Passive smoking exposure and risk of COPD among adults in China: the Guangzhou Biobank Cohort Study

Prevalence of Chronic Obstructive Pulmonary Disease and Its Associated Risk Factors in Yunnan Province, China: A Population Based Cross-Sectional Study

Purpose

Chronic obstructive pulmonary disease (COPD) is a significant disease impacting health and quality of life. Yunnan Province, a major tobacco producer, lacks comprehensive COPD studies. The purpose of this study is to describe the epidemic situation of COPD in Yunnan province and explore its influencing factors.

Methods

This study is a cross-sectional research conducted in a representative sample of adults aged 20 and older from 13 prefectures and cities in Yunnan Province, China. COPD was diagnosed using post-bronchodilator pulmonary function tests. Demographics were analyzed with descriptive statistics. The influencing factors of COPD were examined by using the multivariate logistic regression models.

Results

Our study found that high-risk individuals for COPD accounted for 20.30% of the screened population aged 20 and above, with a COPD prevalence of 27.18% among this high-risk group. Male had a higher prevalence (33.01%) than did female (16.35%; p<0.001 for sex difference). Additionally, the proportion of severe and extremely severe COPD cases in Yunnan Province was higher than the national average and other provinces. After considering the potential confounding variables, male (OR=2.291, 95% CI: 1.584-3.313), age (OR=1.501, 95% CI: 1.338-1.685), underweight (OR=1.747, 95% CI: 1.225-2.491), previous smoking (OR=1.712, 95% CI: 1.182-2.478), passive smoking (OR=1.444, 95% CI: 1.159-1.800), and a history of respiratory system diseases in childhood (OR=2.010, 95% CI: 1.346-3.001) were significantly associated with an increased risk of COPD. Conversely, being overweight (OR=0.636, 95% CI: 0.489-0.828), and residing in high-altitude counties (OR=0.445, 95% CI: 0.263-0.754) were negatively correlated with the risk of COPD.

Conclusion

There is significant prevalence of COPD (27.18%) among high-risk population aged 20 and above in Yunnan Province, China. Apart from male, smoking, BMI and other known risk factors for COPD. We found that high-altitude residence had a lower prevalence of COPD. There is no significant difference in COPD prevalence between Han and ethnic minority populations.

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.

Secondhand smoke increases the risk of developing chronic obstructive pulmonary disease

Smoking is the most important risk factor for chronic obstructive pulmonary disease (COPD), however evidence from large-scale studies on whether secondhand smoke (SHS) increases the risk of COPD is still lacking. We conducted this large longitudinal study to investigate the association between SHS and the development of COPD. This is a longitudinal study. Data on 6519 subjects who were never-smokers, had no history of COPD, and had complete lung function records were extracted from the Taiwan Biobank. They were divided into two groups according to SHS exposure: no exposure and exposure groups. Data were collected when participants enrolled in the study and during regular follow-up. Cox proportional hazards regression models were used to estimate the relative risk (RR) and 95% confidence interval (CI) for the association between SHS and the risk of developing COPD. At 48 months of follow-up, 260 (4%) participants in the no exposure group and 34 (7%) participants in the exposure group developed COPD. The RR of incident COPD development was significantly higher in the exposure group than that in the no exposure group after adjusting for confounders (RR = 1.49; 95% CI 1.04 to 2.14; P value = 0.031). There is a dose-response relationship between the duration of exposure to SHS and the risk of incident COPD, which demonstrates that an additional hour of exposure to SHS per week was associated with a 1.03-fold increased likelihood of developing COPD after adjusting for confounders (RR = 1.03; 95% CI 1.00 to 1.05; P value = 0.027). SHS exposure contributes to the development of COPD. This finding can help raise awareness of the harms of SHS and provide a reference for formulating anti-smoking policies.

Prevalence and risk factors for chronic pulmonary aspergillosis in chronic obstructive pulmonary disease patients with acute exacerbations

Chronic obstructive pulmonary disease (COPD) patients often experience acute exacerbations requiring hospitalization. Recently, attention has focused on Aspergillus sensitization in the airways of these COPD patients. This study aimed to assess the prevalence of chronic pulmonary aspergillosis (CPA) in COPD patients with acute exacerbations and identify associated risk factors. A cross-sectional descriptive study was conducted at the Jawaharlal Institute of Postgraduate Medical Education and Research from January 2021 to June 2022. Sixty-one COPD patients presenting with acute exacerbations were included. Demographic details, blood investigations, and sputum examinations were performed for all patients. A high-resolution computed tomography thorax was conducted for eligible patients. The prevalence of CPA among patients with an acute exacerbation of COPD was found to be 9.8%, with chronic cavitary pulmonary aspergillosis being the most common presentation (50%). Among post-tubercular COPD patients, the prevalence of CPA was significantly higher at 22.7%. Hemoptysis (p<0.001) and a previous history of tuberculosis (p=0.008) were associated with Aspergillus sensitization. This study highlights the substantial prevalence of CPA in COPD patients with acute exacerbations, particularly in those with a history of tuberculosis. Early recognition and targeted management of CPA in COPD patients may improve outcomes and reduce hospitalization rates. Further large-scale multi-center studies are needed to validate these findings and comprehensively address the impact of CPA on all COPD patients.

Unusual case of bullous emphysema with superimposed pneumonia

Bullous emphysema is a chronic obstructive pulmonary disease (COPD) that results from chronic inflammation of the lung parenchyma leading to alveolar destruction. Etiology includes tobacco smoking and alpha-1 antitrypsin deficiency. In this article, we present a rare case of bullous emphysema in a nonsmoker with no genetic predisposition or social risk factors presenting with productive cough, fatigue, and shortness of breath. The patient was diagnosed with bullous emphysema with superimposed pneumonia based on clinical and radiological findings. The patients acute complaints were treated successfully with antibiotics, supplemental oxygen, systemic steroids, and, nebulizer treatments. With this case report the authors highlight an unusual presentation of pneumonia in a patient with underlying bullous emphysema. Environmental exposure is often overlooked and the outcomes cannot be turned to favor without a comprehensive approach in patient management from history and physical to deciding the right treatment and follow-up protocols.

The association between blood eosinophils and clinical outcome of acute exacerbations of chronic obstructive pulmonary disease: A systematic review and meta-analysis

OBJECTIVES

Studies have shown an association between eosinophilia and clinical outcomes in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). However, contradictory findings exist. Our study aims to systematically evaluate the association between elevated peripheral blood eosinophils and clinical outcome of patients with AECOPD.

METHODS

An electronic search was conducted for relevant studies published from database inception to February 28, 2023, on PubMed, EMBASE, Cochrane Library, and Web of Science. The analysis covered studies on the correlation between EOS AECOPD and mortality, hospital stay duration, readmission and hospitalization rates, and invasive mechanical ventilation. Where applicable, relative risk (RR) and weighted mean difference (WMD) were extracted, pooled, and assessed using meta-analysis. Sensitivity analysis was performed to explore the source of heterogeneity.

RESULTS

Fifteen high-quality studies including 14 cohort studies and one case-control study were included in the meta-analysis. Compared with non-eosinophilic AECOPD patients, those with eosinophilic AECOPD had a lower risk of mortality (RR = 0.65, 95 % confidence interval [CI] 0.54, 0.77, P < 0.001), shorter length of hospital stay (WMD = -1.56, 95%CI -2.16, -0.96, P < 0.001), and higher readmission rate (RR = 1.07, 95%CI 1.01,1.13, P = 0.029). No difference was found concerning the rate of hospitalization and invasive mechanical ventilation between the two groups.

CONCLUSION

Individuals diagnosed with eosinophilic AECOPD had a reduced mortality rate, a truncated period of hospitalization, and an insubstantial increase in the probability of readmission relative to their non-eosinophilic AECOPD counterparts. The level of eosinophils in blood has been shown to serve as a potential predictive biomarker for AECOPD patients.

Treadmill exercise with nanoselenium supplementation affects the expression of Irisin/FNDC5 and semaphorin 3A in rats exposed to cigarette smoke extract

In the current study, we investigated the impacts of 6 weeks of aerobic interval training (AIT) with selenium nanoparticles (SeNPs) on muscle, serum, and lung irisin (FNDC5) and Sema3A in rats exposed to cigarette smoke extract (CSE). To this end, 49 male Wistar rats (8 weeks old) were divided into seven groups: control, SeNPs (2.5 mg/kg b.w by oral gavage, 3 days/week, 6 weeks), AIT (49 min/day, 5 days/week for 6 weeks, interval), SeNPs + AIT, CSE (150 µL by IP injection, 1 day/week for 6 weeks), CSE + AIT, and CSE + SeNPs + AIT. The CSE group showed a significant reduction in irisin and Sema3A serum levels, as well as a decrease in FNDC5 and Sema3A gene expression in lung tissue (p < 0.05). A combined treatment (AIT with SeNPs) significantly increased the serum level and the expression of muscle and lung irisin (FNDC5) and Sema3A in CSE received groups (p < 0.05). There was a positive and significant correlation between muscle FNDC5 and lung FNDC5 in the CSE + SeNPs + AIT group (r = 0.92, p = 0.025). In addition, there was a positive and significant correlation between serum Sema3A and lung Sema3A of CSE + SeNPs + AIT group (r = 0.97, p = 0.004). Seemingly, performing aerobic exercises with the antioxidant and anti-inflammatory supplement nano-selenium in the model of lung damage (similar to COPD) can boost myokine irisin and Sema3A, especially in serum and lung tissue. These results displayed the paracrine/endocrine regulatory function of these myokines on other tissues. In other words, these interventions emphasized the creation of crosstalk between skeletal muscles and damaged lung, focusing on its recovery; however, further research is needed.

Associations of daytime napping and nighttime sleep quality with depressive symptoms in older Chinese: the Guangzhou biobank cohort study

BACKGROUND

Poor sleep quality has been linked to depression in older adults, but results of the association between daytime napping and depression remains limited and conflicting. Moreover, whether the association of daytime napping with depression varies by nighttime sleep quality is unclear. Hence, we examined the associations of daytime napping and nighttime sleep quality with depressive symptoms in older Chinese.

METHODS

A total of 16,786 participants aged ≥50 from the Guangzhou Biobank Cohort Study second-round examination (2008-2012) were included in this cross-sectional study. Geriatric Depression Scale (GDS-15), Pittsburgh Sleep Quality Index (PSQI), napping and demographic data were collected by face-to-face interview using a computerized questionnaire. Logistic regression was used to calculate odds ratio (OR) of depressive symptoms for napping and sleep quality.

RESULTS

The prevalence of depressive symptoms (GDS score > 5) and poor global sleep quality (PSQI score ≥ 6) was 5.3 and 31.9%, respectively. Compared to non-nappers, nappers showed significantly higher odds of depressive symptoms, with OR (95% confidence interval (CI)) being 1.28 (1.11-1.49). The odds of depressive symptoms for daytime napping varied by nighttime sleep quality (P for interaction = 0.04). In good-quality sleepers, compared to non-nappers, nappers had significantly higher odds of depressive symptoms, with OR (95% CI) being 1.57 (1.23-2.01), whereas no association was found in poor-quality sleepers (OR = 1.13, 0.94-1.36).

CONCLUSION

Napping was associated with higher odds of depressive symptoms in older people, and the association was stronger in good-quality sleepers.

Association between glycated haemoglobin and the risk of chronic obstructive pulmonary disease: A prospective cohort study in UK biobank

AIMS

To investigate the association between glycated haemoglobin (HbA1c) levels and chronic obstructive pulmonary disease (COPD) incidents in the general population, and the association between HbA1c levels and mortality in patients with COPD.

MATERIALS AND METHODS

We investigated the association of HbA1c levels with COPD risk in the general population in the UK Biobank, using data from 420 065 participants. Survival analysis was conducted for 18 854 patients with COPD. We used restricted cubic spline analysis to assess the dose-response relationship between HbA1c levels and COPD risk and survival. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

During a median follow-up of 12.3 years, 11 556 COPD cases were recorded. HbA1c had a non-linear relationship with COPD risk (p for non-linearity < .05). Compared with the quintile 2 (32.2-<34.3 mmol/mol), those with HbA1c levels above 38.7 mmol/mol (quintile 5) had a 22% (HR, 1.22, 95% CI: 1.15-1.30) higher risk of COPD. Compared with the HbA1c decile 2 (30.5-<32.2 mmol/mol), the HRs (95% CI) of COPD risk were 1.16 (1.03-1.30) and 1.36 (1.24-1.50) in the lowest HbA1c decile (<30.5 mmol/mol) and highest decile (≥41.0 mmol/mol), respectively. The increased COPD risk associated with HbA1c was more pronounced in younger, current smokers, passive smokers, and participants with a higher Townsend deprivation index (all p for interaction < .05). Among patients with COPD, 4569 COPD cases died (488 because of COPD) during a median follow-up of 5.4 years. Regarding COPD survival, HbA1c had a non-linear relationship with all-cause death (p for non-linearity < .05). Those with HbA1c quintile 5 (≥38.7 mmol/mol) had a 23% (HR, 1.23, 95% CI: 1.10-1.37) higher risk of all-cause death compared with the quintile 2 (32.2-<34.3 mmol/mol). Compared with the HbA1c decile 4 (33.3-<34.3 mmol/mol), those in the lowest HbA1c decile (<30.5 mmol/mol) and highest HbA1c decile (≥41.0 mmol/mol) had 22% (HR, 1.22; 95% CI: 1.01-1.47) and 28% (HR, 1.28; 95% CI: 1.11-1.48) higher risk for overall death. However, no significant association was observed between HbA1c levels and the risk of COPD-specific death.

CONCLUSIONS

Our findings indicated that lower and higher HbA1c levels were associated with a higher risk of COPD. In COPD cases, lower and higher HbA1c levels were associated with a higher COPD all-cause death risk.

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.

Secondhand Smoke Exposure and the Risk of Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

Background

Many studies have shown that active smoking leads to an increasing incidence of chronic obstructive pulmonary disease (COPD). However, studies interested in the effects of secondhand smoke exposure (SHS exposure) on COPD were less or underappreciated.

Methods

A systematic review and meta-analysis was conducted to investigate the association between SHS exposure and the risk of COPD. Three databases (PubMed, Embase and Web of Science) were searched to obtain data. After assessing the study quality, stratified analyses were performed according to the region, gender, and duration of exposure. Cochran's Q and I² were utilized for heterogeneity assessment. To assess publication bias, we used a funnel plot and Egger's test.

Results

A total of 15 studies (6 cross-sectional studies, 6 case-control studies, and 3 cohort studies) with 25,592 participants were involved in this meta-analysis. This study showed that SHS exposure was associated with an increased risk of COPD (odds ratio (OR): 2.25, 95% CI: 1.40-3.62, I² = 98%, p < 0.01 for heterogeneity based on a random-effects analysis model), especially in those with a longer time exposure of more than 5 years was 4.38 (95% CI: 1.28-15.00, I² = 89%, p < 0.01 for heterogeneity based on a random-effects analysis model). In addition, SHS exposure also increases the risk of COPD in women (odds ratio (OR): 2.02, 95% CI: 1.52-2.67, I² = 0%, p = 0.89 for heterogeneity based on a random-effects analysis model).

Conclusion

The findings suggest that SHS exposure is associated with the risk of COPD, especially for individuals with a long time exposed.

Trial Registry

Prospero CRD42022329421.

HRCT findings in secondhand smokers with respiratory symptoms

PURPOSE

The present study aims to investigate the occurrence and severity of HRCT abnormalities in symptomatic never-smokers, passively exposed to cigarette smoke.

MATERIALS AND METHODS

A total of 135 never-smokers with respiratory symptoms, without underlying lung disease, underwent paired inspiratory-expiratory HRCT and completed the secondhand smoking (SHS) exposure scale questionnaire. Individuals passively exposed to tobacco consisted the secondhand smoking group (SHS group) (n = 68); the remaining 67 controls were never exposed to SHS. Statistical analysis was performed using the Kolmogorov-Smirnov, x² and Pearson Point-Biserial correlation tests. P < 0.05 was statistically significant.

RESULTS

HRCT findings in SHS group included bronchial wall thickening (98.5%), mild cylindrical bronchiectasis (44%), ground-glass opacities (17.6%), and mosaic attenuation pattern (53%). Air trapping occurred in 65% of expiratory scans. Differences in occurrence of findings between SHS group participants and controls were statistically significant (p < 0.0001). There was significant correlation between exposure to tobacco smoke in hours/day and in number of cigarettes/day and the presence of mosaic attenuation pattern, ground-glass opacities, cylindrical bronchiectasis and air trapping, respectively (p < 0.05). Cumulative SHS exposure in years was also strongly correlated with the presence of ground-glass opacities, mosaic attenuation pattern, cylindrical bronchiectasis, and air trapping, as well as with the frequency of respiratory symptoms (p < 0.05).

CONCLUSION

HRCT findings attributed to SHS are mostly related to airway involvement and are correlated with the duration and grade of exposure to environmental tobacco smoke. SHS followed by lifestyle adjustments should be considered in symptomatic non-smokers with such HRCT findings.

Association of sleep duration and napping with stroke mortality in older Chinese: A 14-year prospective cohort study of the Guangzhou Biobank Cohort study

STUDY OBJECTIVE

Evidence regarding the association of short sleep duration and napping with stroke remains limited and controversial. We examined the association of sleep duration and napping with risk of stroke mortality in an older Chinese cohort.

METHODS

Sleep duration and daytime napping were assessed by face-to-face interview during 2003-2008. Information of causes of death until April 30, 2021 was collected via record linkage with the Death Registry. Cox regression was used to calculate the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

Of 27,254 participants aged average 62.0 (standard deviation = 7.1) years, 818 stroke deaths occurred within 388,798 person-years (mean = 14.3 years) of follow-up. A U-shaped relation between sleep duration and risk of stroke mortality was observed. Participants with short (≤5 h/day) or long sleep duration (≥9 h/day) showed higher risks of total stroke mortality, with adjusted HRs (95% CIs) being 1.27 (1.01-1.59) and 1.37 (1.07-1.75), respectively. However, non-significant association of short or long sleep duration with hemorrhagic or ischemic stroke mortality was found. The associations of short and long sleep duration with total stroke mortality were more pronounced in those with hypertension (P for interaction with hypertension = 0.01), with HRs (95% CIs) being 1.37 (1.04-1.82) and 1.77 (1.33-2.36), respectively. No association between napping and risk of stroke mortality was found.

CONCLUSIONS

Both short and long sleep duration, but not daytime napping, were associated with higher risk of stroke mortality. Public health messages to encourage good sleep hygiene may be important, especially for people with hypertension.

Systematic Pharmacology-Based Strategy to Explore the Mechanism of Bufei Huoxue Capsule in the Treatment of Chronic Obstructive Pulmonary Disease

Objective. To explore the effects and mechanisms of Bufei Huoxue Capsule (BHC) on chronic obstructive pulmonary disease (COPD) based on network pharmacology. Methods. The effective components and related targets of BHC were collected by searching TCMSP, HERB, and ETCM databases, after which the related targets of COPD were obtained on GeneCards and OMIM databases. The common targets were imported into the STRING database and Cytoscape database to construct a target interaction network and screen core targets. Next, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed on the Metascape platform. According to the prediction results of network pharmacology, the action mechanism was further examined in an animal model of COPD. The pathological changes of lung tissue were observed by HE staining; goblet cells and mucus secretion in lung tissue were observed by AB-PAS staining, airway collagen deposition was observed by Masson staining, and the expression of NE, TGF-β1, P-EGFR/EGFR, P-ERK1/2/ERK1/2, P-JNK/JNK, and P-P38/P38MAPK protein was detected by Western blot analysis. Results. A total of 379 targets related to BHC and 7391 targets related to COPD were obtained, including 313 potential targets of BHC in treating chronic obstructive pulmonary disease, with JUN, AKT1, TNF, IL6, EGFR, MAPK1, and MAPK14 as the core targets. Through enrichment analysis, BHC may interfere with COPD by regulating the MAPK signal pathway, HIF-1 signal pathway, NF-κB signal pathway, cAMP signal pathway, cGMP-PKG signal pathway, and so on. Animal experiments showed that the BHC could reduce airway inflammatory cell infiltration, inhibit airway epithelial goblet cell proliferation, reduce mucus secretion, and improve small airway collagen fiber deposition in COPD model rats. Besides, BHC could downregulate the protein expression of NE, TGF-β1, P-EGFR, P-ERK1/2, and P-P38MAPK. Conclusion. BHC can reduce airway inflammation, inhibit mucus hypersecretion, and improve airway remodeling by regulating the MAPK signal transduction pathway.

Impact of Airline Secondhand Tobacco Smoke Exposure on Respiratory Health and Lung Function Decades After Exposure Cessation

BACKGROUND

Twenty-five percent to 45% of COPD is caused by exposures other than active smoking. Secondhand tobacco smoke (SHS) has been suggested as an independent cause of COPD, based on its association with increased respiratory symptoms and a small decrease in lung function, but its impact on respiratory health and lung function after exposure cessation has not been explored.

RESEARCH QUESTION

What are the consequences of airline SHS exposure on respiratory health and lung function decades after cessation?

STUDY DESIGN AND METHODS

We performed a cohort study involving flight attendants because of their exposure to SHS that stopped > 20 years ago. We included subjects ≥ 50 years of age with > 1 year vs ≤ 1 year of airline SHS exposure (ie, exposed vs unexposed). Respiratory quality of life, as determined by the St. George's Respiratory Questionnaire (SGRQ), was the primary outcome for respiratory health. Key secondary outcomes included general quality of life (the Rand Corporation modification of the 36-item Short Form Health Survey Questionnaire; RAND-36), respiratory symptoms (COPD Assessment Test; CAT), and spirometry.

RESULTS

The study enrolled 183 SHS-exposed and 59 unexposed subjects. Exposed subjects were 66.7 years of age, and 90.7% were female. They were hired at 23.8 years of age, were exposed to airline SHS for 16.1 years, and stopped exposure 27.5 years before enrollment. Prior SHS exposure was associated with worsened SGRQ (6.7 units; 95% CI, 2.7-10.7; P = .001), RAND-36 physical and social function, and CAT vs unexposed subjects. SHS exposure did not affect prebronchodilator spirometry or obstruction, but was associated with lower postbronchodilator FEV1 and FEV1/FVC, total lung capacity, and diffusing capacity of the lungs for carbon monoxide in a subset of subjects. Former smoking and SHS exposure synergistically worsened SGRQ (β = 8.4; 95% CI, 0.4-16.4; P = .04). SHS exposure in people who never smoked replicated primary results and was associated with worsened SGRQ vs unexposed people (4.7 units; 95% CI, 0.7-7.0; P = .006).

INTERPRETATION

Almost three decades after exposure ended, airline SHS exposure is strongly and dose-dependently associated with worsened respiratory health, but less robustly associated with airflow abnormalities used to diagnose COPD.

Oxidative Stress in Chronic Obstructive Pulmonary Disease

There is a marked increase in oxidative stress in the lungs of patients with COPD, as measured by increased exhaled 8-isoprostane, ethane, and hydrogen peroxide in the breath. The lung may be exposed to exogenous oxidative stress from cigarette smoking and indoor or outdoor air pollution and to endogenous oxidative stress from reactive oxygen species released from activated inflammatory cells, particularly neutrophils and macrophages, in the lungs. Oxidative stress in COPD may be amplified by a reduction in endogenous antioxidants and poor intake of dietary antioxidants. Oxidative stress is a major driving mechanism of COPD through the induction of chronic inflammation, induction of cellular senescence and impaired autophagy, reduced DNA repair, increased autoimmunity, increased mucus secretion, and impaired anti-inflammatory response to corticosteroids. Oxidative stress, therefore, drives the pathology of COPD and may increase disease progression, amplify exacerbations, and increase comorbidities through systemic oxidative stress. This suggests that antioxidants may be effective as disease-modifying treatments. Unfortunately, thiol-based antioxidants, such as N-acetylcysteine, have been poorly effective, as they are inactivated by oxidative stress in the lungs, so there is a search for more effective and safer antioxidants. New antioxidants in development include mitochondria-targeted antioxidants, NOX inhibitors, and activators of the transcription factor Nrf2, which regulates several antioxidant genes.

Risk factors for chronic obstructive pulmonary disease in never‐smokers: A systematic review

Introduction

Relatively little is known about the risk factors for chronic obstructive pulmonary disease (COPD) in never‐smokers, and these factors have not yet been fully characterised. This study therefore sought to analyse COPD risk factors in never‐smokers by conducting a systematic review of the literature on the topic.

Materials and methods

We performed a search in PubMed (Medline) and Embase from 2000 onwards, to locate studies on COPD in never‐smokers. For literature search and evidence synthesis purposes, we used the PRISMA guidelines and drew up a specific quality scale to quantify the evidence of each study included.

Results

The bibliographic search retrieved a total of 557 papers, 20 of which fulfilled the designated inclusion criteria (two case–control studies, four cohort studies and 14 cross‐sectional studies). These studies were undertaken in Europe, the United States, Latin America, Asia and Africa. The risk factors for never‐smokers were varied and ranged from exposure to biomass, occupational exposure and passive smoking to having a history of asthma, tuberculosis or respiratory infections during childhood. The effect of residential radon was unclear. The highest risk was obtained for previous respiratory diseases of any type, with a magnitude much higher than that observed for other risk factors.

Conclusions

There are few studies on COPD risk factors in never‐smokers. More purpose‐designed studies in this subpopulation are thus called for, including well‐designed studies to specifically assess if indoor radon has any role on COPD onset.

Do deaths from competing risks influence COPD patterns in China and high socio-demographic index countries?: a cross-sectional analysis of summary statistics from the Global Burden of Disease Study 2017

OBJECTIVE

To explore possible reasons for the difference in chronic obstructive pulmonary disease (COPD) incidence/mortality rates between China and high socio-demographic index (SDI) countries.

DESIGN

A cross-sectional analysis of summary statistics from the Global Burden of Disease Study 2017.

PARTICIPANTS

Data were publicly available and de-identified, and individuals were not involved.

MEASUREMENT AND METHODS

We extracted the age-standardised and age-specific incidence/mortality rates, and risk factors attributed to COPD in China and high SDI countries from the Global Burden of Disease Study 2017. We first described differences in COPD patterns (ie, incidence and mortality rates) in China and high SDI countries briefly, and then explored possible reasons for driving such differences by comparing rankings for six well-established COPD risk factors and estimating change points in age-specific incidence and mortality rates for COPD and several commonly encountered competing risks using segmented regression models.

RESULTS

Differences in age-standardised incidence and mortality rates for COPD between China and high SDI countries converged during 1990-2017 but still differed, particularly for mortality rates. Smoking was the leading attributable risk factor followed by ambient air pollution, with higher rankings for occupational risks in China than in high SDI countries. The change point was ~80 years for age-specific COPD mortality rate in both China and high SDI countries. However, the change point for COPD incidence was 5-year later in China (~65 years) than in high SDI countries (~60 years). The change points for mortality rates due to competing risks (eg, ischaemic heart disease) also varied between settings.

CONCLUSION

Differences in risk factors largely shaped the differences in COPD patterns between China and high SDI countries. Varying patterns of mortality due to competing risks might also contribute to the discrepancy in COPD mortality rates, by affecting the survival of the underlying population.

Epidemiological evidence relating risk factors to chronic obstructive pulmonary disease in China: A systematic review and meta-analysis

BACKGROUND

Chronic obstructive pulmonary disease (COPD), the most common chronic respiratory disease worldwide, not only leads to the decline of pulmonary function and quality of life consecutively, but also has become a major economic burden on individuals, families, and society in China. The purpose of this meta-analysis was to explore the risk factors for developing COPD in the Chinese population that resides in China and to provide a theoretical basis for the early prevention of COPD.

METHODS

A total of 2457 cross-sectional, case-control, and cohort studies published related to risk factors for COPD in China were searched. Based on the inclusion and exclusion criteria, 20 articles were selected. Stata 11.0 was used for meta-analysis. After merging the data, the pooled effect and 95% confidence intervals (CIs) were calculated to assess the association between risk factors and COPD. Heterogeneity between studies was assessed using I2 and Cochran's Q tests. Begg's test was used to assess publication bias.

RESULTS

Exposure to particulate matter less than 2.5 μm in diameter (PM2.5) (pooled effect = 1.73; 95%CI: 1.16~2.58; P <0.01), smoking history (pooled effect = 2.58; 95%CI: 2.00~3.32; P <0.01), passive smoking history (pooled effect = 1.39; 95%CI: 1.03~1.87; P = 0.03), male sex(pooled effect = 1.70; 95%CI: 1.31~2.22; P <0.01), body mass index (BMI) <18.5 kg/m2 (pooled effect = 1.73; 95%CI: 1.32~2.25; P <0.01), exposure to biomass burning emissions (pooled effect = 1.65; 95%CI: 1.32~2.06; P <0.01), childhood respiratory infections (pooled effect = 3.44; 95%CI: 1.33~8.90; P = 0.01), residence (pooled effect = 1.24; 95%CI: 1.09~1.42; P <0.01), and a family history of respiratory diseases (pooled effect = 2.04; 95%CI: 1.53~2.71; P <0.01) were risk factors for COPD in the Chinese population.

CONCLUSION

Early prevention of COPD could be accomplished by quitting smoking, reducing exposure to air pollutants and biomass burning emissions, maintaining body mass index between 18.5 kg/m2 and 28 kg/m2, protecting children from respiratory infections, adopting active treatments to children with respiratory diseases, and conducting regular screening for those with family history of respiratory diseases.

Comparative Effectiveness and Safety of Seven Qi-Tonifying Chinese Medicine Injections for AECOPD Patients: A Systematic Review and Network Meta-Analysis

Introduction

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) imposes a large burden on economy and society worldwide. In addition to western medicine, multiple kinds of qi-tonifying Chinese medicine injections have been widely used in China as adjunctive treatments. Previous small-sample clinical trials have proven their efficacy in the treatment of AECOPD. However, data on comparative effectiveness and safety of qi-tonifying injections are limited. We conducted this network meta-analysis to compare the efficacy and safety of 7 commonly used qi-tonifying injections in patients with AECOPD.

Methods

Literature search was conducted through electronic databases, including PubMed, the Cochrane Library, EMBASE, CINAHL, AMED, CBM, CNKI, Wanfang database, and VIP database. Randomized clinical trials (RCTs) exploring the efficacy of any of these 7 qi-tonifying injections were included. The primary outcome was lung function (FEV1 and FVC). R 4.0.0 and STATA 12.0 were adopted to perform the network meta-analysis using Bayesian statistics.

Results

A total of 36 RCTs involving 2657 participants were included. The results of network meta-analyses indicated that Chuankezhi injection (CKZ) combined with routine treatment (RT) was superior to other qi-tonifying injections combined with RT in terms of FEV1 improvement (MD = 0.63, 95% CI: 0.22, 1.04). For improving FVC, Shengmai injection (SGM) combined with RT showed the greatest therapeutic effect (MD = 0.38, 95% CI: 0.13, 0.61). Moreover, SGM combined with RT revealed the best estimates for response rate (MD = 4.00, 95% CI: 1.34, 13.63). The main adverse events in this study were gastrointestinal reactions and injection site reactions. No serious adverse events were reported.

Conclusion

In this network meta-analysis, SGM and CKZ were potential best adjunctive therapies in the treatment of AECOPD.

Second-Hand Smoke Exposure Associated with Risk of Respiratory Symptoms, Asthma, and COPD in 20,421 Adults from the General Population

Rationale

Individuals exposed to second-hand smoking may be more susceptible to asthma and chronic obstructive pulmonary disease (COPD). We investigated the risk of respiratory symptoms, asthma, and COPD in adults exposed to second-hand smoking at different stages of life in the general population.

Methods

We identified individuals who had been exposed to second-hand smoking in childhood only, adulthood only, or lifelong in a cohort of 20,421 adults from the Danish General Suburban Population Study and recorded respiratory symptoms, lung function, asthma, and COPD as outcomes.

Results

Among 20,421 adults from the general population, 2,551 (12%) had been lifelong exposed to second-hand smoking, 459 (2%) had been exposed in adulthood only, and 13,998 (69%) had been exposed in childhood only; the mean ages of the three groups were 54 years, 55 years, and 57 years, respectably, compared with 56 years in non-exposed individuals (P<0.001). Equivalent values for the prevalence of current smoking were 25%, 20%, and 18% versus 12% (P<0.001). After adjustment for age, smoking, and sex, the odds ratios for wheezing, severe dyspnoea, cough on exertion, and asthma increased as a function of second-hand smoke exposure (Ps≤0.004); individuals who had been exposed to second-hand smoking lifelong, in adulthood only, or in childhood only versus non-exposed had increased odds ratios for wheezing of 1.62 (95% CI=1.41–1.87), 1.50 (1.15–1.94), and 1.16 (1.04–1.30). Corresponding values were 2.08 (1.52–2.85), 2.05 (1.22-3-44), and 1.23 (0.95–1.59) for severe dyspnoea, 1.56 (1.33–1.83), 1.53 (1.15–2.02), and 1.19 (1.05–1.35) for cough on exertion, 1.36 (1.14–1.63), 1.49 (1.09–2.05), and 1.13 (0.99–1.30) for asthma, and 1.24 (1.03–1.48), 1.25 (0.90–1.74), and 1.09 (0.96–1.24) for COPD. The population attributable fractions of asthma and COPD due to lifelong second-hand smoke exposure were 4.3% and 2.9%.

Conclusion

Individuals exposed to lifelong second-hand smoking have increased risks of respiratory symptoms, asthma, and COPD, and may account for 4.3% and 2.9% of people with asthma and COPD in the general population.

Case-finding and improving patient outcomes for chronic obstructive pulmonary disease in primary care: the BLISS research programme including cluster RCT

Background

Chronic obstructive pulmonary disease is a major contributor to morbidity, mortality and health service costs but is vastly underdiagnosed. Evidence on screening and how best to approach this is not clear. There are also uncertainties around the natural history (prognosis) of chronic obstructive pulmonary disease and how it impacts on work performance.

Objectives

Work package 1: to evaluate alternative methods of screening for undiagnosed chronic obstructive pulmonary disease in primary care, with clinical effectiveness and cost-effectiveness analyses and an economic model of a routine screening programme. Work package 2: to recruit a primary care chronic obstructive pulmonary disease cohort, develop a prognostic model [Birmingham Lung Improvement StudieS (BLISS)] to predict risk of respiratory hospital admissions, validate an existing model to predict mortality risk, address some uncertainties about natural history and explore the potential for a home exercise intervention. Work package 3: to identify which factors are associated with employment, absenteeism, presenteeism (working while unwell) and evaluate the feasibility of offering formal occupational health assessment to improve work performance.

Design

Work package 1: a cluster randomised controlled trial with household-level randomised comparison of two alternative case-finding approaches in the intervention arm. Work package 2: cohort study – focus groups. Work package 3: subcohort – feasibility study.

Setting

Primary care settings in West Midlands, UK.

Participants

Work package 1: 74,818 people who have smoked aged 40–79 years without a previous chronic obstructive pulmonary disease diagnosis from 54 general practices. Work package 2: 741 patients with previously diagnosed chronic obstructive pulmonary disease from 71 practices and participants from the work package 1 randomised controlled trial. Twenty-six patients took part in focus groups. Work package 3: occupational subcohort with 248 patients in paid employment at baseline. Thirty-five patients took part in an occupational health intervention feasibility study.

Interventions

Work package 1: targeted case-finding – symptom screening questionnaire, administered opportunistically or additionally by post, followed by diagnostic post-bronchodilator spirometry. The comparator was routine care. Work package 2: twenty-three candidate variables selected from literature and expert reviews. Work package 3: sociodemographic, clinical and occupational characteristics; occupational health assessment and recommendations.

Main outcome measures

Work package 1: yield (screen-detected chronic obstructive pulmonary disease) and cost-effectiveness of case-finding; effectiveness of screening on respiratory hospitalisation and mortality after approximately 4 years. Work package 2: respiratory hospitalisation within 2 years, and barriers to and facilitators of physical activity. Work package 3: work performance – feasibility and acceptability of the occupational health intervention and study processes.

Results

Work package 1: targeted case-finding resulted in greater yield of previously undiagnosed chronic obstructive pulmonary disease than routine care at 1 year [n = 1278 (4%) vs. n = 337 (1%), respectively; adjusted odds ratio 7.45, 95% confidence interval 4.80 to 11.55], and a model-based estimate of a regular screening programme suggested an incremental cost-effectiveness ratio of £16,596 per additional quality-adjusted life-year gained. However, long-term follow-up of the trial showed that at ≈4 years there was no clear evidence that case-finding, compared with routine practice, was effective in reducing respiratory admissions (adjusted hazard ratio 1.04, 95% confidence interval 0.73 to1.47) or mortality (hazard ratio 1.15, 95% confidence interval 0.82 to 1.61). Work package 2: 2305 patients, comprising 1564 with previously diagnosed chronic obstructive pulmonary disease and 741 work package 1 participants (330 with and 411 without obstruction), were recruited. The BLISS prognostic model among cohort participants with confirmed airflow obstruction (n = 1894) included 6 of 23 candidate variables (i.e. age, Chronic Obstructive Pulmonary Disease Assessment Test score, 12-month respiratory admissions, body mass index, diabetes and forced expiratory volume in 1 second percentage predicted). After internal validation and adjustment (uniform shrinkage factor 0.87, 95% confidence interval 0.72 to 1.02), the model discriminated well in predicting 2-year respiratory hospital admissions (c-statistic 0.75, 95% confidence interval 0.72 to 0.79). In focus groups, physical activity engagement was related to self-efficacy and symptom severity. Work package 3: in the occupational subcohort, increasing dyspnoea and exposure to inhaled irritants were associated with lower work productivity at baseline. Longitudinally, increasing exacerbations and worsening symptoms, but not a decline in airflow obstruction, were associated with absenteeism and presenteeism. The acceptability of the occupational health intervention was low, leading to low uptake and low implementation of recommendations and making a full trial unfeasible.

Limitations

Work package 1: even with the most intensive approach, only 38% of patients responded to the case-finding invitation. Management of case-found patients with chronic obstructive pulmonary disease in primary care was generally poor, limiting interpretation of the long-term effectiveness of case-finding on clinical outcomes. Work package 2: the components of the BLISS model may not always be routinely available and calculation of the score requires a computerised system. Work package 3: relatively few cohort participants were in paid employment at baseline, limiting the interpretation of predictors of lower work productivity.

Conclusions

This programme has addressed some of the major uncertainties around screening for undiagnosed chronic obstructive pulmonary disease and has resulted in the development of a novel, accurate model for predicting respiratory hospitalisation in people with chronic obstructive pulmonary disease and the inception of a primary care chronic obstructive pulmonary disease cohort for longer-term follow-up. We have also identified factors that may affect work productivity in people with chronic obstructive pulmonary disease as potential targets for future intervention.

Future work

We plan to obtain data for longer-term follow-up of trial participants at 10 years. The BLISS model needs to be externally validated. Our primary care chronic obstructive pulmonary disease cohort is a unique resource for addressing further questions to better understand the prognosis of chronic obstructive pulmonary disease.

Trial registration

Current Controlled Trials ISRCTN14930255.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 9, No. 13. See the NIHR Journals Library website for further project information.

A population-based survey of the prevalence and risk factors of chronic obstructive pulmonary disease in Shanxi Province, China

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory disease which can cause organ damage and even death. For the first time, the prevalence and risk factors of COPD in Shanxi Province (China) were evaluated in this study.

METHODS

A population-based survey was conducted in 2015 based on the Shanxi Province population (age ≥ 20). COPD was diagnosed according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) standard (2017).

RESULTS

A total of 5636 participants with reliable post-bronchodilator results were selected. The prevalence of spirometry-defined COPD among the population (age ≥ 20) was 6.4% (95% CI 5.8-7.1) and was more prevalent in men (9.7%, 95% CI 8.6-10.9) than women (3.9%, 95% CI 3.2-4.6). The multivariate-adjusted analysis demonstrated that sex, age, education, smoking, chronic cough during childhood (age ≤ 14), and a family history of parents with respiratory diseases were related to the prevalence of COPD risk. On the contrary, among rural residents living with smokers, a history of pneumonia or bronchitis during childhood, BMI, use of biomass energy, prolonged exposure to particulate matter 2.5, and a family history of parents with respiratory diseases did not show a significant correlation to COPD.

CONCLUSIONS

We have identified a high prevalence of COPD and its determinants in Shanxi province. The prevention of COPD and its early detection is a health priority in this province.

Brain-derived neurotrophic factor gene variants and obesity in former smokers

OBJECTIVE

From genome-wide association studies, brain-derived neurotrophic factor (BDNF) locus on chromosome 11 was the only SNP associated with both smoking and body mass index (BMI) in European, African and Asian population. This study aims to explore the unique genetic predisposition to obesity in former smokers by examining the effects of BDNF on BMI and waist circumference (WC).

METHODS

The study design is case-control study with a cohort validation in supplementary. We included 15,072 ethnic Chinese participants in the Guangzhou Biobank Cohort Study (GBCS) with data of four BDNF SNPs related to both BMI and smoking behavior. We used baseline smoke exposure data in 2003-2007 and follow-up outcomes of general obesity (by BMI) and central obesity (WC) in 2008-2012. Odds ratios (ORs) and 95% confidence intervals (CIs) for general obesity and central obesity associated with these SNPs were derived from logistic regression.

RESULTS

Of 15,072 participants (3169 men and 11,903 women), 1664 (11.0%) had general and 7868 (52.2%) had central obesity. In 1233 former smokers, the rs6265 GG, versus AA, genotype was associated with higher risks of general obesity (OR = 1.79, 95% CI = 1.06-3.01) and central obesity (OR = 2.08, 95% CI = 1.47-2.92) after adjustment. These associations were not significant in never or current smokers. In former heavy (≥20 cigarettes/day) smokers, the rs6265 GG genotype showed a higher odds for general obesity (OR = 2.15, 95% CI = 1.05-4.40), while no association was found in former light (1-9 cigarettes/day) smokers. Similar results were found for the association of rs6265 with central obesity and for the associations of other two BDNF SNPs (rs4923457 and rs11030104) with both general and central obesity.

CONCLUSIONS

We firstly identified the genetic predisposition (BDNF SNPs) to general and central obesity in former smokers, particularly in former heavy smokers. The different associations of the SNPs for general/central obesity in different smoke exposure groups may be related to the competitive performance of the sites and epigenetic modification, which needs further study.

Asthma Patients Benefit More Than Chronic Obstructive Pulmonary Disease Patients in the Coronavirus Disease 2019 Pandemic

Background: Coronavirus disease 2019 (COVID-19) has raised many questions about the role of underlying chronic diseases on disease outcomes. However, there is limited information about the effects of COVID-19 on chronic airway diseases. Therefore, we conducted the present study to investigate the impact of COVID-19 on patients with asthma or chronic obstructive pulmonary disease (COPD) and ascertain risk factors for acute exacerbations (AEs). Methods: This single-center observational study was conducted at the Second Xiangya Hospital of Central South University, involving asthma or COPD patients who had been treated with inhaled combination corticosteroids (ICSs), such as budesonide, and one long-acting beta-2-agonist (LABA), such as formoterol, for at least a year before the COVID-19 pandemic. We conducted telephone interviews to collect demographic information and clinical data between January 1, 2019, and December 31, 2020, focusing on respiratory and systemic symptoms, as well as times of exacerbations. Data for asthma and COPD were then compared, and the risk factors for AEs were identified using logistic regression analysis. Results: A total of 251 patients were enrolled, comprising 162 (64.5%) who had asthma and 89 who had COPD, with none having COPD/asthma overlap. Frequency of AEs among asthma patients was significantly lower in 2020 than in 2019 (0.82 ± 3.33 vs. 1.00 ± 3.16; P < 0.05). Moreover, these patients visited the clinic less (0.37 ± 0.93 vs. 0.49 ± 0.94; P < 0.05) and used emergency drugs less (0.01 ± 0.11 vs. 007 ± 0.38; P < 0.05) during the COVID-19 pandemic. In contrast, among COPD patients, there were no significant differences in AE frequency, clinic visits, or emergency drug use. Furthermore, asthma patients visited clinics less frequently during the pandemic than those with COPD. Logistic regression analysis also showed that a history of at least one AE within the last 12 months was associated with increased AE odds for both asthma and COPD during the COVID-19 pandemic (odds ratio: 13.73, 95% CI: 7.04-26.77; P < 0.01). Conclusion: During the COVID-19 pandemic, patients with asthma showed better disease control than before, whereas patients with COPD may not have benefited from the pandemic. For both diseases, at least one AE within the previous 12 months was a risk factor for AEs during the pandemic. Particularly, among asthma patients, the risk factors for AE during the COVID-19 pandemic were urban environment, smoking, and lower asthma control test scores.

Occupational exposure to particles and increased risk of developing chronic obstructive pulmonary disease (COPD): A population-based cohort study in Stockholm, Sweden

OBJECTIVES

Chronic Obstructive Pulmonary Disease (COPD) is a common respiratory disorder. Next to tobacco smoking, occupational exposure is the most important risk factor for COPD in high-income countries. To enable preventative measures, more knowledge is needed on which specific occupational exposures that are related to risk of developing COPD in men and women.

METHODS

A population-based cohort was formed from subjects responding to the Stockholm Public Health Surveys in 2002, 2006, and 2010, followed up until 2014. The dataset was linked to a quantitative job exposure matrix via occupational titles from the 1990 nation-wide Population and housing census. We identified COPD among subjects having medication for COPD and/or reporting a physician's diagnosis of COPD. The gender-specific risks to develop COPD from occupational particle-exposure were estimated by proportional hazards regression model, adjusted for age and individual data on tobacco-smoking.

RESULTS

Men exposed to respirable crystalline silica (RCS) (HR 1.46, CI 1.13-1.90), gypsum and insulation material (HR 1.56, CI 1.18-2.05), diesel exhaust (HR 1.18, CI 0.99-1.41) and high levels of particles from asphalt/bitumen (HR 1.71, CI 1.06-2.76) as well as welding fumes (HR 1.57, CI 1.12-2.21) had an increased smoking-adjusted risk for developing COPD. An increased risk was also observed among women highly exposed to various organic particles from soil, leather, plastic, soot, animal, textile, flour (HR 1.53, CI 1.15-2.04). Furthermore, a significant positive exposure-response trend was found among men exposed to RCS, iron dust, gypsum and insulation material, and diesel exhaust. A tendency towards an exposure-response relationship was also seen among both men and women exposed to welding fumes and various organic particles, and among men exposed to particles from asphalt/bitumen. The population attributable fraction for COPD from occupational exposure to particles was 10.6% among men and 6.1% among women.

CONCLUSIONS

This study indicates an increased smoking-adjusted risk of developing of COPD due to occupational exposure to particles. A positive exposure-response relationship was found for RCS, gypsum and insulation, diesel exhaust, and welding fumes. Also, exposure to high levels of asphalt/bitumen and various organic particles was associated with a higher risk for COPD. Reduction of these exposures in the work environment are important to prevent future cases of COPD. More studies are needed to investigate exposure-response relationships further, but this study indicates that the European occupational exposure limit (OEL) for RCS needs to be re-evaluated.

Smoking status affects clinical characteristics and disease course of acute exacerbation of chronic obstructive pulmonary disease: A prospectively observational study

Existing studies primarily explored chronic obstructive pulmonary disease (COPD) in smokers, whereas the clinical characteristics and the disease course of passive or nonsmokers have been rarely described. In the present study, patients hospitalized and diagnosed as acute exacerbation of COPD (AECOPD) were recruited and followed up until being discharged. Clinical and laboratory indicators were ascertained and delved into. A total of 100 patients were covered, namely, 52 active smokers, 34 passive smokers, and 14 nonsmokers. As revealed from the results here, passive or nonsmokers developed less severe dyspnea (patients with modified Medical Research Council scale (mMRC) <2, 0.0% vs. 8.8% vs. 14.3%, p < 0.05, active, passive, and nonsmokers, respectively), higher oxygenation index (206.4 ± 45.5 vs. 241.2 ± 51.1 vs. 242.4 ± 41.8 mmHg, p < 0.01), as well as lower arterial partial pressure of carbon dioxide (70.8 ± 12.7 vs. 58.85 ± 9.9 vs. 56.6 ± 6.5 mmHg, p < 0.001). Despite lower treatment intensity over these patients, amelioration of dyspnea, mitigation of cough, and elevation of oxygenation index were comparable to those of active smokers. However, in terms of patients exhibiting mMRC ≥2 and type 2 respiratory failure, amelioration of dyspnea was more common in nonsmokers as compared with passive smokers (46.4% vs. 83.3%, p < 0.05, passive and nonsmokers, respectively). In terms of patients exhibiting Global Initiative for COPD severity <3, mMRC ≥2, and type 2 respiratory failure, active smokers achieved the least mitigation of cough symptom (8.7% vs. 35.0% vs. 44.4%, p < 0.05). Similar results could be achieved after the effects of confounders were excluded, with the most prominent amelioration of dyspnea (odds ratio (OR) 3.8, 95% confidence interval (CI) 1.1-13.6, p < 0.05, as compared with active smokers) and cough (OR 3.3, 95% CI 1.0-10.7, p < 0.05) in nonsmokers, and relatively better amelioration of hypoxemia in passive smokers (oxygenation index change, 39.0 ± 34.6 vs. 51.5 ± 32.4 vs. 45.3 ± 25.4 mmHg, p < 0.05). In brief, passive or nonsmokers with AECOPD were subjected to less severe disease, and nonsmokers, especially patients with more severe disease, might achieve the optimal enhancement of clinical presentation after treatment.

Current status and preventive strategies of chronic obstructive pulmonary disease in China: a literature review

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease that seriously threatens human health and wellbeing, thereby representing an important public health problem. At present, it is the fourth leading cause of death worldwide, and is estimated to become the third greatest cause of death by 2030. In China, the prevalence of COPD is increasing, secondary to an increase in smoking, air pollution and an aging population, resulting in a current the mortality of COPD in China which is higher than the global average. Moreover, the disability-adjusted life year (DALY) rate of COPD in China is still relatively high, with an associated heavy economic burden to patients, their families and society. Unfortunately, current measures for treatment and prevention of COPD in China are not optimal. This primarily results from limited public awareness of COPD and pulmonary function tests amongst residents of China, and the generally poor disease-specific knowledge of primary care doctors. In recent years, a series of preventative strategies have been introduced in China across at the level of national policy, societies and associations, and scientific research. This review focuses upon both the epidemiology of COPD and the current status of preventative and treatment strategies in China.

The Impact of Depression and Anxiety on Chronic Obstructive Pulmonary Disease Acute Exacerbations: A prospective cohort study

BACKGROUND

To explore the impact of anxiety and depression in chronic obstructive pulmonary disease(COPD) patients on the risk of acute exacerbation.

METHODS

600 COPD patients were recruited and followed in Beijing, China. The demographic data, medical history, smoking history, therapy, assessments for anxiety and depression were completed by our physicians by face-to-face interview. Then the acute exacerbation events during the past one year was derived from their case record.

RESULTS

504 people (295 men and 209 women) were thus included in the final analyses.The patients with anxiety scored more than 50 showed higher risk of acute exacerbation(54.1%) than those who scoring less than 50(39.8%). Similarly, the patients with depression scored more than 53 showed higher risk of acute exacerbation(52.1%) than those who scoring less than 53(40.4%). Eventually, Anxiety and/or depression will increase the risk of acute exacerbation in chronic obstructive pulmonary disease patients(AECOPD) (adjusted OR = 1.60, 95%CI: 1.10-2.31), after adjusting the influence of family history, duration of disease, BMI index and other factors. Besides, the prevalence of acute exacerbation in patients with anxiety and/or depression was higher than those without acute exacerbation (P<0.05).

LIMITATIONS

The frequency of AECOPD was limited to self-reported data, recall bias should be reconsidered, and it also may underestimate the association between anxiety and/or depression and AECOPD. Anxiety and depression were assessed by questionnaires rather than by a clinical diagnosis.

CONCLUSION

Anxiety and/or depression in stable COPD patients were significantly associated with a higher risk of acute exacerbation. Mental health care should be paid more attention, to decrease the risk of acute exacerbation in COPD patients.

The role of cigarette smoke-induced pulmonary vascular endothelial cell apoptosis in COPD

Chronic obstructive pulmonary disease (COPD) is one of the most common chronic respiratory diseases with high morbidity and mortality. It has become the fifth most burdened and the third most deadly disease in the global economy and increases year by year. The prevention and treatment of COPD are urgent. Smoking is the main and most common risk factor for COPD. Cigarette smoke (CS) contains a large number of toxic substances, can cause a series of changes in the trachea, lung tissue, pulmonary blood vessels, and promotes the occurrence and development of COPD. In recent years, the development of epigenetics and molecular biology have provided new guidance for revealing the pathogenesis, diagnosis, and treatment of diseases. The latest research indicates that pulmonary vascular endothelial cell apoptosis initiates and participates in the pathogenesis of COPD. In this review, we summarize the current research on the epigenetic mechanisms and molecular biology of CS-induced pulmonary vascular endothelial cell apoptosis in COPD, providing a new research direction for pathogenesis of COPD and a new target for the diagnosis, treatment, and prevention of COPD.

COPD in the major nonsmoking adult: A systematic review and meta-analysis

Chronic Obstructive Pulmonary Disease (COPD) main cause is attributed to active smokers, but there's a small percentage that comes from risk factors that have been less considered. The aim of this research was to identify the risk factors and the clinical presentation of the population over 64 years of age that lead to the development of COPD. A systematic review and a meta-analysis was performed. From the 92 studies interpreted, we identified seven studies on the presence of COPD in nonsmokers older adults, having a universe of 14,920 patients. The primary risk factor to trigger the development of COPD was secondhand smoking. The study defined the most common risk factors that currently trigger COPD development among nonsmokers and provided an insight into the potential clinical differences between nonsmokers and smokers.

Epidemiology and risk factors of chronic obstructive pulmonary disease in Suzhou: a population-based cross-sectional study

Background

The prevalence of chronic obstructive pulmonary disease (COPD) in Suzhou remains still unknown. The aim of this study was to quantify the disease burden and assess the risk factors of COPD.

Methods

This was a population-based, cross-sectional study of adults aged 40 years and older in Suzhou. A total of 4,864 adults were identified from June 2018 to December 2018 and 4,725 adults were finally recruited. Subjects underwent post-bronchodilator spirometry and were diagnosed according to the 2018 Global Initiative for Chronic Obstructive Lung Disease (GOLD).

Results

The data from 4,725 adults were ultimately included in the final analysis. The overall prevalence of COPD in subjects aged 40 and older was 12.4%, while it was 12.3% in men and 12.5% in women. Risk factors identified by multivariable logistic analysis were age (P<0.05, OR =2.29, 95% CI, 1.83–2.88) and underweight (BMI <18.5 kg/m²) (P<0.05, OR =1.57, 95% CI, 1.01–2.44). COPD patients also displayed weaker grip strength (P<0.001). Approximately half (50.7%) the COPD patients were asymptomatic, and compared with asymptomatic COPD patients, symptomatic COPD patients were older (69.5 vs. 67.2, P<0.05), smoked more frequently (12.1 vs. 7.1 pack year, P<0.05), had a more severe GOLD stage (stage I 27.0% vs. 39.4%, stage II 50.2% vs. 46.8%, stage III 17.0% vs. 11.1%, stage IV 5.8% vs. 2.7%, P<0.05), and a worse lung function index (FEV₁, FVC, PEF, FEF₂₅, FEF₅₀, FEF₇₅, FEF₂₅₇₅) (P<0.05).

Conclusions

COPD was found to be highly prevalent in adults aged 40 years and older in Suzhou. Age and underweight were major risk factors of COPD. Half of the COPD patients were asymptomatic, and displayed decreased lung function upon the onset of respiratory symptoms. Therefore, spirometry screening is essential for the early detection and management of COPD.

Development and validation of a prediction model for airflow obstruction in older Chinese: Guangzhou Biobank Cohort Study

OBJECTIVE

To develop and validate a prediction model for airflow obstruction (AO) in older Chinese.

METHODS

DESIGN

Multivariable logistic regression analysis in large population cohort of Chinese aged ≥50 years.

PARTICIPANTS

Model development: 8762 Chinese aged ≥50 years were selected from the early phase recruits to the Guangzhou Biobank Cohort Study (GBCS) (recruited from September 2003 to May 2006). Internal validation: 100 bootstrap samples drawn with replacement from the development sample. External validation: 8395 Chinese aged ≥50 years from later phase GBCS (recruited from September 2006 to January 2008).

OUTCOMES

AO was defined by a forced expiratory volume in 1 s/forced vital capacity ratio < lower limits of normal.

RESULTS

839 (9.6%) and 764 (9.1%) individuals had AO in the development and temporal validation samples respectively. The predictors in the prediction model included sex, age, body mass index groups, smoking status, presence of respiratory symptoms, and history of asthma. Model development and validation was stratified by sex. Model performance including calibration (calibration-in-the-large -0.017 vs. -0.157; and calibration slope 0.88 vs. 1.02), discrimination (C-statistic 0.72 vs. 0.63 with 95% confidence interval 0.69-0.75 vs. 0.62-0.73) and clinical usefulness (decision curve analysis) in the external temporal validation sample were more satisfactory in men than that in women. Prediction models with risk thresholds (13% in men and 7% in women) and easy-to-use nomograms were developed to assess the probability of AO.

CONCLUSION

The diagnostic models based on readily available epidemiologic and clinical information with satisfactory performance can assist physicians to identify older individuals at high risk of AO and may improve the efficiency of spirometry for active case finding. Further validation beyond the Chinese population is warranted.

Clearing the Smoke Screen: Smoking, Alcohol Consumption, and Stress Management Techniques among Canadian Long-Term Care Workers

BACKGROUND

Currently, there is abundant research indicating that smoking and alcohol consumption have significant impacts on morbidity and mortality, though little is known about these behaviors among Canadian health care workers. The objective of this study was to examine health and coping behaviors, such as smoking and alcohol consumption as well as stress management techniques, among health care workers consisting of gendered, racialized, and immigrant employees.

METHODS

Drawing on a single-case, mixed-methods study in Ontario, Canada, this paper presents under-researched data about smoking practices, alcohol consumption, and stress management techniques among health care workers in labor-intensive, high-stress, high-turnover environments. In particular, it identifies the various mechanisms for maintaining health and well-being.

RESULTS

The findings suggest that 7.7% of survey respondents reported smoking while 43.4% reported alcohol consumption, which were reported more frequently among immigrants than among non-immigrants. Participants also reported health-promoting activities in face-to-face interviews, such as mindful breathing techniques and drawing upon social support, while a few respondents reported alcohol consumption to specifically cope with sleep disturbances and job stress.

CONCLUSIONS

Although smoking and alcohol consumption were both connected with coping strategies and leisure, they were predominant in immigrant groups compared to non-immigrant groups.

Increased Long-Term Risks of Occupational Diseases in Homecare Nurses: A Nationwide Population-Based Retrospective Cohort Study

Background: The work of homecare nurses is different from that of general hospital nurses; therefore, it is necessary to understand the risks of occupational diseases in homecare nurses. Materials and Methods: In this retrospective cohort research conducted from 2000 to 2013, nursing staff comprised the sample obtained from the National Health Insurance Research Database. Nursing staff were subgrouped according to practice site into homecare, medical center, regional hospital, and local community hospital nurses. The control group included 4,108 subjects. Results: The risk of severe kidney disease was higher in homecare nurses than in medical center nurses (hazard ratio [HR]: 7.3, 95% confidence interval [CI]: 2.45-21.78) and regional hospital nurses (HR: 3.30, 95% CI: 1.37-7.96). The risk of severe liver disease was higher in homecare nurses than in medical center nurses (HR: 1.92, 95% CI: 1.10-3.35) and regional hospital nurses (HR: 2.06, 95% CI: 1.17-3.62). Conclusions: The prevalence of occupational diseases was higher in homecare nurses than in noncaregivers. The correlation between different practice environments and disease prevalence rates revealed that various types of nurses can be ranked in the following order based on the prevalence of the aforementioned diseases: homecare nurses > local community hospital nurses > regional hospital nurses > medical center nurses.

Assessment of comorbidities and prognosis in patients with COPD diagnosed with the fixed ratio and the lower limit of normal: a systematic review and meta-analysis

BACKGROUND

Currently, the diagnosis of chronic obstructive pulmonary disease (COPD) is not uniform, COPD guidelines recommend fixed ratio (FR), whereas ATS and ERS define airflow obstruction based on lower limit of normal (LLN). We aim to determine if there is difference between the two diagnostic criteria for morbidity, mortality, exacerbation.

METHODS

Four databases and all relevant studies from the references were searched from inception to June 25, 2019, to find studies that described the rate of comorbidity, the exacerbation rates, mortality in COPD patients. Data analysis was performed using STATA/SE 14.0 and followed the standard of Cochrane Collaboration. A sensitivity analysis was performed to find the source of heterogeneity.

RESULTS

Thirteen studies and 154,447 participants were finally included in this meta-analysis. The 11 cohort studies and 2 cross-sectional studies were all high-quality. Patients with airflow limitation according to either FR or LLN had higher mortality (HR_FR+/LLN- = 1.27, 95% CI = 1.14-1.42; HR_FR-/LLN+ = 1.83, 95% CI = 1.17-2.86) than those who met neither criteria. When compared with the FR-/LLN- criteria, those who met the FR criteria were more likely to exacerbate (HR _FR+/LLN- = 1.64, 95% CI = 1.09-2.46; HR _FR-/LLN+ = 1.58, 95% CI = 0.70-3.55). The meta-analysis for comorbidities showed no significant difference between patients who met neither criteria and those who met LLN or FR criteria.

CONCLUSION

The patients with airflow limitations according to FR were more likely to exacerbate than those with LLN only. Patients that met either FR or LLN were more likely to have higher mortality than FR-/LLN-. There was no difference between the FR+/LLN- and FR-/LLN+ groups for the occurrence of comorbidities.

Suppressive effect of environmental tobacco smoke on murine Th2 cell-mediated nasal eosinophilic inflammation

Background

Environmental tobacco smoke (ETS) exposure is recognized as a risk factor for the development of various respiratory diseases.

Objective

In this study, the effect of ETS on allergen-immunized and allergen-specific Th2 cell-transferred murine eosinophilic inflammation models and that of cigarette smoke extract (CSE) and nicotine on allergen-induced Th2 cell proliferation and interleukin (IL)-4 production were investigated.

Methods

Ovalbumin (OVA)-immunized and OVA-specific Th2 cell-transferred BALB/c mice were exposed to ETS and were challenged with OVA. Then, the number of inflammatory cells in the nasal mucosa and nasal hyperresponsiveness (NHR) were assessed. The effects of CSE and nicotine on the allergen-induced proliferative response of and IL-4 production by Th2 cells were determined in vitro.

Results

In OVA-immunized and Th2 cell-transferred mice, allergen-induced NHR and nasal eosinophil infiltration were significantly suppressed by ETS exposure, whereas the accumulation of neutrophils was rather enhanced. Allergen-specific Th2 cell proliferation and IL-4 production were inhibited by coculture with CSE. The same effects were induced by nicotine, though the effect on proliferation was relatively weak.

Conclusion

Regardless of its harmful effect, ETS suppresses NHR, probably through the inhibition of Th2 cell responses.

The protective effects of thymoquinone on lung damage caused by cigarette smoke

Chronic obstructive pulmonary disease (COPD) is characterized by systemic inflammation that usually is caused by exposure to noxious particles or gases. Thymoquinone (TQ) prevents the production of inflammatory mediators, such as thromboxane B2 and leukotriene, by altering arachidonic acid metabolism. We investigated the preventive and curative effects of TQ on lung damage in rats caused by cigarette smoke (CS). We used 50 adult male rats, 30 of which were exposed to CS every day for 3 months. TQ in dimethylsulfoxide (DMSO) was administered intraperitoneally (i.p.) every day to ten animals to investigate the protective effects of TQ, and to ten other animals during the last 21 days to investigate the curative effect. Ten rats received saline for the last 21 days. Ten subjects were untreated controls. Ten controls that were not exposed to CS received TQ for the last ten days. Serum IL-8, IL-6, IL-1β and MMP-9 levels were measured using ELISA. IL-1β and IL-8 levels were elevated in the group exposed to CS compared to controls. IL-8 levels were decreased in the group that received only TQ compared to controls, which indicated the anti-inflammatory effect of TQ. The apoptotic index (AI) was increased in all groups that were exposed to CS compared to controls. The AI index was decreased in the group that received TQ for the last 21 days compared to the other CS groups. AI was increased in the group that received TQ daily compared to the other CS groups. Our findings indicate that TQ exerts curative effects for the inflammation caused by CS and may prevent apoptosis if administered in appropriate doses; however, long term TQ or DMSO exposure may produce cumulative toxic effects.

Objective secondhand smoke exposure in chronic obstructive pulmonary disease patients without active smoking: the U.S. National Health and Nutrition Examination Survey (NHANES) 2007-2012

Background

Secondhand smoke (SHS) may be related to worse outcomes in chronic obstructive pulmonary disease (COPD), but the reported SHS prevalence in different studies varied from 27% to 65% and the effects of SHS are still questionable among these patients. The study aims were to estimate the objective SHS prevalence and explore the SHS impact on outcomes among COPD patients without active smoking.

Methods

A cross-sectional design combined with longitudinal death outcome. We selected COPD patients over 40 years old based on the spirometry from National Health and Nutrition Examination Survey (2007–2012), and used the tobacco-specific biomarkers [cotinine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanonol] to determine exposure statuses (active smoking, SHS exposure, or no smoke exposure). Then we estimated the short-term (past 2–4 days) and medium-term (past 6–12 weeks) SHS prevalence among 334 patients without active smoking. Weighted multiple regressions were performed to assess the associations between medium-term SHS exposure and outcomes (symptoms, health status, medical institution visits, and death).

Results

Among the patients without active smoking, the objective prevalence rates of short-term and medium-term SHS were 66.65% [95% confidence interval (CI), 59.63–73.67%] and 34.91% (95% CI, 28.86%–40.96%), respectively. Medium-term SHS exposure showed a significant effect (odds ratio, 3.57; 95% CI, 1.22–10.40) on more chronic coughing after adjusting for the covariates and indicated a trend of unadjusted increasing death risk (log-rank test, P=0.01).

Conclusions

Among COPD patients without active smoking, both short-term and medium-term SHS exposure are prevalent. Chronic cough may be the most susceptible patient-centred outcome related to medium-term SHS exposure. The crude longitudinal trend of elevated death risk associated with medium-term SHS exposure deserves further study.

Indoor PM2.5, tobacco smoking and chronic lung diseases: A narrative review

The lung is one of the most important organs exposed to environmental agents. People spend approximately 90% of their time indoors, and risks to health may thus be greater from exposure to poor air quality indoors than outdoors. Multiple indoor pollutants have been linked to chronic respiratory diseases. Environmental tobacco smoke (ETS) is known as an important source of multiple pollutants, especially in indoor environments. Indoor PM_2.5 (particulate matter with aerodynamic diameter < 2.5 μm) was reported to be the most reliable marker of the presence of tobacco smoke. Recent studies have demonstrated that PM_2.5 is closely correlated with chronic lung diseases. In this paper, we reviewed the relationship of tobacco smoking and indoor PM_2.5 and the mechanism that underpin the link of tobacco smoke, indoor PM_2.5 and chronic lung diseases.

REALizing and improving management of stable COPD in China: a multi-center, prospective, observational study to realize the current situation of COPD patients in China (REAL) - rationale, study design, and protocol

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is the fifth leading cause of death in China with a reported prevalence of 8.2% people aged ≥40 years. It is recommended that Chinese physicians follow Global Initiative for Chronic Obstructive Lung Disease (GOLD) and national guidelines, yet many patients with COPD in China remain undiagnosed. Furthermore, missed diagnoses and a lack of standardized diagnosis and treatment remain significant problems. The situation is further complicated by a lack of large-scale, long-term, prospective studies of real-world outcomes, including exacerbation rates, disease severity, efficacy of treatment, and compliance of COPD patients in China.

METHODS/DESIGN

The REALizing and improving management of stable COPD in China (REAL) study is a 52-week multi-center, prospective, observational trial. REAL aims to recruit approximately 5000 outpatients aged ≥40 years with a clinical diagnosis of COPD per GOLD 2016. Outpatients will be consecutively recruited from approximately 50 tertiary and secondary hospitals randomly selected across six geographic regions to provide a representative population. Patients will receive conventional medical care as determined by their treating physicians. The primary objective is to evaluate COPD patient outcomes including lung function, health status, exacerbations, hospitalization rate, and dyspnea following 1 year of current clinical practice. Secondary objectives are to assess disease severity, treatment patterns, adherence to medication, and associated risk factors. Data will be collected at two study visits, at patients' usual care visits, and by telephone interview every 3 months.

DISCUSSION

Knowledge of COPD among physicians in China is poor. The REAL study will provide reliable information on COPD management, outcomes, and risk factors that may help improve the standard of care in China. Patient recruitment began on 30 June 2017 and the estimated primary completion date is 30 July 2019.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03131362. Registered on 20 March 2017.

Does passive smoking at home lead to depression among older people in China?

BACKGROUND

This paper was carried out based on two motivations: (a) prior studies achieved mixed results regarding the effect of passive smoking on depression; and (b) studies on the impacts of passive smoking usually neglect effects on older people. In our paper, we studied the causal effect of passive smoking at home on depression among older people aged 60 years and older in China with a longitudinal study.

METHODS

In assessing the causal relationship, we developed a fixed-effects instrumental variable method using an exogenous variable-health consciousness and the smoking status of parents-as instruments of smoking status. We used data from the China Health and Retirement Longitudinal Study (CHARLS), which provides a national, high-quality, and longitudinal household survey of people aged 45 years and older.

RESULTS

Our empirical results reveal that passive smoking at home increased the depressive symptoms of older people, regardless of their smoking status. Moreover, the impact of passive smoking on depression is larger for nonsmokers than smokers. Additionally, the health consciousness and smoking status of parents are effective instrumental variables.

CONCLUSIONS

This paper calls for governments and medical institutions to pay more attention to the health of older people and their need for healthy living environments.

All-cause and cause-specific mortality from restrictive and obstructive spirometric patterns in Chinese adults with and without dyspnea: Guangzhou Biobank Cohort Study

OBJECTIVE

To study whether abnormal spirometric patterns were associated with differential mortality in Chinese adults with and without dyspnea.

METHODS

Guangzhou Biobank Cohort Study (GBCS) participants were classified by spirometric patterns and presence of dyspnea into 6 groups: normal spirometry (NS), restriction on spirometry (ROS) and airflow obstruction (AO), each with and without dyspnea. Adjusted hazard ratios (aHRs) were calculated for mortality using Cox models.

RESULTS

Among 16777 subjects, 1595 (9.5%) had ROS, 1036 (6.2%) had AO and 1009 (6.0%) had dyspnea. A total of 1993 deaths (11.9%) occurred during 11-year follow-up. Using NS without dyspnea as reference, NS with dyspnea was significantly associated with increased cardiovascular mortality risk (aHRs 1.61 (95% confidence interval (CI) 1.18-2.19); ROS with and without dyspnea were associated with increased risks of all-cause (aHRs 1.46 (95% CI 1.28-1.66) and 1.81 (95% CI 1.33-2.47)) and cardiovascular mortality (aHRs 1.89 (95% CI 1.55-2.31) and 1.85 (95% CI 1.12-3.03)), but not of lung cancer mortality (aHRs 1.33 (95% CI 0.91-1.94) and 1.35 (95% CI 0.49-3.70)); AO with and without dyspnea were associated with increased risks of all-cause (aHRs 1.59 (95% CI 1.36-1.86) and 2.36 (95% CI 1.77-3.15)), cardiovascular (aHRs 1.43 (95% CI 1.08-1.90) and 1.61 (95% CI 0.91-2.82)) and lung cancer mortality (aHRs 1.91 (95% CI 1.29-2.84) and 3.01 (95% CI 1.46-6.23)). These associations did not vary by sex or smoking status (all P-values for interaction >0.05).

CONCLUSION

Both ROS and AO, with and without dyspnea, were associated with increased all-cause and cardiovascular disease mortality. The increased risk of all-cause was greater and that of cardiovascular mortality was lower for AO than ROS. AO showed significantly increased risk of lung cancer but ROS did not. (272 words).

Receptor for advanced glycation end-products and environmental exposure related obstructive airways disease: a systematic review

Background

Our group has identified the receptor for advanced glycation end-products (RAGE) as a predictor of World Trade Center particulate matter associated lung injury. The aim of this systematic review is to assess the relationship between RAGE and obstructive airways disease secondary to environmental exposure.

Methods

A comprehensive search using PubMed and Embase was performed on January 5, 2018 utilising keywords focusing on environmental exposure, obstructive airways disease and RAGE and was registered with PROSPERO (CRD42018093834). We included original human research studies in English, focusing on pulmonary end-points associated with RAGE and environmental exposure.

Results

A total of 213 studies were identified by the initial search. After removing the duplicates and applying inclusion and exclusion criteria, we screened the titles and abstracts of 61 studies. Finally, 19 full-text articles were included. The exposures discussed in these articles include particulate matter (n=2) and cigarette smoke (n=17).

Conclusion

RAGE is a mediator of inflammation associated end-organ dysfunction such as obstructive airways disease. Soluble RAGE, a decoy receptor, may have a protective effect in some pulmonary processes. Overall, RAGE is biologically relevant in environmental exposure associated lung disease. Future investigations should focus on further understanding the role and therapeutic potential of RAGE in particulate matter exposure associated lung disease.

RAGE is biologically relevant in environmental exposure associated lung disease. Future investigations should focus on further understanding the role and therapeutic potential of RAGE in particulate matter exposure associated lung diseasehttp://ow.ly/gfZz30o7otU