Airway obstruction in never smokers: results from the Third National Health and Nutrition Examination Survey

Seasonal effect of PM2.5 exposure in patients with COPD: a multicentre panel study

Background: Exposure to particulate matter <2.5 μm (PM2.5) is linked to chronic obstructive pulmonary disease (COPD), but most studies lack individual PM2.5 measurements. Seasonal variation and their impact on clinical outcomes remain understudied. Objective: This study investigated the impact of PM2.5 concentrations on COPD-related clinical outcomes and their seasonal changes. Methods: A multicentre panel study enrolled 105 COPD patients (age range: 46-82) from July 2019 to August 2020. Their mean forced expiratory volume in 1 second after bronchodilation was 53.9%. Individual PM2.5 levels were monitored continuously with indoor measurements at residences and outdoor data from the National Ambient Air Quality Monitoring Information System. Clinical parameters, including pulmonary function tests, symptom questionnaires (CAT and SGRQ-C), and impulse oscillometry (IOS), were assessed every three months over the course of one year. Statistical analysis was conducted using a linear mixed-effect model to account for repeated measurements and control for confounding variables, including age, sex, smoking status and socioeconomic status. Results: The mean indoor and outdoor PM2.5 concentrations were 16.2 ± 8.4 μg m-3 and 17.2 ± 5.0 μg m-3, respectively. Winter had the highest PM2.5 concentrations (indoor, 18.8 ± 11.7 μg m3; outdoor, 22.5 ± 5.0 μg m-3). Higher PM2.5 concentrations significantly correlated with poorer St. George's Respiratory Questionnaire for COPD (SGRQ-C) scores and increased acute exacerbations, particularly in winter. Patients of lower socioeconomic status were more vulnerable. Increased PM2.5 concentrations were also associated with amplified small airway resistance (R5-R20). Conclusions: PM2.5 concentration changes are positively correlated with poorer SGRQ-C scores and increased acute exacerbations in COPD patients with significant seasonal variations, especially in winter.

Gender, tobacco and chronic obstructive pulmonary disease: analysis of the 2020 National Health Interview Survey

RATIONALE

Recent studies describe an increasing prevalence of chronic obstructive pulmonary disease (COPD) and higher COPD exacerbation rates among women compared with men despite lower average cigarette use, which has raised the question of whether women are more susceptible to the effects of tobacco smoke. We examined associations between gender, cigarette smoking and COPD in a national dataset.

METHODS

We used cross-sectional data for US respondents aged ≥40 years from the 2020 National Health Interview Survey (NHIS). Weighted multivariable logistic regressions assessed the relationship between gender and respondent-reported physician-diagnosed COPD, adjusting for tobacco use and sociodemographic covariates. Additional analyses were performed to determine if the relationship between cigarette smoking and COPD was modified by gender.

RESULTS

Women had a higher COPD prevalence (7.8%) than men (6.5%) despite lower cigarette smoke exposure. Women were less likely to have ever smoked, and among respondents who had smoked, women had a lower average pack-year history compared with men. In multivariable regressions, female gender was associated with a higher risk of COPD (adjusted risk ratio 1.47, 95% CI 1.30 to 1.65) and the relative risk was similar for respondents both with and without a history of smoking. Moreover, there was no significant interaction between gender and smoking status or gender and pack-year exposure relating to COPD prevalence.

CONCLUSIONS

Among adults aged ≥40 years, women had a roughly 50% greater risk of COPD than men. Higher susceptibility to cigarette smoking in women did not explain the difference.

The association between Planetary Health Diet Index (PHDI) and chronic obstructive pulmonary disease (COPD): the mediating role of dietary inflammatory index (DII)

BACKGROUND

Given global changes in the environment and dietary habits, it is critical to understand the potential impact of dietary factors and dietary inflammation on respiratory diseases, including COPD. Studying these relationships can help develop more effective prevention strategies. PHDI is a dietary scoring system designed to balance human health and environmental sustainability by promoting increased consumption of plant-based foods and reduced intake of red meat, sugar, and highly processed foods. In contrast, DII quantifies the inflammatory potential of a diet. This study examines the association between PHDI and COPD and assesses whether DII mediates this relationship.

METHODS

We used subgroup analysis, smooth curve fitting, and multivariable logistic regression to investigate the connection between PHDI and the occurrence of COPD. Furthermore, a mediation analysis was carried out to investigate any possible correlation between DII and the link between PHDI and COPD.

RESULTS

30,304 participants were included in this investigation, and 1,498 of them reported COPD events. For every 10-point increase in PHDI and each unit increase in DII was associated with a 9% reduction (OR = 0.91, 95% CI: 0.86, 0.97) and an 8% increase (OR = 1.08, 95% CI: 1.02, 1.13) in the prevalence of COPD, respectively, when all variables were adjusted for using multivariable logistic regression. Additionally, the results remain robust when PHDI and DII are converted to tertile. An investigation of smooth curve fitting showed a linear correlation between the risk of COPD and PHDI. The results of the mediation analysis showed that 17.95% of the relationship between PHDI and COPD was mediated by DII (p = 0.034).

CONCLUSIONS

Higher PHDI levels are associated with a lower prevalence of COPD. Additionally, DII appears to mediate this relationship, suggesting that an anti-inflammatory diet may provide benefits.

Differential Inflammatory Cytokine Elaboration in Serum from Brick Kiln Workers in Bhaktapur, Nepal

Previous studies involving workers at brick kilns in the Kathmandu Valley of Nepal have investigated chronic exposure to hazardous levels of fine particulate matter (PM2.5) common in ambient and occupational environments. Such exposures are known to cause and/or exacerbate chronic respiratory diseases, including chronic obstructive pulmonary disease (COPD) and asthma. However, there is a paucity of data regarding the status of systemic inflammation observed in exposed workers at brick manufacturing facilities within the country. In the current study, we sought to elucidate systemic inflammatory responses by quantifying the molecular cytokine/chemokine profiles in serum from the study participants. A sample of participants were screened from a kiln in Bhaktapur, Nepal (n = 32; 53% female; mean ± standard deviation: 28.42 ± 11.47 years old) and grouped according to job category. Blood was procured from participants on-site, allowed to clot at room temperature, and centrifuged to obtain total serum. A human cytokine antibody array was used to screen the inflammatory mediators in serum samples from each of the participants. For the current study, four job categories were evaluated with n = 8 for each. Comparisons were generated between a control group of administration workers vs. fire master workers, administration workers vs. green brick hand molders, and administration workers vs. top loaders. We discovered significantly increased concentrations of eotaxin-1, eotaxin-2, GCSF, GM-CSF, IFN-γ, IL-1α, IL-1β, IL-6, IL-8, TGF-β1, TNF-α, and TIMP-2 in serum samples from fire master workers vs. administration workers (p < 0.05). Each of these molecules was also significantly elevated in serum from green brick hand molders compared to administration workers (p < 0.05). Further, each molecule in the inflammatory screening with the exception of TIMP-2 was significantly elevated in serum from top loaders compared to administration workers (p < 0.05). With few exceptions, the fire master workers expressed significantly more systemic inflammatory molecular abundance when compared to all other job categories. These results reveal an association between pulmonary exposure to PM2.5 and systemic inflammatory responses likely mediated by cytokine/chemokine elaboration. The additional characterization of a broader array of inflammatory molecules may provide valuable insight into the susceptibility to lung diseases among this population.

The prevalence and mortality risks of PRISm and COPD in the United States from NHANES 2007-2012

BACKGROUND

We estimated the prevalence and mortality risks of preserved ratio impaired spirometry (PRISm) and chronic obstructive pulmonary disease (COPD) in the US adult population.

METHODS

We linked three waves of pre-bronchodilator spirometry data from the US National Health and Nutritional Examination Survey (2007-2012) with the National Death Index. The analytic sample included adults ages 20 to 79 without missing data on age, sex, height, BMI, race/ethnicity, and smoking status. We defined COPD (GOLD 1, 2, and 3-4) and PRISm using FEV1/FVC cut points by the Global Initiative for Chronic Obstructive Lung Disease (GOLD). We compared the prevalence of GOLD stages and PRISm by covariates across the three waves. We estimated adjusted all-cause and cause-specific mortality risks by COPD stage and PRISm using all three waves combined.

RESULTS

Prevalence of COPD and PRISm from 2007-2012 ranged from 13.1%-14.3% and 9.6%-10.2%, respectively. We found significant differences in prevalence by sex, age, smoking status, and race/ethnicity. Males had higher rates of COPD regardless of stage, while females had higher rates of PRISm. COPD prevalence increased with age, but not PRISm, which was highest among middle-aged individuals. Compared to current and never smokers, former smokers showed lower rates of PRISm but higher rates of GOLD 1. COPD prevalence was highest among non-Hispanic White individuals, and PRISm was notably higher among non-Hispanic Black individuals (range 31.4%-37.4%). We found associations between PRISm and all-cause mortality (hazard ratio [HR]: 2.3 95% CI: 1.9-2.9) and various cause-specific deaths (HR ranges: 2.0-5.3). We also found associations between GOLD 2 (HR: 2.1, 95% CI: 1.7-2.6) or higher (HR: 4.2, 95% CI: 2.7-6.5) and all-cause mortality. Cause-specific mortality risk varied within COPD stages but typically increased with higher GOLD stage.

CONCLUSIONS

The prevalence of COPD and PRISm remained stable from 2007-2012. Greater attention should be paid to the potential impacts of PRISm due to its higher prevalence in minority groups and its associations with mortality across various causes including cancer.

Availability of Receptors for Advanced Glycation End-Products (RAGE) Influences Differential Transcriptome Expression in Lungs from Mice Exposed to Chronic Secondhand Smoke (SHS)

The receptor for advanced glycation end-products (RAGE) has a central function in orchestrating inflammatory responses in multiple disease states including chronic obstructive pulmonary disease (COPD). RAGE is a transmembrane pattern recognition receptor with particular interest in lung disease due to its naturally abundant pulmonary expression. Our previous research demonstrated an inflammatory role for RAGE following acute exposure to secondhand smoke (SHS). However, chronic inflammatory mechanisms associated with RAGE remain ambiguous. In this study, we assessed transcriptional outcomes in mice exposed to chronic SHS in the context of RAGE expression. RAGE knockout (RKO) and wild-type (WT) mice were delivered nose-only SHS via an exposure system for six months and compared to control mice exposed to room air (RA). We specifically compared WT + RA, WT + SHS, RKO + RA, and RKO + SHS. Analysis of gene expression data from WT + RA vs. WT + SHS showed FEZ1, Slpi, and Msln as significant at the three-month time point; while RKO + SHS vs. WT + SHS identified cytochrome p450 1a1 and Slc26a4 as significant at multiple time points; and the RKO + SHS vs. WT + RA revealed Tmem151A as significant at the three-month time point as well as Gprc5a and Dynlt1b as significant at the three- and six-month time points. Notable gene clusters were functionally analyzed and discovered to be specific to cytoskeletal elements, inflammatory signaling, lipogenesis, and ciliogenesis. We found gene ontologies (GO) demonstrated significant biological pathways differentially impacted by the presence of RAGE. We also observed evidence that the PI3K-Akt and NF-κB signaling pathways were significantly enriched in DEGs across multiple comparisons. These data collectively identify several opportunities to further dissect RAGE signaling in the context of SHS exposure and foreshadow possible therapeutic modalities.

COPD Exposed to Air Pollution: A Path to Understand and Protect a Susceptible Population

TOPIC IMPORTANCE

Air pollution poses a risk to the respiratory health of individuals with COPD. Long- and short-term exposures to higher levels of particulate-rich air pollution are associated with increased COPD exacerbation, hospitalization, and mortality, collectively implicating air pollution as a cause of adverse COPD-related outcomes.

REVIEW FINDINGS

This review summarizes the evidence for COPD as a phenotype that confers susceptibility for adverse health outcomes in the face of common air pollution. We highlight how typical contributors to compromised urban air quality, including that from traffic, wildfire smoke, and indoor biomass combustion, adversely affect the COPD patient population. Evidence underscoring the burden of ongoing air pollution exposure on patients with COPD is discussed. We then detail the detrimental impact of that exposure on COPD pathophysiology, which in turn increases the patient's susceptibility. We specifically propose that indoor air is a particularly rational target for increased monitoring and remediation to protect patients with COPD. Because COPD is a heterogeneous disease with several endotypes, future intervention studies need to better include control populations, to highlight COPD-specific risks and identify subpopulations within patients with COPD who will benefit the most from improved indoor air quality.

SUMMARY

Regulatory efforts must continue to broadly lower emission standards to protect this susceptible population from the negative health impacts of air pollution.

Sex-differences in COPD: from biological mechanisms to therapeutic considerations

Chronic obstructive pulmonary disease (COPD) is a heterogeneous respiratory condition characterized by symptoms of dyspnea, cough, and sputum production. We review sex-differences in disease mechanisms, structure-function-symptom relationships, responses to therapies, and clinical outcomes in COPD with a specific focus on dyspnea. Females with COPD experience greater dyspnea and higher morbidity compared to males. Imaging studies using chest computed tomography scans have demonstrated that females with COPD tend to have smaller airways than males as well as a lower burden of emphysema. Sex-differences in lung and airway structure lead to critical respiratory mechanical constraints during exercise at a lower absolute ventilation in females compared to males, which is largely explained by sex differences in maximum ventilatory capacity. Females experience similar benefit with respect to inhaled COPD therapies, pulmonary rehabilitation, and smoking cessation compared to males. Ongoing re-assessment of potential sex-differences in COPD may offer insights into the evolution of patterns of care and clinical outcomes in COPD patients over time.

Association between occupational exposure and chronic obstructive pulmonary disease and respiratory symptoms in the Spanish population

INTRODUCTION

The aim of this study was to analyze the impact of occupational exposure on chronic obstructive pulmonary disease (COPD) and respiratory symptoms in the general Spanish population.

METHODS

This was a study nested in the Spanish EPISCAN II cross-sectional epidemiological study that included participants who had completed a structured questionnaire on their occupational history, a questionnaire on respiratory symptoms, and forced spirometry. The data were analyzed using Chi-square and Student's t tests and adjusted models of multiple linear regression and logistic regression.

RESULTS

We studied 7502 subjects, 51.1% women, with a mean age of 60±11 years. Overall, 53.2% reported some respiratory symptoms, 7.9% had respiratory symptoms during their work activity, 54.2% were or had been smokers, and 11.3% (851 subjects) met COPD criteria on spirometry. A total of 3056 subjects (40.7%) reported exposure to vapors, gases, dust or fumes (VGDF); occupational exposure to VGDF was independently associated with the presence of COPD (OR 1.22, 95% CI: 1.03-1.44), respiratory symptoms (OR 1.45, 95%: CI 1.30-1.61), and respiratory symptoms at work (OR 4.69, 95% CI: 3.82-5.77), with a population attributable fraction for COPD of 8.2%.

CONCLUSIONS

Occupational exposure is associated with a higher risk of COPD and respiratory symptoms in the Spanish population. These results highlight the need to follow strict prevention measures to protect the respiratory health of workers.

Prediction and stratification of longitudinal risk for chronic obstructive pulmonary disease across smoking behaviors

Smoking is the leading risk factor for chronic obstructive pulmonary disease (COPD) worldwide, yet many people who never smoke develop COPD. We perform a longitudinal analysis of COPD in the UK Biobank to derive and validate the Socioeconomic and Environmental Risk Score which captures additive and cumulative environmental, behavioral, and socioeconomic exposure risks beyond tobacco smoking. The Socioeconomic and Environmental Risk Score is more predictive of COPD than smoking status and pack-years. Individuals in the highest decile of the risk score have a greater risk for incident COPD compared to the remaining population. Never smokers in the highest decile of exposure risk are more likely to develop COPD than previous and current smokers in the lowest decile. In general, the prediction accuracy of the Social and Environmental Risk Score is lower in non-European populations. While smoking status is often considered in screening COPD, our finding highlights the importance of other non-smoking environmental and socioeconomic variables.

Analyses of Factors Associated with Acute Exacerbations of Chronic Obstructive Pulmonary Disease: A Review

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is the exacerbation of a range of respiratory symptoms during the stable phase of chronic obstructive pulmonary disease (COPD). AECOPD is thus a dangerous stage and key event in the course of COPD, as its deterioration and frequency seriously affects the quality of life of patients and shortens their survival. Acute exacerbations occur and develop due to many factors such as infection, tobacco smoke inhalation, air pollution, comorbidities, airflow limitation, various biomarkers, history of previous deterioration, natural killer cell abnormalities, immunoglobulin G deficiency, genetics, abnormal muscle and nutritional status, negative psychology, and seasonal temperature changes. There is relatively limited research on the impact of the role of standardized management on the alleviation of AECOPD. However, with the establishment of relevant prevention and management systems and the promotion of artificial intelligence technology and Internet medical approaches, long-term effective and standardized management of COPD patients may help to achieve the quality of life and disease prognosis in COPD patients and reduce the risk of AE.

Inflammatory Cytokine Elaboration Following Secondhand Smoke (SHS) Exposure Is Mediated in Part by RAGE Signaling

The receptor for advanced glycation end products (RAGE) is a key contributor to immune and inflammatory responses in myriad diseases. RAGE is a transmembrane pattern recognition receptor with a special interest in pulmonary anomalies due to its naturally abundant pulmonary expression. Our previous studies demonstrated an inflammatory role for RAGE following acute 30-day exposure to secondhand smoke (SHS), wherein immune cell diapedesis and cytokine/chemokine secretion were accentuated in part via RAGE signaling. However, the chronic inflammatory mechanisms associated with RAGE have yet to be fully elucidated. In this study, we address the impact of long-term SHS exposure on RAGE signaling. RAGE knockout (RKO) and wild-type (WT) mice were exposed to SHS using a nose-only delivery system (Scireq Scientific, Montreal, Canada) for six months. SHS-exposed animals were compared to mice exposed to room air (RA) only. Immunoblotting was used to assess the phospho-AKT and phospho-ERK activation data, and colorimetric high-throughput assays were used to measure NF-kB. Ras activation was measured via ELISAs. Bronchoalveolar lavage fluid (BALF) cellularity was quantified, and a mouse cytokine antibody array was used to screen the secreted cytokines. The phospho-AKT level was decreased, while those of phospho-ERK, NF-kB, and Ras were elevated in both groups of SHS-exposed mice, with the RKO + SHS-exposed mice demonstrating significantly decreased levels of each intermediate compared to those of the WT + SHS-exposed mice. The BALF contained increased levels of diverse pro-inflammatory cytokines in the SHS-exposed WT mice, and diminished secretion was detected in the SHS-exposed RKO mice. These results validate the role for RAGE in the mediation of chronic pulmonary inflammatory responses and suggest ERK signaling as a likely pathway that perpetuates RAGE-dependent inflammation. Additional characterization of RAGE-mediated pulmonary responses to prolonged exposure will provide a valuable insight into the cellular mechanisms of lung diseases such as chronic obstructive pulmonary disease.

Association of Smoking and Respiratory Disease History with Pancreatic Pathologies Requiring Surgical Resection

BACKGROUND

The purpose of this study was to examine the relationship between various respiratory conditions, including hypercapnic respiratory disease, and a multitude of resected pancreatic lesions.

METHODS

This retrospective case-control study queried a prospectively maintained database of patients who underwent pancreaticoduodenectomy between January 2015 and October 2021. Patient data, including smoking history, medical history, and pathology reports, were recorded. Patients with no smoking history and no concomitant respiratory conditions were designated as the control group.

RESULTS

A total of 723 patients with complete clinical and pathological data were identified. Male current smokers showed increased rates of PDAC (OR 2.33, 95% CI 1.07-5.08, p = 0.039). Male patients with COPD had a markedly increased association with IPMN (OR 3.02, CI 1.08-8.41, p = 0.039), while females with obstructive sleep apnea had a four-fold increase in risk of IPMN compared to women in the control group (OR 3.89, CI 1.46-10.37, p = 0.009). Surprisingly, female patients with asthma had a decreased incidence of pancreatic and periampullary adenocarcinoma (OR 0.36, 95% CI 0.18-0.71. p < 0.01).

CONCLUSION

This large cohort study reveals possible links between respiratory pathologies and various pancreatic mass-forming lesions.

Prediction and stratification of longitudinal risk for chronic obstructive pulmonary disease across smoking behaviors

Smoking is the leading risk factor for chronic obstructive pulmonary disease (COPD) worldwide, yet many people who never smoke develop COPD. We hypothesize that considering other socioeconomic and environmental factors can better predict and stratify the risk of COPD in both non-smokers and smokers. We performed longitudinal analysis of COPD in the UK Biobank to develop the Socioeconomic and Environmental Risk Score (SERS) which captures additive and cumulative environmental, behavioral, and socioeconomic exposure risks beyond tobacco smoking. We tested the ability of SERS to predict and stratify the risk of COPD in current, previous, and never smokers of European and non-European ancestries in comparison to a composite genome-wide polygenic risk score (PGS). We tested associations using Cox regression models and assessed the predictive performance of models using Harrell's C index. SERS (C index = 0.770, 95% CI 0.756 to 0.784) was more predictive of COPD than smoking status (C index = 0.738, 95% CI 0.724 to 0.752), pack-years (C index = 0.742, 95% CI 0.727 to 0.756). Compared to the remaining population, individuals in the highest decile of the SERS had hazard ratios (HR) = 7.24 (95% CI 6.51 to 8.05, P < 0.0001) for incident COPD. Never smokers in the highest decile of exposure risk were more likely to develop COPD than previous and current smokers in the lowest decile with HR=4.95 (95% CI 1.56 to 15.69, P=6.65×10-3) and 2.92 (95%CI 1.51 to 5.61, P=1.38×10-3), respectively. In general, the prediction accuracy of SERS was lower in the non-European populations compared to the European evaluation set. In addition to genetic factors, socioeconomic and environmental factors beyond smoking can predict and stratify COPD risk for both non- and smoking individuals. Smoking status is often considered in screening; other non-smoking environmental and non-genetic variables should be evaluated prospectively for their clinical utility.

Hypercapnic Tissue Gene Expression and Survival in Early-Stage Pancreatic Ductal Adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive and lethal cancer. Hypercapnic tumor microenvironments were previously shown to promote cancer chemoresistance. In this study, we aimed to investigate the impact of tissue hypercapnia on PDAC prognosis.

STUDY DESIGN

PDAC cancer-cell lines were cultured in normocapnic (5% CO 2 ) and hypercapnic conditions (10% CO 2 ). RNA was extracted, and whole-exome transcriptome was sequenced. Differentially expressed genes were identified and used to construct a "hypercapnic gene set." PDAC transcriptomic patient data from the Tumor Cancer Genome Atlas was used to calculate single-sample gene set enrichment scores based on each patient's tissue expression of the hypercapnic gene set. Tissue hypercapnic scores (HSs) in PDAC patients (TMN stages Ia-IIb) were determined and correlated with clinicopathological parameters and overall survival.

RESULTS

A cohort of 135 resected stage I-II PDAC patients were assessed in this study. The average age was 65 ± 11.0 years, and the male:female ratio was 74:61. Median overall survival was 19.5 ± 1.4 months. High HSs were associated with increased tumor stage (p < 0.05) and higher lymph-node ratio (p < 0.05). In active smokers, high HS also correlated with smoking pack-years (p < 0.05). Cox regression analysis revealed high HS to be an independent prognostic factor for overall survival (hazard ratio [HR] 2.66, p = 0.004), along with lymph-node ratio (HR 4.2, p = 0.002) and age at diagnosis (HR 2.63, p = 0.01).

CONCLUSIONS

The pancreatic tumor microenvironment plays an integral role in tumor aggressiveness, and our previous in vitro data suggest that hypercapnia promotes an aggressive, more resistant phenotype. Herein, we show that in early-stage pancreatic cancer, hypercapnic tissue signatures corresponded with a worse overall survival.

A population-based cohort study on the risk of obstructive lung disease after bilateral oophorectomy

There is increasing evidence that sex hormones may impact the development of obstructive lung disease (OLD). Therefore, we studied the effect of bilateral oophorectomy (oophorectomy) on the development of OLD. Women were identified from the Mayo Clinic Cohort Study of Oophorectomy and Aging-2. Data were collected using the Rochester Epidemiology Project records-linkage system. A total of 1653 women who underwent oophorectomy and 1653 referent women of similar age were assessed for OLD using diagnostic codes and medical record abstraction. Women who underwent oophorectomy had an overall higher risk of all OLD, all chronic obstructive pulmonary disease (COPD), emphysema, and chronic bronchitis but not of all asthma, confirmed asthma, or confirmed COPD. The association with all OLD was stronger in women who were age ≤45 years at oophorectomy, never smokers, non-obese, and in women with benign indications; however, the interactions were not statistically significant. There was an increased risk of all asthma in women age ≤45 years at oophorectomy who took estrogen therapy. Never smokers of all ages had a stronger association of oophorectomy with all asthma and all COPD, whereas smokers had a stronger association of oophorectomy with emphysema and chronic bronchitis. Non-obese women of all ages had a stronger association of oophorectomy with all COPD, emphysema, and chronic bronchitis. The results of this study combined with the increased risk of several chronic diseases reported in previous studies suggest that oophorectomy in premenopausal women should be avoided unless there is clear evidence of a high genetic risk of ovarian cancer.

Prevalence and Characteristics of Chronic Obstructive Pulmonary Disease in Dairy Farmers

Objective: To assess the prevalence and characteristics of chronic obstructive pulmonary disease (COPD) in dairy farmers, and evaluate the role of job exposure and smoking as predictors for respiratory health impairment. Methods: A cross-sectional study was performed, including 83 dairy farmers (mean age: 52.6±8.7 years; mean exposure duration: 23.7±7.6 years) and 80 office workers as a control group (mean age: 52.7±8.2 years) matched for age, smoking habits, and socioeconomic status. Methods for evaluation of study participants included a questionnaire on respiratory symptoms in the last 12 months, baseline spirometry and bronchodilator reversibility testing, and diagnostic criteria for COPD. Results: The mean post-bronchodilator values of spirometric parameters are significantly lower in subjects among EG with negative bronchodilator test compared to those in CG, while the mean post-bronchodilator values of spirometric parameters are lower in dairy farmers with negative BD tests exposed more than 20 years compared to those with exposure less than 20 years, being statistically significant for FEV1/FVC%, MEF25, MEF50 and MEF75. The COPD prevalence is non-significantly higher in dairy farmers compared to controls, and is significantly associated with age over 40 years in dairy farmers (P=0.035). The risk for COPD development in dairy farmers is about 36 fold higher in subjects exposed more than 20 years (OR = 36.00 (1.21-37.77) CI 95%) compared to those with exposure duration less than 20 years, and is about 6 fold higher in dairy farmers who are current smokers (OR = 6.12 (0.95-37.77) CI 95%). COPD is significantly associated with smoking duration among smokers in both groups, while combined effect of smoking, smoking duration, and number of cigarettes smoked daily has a significant impact on COPD development in dairy farmers. According to the GOLD classification, depending on the degree of airflow limitation, mild and moderate types of COPD are detected in dairy farmers, and only mild type in controls, showing no significant difference between the two groups. Conclusion: The study findings recognized the role of farming exposure, and smoking as well, as predictors for respiratory health impairment, and furthermore confirmed their potential to be a predictive factor in the COPD development. These facts should be helpful in detection of critical points for action, indicate the need of adverse occupational exposures reduction through adequate preventive measures and regular health examinations, implementation of relevant engineering controls, smoking cessation programs, and complete and efficient respiratory health assessment.

COPD Population in US Primary Care: Data From the Optimum Patient Care DARTNet Research Database and the Advancing the Patient Experience in COPD Registry

PURPOSE

To describe demographic and clinical characteristics of chronic obstructive pulmonary disease patients managed in US primary care.

METHODS

This was an observational registry study using data from the Chronic Obstructive Pulmonary Disease (COPD) Optimum Patient Care DARTNet Research Database from which the Advancing the Patient Experience COPD registry is derived. Registry patients were aged ≥35 years at diagnosis. Electronic health record data were collected from both registries, supplemented with patient-reported information/outcomes from the Advancing the Patient Experience registry from 5 primary care groups in Texas, Ohio, Colorado, New York, and North Carolina (June 2019 through November 2020).

RESULTS

Of 17,192 patients included, 1,354 were also in the Advancing the Patient Experience registry. Patients were predominantly female (56%; 9,689/17,192), White (64%; 9,732/15,225), current/ex-smokers (80%; 13,784/17,192), and overweight/obese (69%; 11,628/16,849). The most commonly prescribed maintenance treatments were inhaled corticosteroid with a long-acting β₂-agonist (30%) and inhaled corticosteroid with a long-acting muscarinic antagonist (27%). Although 3% (565/17,192) of patitents were untreated, 9% (1,587/17,192) were on short-acting bronchodilator monotherapy, and 4% (756/17,192) were on inhaled corticosteroid monotherapy. Despite treatment, 38% (6,579/17,192) of patients experienced 1 or more exacerbations in the last 12 months. These findings were mirrored in the Advancing Patient Experience registry with many patients reporting high or very high impact of disease on their health (43%; 580/1,322), a breathlessness score 2 or more (45%; 588/1,315), and 1 or more exacerbation in the last 12 months (50%; 646/1,294).

CONCLUSIONS

Our findings highlight the high exacerbation, symptom, and treatment burdens experienced by COPD patients managed in US primary care, and the need for more real-life effectiveness trials to support decision making at the primary care level.

Implications of the Immune Landscape in COPD and Lung Cancer: Smoking Versus Other Causes

Cigarette smoking is reported in about one third of adults worldwide. A strong relationship between cigarette smoke exposure and chronic obstructive pulmonary disease (COPD) as well as lung cancer has been proven. However, about 15% of lung cancer cases, and between one fourth and one third of COPD cases, occur in never-smokers. The effects of cigarette smoke on the innate as well as the adaptive immune system have been widely investigated. It is assumed that certain immunologic features contribute to lung cancer and COPD development in the absence of smoking as the major risk factor. In this article, we review different immunological aspects of lung cancer and COPD with a special focus on non-smoking related risk factors.

Prevalence and Population Attributable Risk for Early Chronic Obstructive Pulmonary Disease in U.S. Hispanic/Latino Individuals

Rationale: In predominantly White populations, early chronic obstructive pulmonary disease (COPD) (i.e., COPD in people aged <50 yr) has been linked to higher hospitalization rates and mortality; however, the prevalence, risk factors, and population attributable risk (PAR) of early COPD remain to be determined in non-White populations. Objectives: We aimed to examine the prevalence, risk factors, and PARs of early COPD among Hispanic/Latino individuals, the largest U.S. minority group. Methods: We used baseline data from the Hispanic Community Health Study/Study of Latinos, a population-based probability sample of 16,415 Hispanic/Latino individuals aged 18-74 years. Participants aged <50 years were included (N = 7,323). Early COPD was defined as a forced expiratory volume in 1 second to forced vital capacity ratio less than the lower limit of normal. We used survey logistic regression analysis to identify risk factors and estimate the prevalence of early COPD. PARs of the risk factors identified were estimated. Results: A total of 524 participants met the criteria for early COPD, yielding a sex- and age-adjusted prevalence of 7.6% (95% confidence interval [CI], 6.8-8.6). Asthma (odds ratio [OR], 3.37; 95% CI, 2.57-4.41), smoking status (ever vs. never; OR, 1.65; 95% CI, 1.24-2.20), and chronic sinusitis (OR, 1.71; 95% CI, 1.09-2.66) were associated with increased odds of early COPD. Immigrants versus U.S.-born individuals have lower odds of early COPD (age at immigration <15 yr and living in the United States <10 yr; OR, 0.94; 95% CI, 0.39-2.27; age at immigration <15 yr and living in the United States ⩾10 yr; OR, 0.55; 95% CI, 0.37-0.84; age at immigration ⩾15 yr and living in the United States <10 yr; OR, 0.86; 95% CI, 0.57-1.30; and age at immigration ⩾15 yr and living in the United States ⩾10 yr; OR, 0.63; 95% CI, 0.42-0.95). Among smokers, pack-years was not associated with early COPD (5-9.9 vs. <5 pack-years; OR, 1.04; 95% CI, 0.59-1.82; ⩾10 vs. <5 pack-years; OR, 1.20; 95% CI, 0.74-1.94). The mean PAR for asthma, smoking status, and chronic sinusitis was 26.3% (95% CI, 22.1-30.3), 22.4% (95% CI, 17.4-27.1), and 6.9% (95% CI, 4.3-9.4), respectively. Conclusions: Among U.S. Hispanic/Latino individuals, asthma is one of the most important risk factors for early COPD, followed by smoking and chronic sinusitis. Immigrants appear to have a lower risk of early COPD than U.S.-born Hispanic/Latino individuals.

Association between Dietary Patterns and Chronic Obstructive Pulmonary Disease in Korean Adults: The Korean Genome and Epidemiology Study

In addition to smoking, dietary habits may contribute to the development of chronic obstructive pulmonary disease (COPD). This study aimed to examine the association between dietary patterns and lung function in a Korean community cohort. A total of 5436 participants were included from the Ansan–Ansung cohort study. To identify the dietary patterns, we performed principal component factor analysis using the results of a semi-quantitative food frequency questionnaire. The forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio were measured by spirometry. Multiple logistic regression models were used to evaluate the association between dietary patterns and lung function after adjusting for confounders. We identified four major dietary patterns; ‘prudent’, ‘coffee, fat, and sweet’, ‘westernized’, and ‘white rice’. After adjusting for potential confounders, the ‘coffee, fat, and sweet’ dietary pattern was negatively associated with lung function, particularly the FEV1/FVC ratio. Participants with high scores for the ‘coffee, fat and sweet’ pattern had a higher risk of COPD among men but not women. Therefore, these results indicate that the ‘coffee, fat and sweet’ dietary pattern is inversely related to lung function in Korean adults. Our results indicate that dietary habits may be modifiable risk factors for COPD.

The Impact of Air Pollutants and Meteorological Factors on Chronic Obstructive Pulmonary Disease Exacerbations: A Nationwide Study

RATIONALE Chronic obstructive lung disease (COPD) is a chronic progressive disease. Although smoking is the most important risk factor, 30% of COPD patients are never smokers, and environmental agents are also influential. The effects of air pollutants and meteorological factors on COPD exacerbations have not been studied extensively. OBJECTIVE We aimed to investigate the air pollutants and meteorological factors that impact the incidence of COPD exacerbations. METHODS We obtained clinical data of COPD exacerbation cases from The National Health Insurance Service (NHIS) and merged it with 24-hour average values of air pollutants and meteorological factors from national databases. Patients who reside in eight metropolitan cities, where observatory stations are densely located, were selected for analysis. RESULTS In 1,404,505 COPD patients between 2013 and 2018, 15,282 COPD exacerbations leading to hospitalization or emergency room visits were identified. Among the various air pollutants and meteorological factors, particulate matter (PM)2.5, PM10, NO2, SO2, CO, O3, average temperature and diurnal temperature range (DTR) were associated with COPD exacerbations. GAM model analysis with cubic splines showed an inverted U-shaped relationship with PM2.5, PM10, CO, NO2, SO2, O3, DTR and humidity, while it displayed a U-shaped pattern with the average temperature. Distinct patterns were found from 2015-2016 to 2017-2018. CONCLUSIONS PM2.5, PM10, CO, NO2, O3, SO2, average temperature, humidity, and DTR affected the incidence of COPD exacerbations in various patterns, up to 10 lag days.

Low Vitamin D Status Is Associated with Inflammation in Patients with Chronic Obstructive Pulmonary Disease

Vitamin D deficiency is associated with increased risks of chronic obstructive pulmonary disease (COPD). Nevertheless, the mechanisms remain unknown. This study analyzed the correlations between vitamin D levels and inflammation in COPD patients. One hundred and one patients with COPD and 202 control subjects were enrolled. Serum 25(OH)D level and inflammatory cytokines were detected. Serum 25(OH)D was decreased and inflammatory cytokines were increased in COPD patients. According to forced expiratory volume in 1 s, COPD patients were divided into three grades. Furthermore, serum 25(OH)D was gradually decreased in COPD patients ranging from grade 1-2 to 4. Serum 25(OH)D was inversely associated with inflammatory cytokines in COPD patients. Further analysis found that NF-κB and AP-1 signaling were activated in COPD patients. Besides, inflammatory signaling was gradually increased in parallel with the severity of COPD. By contrast, pulmonary nuclear vitamin D receptor was decreased in COPD patients. In vitro experiments showed that 1,25(OH)₂D₃ inhibited LPS-activated inflammatory signaling in A549 cells (human lung adenocarcinoma cell). Mechanically, 1,25(OH)₂D₃ reinforced physical interactions between vitamin D receptor with NF-κB p65 and c-Jun. Our results indicate that vitamin D is inversely correlated with inflammatory signaling in COPD patients. Inflammation may be a vital mediator of COPD progress in patients with low vitamin D levels.

Pulmonary function is associated with fibrosis severity in patients with biopsy-proven nonalcoholic fatty liver disease

BACKGROUND & AIMS

The association between nonalcoholic fatty liver disease (NAFLD) and pulmonary function remains elusive because of the heterogeneous spectrum and inaccurate diagnostic methods of NAFLD, and insufficient pulmonary function data. We conducted this study to identify the association between histological severity of NAFLD and pulmonary function.

METHODS

This study included patients ≥18 years old with baseline pulmonary function data between August 2014 and July 2019 within a biopsy-evaluated prospective NAFLD cohort. Cross-sectionally, pre-/post-bronchodilator spirometric data with diffusing capacity (DL_CO ) were compared according to histological severity of NAFLD in the various demographic and metabolic subgroups. Multivariable-adjusted analysis revealed specific histological features associated with reduced pulmonary function.

RESULTS

In a total of 420 patients with biopsy-proven NAFLD, pre-/post-bronchodilator forced vital capacities (FVCs; a percentage of the predictive value) were inversely correlated with histological severity of NAFLD. Conversely, pre-bronchodilator forced expiratory volume in 1 second (FEV₁ )/FVC was positively correlated with NAFLD severity. Post-bronchodilator FVC (%) decreased and DL_CO /alveolar volume (V_A ) increased linearly with worsening histological severity of NAFLD in multivariable analysis. In particular, fibrosis stage remained a significant independent predictor of decreased post-bronchodilator FVC (%) (β-coefficient, 4.41; 95% confidence interval [-8.39, -0.43]; P = .031) even after adjusted for clinical variables, exclusively in age <65 years, female, never-smoker and nonchronic obstructive pulmonary disease subgroups.

CONCLUSIONS

Pulmonary function deteriorates with worsening histological severity of NAFLD, especially at the fibrosis stage. The common pathogenesis of reduced pulmonary function and NAFLD fibrosis progression should be further explored.

COPD in Biomass exposed nonsmokers: a different phenotype

INTRODUCTION

Chronic obstructive pulmonary disease, most commonly caused by tobacco smoking, is increasingly reported in nonsmoking patients exposed to domestic combustion of biomass fuels. This is particularly common among rural women in the low- and middle-income countries. It is highly likely that the disease in these patients is a different clinical phenotype.

AREAS COVERED

This manuscript covers epidemiological and clinical aspects of biomass-exposed COPD and also dwells upon its different phenotypic characteristics.

EXPERT OPINION

Chronic obstructive pulmonary disease in biomass-exposed, nonsmoker patients which predominantly presents with features of chronic bronchitis is more likely a distinct phenotype with greater likelihood of small airway involvement.

Effectiveness and Tolerability of LABA/LAMA Fixed-Dose Combinations Aclidinium/Formoterol, Glycopyrronium/Indacaterol and Umeclidinium/Vilanterol in the Treatment of COPD in Daily Practice - Results of the Non-Interventional DETECT Study

Background

LABA (long-acting β2-agonists) and/or LAMA (long-acting muscarinic antagonists) represent the first treatment options for patients with symptomatic COPD. Although both display different mechanisms of activity, in combination they have a stronger broncho-dilating effect than monotherapy; hence, a combination of both LABA and LAMA is particularly recommended for patients whose symptoms cannot be sufficiently improved by a single active ingredient. To date, only few data have been collected regarding the therapeutic outcomes of approved LABA/LAMA fixed-dose combinations (FDCs) under everyday (real-life) conditions in non-clinical trial settings.

Objective and Methods

The main objective of the DETECT study was to investigate the impact of aclidinium/formoterol (AB/FF, b.i.d.), glycopyrronium/indacaterol (GLY/IND, q.d.) and umeclidinium/vilanterol (UME/VL, q.d.) in patients with COPD in daily clinical practice. Therefore, a prospective, non-randomized, 12-month, observational study was implemented to assess the effectiveness of these treatments in patients who had been switched to FDC within the last 3 months or for whom such a changeover was intended. Changes in lung function were analyzed by the forced expiratory volume (FEV1) and forced vital capacity (FVC) measures. Quality of life and well-being were evaluated by the COPD Assessment Test (CAT™). Furthermore, a number of exacerbations and early morning COPD symptoms were documented.

Results

In total, 3653 patients were enrolled. FEV1 and FVC values significantly improved during the study with AB/FF (increase by 0.09 ± 0.40 L and 0.10 ± 0.57 L, respectively; p<0.0001), GLY/IND (0.06±0.38/0.05±0.51 L; p<0.0001 and p=0.0025) and UME/VL (0.12±0.39/0.10±0.52 L; p<0.0001). CAT scores decreased indicating improved COPD (AB/FF, 4.17±8.30; GLY/IND, 3.66±7.88; UME/VL, 4.06±7.96; p<0.0001). Moreover, the number of exacerbations as well as early morning COPD symptoms similarly diminished in all treatment groups. A comparable proportion of patients with adverse drug reactions was recorded: AB/FF, 4.07% of patients; GLY/IND, 3.52%; UME/VL, 3.64%.

Conclusion

In summary, AB/FF, GLY/IND and UME/VL provided clinical benefits in lung function, quality of life and early morning COPD symptoms in a broad cohort of COPD patients under routine medical practice conditions. All three treatments were well tolerated.

Women and COPD: do we need more evidence?

The increasingly female face of chronic obstructive pulmonary disease (COPD) prevalence among women has equalled that of men since 2008, due in part to increased tobacco use among women worldwide and exposure to biomass fuels. This finding is supported by a number of characteristics. There is evidence of susceptibility to smoking and other airborne contaminants, along with epidemiological and phenotypic manifestations. COPD has thus become the leading cause of death in women in the USA. The clinical presentation is characterised by increasingly pronounced dyspnoea with a marked tendency towards anxiety and depression, undernutrition, nonsmall cell lung cancer (especially adenocarcinoma) and osteoporosis. Quality of life is also more significantly impacted. The theories advanced to explain these differences involve the role played by oestrogens, impaired gas exchange in the lungs and smoking habits. While these differences require appropriate therapeutic responses (smoking cessation, pulmonary rehabilitation, long-term oxygen therapy), barriers to the treatment of women with COPD include greater under-diagnosis than in men, fewer spirometry tests and medical consultations. Faced with this serious public health problem, we need to update and adapt our knowledge to the epidemiological changes.

The face of COPD is increasingly female. We need more evidence and a change in how the disease is managed. http://ow.ly/zueL30mWqlS

A Strong Graded Relationship between Level of Obesity and COPD: Findings from a National Population-Based Study of Lifelong Nonsmokers

Factors associated with chronic obstructive pulmonary disease (COPD) among never-smokers have received little research attention. One potential risk factor for COPD is obesity, which is of particular importance in light of the global obesity epidemic. The objective of this study was to investigate the association between COPD and levels of obesity in a nationally representative sample of non-Hispanic white never-smokers. Data were drawn from the 2012 Center for Disease Control's Behavioral Risk Factor Surveillance System (BRFSS). Pearson's chi-square tests and logistic regression analyses were conducted in a large nationally representative sample of non-Hispanic white respondents aged 50 and over (76,004 women; 37,618 men) who reported that they had never smoked. A dose-response relationship was observed for both men and women: the prevalence of COPD increased from 2.5% in men and 3.5% in women who were of a healthy weight (BMI < 25) to 7.6% in men and 13.4% in women who had a BMI of 40 or higher. Even after adjusting for 7 potential confounds (e.g., age, education, and income), the odds of COPD were 3.21 higher for men (95% CI = 2.46, 4.20) and 4.00 higher for women with class III obesity (95% CI = 3.52, 4.55) in comparison with those of healthy weight. Regular screening for COPD is warranted in never-smoking obese patients who are aged 50 and over. Future research is needed to investigate plausible mechanisms for this association, including (1) the role of chronic inflammation associated with obesity and (2) the impact of central obesity on respiratory system mechanics.

[Prevalence and characteristics of chronic obstructive pulmonary disease in non-smokers]

Objetivo

Conocer el perfil y las características de los enfermos diagnosticados de enfermedad pulmonar obstructiva crónica (EPOC) y que nunca han sido fumadores.

Diseño

Estudio descriptivo transversal.

Emplazamiento

Área Básica de Salud del Pla d’Urgell (Atención Primaria de Lleida, España).

Participantes

Se incluyeron los 512 pacientes mayores de 40 años diagnosticados de EPOC del Área Básica de Salud con una espirometría compatible al inicio del estudio [cociente < 0,7 entre el volumen de espiración forzada en el primer segundo (FEV₁) y la capacidad vital forzada (FVC)].

Mediciones principales

La variable dependiente fue la EPOC en no fumadores y las independientes fueron variables recogidas a partir de la información sobre la historia clínica respiratoria, los factores de riesgo del enfermo y sobre calidad vida. Se diseñó un modelo predictor de padecer EPOC en no fumadores en comparación con los fumadores.

Resultados

El 33,2% de los pacientes EPOC nunca habían sido fumadores y de estos, el 59,4% eran mujeres. La media del FEV₁ de los no fumadores fue de 70,5 (DE = 17,1), superior a los 62,6 (DE = 18,5) en los fumadores/exfumadores (p < 0,001). La cobertura de la vacunación antineumocócica 23V era mejor en los no fumadores (75,3%), p < 0,001. Los EPOC en no fumadores (respecto a los fumadores/exfumadores) eran: mayormente mujeres (OR = 16,46), de mayor edad (OR = 1,1), con mejor FEV₁ (OR = 1,1), mejor percepción de calidad de vida, EuroQoL-5D (OR = 0,8), con menor prevalencia de diabetes (OR = 0,5), menor nivel de estudios (OR = 0,2), y con menos hospitalizaciones previas (OR = 0,3).

Conclusiones

El estudio evidencia una alta proporción de no fumadores en enfermos EPOC. Nuestro trabajo objetiva que las mujeres de mayor edad y con menor gravedad se asociarían a un mayor riesgo de EPOC en no fumadores. Parece indicar que la EPOC en no fumadores aparecería en edades más tardías y sería más leve que la EPOC relacionada con el tabaquismo.

The Challenge of Controlling the COPD Epidemic: Unmet Needs

Many unmet needs still remain in the assessment and treatment of patients with chronic obstructive pulmonary disease (COPD), particularly in relation to its under- and misdiagnosis, which lead to under- and mistreatment. This paucity of knowledge about the importance and presence of COPD, as well as its treatment, is seen among patients and carers as well as health care providers. This review considers areas of key educational need, including the clinical characteristics of COPD; factors that contribute to the disease, effective diagnosis, and clinical management of patients; and the implementation of treatment guidelines. As COPD remains the third most frequent cause of death in the world, researchers must continue to expand the scope and reach of their efforts to improve outcomes of this debilitating disease.

The prevalence of chronic airflow obstruction in three cities in the Nordic-Baltic region

BACK GROUND

Chronic airflow obstruction (CAO) is the primary characteristic of Chronic obstructive pulmonary disease (COPD) but is also seen in chronic asthma.

OBJECTIVE

To compare the prevalence of CAO and possible risk factors between Tartu in Estonia, Reykjavik in Iceland and Uppsala in Sweden.

METHODS

All participants underwent spirometry testing of forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) before and after bronchodilation. CAO was defined as post-bronchodilator FEV₁/FVC below lower limit of normal. Information on respiratory diseases and smoking status, was obtained through questionnaires administered by trained interviewers.

RESULTS

1037 men and 956 women participated in the study. The prevalence of CAO was lower in women in Tartu compared to the other centres (4.9% vs. 13.4 and 8.7% in Reykjavik and Uppsala, respectively, p = 0.002) while no difference was found for men. A similar picture was seen for the proportion of participants that had smoked 10 pack years or more which was much lower in Tartu for women than in Reykjavik and Uppsala, respectively (13.2% vs. 33.7 and 29.2%, p < 0.001). (Fig. 1). Of the participants with CAO the majority (57-67%) did not have a previous diagnosis of asthma or COPD.

CONCLUSION

The prevalence of CAO was lower in Estonian women than in women from Iceland and Sweden. The reason for this was probably that the Estonian women had smoked less than the female participants from Iceland and Sweden. The majority of those with CAO do not have a diagnosed lung disease.

The Hypothesis-Driven Physical Examination

The physical examination remains a vital part of the clinical encounter. However, physical examination skills have declined in recent years, in part because of decreased time at the bedside. Many clinicians question the relevance of physical examinations in the age of technology. A hypothesis-driven approach to teaching and practicing the physical examination emphasizes the performance of maneuvers that can alter the likelihood of disease. Likelihood ratios are diagnostic weights that allow clinicians to estimate the post-probability of disease. This hypothesis-driven approach to the physical examination increases its value and efficiency, while preserving its cultural role in the patient-physician relationship.

Epidemiological evidence relating environmental smoke to COPD in lifelong non-smokers: a systematic review

Background: Some evidence suggests environmental tobacco smoke (ETS) might cause chronic obstructive pulmonary disease (COPD). We reviewed available epidemiological data in never smokers. Methods: We identified epidemiological studies providing estimates of relative risk (RR) with 95% confidence interval (CI) for various ETS exposure indices. Confounder-adjusted RRs for COPD were extracted, or derived using standard methods. Meta-analyses were conducted for each exposure index, with tests for heterogeneity and publication bias. For the main index (spouse ever smoked or nearest equivalent), analyses investigated variation in RR by location, publication period, study type, sex, diagnosis, study size, confounder adjustment, never smoker definition, and exposure index definition. Results: Twenty-eight relevant studies were identified; nine European or Middle Eastern, nine Asian, eight American and two from multiple countries. Five were prospective, seven case-control and 16 cross-sectional. The COPD definition involved death or hospitalisation in seven studies, GOLD stage 1+ criteria in twelve, and other definitions in nine. For the main index, random-effects meta-analysis of 33 heterogeneous (p<0.001) estimates gave a RR of 1.20 (95%CI 1.08-1.34). Higher estimates for females (1.59,1.16-2.19, n=11) than males (1.29,0.94-1.76, n=7) or sexes combined (1.10,0.99-1.22, n=15 where sex-specific not available), and lower estimates for studies of 150+ cases (1.08,0.97-1.20, n=13) partly explained the heterogeneity. Estimates were higher for Asian studies (1.34,1.08-1.67, n=10), case-control studies (1.55,1.04-2.32, n=8), and COPD mortality or hospitalisation (1.40,1.12-1.74, n=11). Some increase was seen for severer COPD (1.29,1.10-1.52, n=7). Dose-response evidence was heterogeneous. Evidence for childhood (0.88,0.72-1.07, n=2) and workplace (1.12,0.77-1.64, n=4) exposure was limited, but an increase was seen for overall adulthood exposure (1.20,1.03-1.39, n=17). We discuss study weaknesses that may bias estimation of the association of COPD with ETS. Conclusions: Although the evidence suggests ETS increases COPD, study weaknesses and absence of well-designed large studies precludes reliable inference of causality. More definitive evidence is required.

Incidence and risk of chronic obstructive pulmonary disease in a Korean community-based cohort

Purpose

COPD is a leading cause of morbidity and mortality. However, few studies have used spirometry to investigate its incidence, especially in Asia. In the present study, we analyzed the incidence and risk factors of COPD using a community cohort database in Korea.

Patients and methods

The study included 6,517 subjects aged 40–69 years from the Ansung–Ansan cohort database I–III (2001–2006). We calculated the crude incidence rate and the standardized incidence rate corrected for the Korean general population and the world population with COPD. We also determined the relative risks (RRs) for incident COPD and the attributable risks.

Results

In total, 329 new COPD cases were diagnosed during follow-up. The overall crude incidence rate per 100,000 person-years was 1,447. The standardized incidence rate corrected for the Korean general population was 1,550; this value was higher in men and increased with increasing age. Risk factors for incident COPD were age ≥60 years (adjusted RR [aRR] =2.52 vs age <60 years), male sex (aRR =2.02 vs female), heavy smoking (≥20 pack-years; aRR =2.54 vs never smoker), and lowest income group (first quartile; aRR =2.03 vs fourth quartile). The adjusted attributable risk was highest for education level of high school or lower (44.9%), followed by smoking history (25.8%), income (22.9%), and sex (12.0%).

Conclusion

In Korea, 15.5/1,000 people are diagnosed with COPD annually. The incidence rate increases with increasing age, heavier smoking, and decreasing income, with a higher rate in men than in women.

Epidemiological evidence relating environmental smoke to COPD in lifelong non-smokers: a systematic review

Background: Some evidence suggests environmental tobacco smoke (ETS) might cause chronic obstructive pulmonary disease (COPD). We reviewed available epidemiological data in never smokers. Methods: We identified epidemiological studies providing estimates of relative risk (RR) with 95% confidence interval (CI) for various ETS exposure indices. Confounder-adjusted RRs for COPD were extracted, or derived using standard methods. Meta-analyses were conducted for each exposure index, with tests for heterogeneity and publication bias. For the main index (spouse ever smoked or nearest equivalent), analyses investigated variation in RR by location, publication period, study type, sex, diagnosis, study size, confounder adjustment, never smoker definition, and exposure index definition. Results: Twenty-eight relevant studies were identified; nine European or Middle Eastern, nine Asian, eight American and two from multiple countries. Five were prospective, seven case-control and 16 cross-sectional. The COPD definition involved death or hospitalisation in seven studies, GOLD stage 1+ criteria in twelve, and other definitions in nine. For the main index, random-effects meta-analysis of 33 heterogeneous (p<0.001) estimates gave a RR of 1.20 (95%CI 1.08-1.34). Higher estimates for females (1.59,1.16-2.19, n=11) than males (1.29,0.94-1.76, n=7) or sexes combined (1.10,0.99-1.22, n=15 where sex-specific not available), and lower estimates for studies of 150+ cases (1.08,0.97-1.20, n=13) partly explained the heterogeneity. Estimates were higher for Asian studies (1.34,1.08-1.67, n=10), case-control studies (1.55,1.04-2.32, n=8), and COPD mortality or hospitalisation (1.40,1.12-1.74, n=11). Some increase was seen for severer COPD (1.29,1.10-1.52, n=7). Dose-response evidence was heterogeneous. Evidence for childhood (0.88,0.72-1.07, n=2) and workplace (1.12,0.77-1.64, n=4) exposure was limited, but an increase was seen for overall adulthood exposure (1.20,1.03-1.39, n=17). We discuss study weaknesses that may bias estimation of the association of COPD with ETS. Conclusions: Although the evidence suggests ETS increases COPD, study weaknesses and absence of well-designed large studies precludes reliable inference of causality. More definitive evidence is required.

COPD: time to improve its taxonomy?

Due to well-conducted epidemiological studies and advances in genetics, molecular biology, translational research, the advent of computed tomography of the lungs and bioinformatics, the diagnosis of chronic obstructive pulmonary disease (COPD) as a single entity caused by susceptibility to cigarette smoke is no longer tenable. Furthermore, the once-accepted concept that COPD results from a rapid and progressive loss of lung function over time is not true for a sizeable proportion of adults with the disease. Now we know that some genetic predisposition and/or different environmental interactions (nutritional, infectious, pollution and immunological) may negatively modulate post-natal lung development and lead to poorly reversible airflow limitation later in life, consistent with COPD. We believe it is time to rethink the taxonomy of this disease based on the evidence at hand. To do so, we have followed the principles outlined in the 1980s by J.D. Scadding who proposed that diseases can be defined by four key characteristics: 1) clinical description (syndrome), 2) disorder of structure (morbid anatomy), 3) disorder of function (pathophysiology) and 4) causation (aetiology). Here, we propose a pragmatic approach to the taxonomy of COPD based on different processes that result in a similar syndromic presentation. It can accommodate changes over time, as the pathobiology that may lead to COPD expands. We hope that stakeholders in the field may find it useful to better define the patients now boxed into one single entity, so that specific studies can be designed and conducted for each type of COPDs.

Natural history of COPD: gaps and opportunities

Understanding the natural history of a disease is as important as knowing its cause(s) for effective disease prevention and treatment. Yet, our current understanding of the natural history of chronic obstructive pulmonary disease (COPD) is incomplete and often controversial. This article discusses the current gaps, and hence opportunities for research, in this field. In particular, it discusses the following six specific questions. 1) Is COPD a “single” disease? 2) Is COPD “only” a lung disease? 3) When does COPD begin or what is “early” COPD? 4) How does COPD “progress”? 5) How do we assess disease “severity”? 6) Can COPD be prevented (beyond smoking cessation) or its course be modified once detected?

A new review series starts in ERJ Open Research: “Gaps in our understanding of COPD”http://ow.ly/CFSD30gpXs8

Chronic Obstructive Pulmonary Disease in Elderly Patients

Chronic obstructive pulmonary disease (COPD) is prevalent in the elderly population, with high impact on quality of life, morbidity, and mortality. The diagnosis is usually made based on symptoms and spirometry values that support the presence of airflow obstruction. However, the condition is frequently underdiagnosed. COPD is associated with premature aging and several other medical conditions that can partially explain its underdiagnosis and management. There are several pharmacologic and nonpharmacologic interventions proven to be effective in ameliorating the symptoms of COPD. Appropriate drug delivery and reduction of side effects is also pivotal in the management of patients with COPD.

Chronic Obstructive Pulmonary Disease in Farmers: A Systematic Review

OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is a significant public health problem but it is unclear whether agricultural work causes an increased risk of disease. The aim of this review was to study COPD risk among farmers and analyze occupational exposures in agricultural workplaces.

METHODS

A systematic literature search was conducted to identify epidemiological studies investigating COPD prevalence in farmers.

RESULTS

In the 14 studies reviewed, COPD prevalence ranged from 3% to 68% due to different characteristics of study population, working activities, case definition/diagnosis. Livestock farmers were at higher risk and significant associations were observed for exposure to organic dusts, endotoxins, mites, ammonia, and hydrogen sulfide.

CONCLUSIONS

Farming work was associated with greater risk of developing COPD. However, considering the several variables that may influence the disease prevalence in farmers, we suggest the adoption of a standardized research strategy.

Epidemiology of Lung Disease in Older Persons

Older persons frequently report respiratory risk factors and symptoms and have a high prevalence of symptomatic lung disease, most commonly obstructive airway disease, interstitial lung disease, and lung cancer. Notably, coexisting nonrespiratory risk factors are also prevalent and may misidentify or modify respiratory diagnoses and their clinical course.

Exacerbation of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a disease with high prevalence and substantial associated economical burden. A significant determinant of quality of life, long-term survival, and health care costs is an acute exacerbation of COPD. Acute exacerbations are provoked by respiratory viruses, altered airway microbiome, and environmental factors. The current treatment options are limited. In order to develop specific therapeutic measures, it is important to understand how acute exacerbations evolve. This review focuses on pathophysiology of stable and exacerbated COPD.

Influence of Inhaled Corticosteroids on Bronchial Inflammation and Pulmonary Function in Chronic Obstructive Pulmonary Disease with Moderate Obstruction

Inflammation in the bronchial respiratory tract and lung parenchyma underlies the pathogenesis of chronic obstructive pulmonary disease (COPD). It consists of effector cell infiltration, changes in reticular basement membrane (RBM) thickness, and the content of inflammatory mediators. The aim of this study was to assess the influence of inhaled corticosteroids (ICS) on the number of inflammatory cells and RBM thickness in bronchial biopsies, and pulmonary function in patients with moderate COPD. Twenty four patients with newly diagnosed COPD were included into the study. Pulmonary function tests and fiber optic bronchoscopy with bronchial biopsies were performed before and after 12-month treatment in two groups: ICS- group (LABA plus anticholinergics) and ICS+ group (LABA plus anticholinergics plus ICS). We found that the addition of inhaled corticosteroids to the therapeutic regimen contributed to a reduction of RBM thickness, inflammation, and lung hyperinflation. The intensity of bronchial inflammatory infiltration had little effect on lung function. In conclusion, RBM thickness, an airway wall remodeling element, does not significantly affect the degree of airflow limitation.

The Role of Mitochondria and Oxidative/Antioxidative Imbalance in Pathobiology of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a common preventable and treatable disease, characterized by persistent airflow limitation that is usually progressive and associated with an enhanced chronic inflammatory response in the airways and the lung to noxious particles or gases. The major risk factor of COPD, which has been proven in many studies, is the exposure to cigarette smoke. However, it is 15-20% of all smokers who develop COPD. This is why we should recognize the pathobiology of COPD as involving a complex interaction between several factors, including genetic vulnerability. Oxidant-antioxidant imbalance is recognized as one of the significant factors in COPD pathogenesis. Numerous exogenous and endogenous sources of ROS are present in pathobiology of COPD. One of endogenous sources of ROS is mitochondria. Although leakage of electrons from electron transport chain and forming of ROS are the effect of physiological functioning of mitochondria, there are various intra- and extracellular factors which may increase this amount and significantly contribute to oxidative-antioxidative imbalance. With the coexistence with impaired antioxidant defence, all these issues lead to oxidative and carbonyl stress. Both of these states play a significant role in pathobiology of COPD and may account for development of major comorbidities of this disease.