Effects of smoking and smoking cessation on longitudinal decline in pulmonary function

Novel DNA methylation changes in mouse lungs associated with chronic smoking

Smoking is a potent cause of asthma exacerbations, chronic obstructive pulmonary disease (COPD) and many other health defects, and changes in DNA methylation (DNAm) have been identified as a potential link between smoking and these health outcomes. However, most studies of smoking and DNAm have been done using blood and other easily accessible tissues in humans, while evidence from more directly affected tissues such as the lungs is lacking. Here, we identified DNAm patterns in the lungs that are altered by smoking. We used an established mouse model to measure the effects of chronic smoke exposure first on lung phenotype immediately after smoking and then after a period of smoking cessation. Next, we determined whether our mouse model recapitulates previous DNAm patterns observed in smoking humans, specifically measuring DNAm at a candidate gene responsive to cigarette smoke, Cyp1a1. Finally, we carried out epigenome-wide DNAm analyses using the newly released Illumina mouse methylation microarrays. Our results recapitulate some of the phenotypes and DNAm patterns observed in human studies but reveal 32 differentially methylated genes specific to the lungs which have not been previously associated with smoking. The affected genes are associated with nicotine dependency, tumorigenesis and metastasis, immune cell dysfunction, lung function decline, and COPD. This research emphasizes the need to study CS-mediated DNAm signatures in directly affected tissues like the lungs, to fully understand mechanisms underlying CS-mediated health outcomes.

Association between n-3 PUFA and lung function: results from the NHANES 2007-2012 and Mendelian randomisation study

This study aimed to investigate the association between n-3 PUFA and lung function. First, a cross-sectional study was conducted based on the National Health and Nutrition Examination Survey (NHANES) 2007-2012 data. n-3 PUFA intake was obtained from 24-h dietary recalls. A multivariable linear regression model was used to assess the observational associations of n-3 PUFA intake with lung function. Subsequently, a two-sample Mendelian randomisation (MR) was performed to estimate the potential causal effect of n-3 PUFA on lung function. Genetic instrumental variables were extracted from published genome-wide association studies. Summary statistics about n-3 PUFA was from UK Biobank. Inverse variance weighted was the primary analysis approach. The observational study did not demonstrate a significant association between n-3 PUFA intake and most lung function measures; however, a notable exception was observed with significant findings in the highest quartile for forced vital capacity (FVC) and % predicted FVC. The MR results also showed no causal effect of circulating n-3 PUFA concentration on lung function (forced expiratory volume in one second (FEV1), β = 0·01301, se = 0·01932, P = 0·5006; FVC, β = -0·001894, se = 0·01704, P = 0·9115; FEV1:FVC, β = 0·03118, se = 0·01743, P = 0·07359). These findings indicate the need for further investigation into the impact of higher n-3 PUFA consumption on lung health.

Determinants of recovery from post-COVID-19 dyspnoea: analysis of UK prospective cohorts of hospitalised COVID-19 patients and community-based controls

Background

The risk factors for recovery from COVID-19 dyspnoea are poorly understood. We investigated determinants of recovery from dyspnoea in adults with COVID-19 and compared these to determinants of recovery from non-COVID-19 dyspnoea.

Methods

We used data from two prospective cohort studies: PHOSP-COVID (patients hospitalised between March 2020 and April 2021 with COVID-19) and COVIDENCE UK (community cohort studied over the same time period). PHOSP-COVID data were collected during hospitalisation and at 5-month and 1-year follow-up visits. COVIDENCE UK data were obtained through baseline and monthly online questionnaires. Dyspnoea was measured in both cohorts with the Medical Research Council Dyspnoea Scale. We used multivariable logistic regression to identify determinants associated with a reduction in dyspnoea between 5-month and 1-year follow-up.

Findings

We included 990 PHOSP-COVID and 3309 COVIDENCE UK participants. We observed higher odds of improvement between 5-month and 1-year follow-up among PHOSP-COVID participants who were younger (odds ratio 1.02 per year, 95% CI 1.01-1.03), male (1.54, 1.16-2.04), neither obese nor severely obese (1.82, 1.06-3.13 and 4.19, 2.14-8.19, respectively), had no pre-existing anxiety or depression (1.56, 1.09-2.22) or cardiovascular disease (1.33, 1.00-1.79), and shorter hospital admission (1.01 per day, 1.00-1.02). Similar associations were found in those recovering from non-COVID-19 dyspnoea, excluding age (and length of hospital admission).

Interpretation

Factors associated with dyspnoea recovery at 1-year post-discharge among patients hospitalised with COVID-19 were similar to those among community controls without COVID-19.

Funding

PHOSP-COVID is supported by a grant from the MRC-UK Research and Innovation and the Department of Health and Social Care through the National Institute for Health Research (NIHR) rapid response panel to tackle COVID-19. The views expressed in the publication are those of the author(s) and not necessarily those of the National Health Service (NHS), the NIHR or the Department of Health and Social Care.COVIDENCE UK is supported by the UK Research and Innovation, the National Institute for Health Research, and Barts Charity. The views expressed are those of the authors and not necessarily those of the funders.

Health impact of e-cigarettes and heated tobacco products in chronic obstructive pulmonary disease: current and emerging evidence

INTRODUCTION

Quitting is the only proven method to attenuate the progression of chronic obstructive pulmonary disease (COPD). However, most COPD smokers do not seem to respond to smoking cessation interventions and may benefit by lessening the negative health effects of long-term cigarette smoke exposure by switching to non-combustible nicotine delivery alternatives, such as heated tobacco products (HTPs) and e-cigarettes (ECs).

AREAS COVERED

Compared with conventional cigarettes, HTPs and ECs offer substantial reduction in exposure to toxic chemicals and have the potential to reduce harm from cigarette smoke when used as tobacco cigarette substitutes. In this review, we examine the available clinical studies and population surveys on the respiratory health effects of ECs and HTPs in COPD patients.

EXPERT OPINION

The current research on the impact of ECs and HTPs on COPD patients' health is limited, and more high-quality studies are needed to draw definitive conclusions. However, this review provides a comprehensive overview of the available literature for health professionals looking to advise COPD patients on the use of these products. While ECs and HTPs may offer some benefits in reducing harm from cigarette smoke, their long-term effects on COPD patients' health are still unclear.

Risk assessment and dose-effect of co-exposure to benzene, toluene, ethylbenzene, xylene, and styrene (BTEXS) on pulmonary function: A cross-sectional study

Inhalation is the most frequent route and the lung is the primary damaged organ for human exposure to benzene, toluene, ethylbenzene, xylene, and styrene (BTEXS). However, there is limited information on the risk and dose-effect of the BTEXS mixture on pulmonary function, particularly the overall effect. We conducted a cross-sectional study in a petrochemical plant in southern China. Spirometry and cumulative exposure dose (CED) of BTEXS were used to measure lung function and exposure levels for 635 workers in 2020, respectively. Forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV₁) were tested and interpreted as percentages to predicted values [FVC or FEV₁% predicted], and FEV₁ to FVC ratio [FEV₁/FVC (%)]. We found the reduction in FVC% predicted and the risk of lung ventilation dysfunction (LVD) and its two subtypes (mixed and restrictive ventilation dysfunction, MVD, and MVD) were significantly associated with BTEXS individuals. In addition, pulmonary function damage associated with BTEXS was modified by the smoking status and age. Generalized weighted quantile sum (gWQS) regressions were used to estimate the overall dose-effect on lung function damage induced by the BTEXS mixture. Our results show wqs, an index of weighted quartiles for BTEXS, was potentially associated with the reduction in FVC and FEV₁% predicted with the coefficients [95% confidence intervals (CI)] between -1.136 (-2.202, -0.070) and -1.230 (-2.265, -0.195). Odds ratios (ORs) and 95% CIs for the wqs index of LVD, MVD, and RVD were 1.362 (1.129, 1.594), 1.323 (1.084, 1.562), and 1.394 (1.096, 1.692), respectively. Furthermore, xylene, benzene, and toluene in the BTEXS mixture potentially contribute to the development of lung function impairment. Our novel findings demonstrated the dose-response relationships between pulmonary function impairment and the BTEXS mixture and disclosed the potential key pollutants in the BTEXS mixture.

The Role of Smoking and Body Mass Index in Mortality Risk Assessment for Geriatric Hip Fracture Patients

Background

Smoking, obesity, and being below a healthy body weight are known to increase all-cause mortality rates and are considered modifiable risk factors. The purpose of this study is to assess whether adding these risk factors to a validated geriatric inpatient mortality risk tool will improve the predictive capacity for hip fracture patients. We hypothesize that the predictive capacity of the Score for Trauma Triage in the Geriatric and Middle-Aged (STTGMA) tool will improve.

Methodology

Between October 2014 and August 2021, 2,421 patients >55-years-old treated for hip fractures caused by low-energy mechanisms were analyzed for demographics, injury details, hospital quality measures, and mortality. Smoking status was recorded as a current every-day smoker, former smoker, or never smoker. Smokers (current and former) were compared to non-smokers (never smokers). Body mass index (BMI) was defined as underweight (<18.5 kg/m²), healthy weight (18.5-24.9 kg/m²), overweight (25.0-24.9 kg/m²), or obese (>30 kg/m²). The baseline STTGMA tool for hip fractures (STTGMAHIP_FX_SCORE) was modified to include patients’ BMI and smoking status (STTGMA_MODIFIABLE), and new mortality risk scores were calculated. Each model’s predictive ability was compared using DeLong’s test by analyzing the area under the receiver operating curves (AUROCs). Comparative analyses were conducted on each risk quartile.

Results

A comparison of smokers versus non-smokers demonstrated that smokers experienced higher rates of inpatient (p = 0.025) and 30-day (p = 0.048) mortality, myocardial infarction (p < 0.01), acute respiratory failure (p < 0.01), and a longer length of stay (p = 0.014). Comparison among BMI cohorts demonstrated that underweight patients experienced higher rates of pneumonia (p = 0.033), decubitus ulcers (p = 0.046), and the need for an intensive care unit (ICU) (p < 0.01). AUROC comparison demonstrated that STTGMA_MODIFIABLE significantly improved the predictive capacity for inpatient mortality compared to STTGMAHIP_FX_SCORE (0.792 vs. 0.672, p = 0.0445). Quartile stratification demonstrated the highest risk cohort had a longer length of stay (p < 0.01), higher rates of inpatient (p < 0.01) and 30-day mortality (p < 0.01), and need for an ICU (p < 0.01) compared to the minimal risk cohort. Patients in the lowest risk quartile were most likely to be discharged home (p < 0.01).

Conclusions

Smoking, obesity, and being below a healthy body weight increase the risk of perioperative complications and poor outcomes. Including smoking and BMI improves the STTGMAHIP_FX_SCORE tool to predict mortality and risk stratify patient outcomes. Because smoking, obesity, and being below a healthy body weight are modifiable patient factors, providers can counsel patients and implement lifestyle changes to potentially decrease their risk of longer-term poor outcomes, especially in the setting of another fracture. For patients who are former smokers, providers can use this information to encourage continued restraint and healthy choices.

Pulmonary function is associated with cognitive decline and structural brain differences

The association of poor pulmonary function (PF) with cognitive trajectories and structural brain differences remains unclear. Within the Rush Memory and Aging Project, 1377 dementia-free subjects were followed up to 21 years. PF was assessed with a composite score measured at baseline. Global and domain-specific cognitive function was assessed annually constructed from 19 cognitive tests. A subsample of 351 participants underwent brain magnetic resonance imaging to investigate the cross-sectional association between PF and structural brain volumes. We found that low PF was related to faster decline in global cognition, and domain-specific function including episodic memory, semantic memory, working memory, visuospatial ability, and perceptual speed. In addition, low PF was associated with smaller volumes of total brain, white matter and gray matter, and larger white matter hyperintensities volume. Our results suggest that low PF is associated with faster cognitive decline, and both neurodegeneration and vascular brain lesions may underlie the association.

Association between smoking cessation and alterations in forced expiratory volume in one second (FEV1). A Follow-Up Study from a Greek Tobacco Cessation Clinic

Background

Cigarette smoking is the most important preventable cause of several diseases such as malignancies, pulmonary and cardiovascular diseases. Smoking cessation is now supported by both behavioral counseling and medical pharmacotherapy and is the only effective approach for slowing down an accelerated decline in forced expiratory volume in one second (FEV1). Our study aims to examine changes in forced expiratory volume in one second (FEV1) after smoking cessation for smokers attending our smoking cessation clinic their correlation to smokers' demographic characteristics.

Methods

114 smokers (48 males and 66 females), with a mean age of 48.36±10.49 years, were enrolled. They were classified in 4 groups, according to their age; <40 years (Group Α), 41-50 years (Group Β), 51-60 years (Group C), >60 years (Group D) and underwent Spirometry on the 1st day of visit, one month (2nd visit) and, 3 months later (3rd visit).

Findings

Statistically significant increase in FEV1 values at the 2^nd and 3^rd visit compared to the 1^st visit was observed in smokers who quit smoking in Group Α, B and C (p<0.05). In addition, a statistically significant decrease in FEV1 values at the 2^nd and 3^rd visit compared to the 1^st visit was noticed in smokers who continued smoking in Group B, C and D (p<0.05).

Conclusion

Smoking cessation achieved through smoking cessation support led to the improvement of FEV1 values within 3 months. The greatest benefit was observed in smokers under the age of 60.

Airborne Occupational Exposures and Lung Function in the Lifelines Cohort Study

Rationale: The association between airborne occupational exposures and lung function level is inconsistent in the general population. Moreover, little is known about the association between occupational exposures and annual lung function decline.Objectives: We investigated the association between occupational exposures and lung function level and annual lung function decline in the population-based Lifelines cohort study.Methods: We included 55,631 adults with baseline spirometry and reliable job code-13,759 of these subjects were aged ≥30 years and underwent spirometry again after 4.5 years of follow-up. Occupational exposures in the current or last-held job at baseline were estimated with the ALOHA+ job-exposure matrix. Linear regression analyses adjusted for covariates were used to test the association between each occupational exposure-biological dust, mineral dust, gases and fumes, pesticides, solvents, and metals-and lung function level and annual lung function decline. Interactions were used to test effect modification by sex or smoking.Results: Exposures to biological dust, mineral dust, gases and fumes, insecticides, fungicides, and aromatic solvents were associated with a lower lung function level at baseline. The effects were larger in males and smokers compared with females and nonsmokers, respectively. However, no association between occupational exposures and the rate of annual lung function decline was found between baseline and follow-up.Conclusions: In this study, airborne occupational exposures are associated with lower lung function level but not with a faster lung function decline. These negative effects are more pronounced among males and smokers.

ACO (Asthma-COPD Overlap) Is Independent from COPD: The Case in Favour

Over the last decade interest has been shown in people with symptomatic lung disease who have features both of COPD and asthma. In this review we examine how COPD and asthma are defined and examine clinical characteristics of people defined by researchers as having asthma-COPD overlap (ACO). We look at pathological and physiological features along with symptoms and consider the impact of each diagnosis upon therapeutic management. We highlight challenges in the diagnosis and management of airway disease and the various phenotypes that could be part of ACO, in so doing suggesting ways for the clinician to manage patients with features of both asthma and COPD.

Fourteen days of smoking cessation improves muscle fatigue resistance and reverses markers of systemic inflammation

Cigarette smoking has a negative effect on respiratory and skeletal muscle function and is a risk factor for various chronic diseases. To assess the effects of 14 days of smoking cessation on respiratory and skeletal muscle function, markers of inflammation and oxidative stress in humans. Spirometry, skeletal muscle function, circulating carboxyhaemoglobin levels, advanced glycation end products (AGEs), markers of oxidative stress and serum cytokines were measured in 38 non-smokers, and in 48 cigarette smokers at baseline and after 14 days of smoking cessation. Peak expiratory flow (p = 0.004) and forced expiratory volume in 1 s/forced vital capacity (p = 0.037) were lower in smokers compared to non-smokers but did not change significantly after smoking cessation. Smoking cessation increased skeletal muscle fatigue resistance (p < 0.001). Haemoglobin content, haematocrit, carboxyhaemoglobin, total AGEs, malondialdehyde, TNF-α, IL-2, IL-4, IL-6 and IL-10 (p < 0.05) levels were higher, and total antioxidant status (TAS), IL-12p70 and eosinophil numbers were lower (p < 0.05) in smokers. IL-4, IL-6, IL-10 and IL-12p70 had returned towards levels seen in non-smokers after 14 days smoking cessation (p < 0.05), and IL-2 and TNF-α showed a similar pattern but had not yet fully returned to levels seen in non-smokers. Haemoglobin, haematocrit, eosinophil count, AGEs, MDA and TAS did not significantly change with smoking cessation. Two weeks of smoking cessation was accompanied with an improved muscle fatigue resistance and a reduction in low-grade systemic inflammation in smokers.

Interaction between Genetic Risk Scores for reduced pulmonary function and smoking, asthma and endotoxin

Rationale

Genome-wide association studies (GWASs) have identified numerous loci associated with lower pulmonary function. Pulmonary function is strongly related to smoking and has also been associated with asthma and dust endotoxin. At the individual SNP level, genome-wide analyses of pulmonary function have not identified appreciable evidence for gene by environment interactions. Genetic Risk Scores (GRSs) may enhance power to identify gene–environment interactions, but studies are few.

Methods

We analysed 2844 individuals of European ancestry with 1000 Genomes imputed GWAS data from a case–control study of adult asthma nested within a US agricultural cohort. Pulmonary function traits were FEV₁, FVC and FEV₁/FVC. Using data from a recent large meta-analysis of GWAS, we constructed a weighted GRS for each trait by combining the top (p value<5×10⁻⁹) genetic variants, after clumping based on distance (±250 kb) and linkage disequilibrium (r²=0.5). We used linear regression, adjusting for relevant covariates, to estimate associations of each trait with its GRS and to assess interactions.

Results

Each trait was highly significantly associated with its GRS (all three p values<8.9×10⁻⁸). The inverse association of the GRS with FEV₁/FVC was stronger for current smokers (p_interaction=0.017) or former smokers (p_interaction=0.064) when compared with never smokers and among asthmatics compared with non-asthmatics (p_interaction=0.053). No significant interactions were observed between any GRS and house dust endotoxin.

Conclusions

Evaluation of interactions using GRSs supports a greater impact of increased genetic susceptibility on reduced pulmonary function in the presence of smoking or asthma.

Health outcomes in COPD smokers using heated tobacco products: a 3-year follow-up

Given that many patients with chronic obstructive pulmonary disease (COPD) smoke despite their symptoms, it is important to understand the long-term health impact of cigarette substitution with heated tobacco products (HTPs). We monitored health parameters for 3 years in COPD patients who substantially attenuated or ceased cigarette consumption after switching to HTPs. Changes in daily cigarette smoking, annualized disease exacerbations, lung function indices, patient-reported outcomes (CAT scores) and 6-minute walk distance (6MWD) from baseline were measured in COPD patients using HTPs at 12, 24 and 36 months. These were compared to a group of age- and sex-matched COPD patients who continued smoking. Complete data sets were available for 38 patients (19 in each group). Subjects using HTPs had a substantial decrease in annualized COPD exacerbations within the group mean (± SD) from 2.1 (± 0.9) at baseline to 1.4 (± 0.8), 1.2 (± 0.8) and 1.3 (± 0.8) at 12-, 24- and 36-month follow-up (p < 0.05 for all visits). In addition, substantial and clinically significant improvements in CAT scores and 6MWD were identified at all three time points in the HTP cohort. No significant changes were observed in COPD patients who continued smoking. This study is the first to describe the long-term health effects of HTP use in COPD patients. Consistent improvements in respiratory symptoms, exercise tolerance, quality of life, and rate of disease exacerbations were observed in patients with COPD who abstained from smoking or substantially reduced their cigarette consumption by switching to HTP use.

Prediction of Lung Function in Adolescence Using Epigenetic Aging: A Machine Learning Approach

Epigenetic aging has been found to be associated with a number of phenotypes and diseases. A few studies have investigated its effect on lung function in relatively older people. However, this effect has not been explored in the younger population. This study examines whether lung function in adolescence can be predicted with epigenetic age accelerations (AAs) using machine learning techniques. DNA methylation based AAs were estimated in 326 matched samples at two time points (at 10 years and 18 years) from the Isle of Wight Birth Cohort. Five machine learning regression models (linear, lasso, ridge, elastic net, and Bayesian ridge) were used to predict FEV₁ (forced expiratory volume in one second) and FVC (forced vital capacity) at 18 years from feature selected predictor variables (based on mutual information) and AA changes between the two time points. The best models were ridge regression (R² = 75.21% ± 7.42%; RMSE = 0.3768 ± 0.0653) and elastic net regression (R² = 75.38% ± 6.98%; RMSE = 0.445 ± 0.069) for FEV₁ and FVC, respectively. This study suggests that the application of machine learning in conjunction with tracking changes in AA over the life span can be beneficial to assess the lung health in adolescence.

COPD smokers who switched to e-cigarettes: health outcomes at 5-year follow up

BACKGROUND AND AIMS

The long-term health effects of the use of electronic cigarettes (ECs) in patients with chronic obstructive pulmonary disease (COPD) are largely unexplored. We present findings from a 5-year prospective assessment of respiratory parameters in a cohort of COPD patients who substantially reduced conventional smoking or achieved abstinence by switching to ECs.

METHODS

Patients were evaluated prospectively for their measurements of respiratory exacerbations, spirometric indices, quality of life using the COPD assessment tool (CAT), 6-min walk distance (6MWD), as well as conventional cigarette consumption. Baseline measurements prior to switching to EC use were compared with follow-up visits at 12-, 24-, 48- and 60-months. Age- and sex-matched COPD patients reporting to be regular smokers (not using ECs) were the reference group for the analysis.

RESULTS

Complete data were available from 39 patients. Those in the EC user group achieved a marked decline in cigarette smoking or abstinence. COPD EC users had a significant diminution in COPD exacerbations; with the mean (±SD) exacerbation rate falling from 2.3 (±0.9) at baseline to 1.1 (±1.0) at 5 years (p < 0.001), whereas no significant changes were observed in the control group.Significant and constant improvements in lung function, CAT scores and 6MWD were reported in the EC user group over the 5-year observation period compared with the reference group (p < 0.05).

CONCLUSION

The present study suggests that EC use may ameliorate objective and subjective COPD outcomes, and that the benefits gained appear to persist long term. EC use for abstinence and smoking reduction may ameliorate some of the harm resulting from tobacco smoking in COPD patients.

Association of adult lung function with accelerated biological aging

Lung function, strongly associated with morbidity and mortality, decreases with age. This study examines whether poor adult lung function is associated with age accelerations (AAs). DNA methylation (DNAm) based AAs, lifespan predictors (GrimAge and plasminogen activator inhibitor 1-PAI1) and their related age-adjusted measures were estimated from peripheral blood at two time points (8-to-11 years apart) in adults from two cohorts: SAPALDIA (n=987) and ECRHS (n=509). Within each cohort and stratified by gender (except for estimators from GrimAge and PAI1), AAs were used as predictors in multivariate linear regression with cross-sectional lung function parameters, and in covariate-adjusted mixed linear regression with longitudinal change in lung function and meta-analysed.

AAs were found cross-sectionally associated with lower mean FEV1 (Forced Expiratory Volume in one second) (AA-residuals:P-value=4x10^-4; Intrinsic Epigenetic AA:P-value=2x10^-4) in females at the follow-up time point only, and the same trend was observed for FVC (Forced Vital Capacity). Both lifespan and plasma level predictors were observed strongly associated with lung function decline and the decline was stronger in the follow-up time points (strongest association between FEV1 and DNAmAge GrimAge:P-value=1.25x10^-17).

This study suggests that DNAm based lifespan and plasma level predictors can be utilised as important factors to assess lung health in adults.

Lung function decline in former smokers and low-intensity current smokers: a secondary data analysis of the NHLBI Pooled Cohorts Study

BACKGROUND

Former smokers now outnumber current smokers in many developed countries, and current smokers are smoking fewer cigarettes per day. Some data suggest that lung function decline normalises with smoking cessation; however, mechanistic studies suggest that lung function decline could continue. We hypothesised that former smokers and low-intensity current smokers have accelerated lung function decline compared with never-smokers, including among those without prevalent lung disease.

METHODS

We used data on six US population-based cohorts included in the NHLBI Pooled Cohort Study. We restricted the sample to participants with valid spirometry at two or more exams. Two cohorts recruited younger adults (≥17 years), two recruited middle-aged and older adults (≥45 years), and two recruited only elderly adults (≥65 years) with examinations done between 1983 and 2014. FEV1 decline in sustained former smokers and current smokers was compared to that of never-smokers by use of mixed models adjusted for sociodemographic and anthropometric factors. Differential FEV1 decline was also evaluated according to duration of smoking cessation and cumulative (number of pack-years) and current (number of cigarettes per day) cigarette consumption.

FINDINGS

25 352 participants (ages 17-93 years) completed 70 228 valid spirometry exams. Over a median follow-up of 7 years (IQR 3-20), FEV1 decline at the median age (57 years) was 31·01 mL per year (95% CI 30·66-31·37) in sustained never-smokers, 34·97 mL per year (34·36-35·57) in former smokers, and 39·92 mL per year (38·92-40·92) in current smokers. With adjustment, former smokers showed an accelerated FEV1 decline of 1·82 mL per year (95% CI 1·24-2·40) compared to never-smokers, which was approximately 20% of the effect estimate for current smokers (9·21 mL per year; 95% CI 8·35-10·08). Compared to never-smokers, accelerated FEV1 decline was observed in former smokers for decades after smoking cessation and in current smokers with low cumulative cigarette consumption (<10 pack-years). With respect to current cigarette consumption, the effect estimate for FEV1 decline in current smokers consuming less than five cigarettes per day (7·65 mL per year; 95% CI 6·21-9·09) was 68% of that in current smokers consuming 30 or more cigarettes per day (11·24 mL per year; 9·86-12·62), and around five times greater than in former smokers (1·57 mL per year; 1·00-2·14). Among participants without prevalent lung disease, associations were attenuated but were consistent with the main results.

INTERPRETATION

Former smokers and low-intensity current smokers have accelerated lung function decline compared with never-smokers. These results suggest that all levels of smoking exposure are likely to be associated with lasting and progressive lung damage.

FUNDING

National Institutes of Health, National Heart Lung and Blood Institute, and US Environmental Protection Agency.

Effects of reduced exposure to cigarette smoking on changes in biomarkers of potential harm in adult smokers: results of combined analysis of two clinical studies

Purpose: Nonconventional vapor products (NVP), designed to reduce exposure to cigarette smoke toxicants (CSTs), could cause changes in biomarkers of potential harm (BoPH). Although, NVPs reduced CSTs exposure compared to conventional cigarettes (CC), the changes in the BoPH values varied among the studies. Hence, further information on BoPH using NVPs is needed. Material and methods: The data of two similarly designed studies using a kind of NVP, a noncombustion and nonheating inhaler type of smokeless tobacco product (NCIT) used under 31-day confinement, were pooled, and the differences in 15 BoPH between smokers and nonsmokers at baseline and between the 1 mg tar CC (CC1) group and NCIT group at Day 28/29 were analyzed. Results: At baseline, the levels of eight BoPH (red blood cells, white blood cells, 8-epi-prostaglandin F2α, 8-hydroxy-2'-deoxyguanosine, malondialdehyde, 11-dehydrothromboxane B2, total cholesterol and glucose) were significantly different between smokers and nonsmokers. At Day 28/29, the levels of six BoPH were significantly different between NCIT and CC1 (8-epi-prostaglandin F2α, malondialdehyde, 11-dehydrothromboxane B2: CC1 > NCIT, total bilirubin, low-density lipoprotein cholesterol and total cholesterol: CC1 < NCIT). Conclusions: Reduced exposure to CSTs has favorable effects on BoPH associated with oxidative stress, antioxidant capacity and platelet activation/coagulation but not in lipid metabolism.

Rate of normal lung function decline in ageing adults: a systematic review of prospective cohort studies

OBJECTIVE

To conduct a systematic review investigating the normal age-related changes in lung function in adults without known lung disease.

DESIGN

Systematic review.

DATA SOURCES

MEDLINE, Embase and Cumulative Index to Nursing and Allied Health Literature (CINAHL) were searched for eligible studies from inception to February 12, 2019, supplemented by manual searches of reference lists and clinical trial registries.

ELIGIBILITY CRITERIA

We planned to include prospective cohort studies and randomised controlled trials (control arms) that measured changes in lung function over time in asymptomatic adults without known respiratory disease.

DATA EXTRACTION AND SYNTHESIS

Two authors independently determined the eligibility of studies, extracted data and assessed the risk of bias of included studies using the modified Newcastle-Ottawa Scale.

RESULTS

From 4385 records screened, we identified 16 cohort studies with 31 099 participants. All included studies demonstrated decline in lung function-forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) with age. In studies with longer follow-up (>10 years), rates of FEV1 decline ranged from 17.7 to 46.4 mL/year (median 22.4 mL/year). Overall, men had faster absolute rates of decline (median 43.5 mL/year) compared with women (median 30.5 mL/year). Differences in relative FEV1 change, however, were not observed between men and women. FEV1/FVC change was reported in only one study, declining by 0.29% per year. An age-specific analysis suggested the rate of FEV1 function decline may accelerate with each decade of age.

CONCLUSIONS

Lung function-FEV1, FVC and PEFR-decline with age in individuals without known lung disease. The definition of chronic airway disease may need to be reconsidered to allow for normal ageing and ensure that people likely to benefit from interventions are identified rather than healthy people who may be harmed by potential overdiagnosis and overtreatment. The first step would be to apply age, sex and ethnicity-adjusted FEV1/FVC thresholds to the disease definition of chronic obstructive pulmonary disease.

PROSPERO REGISTRATION NUMBER

CRD42018087066.

Acute respiratory responses to the use of e-cigarette: an intervention study

The goal of our study was to assess acute respiratory responses to using e-cigarettes in exclusive e-cigarette users (E-Group) and dual users (T/E-Group) and to compare these effects with responses to smoking tobacco-cigarettes in tobacco smokers (T-Group). The study included 120 adults (age: 21.7 ± 2.1 years) divided into 4 groups (n = 30 each): Controls, T-, E-, T/E-Group. Spirometric status, O2 saturation, exhaled FeNO levels, exhaled CO levels, and airway temperature were assessed before the use of an e-cigarette (E-, T/E-Group) or tobacco cigarette as well as 'minute 1' and 'minute 30' after smoking. Controls used an e-cigarette without e-liquid. Lower (p < 0.05) baseline values of FeNO were found in T-Group (15.4 ppb) and in T/E-Group (15.0 ppb) than in Controls (19.6 ppb). Following exposure, and compared with Controls, T-, and T/E-Group had a significant decrease (p < 0.05) in PEF and MEF75. Mean FeNO values decreased on 'minute 1' in T-Group (by 2.1 ppb), E-Group (by 1.5 ppb) and in T/E-Group (by 2.2 ppb). Other effects included increase in temperature of exhaled air (p < 0.05). The use of e-cigarettes is associated with decreased FeNO and airflow indices (PEF, MEF75), but an increase in airway temperature. These changes are similar to those after exposure to tobacco cigarette smoke.

Health effects in COPD smokers who switch to electronic cigarettes: a retrospective-prospective 3-year follow-up

Background

Health effects of electronic cigarette (EC) use in patients with chronic obstructive pulmonary disease (COPD) are largely unexplored.

Aim

We present findings from a long-term prospective assessment of respiratory parameters in a cohort of COPD patients who ceased or substantially reduced conventional cigarette use with ECs.

Methods

We prospectively re-evaluated COPD exacerbations, spirometric indices, subjective assessments (using the COPD Assessment Tool [CAT] scores), physical activity (measured by the 6-minute walk distance [6MWD]), and conventional cigarette use in EC users with COPD who were retrospectively assessed previously. Baseline measurements prior to switching to EC use were compared to follow-up visits at 12, 24, and 36 months. Age- and sex-matched regularly smoking COPD patients who were not using ECs were included as reference (control) group.

Results

Complete data were available from 44 patients. Compared to baseline in the EC-user group, there was a marked decline in the use of conventional cigarettes. Although there was no change in lung function, significant improvements in COPD exacerbation rates, CAT scores, and 6MWD were observed consistently in the EC user group over the 3-year period (p<0.01). Similar findings were noted in COPD EC users who also smoked conventional cigarettes (“dual users”).

Conclusion

The present study suggests that EC use may ameliorate objective and subjective COPD outcomes and that the benefits gained may persist long-term. EC use may reverse some of the harm resulting from tobacco smoking in COPD patients.

Respiratory function in healthy ever-smokers is impaired by smoking habits in a dose-dependent manner

BACKGROUND

There is limited information about the respiratory function of ever-smokers without lung disorders. We sought to assess the effects of smoking habits on respiratory function in subjects without lung disorders.

METHODS

Subjects were recruited from among patients without any evidence of respiratory disorders who visited rural primary care clinics. Each participant was asked to answer a questionnaire that included questions smoking history. Their forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were measured.

RESULTS

We analyzed 802 subjects (364 men and 438 women). The means of the lambda-mu-sigma method derived z-score of FEV1 (zFEV1) both in current-smokers and ex-smokers were lower than that in never-smokers. The mean zFEV1 in the ever-smokers with more than 30 pack-years of smoking history were lower than that in the ever-smokers with less smoking history. Univariate analysis showed that there were significant negative correlations between pack-years and zFEV1 both in the ex-smokers and current-smokers. There was no significant correlation between the duration of smoking cessation and zFEV1 in the ex-smokers.

CONCLUSIONS

Our data suggests that respiratory function in healthy ever-smokers is decreased based on smoking habits in a dose-dependent manner. Even after a long period of smoking cessation, the decreased respiratory function seems to be maintained in ex-smokers.

Amount of smoking, pulmonary function, and bone mineral density in middle-aged Korean men: KNHANES 2008-2011

Smoking induces bone loss; however, data on the relationship between smoking history and bone mineral density (BMD) are lacking. Age and pulmonary function can affect BMD. We investigated the relationships among pack-years (PYs) of smoking, pulmonary function, and BMD in middle-aged Korean men (50-64 years old). This cross-sectional study used data from the Korean National Health and Nutrition Examination Survey, 2008-2011. All participants underwent BMD measurements using dual energy X-ray absorptiometry and pulmonary function tests using standardized spirometry. In total, 388 never-smokers and 1088 ever-smokers were analyzed. The number of PYs of smoking was negatively correlated with total hip BMD (r = -0.088; P = 0.004) after adjusting for age, height, and weight. Ever-smokers were classified into 3 groups according to PYs of smoking. The highest tertile (n = 482) exhibited significantly lower total hip bone mass than the lowest tertile (n = 214) after adjusting for confounding factors (age, height, weight, forced expiratory volume in 1 s (FEV₁), alcohol consumption, physical activity, and vitamin D levels) that could affect bone metabolism (P = 0.003). In conclusion, smoking for >30 PYs was significantly associated with low hip BMD after adjusting for pulmonary function in middle-aged Korean men. Long-term smoking may be a risk factor for bone loss in middle-aged men independent of age, height, weight, and pulmonary function.

E-cigarettes in patients with COPD: current perspectives

Conventional cigarette smoking is known to result in significant COPD morbidity and mortality. Strategies to reduce and/or stop smoking in this highly vulnerable patient group are key public health priorities to reduce COPD morbidity and mortality. Unfortunately, smoking cessation efforts in patients with COPD are poor and there is a compelling need for more efficient approaches to cessation for patients with COPD. Electronic cigarettes (ECs) are devices that use batteries to vaporize nicotine. They may facilitate quit attempts and cessation in many smokers. Although they are not risk free, ECs are much less harmful than tobacco smoking. Hence, the use of ECs in vulnerable groups and in patients with challenges to abstain or multiple relapses to this habit may be promising. To date, little is known about health consequences of EC use among COPD smokers and whether their regular use has any effects on subjective and objective COPD outcomes. In the current review, we discuss the current perspectives and literature on the role of ECs in abstaining from conventional smoking and the effects of ECs on the respiratory tract in patients with COPD.

The impact of BMI on non-malignant respiratory symptoms and lung function in arsenic exposed adults of Northern Chile

BACKGROUND

Elevated body mass index (BMI) and arsenic are both associated with cancer and with non-malignant lung disease. Using a unique exposure situation in Northern Chile with data on lifetime arsenic exposure, we previously identified the first evidence of an interaction between arsenic and BMI for the development of lung cancer.

OBJECTIVES

We examined whether there was an interaction between arsenic and BMI for the development of non-malignant lung disease.

METHODS

Data on lifetime arsenic exposure, respiratory symptoms, spirometry, BMI, and smoking were collected from 751 participants from cities in Northern Chile with varying levels of arsenic water concentrations. Spirometry values and respiratory symptoms were compared across subjects in different categories of arsenic exposure and BMI.

RESULTS

Adults with both a BMI above the 90th percentile (>33.9kg/m²) and arsenic water concentrations ≥11µg/L exhibited high odds ratios (ORs) for cough (OR = 10.7, 95% confidence interval (CI): 3.03, 50.1), shortness of breath (OR = 14.2, 95% CI: 4.79, 52.4), wheeze (OR = 14.4, 95% CI: 4.80, 53.7), and the combined presence of any respiratory symptom (OR = 9.82, 95% CI: 4.22, 24.5). In subjects with lower BMIs, respiratory symptom ORs for arsenic water concentrations ≥11µg/L were markedly lower. In never-smokers, reductions in forced vital capacity associated with arsenic increased as BMI increased. Analysis of the FEV₁/FVC ratio in never-smokers significantly increased as BMI and arsenic concentrations increased. Similar trends were not observed for FEV₁ alone or in ever-smokers.

CONCLUSIONS

This study provides preliminary evidence that BMI may increase the risk for arsenic-related non-malignant respiratory disease.

Difficulties Quitting for Smokers with and without a Respiratory Disease and Use of a Tailored Intervention for Smoking Cessation – A Qualitative Study

Introduction: Smokers with respiratory diseases are less likely to quit than those without impaired lung function, yet few studies have investigated the effectiveness of smoking cessation interventions with this population, and none have used a computer-tailored approach.

Aims: This paper aims to fill this gap in the literature by exploring smokers’ experiences when trying to quit and their perceptions of a computer-tailored intervention.

Methods: Semi-structured interviews were conducted with 26 smokers recruited from six general practises in North London. Thematic analysis was conducted to examine participants’ previous experiences of quitting and their perceptions of receiving personal tailored feedback reports to aid smoking cessation.

Results: Participants discussed how their positive smoking experiences coupled with their negative cessation experiences led to conflicts with quitting smoking. Although the computer-tailored intervention was key in prompting quit attempts and participants valued its personal approach; it was not sufficient as a stand-alone intervention.

Conclusions: The results highlight the difficulties that smokers experience when quitting and the need for a more personalised stop smoking service in smokers with respiratory diseases. The study also demonstrates the application and potential for computer-tailored intervention as part of a wider programme of long-term smoking cessation.

Adult onset asthma and interaction between genes and active tobacco smoking: The GABRIEL consortium

Background

Genome-wide association studies have identified novel genetic associations for asthma, but without taking into account the role of active tobacco smoking. This study aimed to identify novel genes that interact with ever active tobacco smoking in adult onset asthma.

Methods

We performed a genome-wide interaction analysis in six studies participating in the GABRIEL consortium following two meta-analyses approaches based on 1) the overall interaction effect and 2) the genetic effect in subjects with and without smoking exposure. We performed a discovery meta-analysis including 4,057 subjects of European descent and replicated our findings in an independent cohort (LifeLines Cohort Study), including 12,475 subjects.

Results

First approach: 50 SNPs were selected based on an overall interaction effect at p<10⁻⁴. The most pronounced interaction effect was observed for rs9969775 on chromosome 9 (discovery meta-analysis: OR_int = 0.50, p = 7.63*10⁻⁵, replication: OR_int = 0.65, p = 0.02). Second approach: 35 SNPs were selected based on the overall genetic effect in exposed subjects (p <10⁻⁴). The most pronounced genetic effect was observed for rs5011804 on chromosome 12 (discovery meta-analysis OR_int = 1.50, p = 1.21*10^−4; replication: OR_int = 1.40, p = 0.03).

Conclusions

Using two genome-wide interaction approaches, we identified novel polymorphisms in non-annotated intergenic regions on chromosomes 9 and 12, that showed suggestive evidence for interaction with active tobacco smoking in the onset of adult asthma.

Evidence for harm reduction in COPD smokers who switch to electronic cigarettes

BACKGROUND

Electronic cigarettes (ECs) are battery-operated devices designed to vaporise nicotine, which may help smokers quitting or reducing their tobacco consumption. There is a lack of data on the health effects of EC use among smokers with COPD and whether regular use results in improvement in subjective and objective COPD outcomes. We investigated long-term changes in objective and subjective respiratory outcomes in smokers with a diagnosis of COPD who quit or reduced substantially their tobacco consumption by supplementing with or converting only to ECs use.

METHODS

We conducted a retrospective chart review of patients with COPD to identify those reporting regular daily use of ECs on at least two follow-up visits at 12- (F/up1) and 24-months (F/up2). Regularly smoking COPD patients were included as a reference group.

RESULTS

A marked reduction in cigarette consumption was observed in ECs users. A significant reduction in COPD exacerbations was reported in the COPD EC user group, their mean (±SD) decreasing from 2.3 (±1) at baseline to 1.8 (±1; p = 0.002) and 1.4 (±0.9; p < 0.001) at F/up1 and F/up2 respectively. A significant reduction in COPD exacerbations was also observed in ECs users who also smoked conventional cigarettes (i.e. 'dual users'). COPD symptoms and ability to perform physical activities improved statistically in the EC group at both visits, with no change in the control group.

CONCLUSIONS

These findings suggest that ECs use may aid smokers with COPD reduce their cigarette consumption or remain abstinent, which results in marked improvements in annual exacerbation rate as well as subjective and objective COPD outcomes.

TRPM8 genetic variations associated with COPD risk in the Chinese Han population

TRPM8 plays a key role in COPD. The development of pulmonary hypertension (PH) in COPD adversely affects survival and exercise capacity. Thus, the aim of this study was to evaluate the possible association between single nucleotide polymorphisms (SNPs) in TRPM8 and COPD or PH in COPD among the Chinese Han population. A total of 513 COPD patients and 506 controls were enrolled in the study. Six tag SNPs (tSNPs) were genotyped. The relationship between COPD or PH in COPD and the six tSNPs was evaluated using the χ² test and genetic model analysis. In the rs9789398 polymorphism, the T/C genotype was associated with an increased risk for COPD (P=0.005). Under the assumption of models of inheritance, there was an association between the rs9789398 polymorphism and COPD. In the rs9789675 polymorphism, the G/A genotype was associated with an increased risk for COPD (P=0.021). Furthermore, by the χ² test, we found that the minor allele “A” of rs9789675 (odds ratio [OR] =0.63, 95% confidence interval [CI], 0.42–0.97, P=0.034) and the minor allele “C” of rs9789398 (OR =1.59, 95% CI, 1.03–2.44, P=0.034) were associated with a decreased risk of PH in COPD in allele models. In genetic models, the genotypes “GA” and “AA” of rs9789675 were associated with a decreased risk of PH in COPD. The genotypes “TC” and “CC” of rs9789398 were associated with a decreased risk of PH in COPD. Moreover, “CG” of rs1004478 was significantly associated with a decreased risk of PH in COPD. There was a significant association between the five SNPs (rs2362290, rs9789675, rs9789398, rs1003540, and rs104478) in the TRPM8 gene and the risk of PH in COPD. Our findings indicated that rs9789398 in the TRPM8 gene was significantly associated with the risk of COPD in the Chinese Han population. Moreover, rs9789675, rs9789398, and rs1004478 were significantly associated with the risk of PH in COPD. This study provides a novel insight into COPD and PH in the development of COPD.

Non-pharmacological treatments for COPD

Chronic obstructive pulmonary disease (COPD) affects roughly 10% of the global population and is growing in prevalence annually. COPD is characterized by progressive non-reversible narrowing of airways mainly due to cigarette smoking. Therapeutic interventions aimed at altering this progressive disease course can largely be grouped into pharmacological or non-pharmacological therapies. The focus of this paper is on the non-pharmacological aspects of COPD management, reviewing the current literature to provide an evidence-based management approach. Non-pharmacological therapies reviewed in this article include the implementation of comprehensive care models utilizing a coordinated multidisciplinary team, tele-monitoring and patient-centred approach to optimize COPD care and improve compliance. Preventing progression of COPD via smoking cessation remains of paramount importance, and newer therapeutic options including electronic cigarettes show promise in small studies as cessation aids. COPD has systemic manifestations that can be ameliorated with the enrollment in pulmonary rehabilitation programmes, which focus on exercise endurance to improve dyspnoea and quality of life. Advanced therapeutics for COPD includes lung volume reduction surgery for a pre-specified cohort and minimally invasive bronchoscopic valves that in recent reviews show promise. Lastly, patients on maximal COPD therapy with progressive disease can be referred for lung transplantation; however, this often requires a highly selected and motivated patient and care team. Survival rates for lung transplantation are improving; thus, this procedure remains a viable option as more expertise and experience are gained.

Lung Function Trajectories in World Trade Center-Exposed New York City Firefighters Over 13 Years: The Roles of Smoking and Smoking Cessation

BACKGROUND

World Trade Center (WTC)-exposed Fire Department of the City of New York firefighters lost, on average, 10% of lung function after September 11, 2011, and >10% developed new obstructive airways disease. There was little recovery (on average) over the first 6 years. Follow-up into the next decade allowed us to determine the longer-term exposure effects and the roles of cigarette smoking and cessation on lung function trajectories.

METHODS

We examined serial measurements of FEV1 from March 11, 2000, to September 10, 2014, among 10,641 WTC-exposed Fire Department of the City of New York firefighters with known smoking and body weight histories.

RESULTS

The median number of FEV1 measurements during follow-up was 9; 15% of firefighters arrived at the WTC during the morning of September 11, 2001; and 65% never smoked. Firefighters arriving the morning of September 11, 2001 averaged lower lung function than did lesser exposed firefighters; this difference remained significant during most of follow-up (P < .05). Never smokers had significantly better lung function than current smokers; former smokers fell in between, depending upon their cessation date. Those arriving the morning of September 11, 2001 were more likely to have an FEV1 < lower limits of normal compared with those arriving between September 13, 2001, and September 24, 2001 (OR = 1.70, P < .01). Current smokers were more likely to have an FEV1 < lower limits of normal compared with never smokers (OR = 2.06, P < .01), former smokers who quit before September 11, 2001 (OR = 1.96, P < .01), or those who quit between September 11, 2001 and March 10, 2008 (OR = 1.49, P < .01).

CONCLUSIONS

Thirteen years after September 11, 2001, most firefighters continued to show a lack of lung function recovery, with the trajectory of decline differing by WTC exposure and smoking status. Unlike the immutable effect of WTC exposure, we demonstrated the benefit on lung function of smoking cessation in this unique occupational/environmental cohort.

Twelve Weeks of Successful Smoking Cessation Therapy with Varenicline Reduces Spirometric Lung Age

Objective We evaluated the short-term effects of smoking cessation therapy with varenicline on the lung function. Methods In this study, 81 subjects received 12 weeks of smoking cessation therapy with varenicline. No changes were made to any previously prescribed medications. A physical examination, blood sampling, and spirometry were performed at the first and last visit. Spirometric lung ages were calculated by a formula based on height and the forced expiratory volume in 1 second. The success group comprised 62 subjects who attained 4-week continuous abstinence confirmed by exhaled carbon monoxide testing; whereas the failure group comprised 19 subjects who did not attain this result. However, the number of cigarettes consumed per day was reduced in all subjects of the failure group. Results The spirometric lung ages significantly improved over the 12-week period in the success group (69.8±24.7 vs. 66.9±24.1, p<0.01); however, spirometric lung ages significantly deteriorated in the failure group (70.5±25.5 vs. 73.7±26.9, p<0.01). The effect sizes (Cohen's d) of spirometric lung age in the success and failure groups were 0.37 and 0.81, respectively. The post-hoc statistical power of the spirometric lung age in the success and failure groups was 0.83 and 0.91, respectively. According to a multiple regression analysis, success in smoking cessation exhibited an independent association with the difference in spirometric lung age between the last visit and baseline (p<0.01). Conclusion These findings suggest that successful smoking cessation therapy with varenicline improves the spirometric lung age in the short term.

Klotho Reduction in Alveolar Macrophages Contributes to Cigarette Smoke Extract-induced Inflammation in Chronic Obstructive Pulmonary Disease

Abnormal inflammation and accelerated decline in lung function occur in patients with chronic obstructive pulmonary disease (COPD). Klotho, an anti-aging protein, has an anti-inflammatory function. However, the role of Klotho has never been investigated in COPD. The aim of this study is to investigate the possible role of Klotho by alveolar macrophages in airway inflammation in COPD. Klotho levels were assessed in the lung samples and peripheral blood mononuclear cells of non-smokers, smokers, and patients with COPD. The regulation of Klotho expression by cigarette smoke extract (CSE) was studied in vitro, and small interfering RNA (siRNA) and recombinant Klotho were employed to investigate the role of Klotho on CSE-induced inflammation. Klotho expression was reduced in alveolar macrophages in the lungs and peripheral blood mononuclear cells of COPD patients. CSE decreased Klotho expression and release from MH-S cells. Knockdown of endogenous Klotho augmented the expression of the inflammatory mediators, such as MMP-9, IL-6, and TNF-α, by MH-S cells. Exogenous Klotho inhibited the expression of CSE-induced inflammatory mediators. Furthermore, we showed that Klotho interacts with IκBα of the NF-κB pathway. Dexamethasone treatment increased the expression and release level of Klotho in MH-S cells. Our findings suggest that Klotho plays a role in sustained inflammation of the lungs, which in turn may have therapeutic implications in COPD.

Acetylation of lysine 9 on histone H3 is associated with increased pro-inflammatory cytokine release in a cigarette smoke-induced rat model through HDAC1 depression

OBJECTIVE AND DESIGN

Cigarette smoke (CS)-induced inflammation is critical in chronic obstructive pulmonary disease (COPD). However, the role of acetylation at histone 3 lysine 9 (H3K9) in COPD inflammation remains unclear. The present study assessed the effect of acetylation of H3K9 on transcription both in rat lungs and in macrophages.

METHODS

Sprague-Dawley rats were exposed to CS for either 6 or 12 weeks and rat lungs were collected. Rat macrophages were subjected to 20 % cigarette smoke extract (CSE) for 48 h.

RESULTS

CS increased MCP-1 and IL-8 expressions at both mRNA and protein levels in rat lungs after 6 and 12 weeks; increased TNF-α and MMP9 expressions at both levels were noted only after 12 weeks. CSE increased these genes expression in macrophages after 48 h exposure. Increased abundance of acetylated H3K9 protein in rat lungs and in macrophages were associated with decreased expression of histone deacetylase-1(HDAC1). Chromatin immunoprecipitation demonstrated increased level of acetylated H3K9 on promoter regions of these genes both in vivo and in vitro. Knockdown of HDAC1 increased these genes mRNA expression.

CONCLUSIONS

CS increased H3K9 acetylation and subsequently altered the expression of pro-inflammatory mediators and protease genes through HDAC1 depression in CS-induced rat lungs and in macrophages.

Associations of ABHD2 genetic variations with risks for chronic obstructive pulmonary disease in a Chinese Han population

The human α/β hydrolase domain-containing protein 2 gene (ABHD2) plays a critical role in pulmonary emphysema, a major subset of the clinical entity known as chronic obstructive pulmonary disease (COPD). Here, we evaluated genetic variation in the ABHD2 gene in a Chinese Han population of 286 COPD patients and 326 control subjects. The rs12442260 CT/CC genotype was associated with COPD (P < 0.001) under a dominant model. In the former-smoker group, the rs12442260 TT genotype was associated with a decreased risk of developing COPD after adjusting for age, gender and pack-years (P = 0.012). Rs12442260 was also associated with pre-FEV1 (the predicted bronchodilator forced expiratory volume in the first second) in controls (P = 0.027), but with FEV1/ forced vital capacity (FVC) ratios only in COPD patients (P = 0.012) under a dominant model. Results from the current study suggest that ABHD2 gene polymorphisms contribute to COPD susceptibility in the Chinese Han population.

Real-world comparative study of behavioral group therapy program vs education program implemented for smoking cessation in community-dwelling elderly smokers

BACKGROUND

Tobacco smoking is known to be an important contributor to a wide variety of chronic diseases, especially in older adults. Information on health policy and practice, as well as evaluation of smoking cessation programs targeting older people, is almost nonexistent.

PURPOSE

To compare the real-world implementation of behavioral group therapy in relation to education alone for elderly smokers.

MATERIALS AND METHODS

Elderly smokers ready to quit smoking were identified from a cohort who completed a questionnaire at a smoking exhibition. They were allocated into two groups, behavioral therapy (3 days 9 hours) and education (2 hours), depending on their preferences. Demographic data, the Fagerstrom test for nicotine dependence (FTND) score, and exhaled carbon monoxide level were recorded at baseline. Smoking status of all subjects was followed at months 3, 6, and 12. Statistical differences in continuous abstinence rate (CAR) between the two groups were analyzed using chi-square tests.

RESULTS

Two hundred and twenty-four out of 372 smoking exhibition attendants met the enrollment criteria; 120 and 104 elected to be in behavioral group therapy and education-alone therapy, respectively. Demographic characteristics and smoking history were similar between both groups, including age, age of onset of smoking, years of smoking, smoking pack-years, education level, and nicotine dependence as measured by the FTND scale. The CAR of the behavioral therapy group at the end of the study (month 12) was significantly higher than the education group (40.1% vs 33.3%, P=0.034). Similar results were also found throughout all follow-up visits at month 3 (57.3% vs 27.0%, P<0.001) and month 6 (51.7% vs 25%, P<0.001).

CONCLUSION

Behavioral group therapy targeting elderly smokers could achieve higher short-and long-term CARs than education alone in real-world practice.

COPD: early diagnosis and treatment to slow disease progression

AIMS

Chronic obstructive pulmonary disease (COPD) is usually a progressive condition. Undiagnosed early-stage disease, particularly in symptomatic patients, is likely to become more severe with time. Hence, prevention or reduction in disease progression is highly relevant. We evaluated the published data and discussed the potential impact of early intervention on the course of COPD.

METHODS

We performed PubMed searches of studies in early or mild COPD, focusing on those relating to lung function decline.

RESULTS

Smoking cessation reduced lung function decline at all stages of COPD, and the earlier the intervention, the greater the impact on lung function. Accumulating data from placebo-controlled trials suggested that long-acting bronchodilators can slow the decline in lung function, as well as reduce exacerbation and mortality rates and improve health-related quality of life (HRQoL) in patients with mild-to-moderate COPD. Inhaled corticosteroids (ICS) do not impact lung function in early COPD, and further research is needed on the role of long-acting β2-agonist-ICS combination therapy in these patients.

CONCLUSIONS

Initiating treatment early in the course of COPD is likely to slow disease progression and improve HRQoL. Current data support maintenance treatment with a long-acting bronchodilator in this patient group. However, many questions remain unanswered regarding the optimal treatment of mild COPD, and further research is required to develop evidence-based recommendations in this field.

Current smoking and reduced gray matter volume-a voxel-based morphometry study

Nicotine modulates prefrontal processing when tested with functional imaging. Previous studies on changes in regional brain volumes in small samples, reporting different life-time exposure to nicotine, identified reduced volume in smokers in prefrontal areas but reported controversial results for other areas. We investigated the association of cigarette smoking and regional gray and white matter volume by using voxel-based morphometry (VBM) for T1-weighted high-resolution magnetic resonance imaging in 315 current-smokers and 659 never-smokers from the representative Study of Health in Pomerania (SHIP). Our study showed that in current-smokers smoking is significantly associated with gray matter volume loss in the prefrontal cortex, the anterior cingulate cortex, the insula, and the olfactory gyrus. White matter volumes were not relevantly reduced in current-smokers. In current-smokers, we found associations of gray matter loss and smoking exposure (pack-years) in the prefrontal cortex, the anterior and middle cingulate cortex, and the superior temporal and angular gyrus, which however did not stand corrections for multiple testing. We confirmed associations between smoking and gray matter differences in the prefrontal cortex, the anterior cingulate cortex and the insula in the general population of Pomerania (Germany). For the first time, we identified differences in brain volumes in the olfactory gyrus. Other cerebral regions did not show significant differences when correcting for multiple comparisons within the whole brain. The regions of structural deficits might be involved in addictive behavior and withdrawal symptoms, whereas further investigations have to show if the observed atrophies were caused by smoking itself or are preexisting differences between smoking and non-smoking individuals.

Effects of smoking on chest expansion, lung function, and respiratory muscle strength of youths

[Purpose] Smoking has a direct effect on the respiratory system. The rate of cigarette smoking among young people has continued to increase steadily. The present study quantified and compared the respiratory function of smoking and non-smoking youths. [Subjects] Smoking and non-smoking male participants aged between 15 to 18 years were recruited (n=34 per group). [Methods] Participants were asked to complete a questionnaire relating to smoking habits and the Fagerström test for nicotine dependence questionnaire, and their respiratory function was tested (measurement of chest expansion, lung function test with a spirometer, and assessment of respiratory muscle strength). [Results] All respiratory function tests demonstrated significant differences between the smoking and non-smoking groups. Smokers initiated cigarette smoking between the ages of 15 to 18 years. The most common duration of cigarette smoking was 1-3 years and the degree of nicotine dependence among the youths was at a low level. [Conclusion] This study’s findings show that the early effects of cigarette smoking found in youths can lead to problems with the respiratory system. Such information can be used to illustrate the harm of smoking and should be used to encourage young people to quit or avoid cigarette smoking.

The clinical and economic burden of chronic obstructive pulmonary disease in the USA

Chronic obstructive pulmonary disease (COPD) is the third most common cause of death in the USA. In 2010, the cost of COPD in the USA was projected to be approximately US$50 billion, which includes $20 billion in indirect costs and $30 billion in direct health care expenditures. These costs can be expected to continue to rise with this progressive disease. Costs increase with increasing severity of disease, and hospital stays account for the majority of these costs. Patients are diagnosed with COPD following a multifactorial assessment that includes spirometry, clinical presentation, symptomatology, and risk factors. Smoking cessation interventions are the most influential factor in COPD management. The primary goal of chronic COPD management is stabilization of chronic disease and prevention of acute exacerbations. Bronchodilators are the mainstay of COPD therapy. Patients with few symptoms and low exacerbation risk should be treated with a short-acting bronchodilator as needed for breathlessness. Progression of symptoms, as well as possible decline in forced expiratory volume in the first second of expiration (FEV1), warrant the use of long-acting bronchodilators. For patients with frequent exacerbations with or without consistent symptoms, inhaled corticosteroids should be considered in addition to a long-acting beta2-agonist (LABA) or long-acting muscarinic antagonist (LAMA) and may even consist of "triple therapy" with all three agents with more severe disease. Phosphodiesterase-4 inhibitors may be an option in patients with frequent exacerbations and symptoms of chronic bronchitis. In addition to a variety of novel ultra-LABAs, LAMAs and combination bronchodilator and inhaled corticosteroid (ICS) therapies, other bronchodilators with a variety of mechanisms are also being considered, to expand therapeutic options for the treatment of COPD. With more than 50 new medications in the pipeline for the treatment of COPD, optimal management will continue to evolve and grow more complex as benefits of therapy are balanced with the limitations and needs of each patient.

Serum heme oxygenase-1 as a marker of lung function decline in patients with chronic silicosis

OBJECTIVE

To identify predictive factors of excess decline in forced expiratory volume in one second (FEV1) in patients with chronic silicosis.

METHODS

Forty-six male patients enrolled in 2004 were screened and received pulmonary function tests.

RESULTS

Among the 33 included patients, 12 were categorized as rapid decliners (reduction in FEV1 > 60 mL/yr). The mean level of serum heme oxygenase-1 (HO-1), a marker of oxidative stress, was significantly lower in rapid decliners than in normal decliners (P = 0.002). Logistic regression analysis revealed that serum HO-1 was a factor affecting clinically important decline in FEV1 (odds ratio = 0.52; 95% confidence interval, 0.31 to 0.88) independent of the effects of age, height, weight, smoking, exposure status, and C-reactive protein.

CONCLUSIONS

Serum HO-1 may be a predictor of lung function decline in silicosis patients.

Bronchial responsiveness, spirometry and mortality in a cohort of adults

OBJECTIVE

Prospective population studies have reported that pulmonary function, measured by forced expiratory volume in one second (FEV(1)), is an independent predictor for mortality. Besides, several studies found that death from all causes is higher in asthmatics than in non-asthmatics. However, none of these studies examined whether bronchial hyperresponsiveness (BHR), one of the key features in asthma, can be used as a predictor for mortality. Thus, the aim of this study was to analyze the association between BHR, FEV(1), and all-cause mortality in a population-based cohort of adults.

METHODS

Within the cross-sectional survey ECRHS-I Erfurt (1990-1992), 1162 adults aged 20-65 years performed lung function tests, including spirometry and BHR testing by methacholine inhalation up to a cumulative dose of 2 mg. BHR was assessed from the methacholine dose nebulized at ≥ 20% fall of FEV(1). After circa 20 years of follow-up, the association between baseline lung function, BHR, and mortality was investigated.

RESULTS

A total of 85 individuals (7.3%) died during a mean follow-up period of 17.4 years (SD = 2.4). FEV(1), but not forced vital capacity (FVC), was a predictor for mortality. In men, BHR increased the mortality risk (OR = 2.6, 95% CI: 1.3-5.3; adjusted for age and BMI). Additional adjustment for asthma did not change the results (OR = 2.4, 95% CI: 1.2-5.0). However, after an additional adjustment for pack years of cigarette smoking or airway obstruction, the association was not statistically significant anymore (OR = 1.8, 95% CI: 0.8-4.0, OR = 1.9, 95% CI: 0.9-4.3, respectively).

CONCLUSIONS

BHR was associated with an increased mortality risk in men. Potential explanatory factors for this association are cigarette smoking, chronic obstructive pulmonary disease (COPD), or asthma. Thus, BHR might be an indirect predictor for all-cause mortality. FEV(1) was an independent predictor for all-cause mortality.

Rationale for earlier treatment in COPD: a systematic review of published literature in mild-to-moderate COPD

COPD is progressive and typically begins many years before a definite diagnosis is made. As the rate of decline in lung function may be faster in the initial stages of the disease, early intervention could be beneficial to control symptoms and affect disease progression and outcomes. A systematic review of published literature relating to mild-to-moderate COPD (patients with FEV(1) ≥50% predicted) was performed to evaluate the level of impairment and natural history or disease progression over time, and impact of interventions on the outcomes of patients with early-stage disease. Of the 79 published articles included in this analysis, 31 reported randomized controlled trials; the remaining 48 articles reported studies of non-randomized and/or observational design. Nine of the randomized controlled trials were ≥6 months' duration, enabling assessment of outcomes over time. Most of the randomized controlled trials were in patients with moderate COPD (GOLD stage II); few included patients with the mildest stages of the disease (i.e., stage I). The results show that even patients with milder or moderate COPD can have substantial limitations and physical impairment, which worsen over time. Encouragement of smoking cessation, in conjunction with management of symptoms and treating activity limitation and exacerbations by appropriate non-pharmacologic and pharmacologic management at the earliest possible stage, could positively affect the impact and progression of the disease.