function tests (PFTs) among the COP27 conference attendees.

METHODS

This study utilized smokers' data from the HLI, employing a cross-sectional design with an interview-based questionnaire, supplemented by spirometry for lung function evaluation. Participants, comprising Egyptian and non-Egyptian residents in Sharm El-Sheikh city, were provided with educational materials and encouraged to seek further evaluation from a pulmonologist.

RESULTS

The HLI study, conducted from November 6th to 20th, 2022, involved 1133 participants, 90% (1047) of whom were smokers. Most smokers were males (96.3%) and Egyptians (98.6%), with half aged 30-39 and the majority starting smoking within the last 20 years. Despite common respiratory symptoms, 47% suffered from dyspnea on exertion, and only 4.3% have undergone lung function tests, suggesting a potential underdiagnosis of COPD. Most participants (82.6%) had an FEV1/FVC ratio > 70%, indicating no spirometry-confirmed COPD diagnosis, while 147 participants (17% of them) exhibited all three cardinal COPD symptoms simultaneously. Male gender and daily cigarette consumption were significant predictors for confirmed COPD, while age showed no significance in regression analyses.

CONCLUSION

The ongoing HLI focuses on early detection and education to combat smoking-related risks, particularly among middle-aged males, while also highlighting the need for comprehensive strategies to address the intersection of smoking and climate change.

Machine learning for accurate detection of small airway dysfunction-related respiratory changes: an observational study

BACKGROUND

The use of machine learning(ML) methods would improve the diagnosis of small airway dysfunction(SAD) in subjects with chronic respiratory symptoms and preserved pulmonary function(PPF). This paper evaluated the performance of several ML algorithms associated with the impulse oscillometry(IOS) analysis to aid in the diagnostic of respiratory changes in SAD. We also find out the best configuration for this task.

METHODS

IOS and spirometry were measured in 280 subjects, including a healthy control group (n = 78), a group with normal spirometry (n = 158) and a group with abnormal spirometry (n = 44). Various supervised machine learning (ML) algorithms and feature selection strategies were examined, such as Support Vector Machines (SVM), Random Forests (RF), Adaptive Boosting (ADABOOST), Navie Bayesian (BAYES), and K-Nearest Neighbors (KNN).

RESULTS

The first experiment of this study demonstrated that the best oscillometric parameter (BOP) was R5, with an AUC value of 0.642, when comparing a healthy control group(CG) with patients in the group without lung volume-defined SAD(PPFN). The AUC value of BOP in the control group was 0.769 compared with patients with spirometry defined SAD(PPFA) in the PPF population. In the second experiment, the ML technique was used. In CGvsPPFN, RF and ADABOOST had the best diagnostic results (AUC = 0.914, 0.915), with significantly higher accuracy compared to BOP (p < 0.01). In CGvsPPFA, RF and ADABOOST had the best diagnostic results (AUC = 0.951, 0.971) and significantly higher diagnostic accuracy (p < 0.01). In the third, fourth and fifth experiments, different feature selection techniques allowed us to find the best IOS parameters (R5, (R5-R20)/R5 and Fres). The results demonstrate that the performance of ADABOOST remained essentially unaltered following the application of the feature selector, whereas the diagnostic accuracy of the remaining four classifiers (RF, SVM, BAYES, and KNN) is marginally enhanced.

CONCLUSIONS

IOS combined with ML algorithms provide a new method for diagnosing SAD in subjects with chronic respiratory symptoms and PPF. The present study's findings provide evidence that this combination may help in the early diagnosis of respiratory changes in these patients.

Analysis of the relationship between comorbid obstructive sleep apnea and clinical outcomes in patients with asthma in Japan

BACKGROUND

Asthma and obstructive sleep apnea (OSA) are prevalent chronic respiratory disorders, which often coexist and interact with each other. Obesity is an important risk factor shared by them. The rate of obesity is lower in Japan versus Western countries. Hence, the co-existence of asthma and OSA has not been investigated in Japan.

METHODS

Ninety-seven outpatients with asthma were recruited. Patients wore a portable monitor for sleep study. Background data, pulmonary function, blood tests, and patient-reported outcomes including gastroesophageal reflux disease, sleepiness, sleep quality, asthma control, cough and respiratory symptoms, and health status, were assessed.

RESULTS

Of the patients, 19 (19.6 %), 40 (41.2 %), 24 (24.7 %), and 14 (14.4 %) were classified into non-, mild, moderate, and severe OSA groups. Non-OSA patients were younger than those in other groups (p < 0.05). The BMI of patients with moderate and severe OSA, was higher than that of non-OSA patients (p < 0.05). Pulmonary function, FeNO, serum IgE, and the number of peripheral eosinophils were not significantly different between groups. Nonetheless, compared with the other groups, treatment step was the highest, and the Asthma Control Test, Leicester Cough Questionnaire, COPD Assessment Test, and Asthma Health Questionnaire-33 yielded worst scores in the severe OSA group, and predicted the severe OSA after adjustment by BMI.

CONCLUSIONS

Moderate and severe OSA are highly prevalent among patients with asthma in Japan. Pulmonary function did not differ between groups. However, patients with asthma and severe OSA were linked to more asthma treatment, worse asthma control, more symptoms and cough, and worse health status.

Treatable traits in pre-COPD: Time to extend the treatable traits paradigm beyond established disease

To date, the treatable traits (TTs) approach has been applied in the context of managing diagnosed diseases. TTs are clinical characteristics and risk factors that can be identified clinically and/or biologically, and that merit treatment if present. There has been an exponential increase in the uptake of this approach by both researchers and clinicians. Realizing the potential of the TTs approach to pre-clinical disease, this expert review proposes that it is timely to consider acting on TTs present before a clinical diagnosis is made, which might help to prevent development of the full disease. Such an approach is ideal for diseases where there is a long pre-clinical phase, such as in chronic obstructive pulmonary disease (COPD). The term 'pre-COPD' has been recently proposed to identify patients with respiratory symptoms and/or structural or functional abnormalities without airflow limitation. They may eventually develop airflow limitation with time but patients with pre-COPD are likely to have traits that are already treatable. This review first outlines the contribution of recently generated knowledge into lifetime lung function trajectories and the conceptual framework of 'GETomics' to the field of pre-COPD. GETomics is a dynamic and cumulative model of interactions between genes and the environment throughout the lifetime that integrates information from multi-omics to understand aetiology and mechanisms of diseases. This review then discusses the current evidence on potential TTs in pre-COPD patients and makes recommendations for practice and future research. At a broader level, this review proposes that introducing the TTs in pre-COPD may help reenergize the preventive approaches to health and diseases.

What is pre-COPD and do we know how to treat it?

INTRODUCTION

Chronic Obstructive Pulmonary Disease (COPD) is one of the leading causes of morbidity and mortality worldwide. The lung damage in COPD is associated with an enhanced chronic inflammatory response in the airways and lung tissue to harmful particles or gases. Early detection and treatment of COPD can help manage symptoms and slow the progression of the disease.

AREAS COVERED

Status of knowledge regarding early diagnosis, definition of pre-COPD, possible new tools for early diagnosis, possibilities of early treatment, and the results of studies in this population are discussed. Literature search (2014-2024) was done in PubMed, EMBASE, and WoS databases using the keywords COPD, early diagnosis, treatment, smoking, prevention; with additional search of literature in found articles.

EXPERT OPINION

No early case-finding programs have been proposed or validated, so we still have many patients diagnosed in the late stage of the disease. Clinically manifest COPD is characterized as typically progressive and irreversible with current therapeutic options. If we aim to reduce the mortality and morbidity from COPD we should target these steps: Prevention; Early diagnosis; Form registries of persons at risk for COPD development; Diagnose preclinical COPD; and discover new preventive therapeutic interventions.

Airway Mucus Plugs in Community-Living Adults: A Study Protocol

Introduction

Mucus pathology plays a critical role in airway diseases like Chronic Bronchitis (CB) and Chronic Obstructive Pulmonary Disease (COPD). Up to 32% of community-living persons report clinical manifestations of mucus pathology (e.g., cough and sputum production). However, airway mucus pathology has not been systematically studied in community-living individuals. In this study, we will use an objective, reproducible assessment of mucus pathology on chest Computed Tomography (CT) scans from community-living individuals participating in the Coronary Artery Risk Development in Young Adults (CARDIA) and Framingham Heart Study (FHS) cohorts.

Methods and analysis

We will determine the clinical relevance of CT-based mucus plugs and modifiable and genetic risk and protective factors associated with this process. We will evaluate the associations of mucus plugs with lung function, respiratory symptoms, and chronic bronchitis and examine whether 5-yr. persistent CT-based mucus plugs are associated with the decline in FEV1 and future COPD. Also, we will assess whether modifiable factors, including air pollution and marijuana smoking are associated with increased odds of CT-based mucus plugs and whether cardiorespiratory fitness is related in an opposing manner. Finally, we will determine genetic resilience/susceptibility to mucus pathology. We will use CT data from the FHS and CARDIA cohorts and genome-wide sequencing data from the TOPMed initiative to identify common and rare variants associated with CT-based mucus plugging.

Ethics and dissemination

The Mass General Brigham Institutional Review Board approved the study. Findings will be disseminated through peer-reviewed journals and at professional conferences.

Conclusion

Determine whether the presence of CT-based mucus plugs is associated with lung health impairment, including reduced FEV1, more respiratory symptoms, and asthma. Identify modifiable risk and protective factors, such as pollution, exercise, smoking, and fitness that are associated with mucus plugs.

Airway Mucus Plugs in Community-Living Adults: A Study Protocol

Introduction

Mucus pathology plays a critical role in airway diseases like chronic bronchitis (CB) and chronic obstructive pulmonary disease (COPD). Up to 32% of community-living persons report clinical manifestations of mucus pathology (e.g., cough and sputum production). However, airway mucus pathology has not been systematically studied in community-living individuals. In this study, we will use an objective, reproducible assessment of mucus pathology on chest computed tomography (CT) scans from community-living individuals participating in the Coronary Artery Risk Development in Young Adults (CARDIA) and Framingham Heart Study (FHS) cohorts.

Methods and analysis

We will determine the clinical relevance of CT-based mucus plugs and modifiable and genetic risk and protective factors associated with this process. We will evaluate the associations of mucus plugs with lung function, respiratory symptoms, and chronic bronchitis and examine whether 5-yr. persistent CT-based mucus plugs are associated with the decline in FEV1 and future COPD. Also, we will assess whether modifiable factors, including air pollution and marijuana smoking are associated with increased odds of CT-based mucus plugs and whether cardiorespiratory fitness is related in an opposing manner. Finally, we will determine genetic resilience/susceptibility to mucus pathology. We will use CT data from the FHS and CARDIA cohorts and genome-wide sequencing data from the TOPMed initiative to identify common and rare variants associated with CT-based mucus plugging.

Ethics and Dissemination

The Mass General Brigham Institutional Review Board approved the study. Findings will be disseminated through peer-reviewed journals and at professional conferences.

Risk of Chronic Obstructive Pulmonary Disease and Receipt of a Breathing Test in 26 States and the District of Columbia, 2017-2018

We estimated the prevalence of respiratory symptoms, chronic obstructive pulmonary disease (COPD) risk level, and receipt of a breathing test among adults without reported COPD in 26 states and the District of Columbia by using 2017-2018 Behavioral Risk Factor Surveillance System data. Among adults without reported COPD, the 3 respiratory symptoms indicating COPD (chronic cough, phlegm or mucus production, shortness of breath) were common (each >10%). About 15.0% were at higher COPD risk (based on the number of symptoms, age, and smoking status); 41.4% of adults at higher risk reported receipt of a breathing test. Patient-provider recognition and communication of risk symptoms, appropriate screening, and follow-up are important for early diagnosis and treatment.

N-acetylcysteine Treatment in Chronic Obstructive Pulmonary Disease (COPD) and Chronic Bronchitis/Pre-COPD: Distinct Meta-analyses

INTRODUCTION

N-acetylcysteine (NAC) is a mucolytic agent with antioxidant properties. Oxidative stress is a key pathogenic mechanism in chronic respiratory conditions such as COPD and chronic bronchitis (CB). In these meta-analyses we investigated the efficacy of NAC in subjects with COPD or CB, the latter being a potential pre-COPD condition (CB/pre-COPD).

METHODS

The meta-analyses were conducted according to PRISMA guidelines. Exacerbations were assessed using total number of exacerbations. Improvement in patients' respiratory symptoms and/or patients quality of life (QoL) were measured by validated tools or assessed at the end of the study.

RESULTS

Twenty studies were included, of which seven evaluated NAC in patients with symptoms of CB/pre-COPD as entry criterion. NAC treated patients showed a significant reduction of the incidence of exacerbations as compared to placebo both in COPD (IRR=0.76; 95% confidence interval (CI) 0.59-0.99) and CB/pre-COPD (IRR=0.81; 95% CI 0.69-0.95). Sensitivity analyses in studies with duration higher than 5 months, confirmed the overall results. CB/pre-COPD patients treated with NAC were significantly more likely to experience an improvement in symptoms and/or QoL compared to placebo (odds ratio (OR)=3.47; 95% CI 1.92-6.26). A similar trend was observed in the few COPD studies evaluable. Sensitivity analyses showed a significant association of NAC with improvement in symptoms and/or QoL both in CB/pre-COPD and COPD patients.

CONCLUSIONS

These findings provide novel data of NAC on the improvement in symptoms and QoL in addition to prevention of exacerbations in COPD and CB/pre-COPD. PROSPERO registry no. CRD42023468154.

Respiratory symptoms and outcomes among cigar smokers: findings from the Population Assessment of Tobacco and Health (PATH) study waves 2-5 (2014-2019)

BACKGROUND

The mechanisms by which cigarette smoking increases the risk of respiratory disease have been studied. However, less is known about risks of respiratory symptoms and outcomes associated with smoking cigars, and risks by cigar types have not been previously explored. The aim of this study was to examine associations between cigar use, including traditional cigars, cigarillos, filtered cigars, and dual cigar and cigarette use, and functionally important respiratory symptoms (FIRS), lifetime asthma diagnosis, uncontrolled asthma, and new cases of FIRS.

METHODS

Data from Waves 2-5 (2014-19) of the Population Assessment of Tobacco and Health (PATH) Study, a nationally representative longitudinal study, were analyzed in two ways. For cross-sectional analysis, the analytic sample included adults 18 and older at each wave, resulting in 44,040 observations. Separately, longitudinal analyses were assessed among adults 18 and older at Wave 2, resulting in 7,930 individuals. Both analyses excluded adults with chronic obstructive pulmonary disease (COPD) or non-asthma respiratory disease.

RESULTS

Current established cigarillo smokers had higher odds of having FIRS (Adjusted odds ratio (AOR): 1.72; 95% CI: 1.08, 2.74) compared to never smokers of cigarillos and cigarettes, after adjusting for covariates. Current established filtered cigar smokers had higher odds of asthma diagnosis (AOR: 1.35; 95% CI: 1.10, 1.66) while current established dual smokers of filtered cigars and cigarettes had higher odds of uncontrolled asthma (AOR: 5.13; 95% CI: 1.75, 15.02) compared to never smokers of filtered cigars or cigarettes. Both current established cigar smokers and current established dual smokers of cigarettes and cigars had higher odds of new FIRS compared to never cigar or cigarette smokers (AORs: 1.62; 95% CI: 1.02, 2.60 for exclusive cigars and 2.55; 95% CI 1.57, 4.14 for dual smokers).

CONCLUSIONS

This study provides evidence that cigar smokers or dual smokers of cigars and cigarettes have greater odds of FIRS, asthma, and uncontrolled asthma and that new incidence of FIRS is higher among any cigar smokers compared to never cigar or cigarette smokers. Understanding health impacts associated with cigar use provides information for supporting policy development, as well as for designing clinical interventions focused on smoking cessation for cigars.