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

Background: Chronic obstructive pulmonary disease (COPD) has become one of the most significant chronic diseases in China. According to conventional wisdom, smoking is the pathogenic factor. However, current research indicates that the pathophysiology of COPD may be associated with prior respiratory system events (e.g., childhood hospitalization for pneumonia, chronic bronchitis) and environmental exposure (e.g., dust from workplace, indoor combustion particles). Dyspnea, persistent wheezing, and other respiratory symptoms further point to the need for pulmonary function tests in this population. Reducing the burden of chronic diseases in China requires a thorough understanding of the various factors that influence the occurrence of COPD. Methods: Using a cohort from the natural population, this study used nested case-control analysis. We carried out a number of researches, including questionnaire surveys and pulmonary function testing, in the Northwest and Southeast cohorts of China between 2014 and 2021. After removing any variations in the baseline data between patients and control subjects using propensity score matching analysis, the risk factors were examined using univariate or multivariate regression. Result: It was discovered that prior history of chronic bronchitis, long-term wheezing symptoms, and environmental exposure-including smoking and biofuel combustion-were risk factors for COPD. Dyspnea, symptoms of mobility limitation, organic matter, and a history of hospitalization for pneumonia at an early age were not significant in the clinical model but their incidence in COPD group is higher than that in healthy population. Discussion: COPD screening effectiveness can be increased by looking for individuals with chronic respiratory symptoms. Smokers should give up as soon as they can, and families that have been exposed to biofuels for a long time should convert to clean energy or upgrade their ventilation. Individuals who have previously been diagnosed with emphysema and chronic bronchitis ought to be extra mindful of the prevention or advancement of COPD.

From pre-COPD to COPD: a Simple, Low cost and easy to IMplement (SLIM) risk calculator.

BACKGROUND: The lifetime risk of developing clinical COPD among smokers ranges from 13% to 22%. Identifying at-risk individuals who will develop overt disease in a reasonable timeframe may allow for early intervention. We hypothesised that readily available clinical and physiological variables could help identify ever-smokers at higher risk of developing chronic airflow limitation (CAL). METHODS: Among 2273 Lovelace Smokers' Cohort (LSC) participants, we included 677 (mean age 54 years) with normal spirometry at baseline and a minimum of three spirometries, each 1 year apart. Repeated spirometric measurements were used to determine incident CAL. Using logistic regression, demographics, anthropometrics, smoking history, modified Medical Research Council dyspnoea scale, St George's Respiratory Questionnaire, comorbidities and spirometry, we related variables obtained at baseline to incident CAL as defined by the Global Initiative for Chronic Obstructive Lung Disease and lower limit of normal criteria. The predictive model derived from the LSC was validated in subjects from the COPDGene study. RESULTS: Over 6.3 years, the incidence of CAL was 26 cases per 1000 person-years. The strongest independent predictors were forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) <0.75, having smoked ≥30 pack-years, body mass index (BMI) ≤25 kg·m2 and symptoms of chronic bronchitis. Having all four predictors increased the risk of developing CAL over 6 years to 85% (area under the receiver operating characteristic curve (AUC ROC) 0.84, 95% CI 0.81-0.89). The prediction model showed similar results when applied to subjects in the COPDGene study with a follow-up period of 10 years (AUC ROC 0.77, 95% CI 0.72-0.81). CONCLUSION: In middle-aged ever-smokers, a simple predictive model with FEV1/FVC, smoking history, BMI and chronic bronchitis helps identify subjects at high risk of developing CAL.

[Bronchoscopic COPD treatments]. / Traitements endoscopiques de la BPCO.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is associated with disabling respiratory symptoms including dyspnea, frequent exacerbations and chronic bronchitis. The currently available pharmacological and non-pharmacological therapies have limited efficacy, necessitating the development of interventional strategies, many of them endoscopic. STATE OF THE ART: Endoscopic lung volume reduction has markedly increased over recent years, principally as regards the endobronchial valves currently used in routine care. Indeed, multiple randomized trials have demonstrated a significant clinical benefit in a selected population identifiable due to the absence of interlobar collateral ventilation. Other endoscopic volume reduction techniques (polymers, thermal vapor, spirals) shall require additional studies before being considered as options in routine care. Targeted lung denervation (TLD) has aroused interest as a means of reducing exacerbations in the early phases of relevant studies. Endobronchial techniques (bronchoscopic cryospray, bronchial rheoplasty) are still at a very early stage of development, which is aimed at reducing the symptoms of chronic bronchitis. OUTLOOK: Aside from endobronchial valves, which are currently employed in routine care, all the above-mentioned endoscopic techniques require additional studies in order to determine their benefit/risk balance and to identify the population that would benefit the most. CONCLUSIONS: Endoscopic treatments constitute a major avenue of research and innovation in the therapeutic management of COPD. Inclusion of patients in disease registries and clinical trials remains essential, the objective being to gauge the interest of these treatments and their future role in everyday COPD management.

Assessing the genetic relationship between gastroesophageal reflux disease and chronic respiratory diseases: a mendelian randomization study.

BACKGROUND: Previous observational studies have found an association between gastroesophageal reflux disease (GERD) and chronic respiratory diseases, but it remains uncertain whether GERD causally influences these diseases. In this study, we aimed to estimate the causal associations between GERD and 5 chronic respiratory diseases. METHODS: 88 GERD-associated single nucleotide polymorphisms (SNPs) identified by the latest genome-wide association study were included as instrumental variables. Individual-level genetic summary data of participants were obtained from corresponding studies and the FinnGen consortium. We applied the inverse-variance weighted method to estimate the causality between genetically predicted GERD and 5 chronic respiratory diseases. Furthermore, the associations between GERD and common risk factors were investigated, and mediation analyses were conducted using multivariable MR. Various sensitivity analyses were also performed to verify the robustness of the findings. RESULTS: Our study demonstrated that genetically predicted GERD was causally associated with an increased risk of asthma (OR 1.39, 95%CI 1.25-1.56, P < 0.001), idiopathic pulmonary fibrosis (IPF) (OR 1.43, 95%CI 1.05-1.95, P = 0.022), chronic obstructive disease (COPD) (OR 1.64, 95%CI 1.41-1.93, P < 0.001), chronic bronchitis (OR 1.77, 95%CI 1.15-2.74, P = 0.009), while no correlation was observed for bronchiectasis (OR 0.93, 95%CI 0.68-1.27, P = 0.645). Additionally, GERD was associated with 12 common risk factors for chronic respiratory diseases. Nevertheless, no significant mediators were discovered. CONCLUSIONS: Our study suggested that GERD was a causal factor in the development of asthma, IPF, COPD and chronic bronchitis, indicating that GERD-associated micro-aspiration of gastric contents process might play a role in the development of pulmonary fibrosis in these diseases.

Prevalence and risk factors of patients with chronic bronchitis among Iraqi adults.

This study aimed to identify the risk factors associated with chronic bronchitis among patients seeking medical attention for respiratory conditions in Al-Najaf Al-Ashraf city, Iraq. The study employed a case-control design and recruited 134 participants using convenient sampling. Data was collected using a questionnaire consisting of four parts which included demographic characteristics, individual factors, family history, and seasonal, environmental, and nutritional factors. The majority of participants were males aged between 21 and 35 years, with 71.8% of the study group residing in rural areas and 66.3% of the control group living in urban areas. We found that asthma was the most prevalent associated disease among chronic bronchitis patients, with 64.1% reporting it. The risk factors associated with chronic bronchitis were residency, smoking, exposure to secondhand smoke, respiratory sensitivity, dust sensitivity, spring sensitivity, hay fever, asthma, pulmonary obstruction, pneumonia, pertussis, and family history. The study highlights the need for smoking cessation, physical fitness, and healthy eating habits to prevent chronic bronchitis. The findings of this study are important for healthcare professionals in Iraq to design and implement effective prevention and management strategies for chronic bronchitis.

Change in health outcomes for First Nations children with chronic wet cough: rationale and study protocol for a multi-centre implementation science study.

BACKGROUND: In children, chronic wet cough may be a sign of underlying lung disease, including protracted bacterial bronchitis (PBB) and bronchiectasis. Chronic (> 4 weeks in duration) wet cough (without indicators pointing to alternative causes) that responds to antibiotic treatment is diagnostic of PBB. Timely recognition and management of PBB can prevent disease progression to irreversible bronchiectasis with lifelong consequences. However, detection and management require timely health-seeking by carers and effective management by clinicians. We aim to improve (a) carer health-seeking for chronic wet cough in their child and (b) management of chronic wet cough in children by clinicians. We hypothesise that implementing a culturally integrated program, which is informed by barriers and facilitators identified by carers and health practitioners, will result in improved lung health of First Nations children, and in the future, a reduced the burden of bronchiectasis through the prevention of the progression of protracted bacterial bronchitis to bronchiectasis. METHODS: This study is a multi-centre, pseudorandomised, stepped wedge design. The intervention is the implementation of a program. The program has two components: a knowledge dissemination component and an implementation component. The implementation is adapted to each study site using a combined Aboriginal Participatory Action Research and an Implementation Science approach, guided by the Consolidated Framework of Implementation Research. There are three categories of outcome measures related to (i) health (ii) cost, and (iii) implementation. We will measure health-seeking as the proportion of parents seeking help for their child in a 6-month period before the intervention and the same 6-month period (i.e., the same six calendar months) thereafter. The parent-proxy, Cough-specific Quality of Life (PC-QoL) will be the primary health-related outcome measure. DISCUSSION: We hypothesise that a tailored intervention at each site will result in improved health-seeking for carers of children with a chronic wet cough and improved clinician management of chronic wet cough. In addition, we expect this will result in improved lung health outcomes for children with a chronic wet cough. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry; ACTRN12622000430730 , registered 16 March 2022, Retrospectively registered.

The expression of selected fibrotic factors in COPD and asthma.

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) and asthma are associated with chronic inflammation leading to airway obstruction and remodelling. There is little information on possible differences in the TGFB signalling pathway in the pathologies compared to less severe chronic bronchitis without airway obstruction. AIM: To assess the expression of the selected TGFB signalling pathway-associated genes in the pathologies. METHOD: RT-PCR was used to quantify the mRNAs in bronchoalveolar cells obtained from the Czech patients with chronic bronchitis (n = 26), COPD (n = 22), asthmatic (n = 14) patients. RESULTS: There was no difference in the BAL cell expression of TGFB1-3, TGFBR1-2, SMAD2,4,5, and 7 between our patients with COPD and those with chronic bronchitis. The expressions were also similar in the patients with asthma and chronic bronchitis. There was no difference between the patients with asthma and COPD. CONCLUSION: Although we observed no differences in our patients, other studies should investigate the genes and their possible correlation with advanced airway obstruction and emphysematous changes (Tab. 2, Fig. 3, Ref. 27). Text in PDF www.elis.sk Keywords: TGFB signalling pathway, COPD, asthma, chronic bronchitis, bronchoalveolar lavage.

Prevalence and subtyping of biofilms present in bronchoalveolar lavage from children with protracted bacterial bronchitis or non-cystic fibrosis bronchiectasis: a cross-sectional study.

BACKGROUND: Lower airway biofilms are hypothesised to contribute to poor treatment outcomes among children with chronic lung disease; however, data are scarce. We aimed to determine the presence and prevalence of biofilm in bronchoalveolar lavage from children with protracted bacterial bronchitis (PBB) or bronchiectasis; whether biofilm was associated with signs of lower airway infection; and whether biofilms were consistent with an upper or lower airway origin. METHODS: In this cross-sectional study, fluorescent microscopy techniques were used to detect biofilm in archived bronchoalveolar lavage specimens from a paediatric cohort (age <18 years) with PBB or bronchiectasis who were prospectively recruited to observational studies of chronic cough at Royal Children's Hospital (Brisbane, Australia) or Royal Darwin Hospital (Darwin, Australia). Children with cystic fibrosis were excluded. Lower airway infection was defined as bronchoalveolar lavage neutrophil percentage of 15% or more, or a culture of a bacterial pathogen at 104 colony-forming units per mL or more, or both. Biofilms were subtyped as either of lower airway origin (unrelated to squamous epithelial cells) or of upper airway origin (observed in close association with squamous epithelial cells). Bronchoalveolar lavages were considered contaminated with upper airway secretions if the squamous cell proportion was more than ten cells per 1000 nucleated cells (>1%). Primary outcomes were the prevalence of each biofilm subtype among children with PBB compared with children with bronchiectasis. Secondary outcomes were the prevalence of each biofilm subtype among children with signs of lower airway infection compared to children without. FINDINGS: Biofilm testing was performed on 144 bronchoalveolar lavage specimens collected between Jan 1, 2011, and Dec 16, 2014, and preserved at -80°C before biofilm testing (69 children with PBB from Brisbane and 75 children with bronchiectasis from Darwin). The prevalence of lower airway biofilms (unrelated to squamous epithelial cells) was similar among the children with PBB (25 [36%] of 69) and children with bronchiectasis (31 [41%] of 75; odds ratio [OR] 1·24, 95% CI 0·63-2·43), but higher among children with signs of lower airway infection (46 [48%] of 95) than children without (eight [19%] of 43; OR 4·11, 95% CI 1·73-9·78), irrespective of the underlying diagnosis. By contrast, upper airway biofilms (associated with squamous epithelial cells) were more prevalent among children with bronchiectasis (32 [43%] of 75) than children with PBB (16 [23%] of 69; OR 2·47, 95% CI 1·20-5·08) and were unrelated to lower airway infection. Upper airway contamination was uncommon (eight [11%] of 71) and was not evident in 23 (79%) of 29 bronchoalveolar lavages that were positive for upper airway biofilms. INTERPRETATION: Lower airway biofilms are prevalent, but not ubiquitous, in bronchoalveolar lavage from children with PBB or bronchiectasis, suggesting anti-biofilm therapies might be beneficial for some children. Detection of upper airway biofilms in bronchoalveolar lavage that did not have signs of contamination suggests that microaspiration might be important in some children. Specimen quality measures are recommended for future studies to account for the presence of upper airway biofilms. FUNDING: Financial Markets for Children Project Grant, National Health and Medical Research Council of Australia, Rebecca L Cooper Medical Research Foundation, Queensland Children's Hospital Foundation, and BrightSpark Foundation.

Comparison of clinical characteristics between chronic bronchitis and non-chronic bronchitis in patients with chronic obstructive pulmonary disease.

BACKGROUND: Chronic bronchitis (CB) is associated with poor outcomes in patients with chronic obstructive pulmonary disease. The aim of this study was to identify the characteristics that distinguish chronic bronchitis (CB) from non-CB. In addition, the features of mild CB versus severe CB were compared and a cut-off level was defined according to CAT1 and CAT2 scores. METHODS: This study was based on the Korea COPD Subgroup Study (KOCOSS) database, constructed in a multicenter COPD cohort study that recruited patients from 54 centers. CB was defined as CAT1 and CAT2 scores ≥ 3; severe CB was defined as CAT1 and CAT2 scores ≥ 4, while mild CB was defined as either a CAT1 or a CAT2 score < 4. Baseline characteristics, 1-year exacerbation rate, and 3-year FEV1 decline were compared in non-CB versus CB patients and in patients with mild CB versus severe CB. RESULTS: Among the 2162 patients enrolled in this study, 497 (23%) had CB. These patients were more likely than non-CB patients to be current smokers; they also had higher symptom and depression/anxiety scores. Lung function tests showed lower FEV1, FEV1/FVC, and DLco values in CB patients. Among CB patients, 67.6% had mild disease. Symptom and depression/anxiety scores were worse in patients with severe CB than in patients with mild CB. There were no significant differences in the lung function tests of the two groups. Analysis of 1-year exacerbation rates in CB patients and non-CB patients revealed that patients with CB more frequently had moderate-to-severe exacerbations (OR = 1.46, p < 0.01). More severe exacerbation was also present in patients with severe CB than in patients with mild CB (OR = 2.52, p = 0.01). The difference in annual FEV1 decline rate did not significantly differ either between CB patients and non-CB patients or between patients with severe CB and patients with mild CB. CONCLUSIONS: CB patients had worse symptoms and lung function than non-CB patients; CB patients also had more frequent moderate-to-severe exacerbation. Patients with severe CB had higher symptom scores and more frequent severe exacerbation than did patients with mild CB.

Long-Term Risk of Mortality Associated with Isolation of Pseudomonas aeruginosa in COPD: A Systematic Review and Meta-Analysis.

BACKGROUND: Chronic bronchial infection is frequent in chronic obstructive pulmonary disease (COPD), but the impact of the isolation of pathogenic bacteria, and in particular Pseudomonas aeruginosa (PA) in respiratory samples on the prognosis of COPD is unclear. METHODS: We conducted a systematic review of prognostic studies including patients with isolation of PA in sputum in stable state or during exacerbations of COPD. The main outcomes were all-cause mortality, respiratory mortality, and number and severity of future exacerbations. Data were expressed as hazard ratio (HR) (95% confidence interval [CI]) whenever possible. RESULTS: Of 2773 studies, eight were finally included (23,228 individuals). The mean age ranged from 65.5 to 73 years. Six studies reported data for all-cause mortality. The adjusted risk of death was almost double in patients with PA isolation (HR 1.95, 95% CI, 1.34 to 2.84; quality of evidence moderate). Patients with PA isolation showed a three times higher adjusted risk of readmission at 30 days after discharge (OR 3.60, 95% CI, 3.60 to 12.03, 1 study; quality of evidence very low), and more than double adjusted risk of death and hospitalization at two years (HR 2.80, 95% CI, 2.20 to 3.56, 1 study; quality of evidence very low). CONCLUSION: There is moderate certainty that the isolation of PA in sputum is associated with an adjusted increased risk of death in patients with COPD.

C FTR variants are associated with chronic bronchitis in smokers.

INTRODUCTION: Loss-of-function variants in both copies of the cystic fibrosis transmembrane conductance regulator (CFTR) gene cause cystic fibrosis (CF); however, there is evidence that reduction in CFTR function due to the presence of one deleterious variant can have clinical consequences. Here, we hypothesise that CFTR variants in individuals with a history of smoking are associated with chronic obstructive pulmonary disease (COPD) and related phenotypes. METHODS: Whole-genome sequencing was performed through the National Heart, Lung, and Blood Institute TOPMed (TransOmics in Precision Medicine) programme in 8597 subjects from the COPDGene (Genetic Epidemiology of COPD) study, an observational study of current and former smokers. We extracted clinically annotated CFTR variants and performed single-variant and variant-set testing for COPD and related phenotypes. Replication was performed in 2118 subjects from the ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) study. RESULTS: We identified 301 coding variants within the CFTR gene boundary: 147 of these have been reported in individuals with CF, including 36 CF-causing variants. We found that CF-causing variants were associated with chronic bronchitis in variant-set testing in COPDGene (one-sided p=0.0025; OR 1.53) and in meta-analysis of COPDGene and ECLIPSE (one-sided p=0.0060; OR 1.52). Single-variant testing revealed that the F508del variant was associated with chronic bronchitis in COPDGene (one-sided p=0.015; OR 1.47). In addition, we identified 32 subjects with two or more CFTR variants on separate alleles and these subjects were enriched for COPD cases (p=0.010). CONCLUSIONS: Cigarette smokers who carry one deleterious CFTR variant have higher rates of chronic bronchitis, while presence of two CFTR variants may be associated with COPD. These results indicate that genetically mediated reduction in CFTR function contributes to COPD related phenotypes, in particular chronic bronchitis.

Protocol for CLASSIC PBB: comparison of lower airway sampling strategies in children with protracted bacterial bronchitis.

BACKGROUND: Protracted bacterial bronchitis (PBB) is an endobronchial infection and a the most common cause of chronic wet cough in young children. It is treated with antibiotics, which can only be targeted if the causative organism is known. As most affected children do not expectorate sputum, lower airway samples can only be obtained by bronchoalveolar lavage (BAL) samples taken during flexible bronchoscopy (FB-BAL). This is invasive and is therefore reserved for children with severe or relapsing cases. Most children with PBB are treated empirically with broad spectrum antibiotics. CLASSIC PBB will compare the pathogen yield from two less invasive strategies with that from FB-BAL to see if they are comparable. METHODS: 131 children with PBB from four UK centres referred FB-BAL will be recruited. When attending for FB-BAL, they will have a cough swab and an induced sputum sample obtained. The primary outcome will be the discordance of the pathogen yield from the cough swab and the induced sputum when compared with FB-BAL. Secondary outcomes will be the sensitivity of each sampling strategy, the success rate of the induced sputum in producing a usable sample and the tolerability of each of the three sampling strategies. DISCUSSION: If either or both of the two less invasive airway sampling strategies are shown to be a useful alternative to FB-BAL, this will lead to more children with PBB having lower airway samples enabling targeted antibiotic prescribing. It would also reduce the need for FB, which is known to be burdensome for children and their families. TRIAL REGISTRATION NUMBER: ISRCTN79883982.

COPD patients with chronic bronchitis and higher sputum eosinophil counts show increased type-2 and PDE4 gene expression in sputum.

Chronic obstructive pulmonary disease (COPD) patients with higher eosinophil counts are associated with increased clinical response to phosphodiesterase-4-inhibitors (PDE4i). However, the underlying inflammatory mechanisms associated with this increased response is not yet elucidated. This post hoc analysis focused on sputum gene expression in patients with chronic bronchitis who underwent 32-day treatment with two doses of the inhaled PDE4i CHF6001 (tanimilast) or placebo on top of triple therapy. Biological characterization and treatment effects were assessed between patients with different sputum eosinophil levels (eosinophilhigh  ≥ 3%; eosinophillow  < 3%) at baseline (primary samples) or at the end of the treatment of the placebo arm (validation samples). Forty-one genes were differentially expressed in primary samples (p-adjusted for false discovery rate < 0.05); all up-regulated in eosinophilhigh patients and functionally enriched for type-2 and PDE4 inflammatory processes. Eleven out of nineteen genes having immune system biological processes annotations including IL5RA, ALOX15, IL1RL1, CLC, GATA1 and PDE4D were replicated using validation samples. The expression of a number of these inflammatory mediators was reduced by tanimilast treatment, with greater effects observed in eosinophilhigh patients. These findings suggest that type-2 and PDE4 overexpression in COPD patients with higher sputum eosinophil counts contribute to the differential clinical response to PDE4i observed in previous clinical trials.

Chronic Cough Due to Stable Chronic Bronchitis: CHEST Expert Panel Report.

BACKGROUND: Chronic cough due to chronic bronchitis (CB) causes significant impairment in quality of life, and effective treatment strategies are needed. We conducted a systematic review on the management of chronic cough due to CB to update the recommendations and suggestions of the American College of Chest Physicians (CHEST) 2006 guideline on this topic. METHODS: This systematic review asked three questions: (1) What are the clinical features of the history that suggest a patient's cough-phlegm syndrome is due to CB? (2) Can treatment of stable CB improve or eliminate chronic cough? (3) Can therapy that targets chronic cough due to CB prevent or reduce the occurrence of acute CB exacerbations? Studies of adult patients with CB were included and assessed for relevance and quality. Based on the systematic review, guideline suggestions were developed and voted on by using the CHEST organization methodology. RESULTS: The search strategy used an assortment of descriptors and assessments to identify studies of chronic cough due to CB. CONCLUSIONS: The evidence supporting the management of chronic cough due to CB is limited overall and of low quality. This article provides guidance on treatment by presenting suggestions based on the best currently available evidence and identifies gaps in our knowledge and areas for future research.

Chronic bronchitis without airflow obstruction, asthma and rhinitis are differently associated with cardiovascular risk factors and diseases.

BACKGROUND AND OBJECTIVES: Cardiovascular and respiratory diseases can frequently coexist. Understanding their link may improve disease management. We aimed at assessing the associations of chronic bronchitis (CB), asthma and rhinitis with cardiovascular diseases and risk factors in the general population. METHODS: We used data collected in the Gene Environment Interactions in Respiratory Diseases study, an Italian multicentre, multicase-control study. Among 2463 participants (age 21-86, female 50%) who underwent standardized interviews, skin prick and lung function tests, we identified 254 cases of CB without airflow obstruction, 418 cases of asthma without CB, 959 cases of rhinitis alone, and 832 controls. The associations of respiratory diseases with reported cardiovascular risk factors (lifestyles, hypertension, dyslipidaemia), heart disorders (myocardial infarction, coronary thrombosis, angina, aorta or heart surgery) and intermittent claudication were estimated through relative risk ratios (RRR) by multinomial logistic regression models. RESULTS: Compared to controls, CB cases were more likely to be heavy smokers, alcohol consumers, physically inactive, and to suffer from hypertension or dyslipidaemia; rhinitis cases were less obese but more likely to have hypertension. Asthma was significantly associated with current smoking. After adjusting for cardiovascular risk factors, heart disorders were associated with CB (RRR[95%CI]: 1.58[1.12-2.22]) and rhinitis (1.35[0.98-1.85]) and intermittent claudication was associated with CB (3.43[2.52-4.67]), asthma (1.51[1.04-2.21]) and rhinitis (2.03[1.34-3.07]). CONCLUSIONS: CB, asthma and rhinitis were associated with cardiovascular risk factors and diseases. In particular, CB shared with cardiovascular diseases almost all risk factors and was strongly associated with a higher risk of heart disorders and intermittent claudication.

The St. George's Respiratory Questionnaire Definition of Chronic Bronchitis May Be a Better Predictor of COPD Exacerbations Compared With the Classic Definition.

BACKGROUND: Chronic bronchitis (CB) increases risk of COPD exacerbations. We have shown that the St. George's Respiratory Questionnaire (SGRQ) CB definition identifies patients with a similar clinical phenotype as classically defined CB. Whether the SGRQ CB definition is a predictor of future COPD exacerbations is unknown. METHODS: We analyzed 7,557 smokers with normal spirometry and Global Initiative for Chronic Obstructive Lung Disease stage 1-4 COPD in the Genetic Epidemiology of COPD study with longitudinal follow-up data on exacerbations. Subjects were divided into classic CB+ or classic CB-, using the classic definition. In addition, subjects were divided into SGRQ CB+ or SGRQ CB-. Exacerbation frequency and severe exacerbation frequency were determined in each group. Multivariable linear regressions were performed for exacerbation frequency with either classic CB or SGRQ CB and relevant covariates. RESULTS: There were 1,434 classic CB+ subjects and 2,290 SGRQ CB+ subjects. The classic CB+ group had a greater exacerbation frequency compared with the classic CB- group (0.69 ± 1.26 vs 0.36 ± 0.90 exacerbations per patient per year; P < .0001) and a greater severe exacerbation frequency (0.26 ± 0.74 vs 0.13 ± 0.46 severe exacerbations per patient per year; P < .0001). There were similar differences between the SGRQ CB+ and SGRQ CB- groups. In multivariable analysis, both SGRQ CB and classic CB were independent predictors of exacerbation frequency, but SGRQ CB had a higher regression coefficient. In addition, SGRQ CB was an independent predictor of severe exacerbation frequency whereas classic CB was not. CONCLUSIONS: The SGRQ CB definition identified more subjects at risk for future exacerbations than the classic CB definition. SGRQ CB was at least a similar if not better predictor of future exacerbations than classic CB.

Risk factors for lung cancer in COPD - results from the Bergen COPD cohort study.

BACKGROUND: COPD patients have an increased risk of developing lung cancer, but the underlying mechanisms are poorly understood. We aimed to identify risk factors for lung cancer in patients from the Bergen COPD Cohort Study. METHODS: We compared 433 COPD patients with 279 healthy controls, all former or current smokers. All COPD patients had FEV1<80% and FEV1/FVC-ratio<0.7. Baseline predictors were sex, age, spirometry, body composition, smoking history, emphysema assessed by CT, chronic bronchitis, prior exacerbation frequency, Charlson Comorbidity Score, inhalation medication and 44 serum/plasma inflammatory biomarkers. Patients were followed up for 9 years recording incidence of lung cancer. Cox-regression models were fitted for the statistical analyses. The biomarkers were evaluated using principal component analysis. RESULTS: 28 COPD patients and 3 controls developed lung cancer, COPD patients had a significantly higher risk of developing lung cancer, (HR 5.0; 95% CI 1.5-17.1, p < 0.01, adjusted values). Among COPD patients, emphysema (HR 4.4; 1.7-10.8, p < 0.01) and obesity (HR 3.3; 1.3-8.5, p = 0.02) were associated with a higher cancer rate. Use of inhaled steroids was associated with a lower rate (HR 0.4; 0.2-0.9, p = 0.03). Smoking status, pack-years smoked or levels of systemic inflammatory markers, except for interferon gamma-induced protein 10, did not affect the lung cancer rate in patients with COPD. CONCLUSION: Patients with COPD have a higher lung cancer rate compared to healthy controls adjusted for smoking. The presence of emphysema and obesity in COPD predicted a higher lung cancer risk in COPD patients. Systemic inflammation was not associated with increased lung cancer risk.

Occupational exposures and incidence of chronic bronchitis and related symptoms over two decades: the European Community Respiratory Health Survey.

OBJECTIVES: Chronic bronchitis (CB) is an important chronic obstructive pulmonary disease (COPD)-related phenotype, with distinct clinical features and prognostic implications. Occupational exposures have been previously associated with increased risk of CB but few studies have examined this association prospectively using objective exposure assessment. We examined the effect of occupational exposures on CB incidence in the European Community Respiratory Health Survey. METHODS: Population samples aged 20-44 were randomly selected in 1991-1993, and followed up twice over 20 years. Participants without chronic cough or phlegm at baseline were analysed. Coded job histories during follow-up were linked to the ALOHA Job Exposure Matrix, generating occupational exposure estimates to 12 categories of chemical agents. Their association with CB incidence over both follow-ups was examined with Poisson models using generalised estimating equations. RESULTS: 8794 participants fulfilled the inclusion criteria, contributing 13 185 observations. Only participants exposed to metals had a higher incidence of CB (relative risk (RR) 1.70, 95% CI 1.16 to 2.50) compared with non-exposed to metals. Mineral dust exposure increased the incidence of chronic phlegm (RR 1.72, 95% CI 1.43 to 2.06). Incidence of chronic phlegm was increased in men exposed to gases/fumes and to solvents and in women exposed to pesticides. CONCLUSIONS: Occupational exposures are associated with chronic phlegm and CB, and the evidence is strongest for metals and mineral dust exposure. The observed differences between men and women warrant further investigation.

Chronic bronchitis: High prevalence in never smokers and underdiagnosis- A population-based study in Colombia.

The objective of the article was to establish the prevalence, underdiagnosis, and risk factors of chronic bronchitis (CB) in a general population in five Colombian cities. Cross-sectional study using a probabilistic sampling technique in five Colombian cities was adopted. The CB definition was "cough and expectoration for three or more months per year for at least two consecutive years." Underdiagnosis was considered in subjects with clinical definition without previous medical diagnosis. Univariate χ2 or Student's t-test and logistic regression analysis were used. The study included 5539 subjects. The prevalence was 5.5%, the underdiagnosis 50.3%, and 33.7% of the cases were in nonsmokers (53.6% in women vs. 16.9% in men, p < 0.001). The adjusted risk factors were living in Bogota, current smoking, male, age ≥ 64 years, low education, indoor wood smoke exposure, and occupational exposure to vapors, gases, dust, and fumes. CB is a common disease among adults in Colombia. The underdiagnosis was high and there were a large proportion of cases in nonsmokers, particularly in women. Our findings support the association of CB with indoor wood smoke and occupational exposures.