Respiratory symptoms and pulmonary function in an elderly nonsmoking population

Impaired pulmonary function and associated factors in the elderly with tuberculosis on admission: a preliminary report

BACKGROUND

Pulmonary tuberculosis (TB) can impair pulmonary function (PF), especially in the elderly. The risk factors associated with the severity of PF impairment in the elderly with pulmonary TB remain unclear. Hence, this retrospective study aimed to address this issue to help improve the management of TB in the elderly population.

METHODS

From January 2019 to February 2022, the elderly who were admitted to our hospital for pulmonary TB and underwent PF testing were included in this analysis. The forced expiratory volume in one second percent of predicted (FEV1% predicted) and clinical characteristics were collected and analyzed retrospectively. The extent of impaired PF was then categorized based on the FEV1% predicted and classified as grade 1-5. Logistic regression analysis was used to analyze the risk factors for impaired PF.

RESULTS

A total of 249 patients who met the enrollment criteria were included in this analysis. According to the results of FEV1% predicted, all patients were classified as grade 1 (n = 37), grade 2 (n = 46), grade 3 (n = 55), grade 4 (n = 56), or grade 5 (n = 55). Statistical analysis showed that albumin (adjusted odds ratio (aOR) = 0.928, P = 0.013), body mass index (BMI) < 18.5 kg/m² (aOR = 4.968, P = 0.046), lesion number ≥ 3 (aOR = 4.229, P < 0.001), male (aOR = 2.252, P = 0.009), respiratory disease (aOR = 1.669, P = 0.046), and cardiovascular disease (aOR = 2.489, P = 0.027) were related to the impairment of PF.

CONCLUSIONS

PF impairment is common in the elderly with pulmonary TB. The male sex, BMI < 18.5 kg/m², lesion number ≥ 3, hypoproteinemia, and respiratory and cardiovascular comorbidities were identified as risk factors for significant PF impairment. Our findings highlight the risk factors associated with PF impairment, which may be helpful to improve the current management of pulmonary TB in the elderly to save their lung function.

The predictors of the pulmonary function in community-dwelling older adults

Purpose: The aim of the study was to observe the relationship between age, body mass index (BMI), physical activity, and kyphosis angle parameters with respiratory function capacity in community-dwelling older adults and to determine the main predictor. Methods: A prospective cross-sectional study was carried out with 70 older adults. Physical activity level was questioned with the Physical Activity Scale for Elderly (PASE). Thoracic kyphosis degrees were measured with a digital inclinometer. Pulmonary Function Test (PFT) was used to measure pulmonary function capacity. The correlation between age, BMI, PASE, thoracic kyphosis angle with parameters of PFT measurement was analyzed. In addition, a linear multivariate regression model was built to determine the main predictor. Results: The mean age of the participants was 69.88±4.52 years. There was a low degree but a statistically significant positive correlation between BMI and FEV1 (r=0.258,p

Tobacco Use and Secondhand Smoke Exposure Among Older Adults in India

Objectives: Current tobacco use (CTU) and secondhand smoke (SHS) exposure among older adults in India (≥60 years) are prevalent in India and indicate the importance of addressing associated factors. Methods: Pooled Global Adult Tobacco Survey India 2009-2010 and 2016-2017 data (n = 17,299) for older adults examined prevalence of CTU and SHS exposure at home and/or in public places and associated socioeconomic and demographic correlates. Results: CTU among older adults in India was 44.6%, and SHS exposure at home and public places were 20.0% and 30.0%, respectively. Men, younger age-group, rural, lower education, lower wealth index, and lower knowledge were independently associated with CTU. Men, rural, lower education, lower wealth index, CTU, and lower knowledge were independently associated with SHS exposure at home. Men, younger age, and rural residence were associated with SHS exposure in public places. Conclusion: CTU and SHS exposure among older adults in India suggest targeted interventions to address associated social and demographic factors.

Exposure to second-hand tobacco smoke and respiratory symptoms in non-smoking adults: cross-sectional data from the general population of Telemark, Norway

Background

In Norway, data on the association between second-hand tobacco smoke (SHS) exposure at home and respiratory symptoms in adults are limited.

Methods

We assessed the association between self-reported exposure to SHS and the prevalence of respiratory symptoms among never-smokers aged 16 to 50 years from the general population who were included in a cross-sectional population-based study in Telemark County, Norway. Logistic regression analysis was used to estimate the odds ratios of symptoms among 8850 never-smokers who provided an affirmative response to questions regarding SHS; 504 (5.7%) of these reported that they lived in a home with daily or occasional indoor smoking.

Results

Productive cough and nocturnal dyspnoea were statistically associated with daily SHS exposure (ORs 1.5 [95% CI 1.04–2.0] and 1.8 [1.2–2.7], respectively). In analyses stratified by gender, nocturnal dyspnoea was associated with SHS among women (OR 1.8 [1.1–3.1]), but not among men (OR 0.93 [0.49–1.8]). Symptoms were not associated with occasional SHS exposure in the entire group, but infrequent exposure among men only was associated with increased prevalence of chronic cough; (OR 1.6; [1.04–2.6]) and was negatively associated with wheeze; (OR 0.44 [0.21–0.92)].

Conclusions

Daily SHS exposure in private homes was associated with productive cough and nocturnal dyspnoea. Our results suggest that preventive measures may be needed to reduce the respiratory effects of SHS at home.

Trial registration

ClinicalTrials.gov Identifier: NCT02073708 Registered February 27. 2014.

Association between second-hand smoke and psychological well-being amongst non-smoking wageworkers in Republic of Korea

BACKGROUND

Worldwide, exposure to second-hand smoke (SHS) has been responsible for more than 0.6 million deaths and 10.9 million disability-adjusted life years (DALYS) lost in never smokers in 2004. The world health organization (WHO) reported smoking-related death of 58,000 per year in South Korea. There is recent emerging evidence of the associations of SHS exposure with anxiety or depression and poor mental health. Although exposure to second-hand smoke (SHS) has been associated with various physical health conditions and mental health, we are unaware of any studies examining its association with psychological well-being as mental factor. This study aimed to investigate the association between self-reported exposure to SHS and well-being among non-smoking wageworkers.

METHODS

The Third Korean Working Conditions Survey (KWCS, 2011) was conducted on a representative sample of economically active population aged 15 years or over, who were either employees or self-employed at the time of interview. In this study, after removing inconsistent data, 19,879 non-smoking wageworkers among 60,054 workers were participated. Psychological well-being was measured through the WHO-Five Well-Being Index (1998 version). Univariate and multiple logistic regression models were used to examine the association of SHS exposure with psychological well-being.

RESULTS

The unadjusted OR of poor psychological well-being (OR: 1.594, 95 % CI: 1.421-1.787) was significantly higher for SHS exposure group compared to non-exposure group. Multiple logistic regression analysis results indicated that these relationships were still significant after adjusting for potential confounders (adjusted OR: 1.330, 95 % CI: 1.178-1.502).

CONCLUSIONS

Exposure to SHS was associated with poor well-being measured by the WHO-5 well-being index, indicating the importance of reducing SHS exposure at the workplace for psychological well-being amongst non-smoking wageworkers.

Respiratory health outcomes and air pollution in the Eastern Mediterranean Region: a systematic review

Exposure to air pollution can cause detrimental health and be an economic burden. With newly developed equipment, monitoring of different air pollutants, identifying the sources, types of air pollutants and their corresponding concentrations, and applying mitigation intervention techniques became a crucial step in public health protection. Countries in the Eastern Mediterranean Region (EMR) are highly exposed to dust storms, have high levels of particulate matter (PM) concentrations, and have a unique climatic as well as topographic and socio-economic structure. This is the first study conducted to systemically and qualitatively assess the health impacts of air pollution in the EMR, identify susceptible populations, and ascertain research and knowledge gaps in the literature to better inform decisions by policy makers. We screened relevant papers and reports published between 2000 and 2014 in research databases. A total of 36 published studies met the inclusion criteria. A variety of indoor and outdoor exposures associated with various acute and chronic respiratory health outcomes were included. Respiratory health outcomes ranged in severity, from allergies and general respiratory complaints to lung cancer and mortality. Several adverse health outcomes were positively associated with various indoor/outdoor air pollutants throughout the EMR. However, epidemiological literature concerning the EMR is limited to a few studies in a few countries. More research is needed to elucidate the health outcomes of air pollution. Standardized reliable assessments on the national level for various air pollutants in different regions should be implemented and made publically available for researchers to utilize in their research. Moreover, advancing and utilizing more sound epidemiological designs and studies on the effect of air pollution on the respiratory health outcomes is needed to portray the actual situation in the region.

SmokeHaz: Systematic Reviews and Meta-analyses of the Effects of Smoking on Respiratory Health

BACKGROUND

Smoking tobacco increases the risk of respiratory disease in adults and children, but communicating the magnitude of these effects in a scientific manner that is accessible and usable by the public and policymakers presents a challenge. We have therefore summarized scientific data on the impact of smoking on respiratory diseases to provide the content for a unique resource, SmokeHaz.

METHODS

We conducted systematic reviews and meta-analyses of longitudinal studies (published to 2013) identified from electronic databases, gray literature, and experts. Random effect meta-analyses were used to pool the findings.

RESULTS

We included 216 articles. Among adult smokers, we confirmed substantially increased risks of lung cancer (risk ratio (RR), 10.92; 95% CI, 8.28-14.40; 34 studies), COPD (RR, 4.01; 95% CI, 3.18-5.05; 22 studies), and asthma (RR, 1.61; 95% CI, 1.07-2.42; eight studies). Exposure to passive smoke significantly increased the risk of lung cancer in adult nonsmokers and increased the risks of asthma, wheeze, lower respiratory infections, and reduced lung function in children. Smoking significantly increased the risk of sleep apnea and asthma exacerbations in adult and pregnant populations, and active and passive smoking increased the risk of tuberculosis.

CONCLUSIONS

These findings have been translated into easily digestible content and published on the SmokeHaz website.

Effect of Exposure to Second-Hand Smoke on the Quality of Life: A Nationwide Population-Based Study from South Korea

Background

Although exposure to second-hand smoke (SHS) has been associated with various medical conditions, only limited data are available on its association with health-related quality of life (HRQOL), particularly data obtained with the EQ-5D or EQ visual analogue scale (VAS).

Methods

This cross-sectional study evaluated 10,532 adult never-smokers who participated in the fifth Korea National Health and Nutrition Examination Survey. By using linear regression models to adjust for possible confounders and incorporating survey weights in analyses, the association between exposure to SHS and HRQOL—measured with the EQ-5D index and the EQ-VAS score—was evaluated. Data were further stratified by the amount of exposure time.

Results

After weighted analysis and adjustment, exposure to SHS was significantly associated with lower measures on the EQ-5D index (β = −0.007, P = 0.005) and EQ-VAS score (β = −1.936, P < 0.001). When comparing the unexposed group with the groups exposed <2h/day and ≥2h/day, exposure to a longer duration of SHS was significantly associated with lower scores on the EQ-5D index and the EQ-VAS score.

Conclusion

In conclusion, exposure to SHS was associated with reduced HRQOL measured by the EQ-5D index and EQ-VAS score, revealing a dose-response relationship.

Tobacco use among designated air pollution victims and its association with lung function and respiratory symptoms: a retrospective cross-sectional study

OBJECTIVES

We sought to elucidate the long-term association of tobacco use and respiratory health in designated pollution victims with and without obstructive pulmonary defects.

DESIGN

A retrospective cross-sectional study.

SETTING

The register of pollution victims in Kurashiki, Japan.

PARTICIPANTS

730 individuals over 65 years of age previously diagnosed with pollution-related respiratory disease. Patients were classified into four groups according to their smoking status and whether they had obstructive pulmonary disease. We then compared the prevalence of respiratory symptoms and lung function over time between groups.

PRIMARY OUTCOME MEASURES

Spirometry was performed and a respiratory health questionnaire completed in the same season each year for up to 30 years.

RESULTS

Rates of smoking and respiratory disease were high in our sample. Although respiratory function in non-smoking patients did not completely recover, the annual rate of change in lung function was within the normal range (p<0.01). However, smokers had worse lung function and were more likely to report more severe pulmonary symptoms (p<0.01).

CONCLUSIONS

Patients' respiratory function did not fully recover despite improved air quality. Our results suggest that, in the context of exposure to air pollution, tobacco use causes additional loss of lung function and exacerbates respiratory symptoms.

Longitudinal study of respiratory function and symptoms in a non-smoking group of long-term officially-acknowledged victims of pollution-related illness

BACKGROUND

Air pollution is known to be a leading cause of respiratory symptoms. Many cross-sectional studies reported that air pollution caused respiratory disease in Japanese individuals in the 1960s. Japan has laws regulating air pollution levels and providing compensation for victims of pollution-related respiratory disease. However, long-term changes in respiratory function and symptoms in individuals who were exposed to air pollution in the 1960s have not been well studied. This study aimed to investigate longitudinal respiratory function and symptoms in older, non-smoking, long-term officially-acknowledged victims of pollution-related illness.

METHODS

The study included 563 officially-acknowledged victims of pollution-related illness living in Kurashiki, Okayama who were aged ≥ 65 years in 2009. Data were retrospectively collected from yearly respiratory symptom questionnaires and spirometry examinations conducted from 2000 to 2009.

RESULTS

Respiratory function declined significantly from 2000 to 2009 (p < 0.01), but the mean annual changes were relatively small. The change in mean vital capacity was -40.5 ml/year in males and -32.7 ml/year in females, and the change in mean forced expiratory volume in 1 second was -27.6 ml/year in males and -23.9 ml/year in females. Dyspnea was the only symptom that worsened significantly from 2000 to 2009 in both sexes (males: p < 0.05, females: p < 0.01).

CONCLUSIONS

Our results suggest that the high concentrations of air pollutants around 1970 resulted in a decrease in respiratory function and an increase in respiratory symptoms in the study population. From 2000 to 2009, the mean annual changes in respiratory function were within the normal range, even though the severity of dyspnea worsened. The changes in respiratory function and symptoms over the study period were probably due to aging. The laws governing air pollution levels and providing compensation for officially-acknowledged victims of pollution-related illness in Japan may be effective for respiratory disease cause by pollution.

Role of IL-18 in second-hand smoke-induced emphysema

Chronic second-hand smoke (SHS) exposure comprises the main risk factor for nonsmokers to develop chronic obstructive pulmonary disease (COPD). However, the mechanisms behind the chronic inflammation and lung destruction remain incompletely understood. In this study, we show that chronic exposure of Sprague-Dawley rats to SHS results in a significant increase of proinflammatory cytokine IL-18 and chemokine (C-C motif) ligand 5 in the bronchoalveolar lavage fluid (BALF) and a significant decrease of vascular endothelial growth factor (VEGF) in the lung tissue. SHS exposure resulted in progressive alveolar airspace enlargement, cell death, pulmonary vessel loss, vessel muscularization, collagen deposition, and right ventricular hypertrophy. Alveolar macrophages displayed a foamy phenotype and a decreased expression of the natural inhibitor of IL-18, namely, IL-18 binding protein (IL-18BP). Moreover, IL-18 down-regulated the expression of VEGF receptor-1 and VEGFR receptor-2, and induced apoptosis in pulmonary microvascular endothelial cells in vitro. We also observed a trend toward increased concentrations of IL-18 in the BALF of patients with COPD. Our findings suggest that IL-18-mediated endothelial cell death may contribute to vascular destruction and disappearance in SHS-induced COPD. Moreover, IL-18 and IL-18BP are potential new targets for therapeutics.

Tobacco smoke induced COPD/emphysema in the animal model-are we all on the same page?

Chronic Obstructive Pulmonary Disease (COPD) is one of the foremost causes of death worldwide. It is primarily caused by tobacco smoke, making it an easily preventable disease, but facilitated by genetic α-1 antitrypsin deficiency. In addition to active smokers, health problems also occur in people involuntarily exposed to second hand smoke (SHS). Currently, the relationship between SHS and COPD is not well established. Knowledge of pathogenic mechanisms is limited, thereby halting the advancement of new treatments for this socially and economically detrimental disease. Here, we attempt to summarize tobacco smoke studies undertaken in animal models, applying both mainstream (direct, nose only) and side stream (indirect, whole body) smoke exposures. This overview of 155 studies compares cellular and molecular mechanisms as well as proteolytic, inflammatory, and vasoreactive responses underlying COPD development. This is a difficult task, as listing of exposure parameters is limited for most experiments. We show that both mainstream and SHS studies largely present similar inflammatory cell populations dominated by macrophages as well as elevated chemokine/cytokine levels, such as TNF-α. Additionally, SHS, like mainstream smoke, has been shown to cause vascular remodeling and neutrophil elastase-mediated proteolytic matrix breakdown with failure to repair. Disease mechanisms and therapeutic interventions appear to coincide in both exposure scenarios. One of the more widely applied interventions, the anti-oxidant therapy, is successful for both mainstream and SHS. The comparison of direct with indirect smoke exposure studies in this review emphasizes that, even though there are many overlapping pathways, it is not conclusive that SHS is using exactly the same mechanisms as direct smoke in COPD pathogenesis, but should be considered a preventable health risk. Some characteristics and therapeutic alternatives uniquely exist in SHS-related COPD.

Air pollution and chronic obstructive pulmonary disease

Limited data suggest that outdoor air pollution (such as ambient air pollution or traffic-related air pollution) and indoor air pollution (such as second-hand smoking and biomass fuel combustion exposure) are associated with the development of chronic obstructive pulmonary disease (COPD), but there is insufficient evidence to prove a causal relationship at this stage. It also appears that outdoor air pollution is a significant environmental trigger for acute exacerbation of COPD, leading to increasing symptoms, emergency department visits, hospital admissions and even mortality. Improving ambient air pollution and decreasing indoor biomass combustion exposure by improving home ventilation are effective measures that may substantially improve the health of the general public.

Acute exacerbations of chronic obstructive pulmonary disease in the emergency department

Chronic obstructive pulmonary disease (COPD) is a significant cause of morbidity and mortality worldwide. Acute exacerbations of COPD (AECOPDs) are a common presentation to emergency departments and are an important cause of respiratory failure. This article discusses the disease process and diagnosis of COPD and AECOPD. A further in-depth discussion is undertaken of evidence-based treatments, palliation, and disposition of patients who present to emergency departments with AECOPD.

Family history is a risk factor for COPD

BACKGROUND

Studies have shown that family history is a risk factor for COPD, but have not accounted for family history of smoking. Therefore, we sought to identify the effects of family history of smoking and family history of COPD on COPD susceptibility.

METHODS

We compared 821 patients with COPD to 776 control smokers from the Genetic Epidemiology of COPD (COPDGene) Study. Questionnaires captured parental histories of smoking and COPD, as well as childhood environmental tobacco smoke (ETS) exposure. Socioeconomic status was defined by educational achievement.

RESULTS

Parental history of smoking (85.5% case patients, 82.9% control subjects) was more common than parental history of COPD (43.0% case patients, 30.8% control subjects). In a logistic regression model, parental history of COPD (OR, 1.73; P < .0001) and educational level (OR, 0.48 for some college vs no college; P < .0001) were significant predictors of COPD, but parental history of smoking and childhood ETS exposure were not significant. The population-attributable risk from COPD family history was 18.6%. Patients with COPD with a parental history had more severe disease, with lower lung function, worse quality of life, and more frequent exacerbations. There were nonsignificant trends for more severe emphysema and airway disease on quantitative chest CT scans.

CONCLUSIONS

Family history of COPD is a strong risk factor for COPD, independent of family history of smoking, personal lifetime smoking, or childhood ETS exposure. Although further studies are required to identify genetic variants that influence COPD susceptibility, clinicians should question all smokers, especially those with known or suspected COPD, regarding COPD family history.

Passive smoking and chronic obstructive pulmonary disease: cross-sectional analysis of data from the Health Survey for England

OBJECTIVES

There is increasing evidence that passive smoking is associated with chronic respiratory diseases, but its association with chronic obstructive pulmonary disease (COPD) requires more study. In this cross-sectional analysis of data from 3 years of the Health Survey for England, the association between passive smoking exposure and risk of COPD is evaluated.

DESIGN

Cross-sectional analysis of the 1995, 1996 and 2001 Health Surveys for England including participants of white ethnicity, aged 40+ years with valid lung function data. COPD was defined using the lower limit of normal spirometric criteria for airflow obstruction. Standardised questions elicited self-reported information on demography, smoking history, ethnicity, occupation, asthma and respiratory symptoms (dyspnoea, chronic cough, chronic phlegm, wheeze). Passive smoking was measured by self-report of hours of exposure to cigarette smoke per week.

RESULTS

Increasing passive smoke exposure was independently associated with increased risk of COPD, with adjusted OR 1.05 (95% CI 0.93 to 1.18) for 1-19 h and OR 1.18 (95% CI 1.01 to 1.39) for 20 or more hours of exposure per week. Similar patterns (although attenuated and non-significant) were observed among never smokers. More marked dose-response relationships were observed between passive smoking exposure and respiratory symptoms, but the most marked effects were on the development of clinically significant COPD (airflow obstruction plus symptoms), where the risk among never smokers was doubled (OR 1.98 (95% CI 1.03 to 3.79)) if exposure exceeded 20 h/week.

CONCLUSION

This analysis adds weight to the evidence suggesting an association between passive smoking exposure and COPD.

Systematic review of the evidence relating FEV1 decline to giving up smoking

BACKGROUND

The rate of forced expiratory volume in 1 second (FEV1) decline ("beta") is a marker of chronic obstructive pulmonary disease risk. The reduction in beta after quitting smoking is an upper limit for the reduction achievable from switching to novel nicotine delivery products. We review available evidence to estimate this reduction and quantify the relationship of smoking to beta.

METHODS

Studies were identified, in healthy individuals or patients with respiratory disease, that provided data on beta over at least 2 years of follow-up, separately for those who gave up smoking and other smoking groups. Publications to June 2010 were considered. Independent beta estimates were derived for four main smoking groups: never smokers, ex-smokers (before baseline), quitters (during follow-up) and continuing smokers. Unweighted and inverse variance-weighted regression analyses compared betas in the smoking groups, and in continuing smokers by amount smoked, and estimated whether beta or beta differences between smoking groups varied by age, sex and other factors.

RESULTS

Forty-seven studies had relevant data, 28 for both sexes and 19 for males. Sixteen studies started before 1970. Mean follow-up was 11 years. On the basis of weighted analysis of 303 betas for the four smoking groups, never smokers had a beta 10.8 mL/yr (95% confidence interval (CI), 8.9 to 12.8) less than continuing smokers. Betas for ex-smokers were 12.4 mL/yr (95% CI, 10.1 to 14.7) less than for continuing smokers, and for quitters, 8.5 mL/yr (95% CI, 5.6 to 11.4) less. These betas were similar to that for never smokers. In continuing smokers, beta increased 0.33 mL/yr per cigarette/day. Beta differences between continuing smokers and those who gave up were greater in patients with respiratory disease or with reduced baseline lung function, but were not clearly related to age or sex.

CONCLUSION

The available data have numerous limitations, but clearly show that continuing smokers have a beta that is dose-related and over 10 mL/yr greater than in never smokers, ex-smokers or quitters. The greater decline in those with respiratory disease or reduced lung function is consistent with some smokers having a more rapid rate of FEV1 decline. These results help in designing studies comparing continuing smokers of conventional cigarettes and switchers to novel products.

An official American Thoracic Society public policy statement: Novel risk factors and the global burden of chronic obstructive pulmonary disease

RATIONALE

Although cigarette smoking is the most important cause of chronic obstructive pulmonary disease (COPD), a substantial proportion of COPD cases cannot be explained by smoking alone.

OBJECTIVES

To evaluate the risk factors for COPD besides personal cigarette smoking.

METHODS

We constituted an ad hoc subcommittee of the American Thoracic Society Environmental and Occupational Health Assembly. An international group of members was invited, based on their scientific expertise in a specific risk factor for COPD. For each risk factor area, the committee reviewed the literature, summarized the evidence, and developed conclusions about the likelihood of it causing COPD. All conclusions were based on unanimous consensus.

MEASUREMENTS AND MAIN RESULTS

The population-attributable fraction for smoking as a cause of COPD ranged from 9.7 to 97.9%, but was less than 80% in most studies, indicating a substantial burden of disease attributable to nonsmoking risk factors. On the basis of our review, we concluded that specific genetic syndromes and occupational exposures were causally related to the development of COPD. Traffic and other outdoor pollution, secondhand smoke, biomass smoke, and dietary factors are associated with COPD, but sufficient criteria for causation were not met. Chronic asthma and tuberculosis are associated with irreversible loss of lung function, but there remains uncertainty about whether there are important phenotypic differences compared with COPD as it is typically encountered in clinical settings.

CONCLUSIONS

In public health terms, a substantive burden of COPD is attributable to risk factors other than smoking. To prevent COPD-related disability and mortality, efforts must focus on prevention and cessation of exposure to smoking and these other, less well-recognized risk factors.

Alveolar macrophage recruitment and activation by chronic second hand smoke exposure in mice

Approximately 15% of cases of COPD occur in non-smokers. Among the potential risk factors for COPD in non-smokers is second-hand smoke (SHS) exposure. However, the Surgeon General reported in 2006 that the evidence linking second hand smoke and COPD is insufficient to infer a causal relationship, largely because current evidence does not establish a biological link. The goal of this study was to determine whether SHS exposure can induce alveolar macrophage recruitment and expression of activation markers that we have previously demonstrated in human smokers and in mouse models of emphysema. To achieve these goals, we studied mice exposed to an ambient mixture of predominantly [89%] sidestream smoke at increasing doses over 3 months. We found that second hand smoke exposure induced a dose-dependent increase in alveolar macrophage recruitment (mean +/- sd; 224,511 +/- 52,330 vs 166,152 +/- 47,989 macrophages/ml of bronchoalveolar lavage in smoke-exposed vs air-exposed controls at 3 months, p = 0.003). We also found increased expression of several markers of alveolar macrophage activation (PLA2g7, dkfzp434l142, Trem-2, and pirin, all p < 0.01 at 3 months) and increased lavage levels of two inflammatory mediators associated with COPD (CCL2 [MCP-1], 58 +/- 12 vs. 43 +/- 22 pg/ml, p = 0.03; and TNFalpha, 138 +/- 43 vs 88 +/- 78 pg/ml, p = 0.04 at 3 months). These findings indicate that second smoke exposure can cause macrophage recruitment and activation, providing a biological link between second-hand smoke exposure and the development of inflammatory processes linked to COPD.

Modeling approaches for estimating the dosimetry of inhaled toxicants in children

Risk assessment of inhaled toxicants has typically focused upon adults, with modeling used to extrapolate dosimetry and risks from lab animals to humans. However, behavioral factors such as time spent playing outdoors may lead to more exposure to inhaled toxicants in children. Depending on the inhaled agent and the age and size of the child, children may receive a greater internal dose than adults because of greater ventilation rate per body weight or lung surface area, or metabolic differences may result in different tissue burdens. Thus, modeling techniques need to be adapted to children in order to estimate inhaled dose and risk in this potentially susceptible life stage. This paper summarizes a series of inhalation dosimetry presentations from the U.S. EPA's Workshop on Inhalation Risk Assessment in Children held on June 8-9, 2006 in Washington, DC. These presentations demonstrate how existing default models for particles and gases may be adapted for children, and how more advanced modeling of toxicant deposition and interaction in respiratory airways takes into account children's anatomy and physiology. These modeling efforts identify child-adult dosimetry differences in respiratory tract regions that may have implications for children's vulnerability to inhaled toxicants. A decision framework is discussed that considers these different approaches and modeling structures including assessment of parameter values, supporting data, reliability, and selection of dose metrics.

Effects of environmental tobacco smoke on respiratory symptoms and pulmonary function

The aim of this study was to examine the effects of environmental tobacco smoke (ETS) on pulmonary function and respiratory symptoms. During periodic medical examination, 392 French nonsmokers responded to an interviewer-administered questionnaire. Then spirometry was performed to assess pulmonary function. All of the subjects were carefully examined by two occupational physicians. ETS exposure at the workplace was more common than this exposure at home (20% vs. 5%). ETS exposure was significantly associated with forced vital capacity (FVC; -3.16%; 95% CI: -5.67 to -0.64) and forced expiratory volume in 1s (FEV1; -2.90%; 95% CI: -5.59 to -0.23). Abnormal FVC results were significantly increased in exposed subgroup [odds ratio = 2.71 (95% CI: 1.09 to 6.75)]. We did not find any significant dose-response relationship between ETS exposure and lung function results. The effects of ETS exposure on respiratory symptoms and diseases (asthma, wheezing, chronic bronchitis, and dyspnea) were not significant. Thus, this study showed that there was a significant inverse association between exposure to ETS and pulmonary function. Even pulmonary function results inferior to the lower limit of normal may be possible. A stricter legislation against ETS is proposed.

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

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality in China, where the population is also exposed to high levels of passive smoking, yet little information exists on the effects of such exposure on COPD. We examined the relation between passive smoking and COPD and respiratory symptoms in an adult Chinese population.

METHODS

We used baseline data from the Guangzhou Biobank Cohort Study. Of 20 430 men and women over the age of 50 recruited in 2003-06, 15,379 never smokers (6497 with valid spirometry) were included in this cross-sectional analysis. We measured passive smoking exposure at home and work by two self-reported measures (density and duration of exposure). Diagnosis of COPD was based on spirometry and defined according to the GOLD guidelines.

FINDINGS

There was an association between risk of COPD and self-reported exposure to passive smoking at home and work (adjusted odds ratio 1.48, 95% CI 1.18-1.85 for high level exposure; equivalent to 40 h a week for more than 5 years). There were significant associations between reported respiratory symptoms and increasing passive smoking exposure (1.16, 1.07-1.25 for any symptom).

INTERPRETATION

Exposure to passive smoking is associated with an increased prevalence of COPD and respiratory symptoms. If this association is causal, we estimate that 1.9 million excess deaths from COPD among never smokers could be attributable to passive smoking in the current population in China. Our findings provide strong evidence for urgent measures against passive smoking in China.

Chronic airway diseases in adult life and childhood infections

BACKGROUND

Respiratory disorders in childhood may predispose to pulmonary disease in late adult life.

OBJECTIVES

The aim of this study was to evaluate the relationship between their effects in adult life and the characteristics of the respiratory system in childhood.

METHODS

A total of 10,224 parents and grandparents of students from 14 randomly selected primary schools in the city center were asked to answer questionnaires given to their children. 9,853 of 10,224 persons (the overall response rate was 96.3%) were eligible for analysis. In the questionnaire subjects were asked about respiratory system-related symptoms and characteristics.

RESULTS

Chronic cough [14.3 vs. 4.7%, OR 3.4 (2.6-4.4), p < 0.001], chronic bronchitis [35.3 vs. 11.8%, OR 4.0 (3.4-4.8), p < 0.001] and asthma [34.2 vs. 5.1%, OR 9.6 (8.0-11.5), p < 0.001] in the childhood respiratory infection group were more common than in the control group. Childhood respiratory infections were associated with an increased risk of asthma (OR 5.6, p < 0.001), chronic bronchitis (OR 2.3, p < 0.001) and chronic cough (OR 1.5, p < 0.001), after adjusting for possible confounding factors. In addition, the presence of dampness or visible mould, wall-to-wall carpets, pets at home and parents' smoking during childhood were associated with an increased risk of frequent childhood respiratory infections.

CONCLUSION

These results indicated that frequent respiratory infections during childhood might play an important role in the occurrence of chronic airway diseases in adult life. The removing of risk factors for frequent childhood respiratory infections may reduce the subsequent risk of chronic airway disease in late adult life.

Wheezing and lung function measured in subjects exposed to various levels of fine particles and polycyclic aromatic hydrocarbons

The main purpose of the study was to assess the occurrence of wheezing and lung function in non-smoking women exposed to various levels of fine particulate matter(FP) and polycyclic aromatic hydrocarbons (PAH). Out of the total study group, 152 women were included in the lower exposed group (PM2.5 ≤34.3μg/m3 or PAHs ≤ 22.9ng/ m3) and 96 persons in higher concentrations of both air pollutants (PM2.5>34.3μg/m3 and PAHs > 22.9ng/ m3). Except for FVC and FEV1, all lung forced ventilatory flows (PEFR, FEF25% FEF50%, FEF75%, FEF25−75%) were significantly lower in the higher exposed group. The findings suggest bronchoconstriction within the respiratory tract, which may be related to the exposure under study. This was consistent with a higher prevalence of wheezing in more exposed subjects. It was shown that higher levels of both pollutants increased the risk of wheezing by factor 5.6 (95% CI: 1.77–17.8) after accounting for potential confounders such as allergic diseases and exposure to ETS. This study suggests that pollutants in question may have the capacity to promote broncho-constriction and asthmatic symptoms, possibly by bronchial inflammation resulting from the exposure.

Secondhand smoke exposure, pulmonary function, and cardiovascular mortality

PURPOSE

Cardiovascular disease and obstructive lung disease are leading global causes of death. Despite this, the impact of secondhand smoke (SHS) exposure on pulmonary function and cardiovascular disease remains uncertain. Our goal was to elucidate the association between baseline SHS exposure and the risk of lung function decline and cardiovascular mortality over a period of nearly a decade.

METHODS

We used data from a longitudinal cohort study of 1,057 older adults to study the association between baseline SHS exposure and the risk of lung function decline and cardiovascular mortality. The effect of SHS exposure on cardiovascular mortality may be mediated by its influence on FEV1 and biological processes captured by measurement of FEV1. Alternatively, the effect of SHS may be mediated by baseline cardiovascular disease status, which reflects the combined effects of traditional cardiovascular risk factors. To correctly estimate the effect of SHS and FEV1 on cardiovascular mortality, we used marginal structural models (MSMs) that took into account the mediating effects of FEV1 and baseline cardiovascular disease in the causal pathway.

RESULTS

In longitudinal multivariate analyses, lifetime cumulative home and work SHS exposure were associated with a greater decline of FEV1 (-15 mL/s; 95% CI, -29 to -1.3 mL/s and -41 mL/s; 95% CI, -55 to -28 mL/s per 10-year cumulative exposure, respectively). Lifetime home SHS exposure was associated with a greater risk of cardiovascular mortality in both conventional multivariate analysis (HR, 1.10 per 10 years of exposure; 95% CI, 0.99 to 1.24) and the MSM for FEV1 (HR, 1.06; 95% CI, 0.95 to 1.19) and baseline cardiovascular disease (HR for subjects with no baseline cardiovascular disease, 1.39; 95% CI, 1.17 to 1.66).

CONCLUSIONS

Lifetime SHS exposure appears to result in a greater decline in lung function and risk of cardiovascular mortality, taking into account confounders and the mediating effect of FEV1 and baseline cardiovascular disease.

Elevated exhaled nitric oxide in newborns of atopic mothers precedes respiratory symptoms

RATIONALE

Exhaled nitric oxide (NO) is a well-known marker of established airway inflammation in asthma. Its role in the disease process before the onset of respiratory symptoms remains unclear.

OBJECTIVES

To examine whether elevated NO in newborns with clinically naive airways is associated with subsequent respiratory symptoms in infancy.

METHODS

We measured exhaled NO concentration and output after birth and prospectively assessed respiratory symptoms during infancy in a birth cohort of 164 unselected healthy neonates. We examined a possible association between NO and respiratory symptoms using Poisson regression analysis.

RESULTS

In infants of atopic mothers, elevated NO levels after birth were associated with increased risk of subsequent respiratory symptoms (risk ratio [RR], 7.5; 95% confidence interval [CI], 1.7-32.4 for each nl/s increase in NO output; p = 0.007). Similarly, a positive association between NO and symptoms was seen in infants of smoking mothers (RR, 6.6; 95% CI, 2.3-19.3; p = 0.001), with the strongest association in infants whose mothers had both risk factors (RR, 21.8; 95% CI, 5.8-81.3; p < 0.001).

CONCLUSIONS

The interaction of NO with maternal atopy and smoking on subsequent respiratory symptoms is present early in life. Clinically, noninvasive NO measurements in newborns may prove useful as a new means to identify high-risk infants. Future confirmation of a role for NO metabolism in the evolution of respiratory disease may provide an avenue for preventative strategies.

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

PURPOSE

Chronic obstructive pulmonary disease (COPD) is usually described as a disease of cigarette smoking. COPD is rarely considered in persons with no smoking history except in the context of another exposure. Accordingly, the disease has not been well characterized in these "never smokers."

METHODS

We evaluated airway obstruction (defined as forced expiratory volume in 1 second/forced vital capacity <0.70) in US adults aged 30 to 80 years interviewed in the Third National Health and Nutrition Examination Survey with valid spirometry who had never smoked. Previously described risk factors were examined for their association with obstruction in bivariate and multivariate analyses.

RESULTS

Never smokers represented 42% of the Third National Health and Nutrition Examination Survey population aged 30 to 80 years, with obstruction prevalence of 91 per 1000. Never smokers accounted for 4.56 million cases of obstruction, or 23% of the total burden. Among these obstructed never smokers, 19% reported a prior diagnosis of asthma alone, and 12.5% reported COPD (alone or with asthma), leaving 68.5% with no prior respiratory diagnosis. After adjustment for other factors, higher rates of obstruction were significantly associated with increasing age, male sex, lower body mass index, and a history of allergies.

CONCLUSIONS

Never smokers represent a significant proportion of airway obstruction in US adults. Only one fifth of obstruction in this group is explained by asthma. COPD may explain much of the remainder, although known risk factors were not explanatory in this dataset. Recommendations that lung health screening programs be limited to smokers should be reconsidered.

Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

BACKGROUND

Exposure to environmental tobacco smoke (ETS), which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies.

METHODS

Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing COPD. Participants were recruited from all 48 contiguous U.S. states by random digit dialing. Lifetime ETS exposure was ascertained by structured telephone interview. We used a standard epidemiologic approach to define COPD based on a self-reported physician diagnosis of chronic bronchitis, emphysema, or COPD.

RESULTS

Higher cumulative lifetime home and work exposure were associated with a greater risk of COPD. The highest quartile of lifetime home ETS exposure was associated with a greater risk of COPD, controlling for age, sex, race, personal smoking history, educational attainment, marital status, and occupational exposure to vapors, gas, dusts, or fumes during the longest held job (OR 1.55; 95% CI 1.09 to 2.21). The highest quartile of lifetime workplace ETS exposure was also related to a greater risk of COPD (OR 1.36; 95% CI 1.002 to 1.84). The population attributable fraction was 11% for the highest quartile of home ETS exposure and 7% for work exposure.

CONCLUSION

ETS exposure may be an important cause of COPD. Consequently, public policies aimed at preventing public smoking may reduce the burden of COPD-related death and disability, both by reducing direct smoking and ETS exposure.

[Passive smoking]

INTRODUCTION

Environmental tobacco smoke is a recognized factor of morbidity and mortality. The first victims are children, sometimes starting from conception, but adults are not spared. In practice, evaluation of exposure to tobacco smoke can be achieved with more or less specific markers of tobacco smoke.

CURRENT KNOWLEDGE

Exposure of the fetus to maternal smoking and of the infant to environmental smoke can have a serious sometimes life-threatening impact. Such exposure increases the risk of spontaneous abortion, ectopic pregnancy, intrauterine growth retardation, premature membrane rupture, preterm birth, retroplacental hematoma, placenta praevia, and sudden infant death. Adult respiratory and cardiovascular disease are also influenced by environmental smoke. In France passive smoking causes premature death of 3000 persons per year.

PERSPECTIVES

Better knowledge of the risks of exposure to passive smoking can facilitate application of legislation with the objective of protecting non-smokers.

CONCLUSIONS

Rigorous application of current legislation is important to achieve the stated goals of prevention of smoking as well as assistance to cease smoking.

Cold weather and GP consultations for respiratory conditions by elderly people in?16 locations in the UK

BACKGROUND

Cold weather is associated with increases in mortality and demands on hospital services in the UK, particularly by the elderly. Less is known about the relationship with patterns of consultation in primary care. We wished to determine the magnitude and consistency of associations between cold temperature and consultations for respiratory conditions in primary care settings at different sites in the UK.

METHODS

Time series analysis of any short-term effects of temperature on daily general practitioner (GP) consultations made by elderly people (65+ years) for lower and upper respiratory tract infections (LRTI, URTI) over a 10-year period, 1992--2001. Practices were situated in 16 urban locations across the UK where a Met Office monitoring station was in operation.

RESULTS

An association between low temperatures and an increase in LRTI consultations was observed in all 16 locations studied. The biggest increase was estimated for the Norwich practices for which a 19.0% increase in LRTI consultations (95% CI 13.6, 24.7) was associated with every 1 degrees C drop in mean temperature below 5 degrees C observed 0-20 days before the day of consultation. Slightly weaker relationships were observed in the case of URTI consultations. A north/south gradient, with larger temperature effects in the north, was in evidence for both LRTI and URTI consultations.

CONCLUSIONS

An effect that was consistent and generally strongest in populations in the north was observed between cold temperature and respiratory consultations. Better understanding of the mechanisms by which cold weather is associated with increases in consultations for respiratory infections could lead to improved strategies for prevention and reduced burdens for health services.

Passive smoking exposure: a risk factor for chronic bronchitis and asthma in adults?

OBJECTIVE

The effects of passive smoke exposure on respiratory health are still under debate. Therefore, we examined the risk of respiratory symptoms related to passive smoke exposure among German adults within the European Community Respiratory Health Survey.

METHODS

The questionnaire data of the population-based sample (n = 1,890) were analyzed. Multiple logistic regression models were carried out for current asthma (asthma symptoms or medication), chronic bronchitis (cough with phlegm for > or = 3 months per year), and wheezing as dependent variables, and self-reported exposure to passive smoke at home and at the workplace as independent variables after adjusting for city, age, gender, active smoking, and socioeconomic status as well as occupational exposure to dusts and/or gases.

RESULTS

The relative odds for chronic bronchitis were significantly higher in subjects reporting involuntary tobacco smoke exposure in the workplace (odds ratio [OR], 1.90; 95% confidence interval [CI], 1.16 to 3.11). Likewise, the adjusted OR for asthma was slightly elevated (OR, 1.51; 95% CI, 0.99 to 2.32). The risk of chronic bronchitis (OR, 3.07; 95% CI, 1.56 to 6.06), asthma (OR, 2.06; 95% CI, 1.07 to 3.97), and wheezing (OR, 2.12; 95% CI, 1.25 to 3.58) increased significantly with a daily exposure of > 8 h.

CONCLUSION

The control of passive smoke exposure in the workplace might reduce the risk of respiratory symptoms independently of exposure to other airborne contaminants.

Differential effects of nicotine and aging on splenocyte proliferation and the production of Th1- versus Th2-type cytokines

Nicotine has a multitude of biological actions in the central and peripheral nervous systems where nicotinic acetylcholine receptors are found. Nicotinic acetylcholine receptors have also been identified on immune cells, but the effects of nicotine on immune responses are not well characterized. These studies tested the hypotheses that nicotine has an effect on both T-lymphocyte proliferation and the production of cytokines by activated T cells, processes that are necessary for effective T-cell-mediated immune responses. In addition, the effects of nicotine on these immune responses in aging animals and the effects of nicotine exposure prior to immunostimulation were investigated. Murine splenocytes were exposed to nicotine and stimulated with concanavalin A (ConA). The highest concentration of nicotine (128 microg/ml) significantly depressed proliferation of T cells both when nicotine and ConA were added concurrently and when nicotine was added 3 hr prior to ConA. Nicotine, added concurrently with ConA at concentrations between 0. 25 and 64 microg/ml, significantly inhibited the production of IL-10 by splenocytes from young adult mice, whereas the inhibition of production of IL-10 by splenocytes from old mice was significantly inhibited, but the response was more variable, depending on the nicotine concentration. In contrast, the production of IFN-gamma by splenocytes from either young adult or old mice was not affected when nicotine (0.016-64 microg/ml) was added concurrently with ConA. Pre-exposure to 1 microg/ml of nicotine for 3 hr significantly enhanced the production of IFN-gamma by splenocytes from young adult mice, whereas pre-exposure to 0.016 microg/ml of nicotine tended to but did not significantly enhance IFN-gamma production. Nicotine is now being used as an over-the-counter drug by people who differ in age and general immunocompetence. Therefore, the effects of nicotine on immune responses, independent from the effects of the other chemicals found in tobacco, need to be investigated.

The prevalence of COPD: using smoking rates to estimate disease frequency in the general population

STUDY OBJECTIVES

To develop and validate a model based on smoking rates that will provide reliable estimates of the true prevalence of COPD that include both clinically detected and undetected patients.

DESIGN

Model based on literature review. Age- and gender-specific rates of lung impairment by smoking status were applied to US smoking data. Resultant estimates were compared to the actual prevalence of obstructive airway disease as estimated by US national surveys. The model then was applied to estimate the prevalence of COPD in several European countries, where national data on undiagnosed lung disease do not exist.

SETTING

The model was adapted from both a literature review and health-care data, and the analysis was applied to the United States and Europe.

RESULTS

Using smoking rates, we estimate from our model that 15.3 million people who are > 40 years of age in the United States have COPD. The prevalence estimate, based on spirometric definitions for COPD in the same age group using the Third National Health and Nutrition Examination Survey (NHANES III), is 17.1 million people. NHANES III and other US national health-care surveys further suggest that only between 2.4 and 7 million people actually have COPD diagnosed; thus, the proportion of COPD that is currently being diagnosed in the United States is between 14% and 46% of all cases. Using smoking rates and our model, which was developed and validated for the United States, we calculated the prevalence of COPD for Germany (2.7 million people), the United Kingdom (3.0 million people), Spain (1.5 million people), Italy (2.6 million people), and France (2.6 million people) in those people > 45 years of age.

CONCLUSIONS

Smoking rates appear to provide a useful method of estimating current COPD prevalence in those countries where more objective data are unavailable. These results are important because recognition of the true burden of disease and corresponding efforts to increase early identification of COPD can help to reduce the morbidity and mortality associated with COPD in populations at risk.

Tobacco-related diseases. Is there a role for antioxidant micronutrient supplementation?

It is clear that smoking causes an increase in free radicals, reactive nitrogen and oxygen species (RNS and ROS, respectively), and that cigarette smoking is associated with increases in the incidence and severity of several diseases including atherosclerosis, cancer, and chronic obstructive lung disease. Although there is still no unequivocal evidence that oxidative stress is a contributor to these diseases or that an increased intake of antioxidant nutrients is beneficial, the observation that smokers have lower circulating levels of some of these nutrients, raises concern. This article discusses the possible links between the observed oxidant-induced damage related to tobacco smoking, effects on cellular mechanisms, and their potential involvement in the causation and enhancement of disease processes.

Involuntary smoking and asthma

Involuntary smoking is the third leading preventable cause of death, and among children it causes lower respiratory infections, middle ear disease, sudden infant death syndrome, and asthma. Half the world's children may be exposed to environmental tobacco smoke (ETS), exacerbating symptoms in 20% of children with asthma. Recent studies have reinforced previous conclusions that ETS exposure causes onset of childhood asthma and exacerbation of symptoms throughout life. The exact mechanisms by which this is accomplished are still unclear, as are the relative contributions of prenatal versus postnatal exposure. However, favorable health outcomes can be attained with reduced exposure. Among the few studies of ETS exposure reduction interventions, low-intensity advice methods appeared ineffective, and counseling parent smokers appeared successful. Direct counseling of school-aged children to avoid ETS has yet to be tested. Community norms may need to shift further in favor of protecting children and others from ETS before minimal interventions can be successful. This will require combined and ongoing efforts of the medical and public health establishments, in concert with legislation mandating tobacco-free public places and with ETS-related media campaigns.