Environmental tobacco smoke and adult asthma. The impact of changing exposure status on health outcomes

Association of M470V polymorphism of CFTR gene with variability of clinical expression of asthma: Case-report study

INTRODUCTION AND OBJECTIVES

Asthma is a complex genetic disorder. Several genes have been found associated with asthma. The cystic fibrosis transmembrane conductance regulator (CFTR) gene is one of them. The aim of this study was to perform a comparative analysis of the genotype and allele frequency distributions of the biallelic marker M470V within the CFTR gene on mutant and wide chromosomes.

PATIENTS AND METHODS

The molecular approach consists in the genotyping of the M470V marker by the PCR-RFLP technique in 105 asthmatic patients, aged between four months and 17 years, and 105 healthy subjects.

RESULTS

We found a significant difference in the genotype frequencies between the two studied groups (χ²=9.855, P=0.007). The V/V genotype was over represented in the asthmatic group as compared to the controls (32.38% vs. 16.19%). Whereas, the M/V genotype is more frequent in healthy subjects (40.95% vs. 28.71%). We also noted a significant difference in allelic distribution of M470V with associated diseases (χ²=9.610, P=0.022).

CONCLUSIONS

The present study is the first report on the distribution of the M470V polymorphism in asthmatic Tunisian patients. We noticed that the M470V variant could modulate the clinical phenotype of asthmatic patients. This preliminary study will establish the molecular basis of this disease in Tunisia.

Prevalence and determinants of asthma among aboriginal adolescents in Canada

Objective: The objective of the study was to determine the prevalence and associated risk factors of asthma in Aboriginal adolescents in Canada based on the Canadian Aboriginal Peoples Survey (APS) 2012. Few studies have investigated the prevalence and risk factors of asthma in Aboriginal adolescents in Canada. Methods: Data from the cross-sectional APS 2012 were analyzed to accomplish the objective. Logistic regression analysis was utilized to determine significant risk factors of lifetime diagnosis of asthma among Aboriginal adolescents. The outcome of interest for adolescents was based on the question: "Do you have asthma that have been diagnosed by a health professional?" Individual, environmental, and contextual factors were tested for an association with lifetime diagnosis of asthma among adolescents. Results: The overall prevalence of lifetime diagnosis of asthma was 16.0%. The prevalence of lifetime diagnosis of asthma was 16.8% for adolescent boys and 15.3% for adolescent girls. Based on multivariable logistic regression analysis, the risk factors of lifetime diagnosis of asthma were: age, income, being overweight, smoking inside the home, having one to two children under 18 years in the household, history of bronchitis, living in an urban residence, education, and geographical location. Female sex was reported to have a protective effect on or reduce risk of the prevalence of lifetime diagnosis of asthma compared to the male sex. Conclusions: Lifetime diagnosis of asthma prevalence appears to be lower in Aboriginal adolescent girls than in adolescent boys. Lifetime diagnosis of asthma prevalence in these adolescents is associated with age, income, education, being overweight, smoking inside the home, history of bronchitis, and location of residence, both geographical region and urban residence. The prevalence of lifetime diagnosis of asthma among Aboriginal adolescent is higher compared to the general adolescent population in Canada.

Modelling the asthma phenotype: impact of cigarette smoke exposure

Background

Asthmatics that are exposed to inhaled pollutants such as cigarette smoke (CS) have increased symptom severity. Approximately 25% of adult asthmatics are thought to be active smokers and many sufferers, especially in the third world, are exposed to high levels of inhaled pollutants. The mechanism by which CS or other airborne pollutants alter the disease phenotype and the effectiveness of treatment in asthma is not known. The aim of this study was to determine the impact of CS exposure on the phenotype and treatment sensitivity of rodent models of allergic asthma.

Methods

Models of allergic asthma were configured that mimicked aspects of the asthma phenotype and the effect of CS exposure investigated. In some experiments, treatment with gold standard asthma therapies was investigated and end-points such as airway cellular burden, late asthmatic response (LAR) and airway hyper-Reactivity (AHR) assessed.

Results

CS co-exposure caused an increase in the LAR but interestingly attenuated the AHR. The effectiveness of LABA, LAMA and glucocorticoid treatment on LAR appeared to be retained in the CS-exposed model system. The eosinophilia or lymphocyte burden was not altered by CS co-exposure, nor did CS appear to alter the effectiveness of glucocorticoid treatment. Steroids, however failed to reduce the neutrophilic inflammation in sensitized mice exposed to CS.

Conclusions

These model data have certain parallels with clinical findings in asthmatics, where CS exposure did not impact the anti-inflammatory efficacy of steroids but attenuated AHR and enhanced symptoms such as the bronchospasm associated with the LAR. These model systems may be utilised to investigate how CS and other airborne pollutants impact the asthma phenotype; providing the opportunity to identify novel targets.

Comorbidities of asthma and the unified airway

BACKGROUND

Asthma is a comorbid condition that may be seen by otolaryngic allergists when treating their patients with allergic rhinitis (AR). Often asthma is overlooked when aggressive treatment could prevent the development or progression of early disease.

METHODS

This article is a retrospective review of the current literature on asthma as a comorbidity of the unified airway. The unified airway and asthma are clearly defined. The epidemiology, morbidity, mortality, pathophysiologic mechanisms, and the chronicity of asthma are reviewed.

RESULTS

The otolaryngic allergist will become familiar the unified airway concept and the close relationships between AR, chronic rhinosinusitis, and asthma.

CONCLUSION

Otolaryngologists should be aware of the unified airway in order to most effectively treat their patients with AR. Knowledge of the close relationships between asthma and AR will help prevent progression of disease, identify early asthma, and improve the outcomes and quality of life for our patients.

Inhaled medication usage in post-menopausal women and lifetime tobacco smoke exposure: The Women's Health Initiative Observational Study

OBJECTIVE

While active smoking is a causal agent in respiratory disease, the independent role of secondhand smoke (SHS) merits further investigation. We investigated associations between lifetime active smoking and exposure to secondhand smoke - studied independently - and current use of 1 or more inhaled medications as a surrogate for prevalent pulmonary disease in post-menopausal women.

STUDY DESIGN

Information on lifetime active and passive tobacco exposure and inhaled pulmonary medication usage at enrollment was collected from 88,185 postmenopausal women aged 50-79 enrolled in the Women's Health Initiative Observational Study from 1993 to 1998 at 40 centers in the United States. Participants were recruited from localities surrounding the study centers using a variety of methods, including informational mailings and mass media campaigns.

MAIN OUTCOME MEASURES

Multivariate adjusted regression models were used to estimate odds ratios and 95% CI according to levels of active smoking and SHS exposure, and trends were tested across categories.

RESULTS

Ever active smokers had an overall OR of 1.97 (95% CI 1.58-2.45) for having one or more prescribed inhaled medication compared with never-smoking women not exposed to active or passive smoke. The overall OR for using inhalers for never-smoking women exposed to any SHS compared with the same reference group was 1.33 (95% CI 1.07-1.65). In a quantified analysis of SHS, never-smoking women with the highest levels of lifetime SHS exposure had an estimated risk of inhaled medication usage of 1.74 (95% CI 1.32-2.30).

CONCLUSIONS

The risk of requiring one or more prescribed inhaled medications for pulmonary disease was significantly higher in post-menopausal women who ever smoked or who had lifetime exposure to SHS.

Why otolaryngologists and asthma are a good match: the allergic rhinitis-asthma connection

Consideration of the unified airway model when managing patients with rhinitis and or asthma allows a more comprehensive care plan and therefore improved patient outcomes. Asthma is linked to rhinitis both epidemiologically and biologically, and this association is even stronger in individuals with atopy. Rhinitis is not only associated with but is a risk factor for the development of asthma. Management of rhinitis improves asthma control. Early and aggressive treatment of allergic rhinitis may prevent the development of asthma. In patients with allergic rhinitis that is not sufficiently controlled by allergy medication, allergen-directed immunotherapy should be considered.

Pilot study results from a brief intervention to create smoke-free homes

Very few community-based intervention studies have examined how to effectively increase the adoption of smoke-free homes. A pilot study was conducted to test the feasibility, acceptability, and short-term outcomes of a brief, four-component intervention for promoting smoke-free home policies among low-income households. We recruited forty participants (20 smokers and 20 nonsmokers) to receive the intervention at two-week intervals. The design was a pretest-posttest with follow-up at two weeks after intervention. The primary outcome measure was self-reported presence of a total home smoking ban. At follow-up, 78% of participants reported having tried to establish a smoke-free rule in their home, with significantly more nonsmokers attempting a smoke-free home than smokers (P = .03). These attempts led to increased smoking restrictions, that is, going from no ban to a partial or total ban, or from a partial to a total ban, in 43% of the homes. At follow-up, 33% of the participants reported having made their home totally smoke-free. Additionally, smokers reported smoking fewer cigarettes per day. Results suggest that the intervention is promising and warrants a rigorous efficacy trial.

Risk factors for COPD spirometrically defined from the lower limit of normal in the BOLD project

Chronic obstructive pulmonary disease (COPD) is predicted to become the third most common cause of death and disability worldwide by 2020. The prevalence of COPD defined by the lower limit of normal was estimated using high-quality spirometry in surveys of 14 populations aged ≥ 40 yrs. The strength and consistency of associations were assessed using random effects meta-analysis. Pack-years of smoking were associated with risk of COPD at each site. After adjusting for this effect, we still observed significant associations of COPD risk with age (OR 1.52 for a 10 yr age difference, 95% CI 1.35-1.71), body mass index in obese compared with normal weight (OR 0.50, 95% CI 0.37-0.67), level of education completed (OR 0.76, 95% CI 0.67-0.87), hospitalisation with a respiratory problem before age 10 yrs (OR 2.35, 95% CI 1.42-3.91), passive cigarette smoke exposure (OR 1.24, 95% CI 1.05-1.47), tuberculosis (OR 1.78, 95%CI 1.17-2.72) and a family history of COPD (OR 1.50, 95% CI 1.19-1.90). Although smoking is the most important risk factor for COPD, other risk factors are also important. More research is required to elucidate relevant risk factors in low- and middle-income countries where the greatest impact of COPD will occur.

Detrimental effects of environmental tobacco smoke in relation to asthma severity

BACKGROUND

Environmental tobacco smoke (ETS) has adverse effects on the health of asthmatics, however the harmful consequences of ETS in relation to asthma severity are unknown.

METHODS

In a multicenter study of severe asthma, we assessed the impact of ETS exposure on morbidity, health care utilization and lung functions; and activity of systemic superoxide dismutase (SOD), a potential oxidative target of ETS that is negatively associated with asthma severity.

FINDINGS

From 2002-2006, 654 asthmatics (non-severe 366, severe 288) were enrolled, among whom 109 non-severe and 67 severe asthmatics were routinely exposed to ETS as ascertained by history and validated by urine cotinine levels. ETS-exposure was associated with lower quality of life scores; greater rescue inhaler use; lower lung function; greater bronchodilator responsiveness; and greater risk for emergency room visits, hospitalization and intensive care unit admission. ETS-exposure was associated with lower levels of serum SOD activity, particularly in asthmatic women of African heritage.

INTERPRETATION

ETS-exposure of asthmatic individuals is associated with worse lung function, higher acuity of exacerbations, more health care utilization, and greater bronchial hyperreactivity. The association of diminished systemic SOD activity to ETS exposure provides for the first time a specific oxidant mechanism by which ETS may adversely affect patients with asthma.

A randomized controlled trial of self-management education for asthma patients in the emergency department

STUDY OBJECTIVE

Patients using the emergency department (ED) for asthma may benefit from self-management education. Our goal is to test an educational intervention in 296 asthma ED patients.

METHODS

This was a randomized controlled trial with concealed allocation. Controls received instruction from an asthma knowledge test, peak flowmeter training, and asthma brochures. Intervention patients received these plus a self-management workbook, a behavioral contract, inhaler training, and telephone reinforcements. The main outcome was change in Asthma Quality of Life Questionnaire (AQLQ) score at 8 weeks (a change of 1.5 is a marked clinically important difference). Secondary outcomes were repeated ED visits and change in AQLQ scores at 4, 12, and 16 weeks and 1 year.

RESULTS

Mean age of patients was 44 years, and 93% had the 8-week follow-up. Enrollment AQLQ scores were comparable and increased at 8 weeks by more than a marked clinically important difference in both groups. For controls, the change in score was 1.95 (95% confidence interval [CI] 1.74 to 2.16; P<.001), for intervention patients the change in score was 1.83 (95% CI 1.64 to 2.03; P<.001), and the difference between groups was 0.11 (95% CI -0.17 to 0.40; P=.43). Patients who improved more (ie, change was above the group mean) were more likely to be high school graduates (odds ratio=1.9; 95% CI 1.0 to 3.8), previous or current smokers at enrollment (odds ratio=2.2; 95% CI 1.3 to 3.5), and to have been admitted to the hospital from the ED (odds ratio=1.7; 95% CI 1.0 to 2.8). Similar variables were associated with AQLQ outcomes in hierarchic analyses during 16 weeks. Repeated ED visits occurred for 12% of patients at 8 weeks and in multivariate analysis were associated with no hospitalization for the index ED visit, difficult access to outpatient care, and previous ED visits. Fewer patients (16%) had an ED visit at 12 weeks compared with a similar time before enrollment (36%).

CONCLUSION

Patients in both groups had marked sustained improvements in clinical status 16 weeks after an ED visit for asthma. A self-management education intervention delivered in the ED and reinforced by telephone was successfully implemented, with high retention rates, but did not provide incremental benefit for quality of life and short-term repeated ED visit outcomes.

Racial differences in biologic predictors of severe asthma: Data from the Severe Asthma Research Program

BACKGROUND

Biologic factors are known to contribute to asthma severity. It is unknown whether these factors differentially contribute to asthma severity in black compared with white subjects.

OBJECTIVE

We sought to assess the extent to which racial disparities between black and white subjects with severe asthma are attributable to physiologic, immunoinflammatory, and sociodemographic variables.

METHODS

Black and white asthmatic adults enrolled in a cross-sectional study focused on severe asthma were evaluated. Severe asthma was identified by using the American Thoracic Society definition. After initial univariable analyses, unconditional logistic regression models were used to estimate the probability of having severe asthma for black and white subjects.

RESULTS

Differences in severe asthma in black compared with white subjects were observed. In univariable analysis IgE level was not associated with severe asthma in black or white subjects, whereas in multivariable analysis IgE level was significantly associated with severe asthma for black subjects (P = .014) but not for white subjects. The odds of having severe asthma more than doubled for black subjects with 2 or more family members with asthma (P = .026), whereas the odds of severe asthma for white participants with a strong family history of asthma decreased by almost half (P = .05). Atopy was negatively associated with severe asthma in both races in univariable analysis but remained significant only in black subjects, whereas comorbidities were associated with severe asthma in white subjects.

CONCLUSION

Biologic factors were distinctly associated with severe asthma only in black subjects. Studies that incorporate comprehensive evaluation of biologic factors associated with asthma might lead to the development of therapies that target biologic abnormalities in black subjects.

Toll-like receptor-9 agonist inhibits airway inflammation, remodeling and hyperreactivity in mice exposed to chronic environmental tobacco smoke and allergen

BACKGROUND

As passive environmental tobacco smoke (ETS) exposure in nonsmokers can increase both asthma symptoms and the frequency of asthma exacerbations, we utilized a mouse model, in which ovalbumin (OVA) + ETS induce significantly increased levels of eosinophilic airway inflammation and remodeling compared to either stimulus alone, to determine whether a Toll-like receptor-9 (TLR-9) agonist could reduce levels of airway inflammation, airway remodeling and airway hyperreactivity (AHR).

METHODS

Mice treated with or without a TLR-9 agonist were sensitized to OVA and challenged with OVA + ETS for 1 month. AHR to methacholine was assessed in intubated and ventilated mice. Lung Th2 cytokines and TGF-beta(1) were measured by ELISA. Lungs were processed for histology and immunohistology to quantify eosinophils, mucus, peribronchial fibrosis and smooth muscle changes using image analysis.

RESULTS

Administration of a TLR-9 agonist to mice coexposed to chronic ETS and chronic OVA allergen significantly reduced levels of eosinophilic airway inflammation, mucus production, peribronchial fibrosis, the thickness of the peribronchial smooth muscle layer, and AHR. The reduced airway remodeling in mice treated with the TLR-9 agonist was associated with significantly reduced numbers of peribronchial MBP+ and peribronchial TGF-beta(1)+ cells, and with significantly reduced levels of lung Th2 cytokines [interleukin-5 and interleukin-13] and TGF-beta(1).

CONCLUSION

These studies demonstrate that TLR-9-based therapies inhibit airway inflammation, remodeling and AHR in mice coexposed to ETS and allergen who exhibit enhanced airway inflammation and remodeling.

Environmental tobacco smoke exposure does not prevent corticosteroids reducing inflammation, remodeling, and airway hyperreactivity in mice exposed to allergen

The ability of corticosteroids to reduce airway inflammation and improve lung function is significantly reduced in asthmatics who are tobacco smokers compared with asthmatics who are nonsmokers. As not only high levels of tobacco smoke exposure in active smokers, but also significantly lower levels of tobacco smoke exposure from passive environmental tobacco smoke (ETS) exposure in nonsmokers can increase both asthma symptoms and the frequency of asthma exacerbations, we utilized a mouse model to determine whether corticosteroids can reduce levels of airway inflammation, airway remodeling, and airway hyperreactivity in mice exposed to the combination of chronic ETS and ovalbumin (OVA) allergen. Chronic ETS exposure alone did not induce increases in eosinophilic airway inflammation, airway remodeling, or airway hyperreactivity. Mice exposed to chronic OVA allergen had significantly increased levels of peribronchial fibrosis, increased thickening of the smooth muscle layer, increased mucus, and increased airway hyperreactivity, which was significantly enhanced by coexposure to the combination of chronic ETS and chronic OVA allergen. Administration of corticosteroids to mice exposed to chronic ETS and OVA allergen significantly reduced levels of eosinophilic airway inflammation, mucus production, peribronchial smooth muscle thickness, airway hyperreactivity, and the number of peribronchial TGF-beta1+ cells. Overall, this study demonstrates that corticosteroids can significantly reduce levels of eosinophilic inflammation, mucus expression, airway remodeling, and airway hyperreactivity in chronic ETS-exposed mice challenged with allergen.

Forty years of secondhand smoke research: the gap between discovery and delivery

CONTEXT

Public health initiatives often focus on the discovery of risk factors associated with disease and death. Although this is an important step in protecting public health, recently the field has recognized that it is critical to move along the continuum from discovery of risk factors to delivery of interventions, and to improve the quality and speed of translating scientific discoveries into practice.

EVIDENCE ACQUISITION

To understand how public health problems move from discovery to delivery, citation network analysis was used to examine 1877 articles on secondhand smoke (SHS) published between 1965 and 2005. Data were collected and analyzed in 2006-2007.

EVIDENCE SYNTHESIS

Citation patterns showed discovery and delivery to be distinct areas of SHS research. There was little cross-citation between discovery and delivery research, including only nine citation connections between the main paths. A discovery article was 83.5% less likely to cite a delivery article than to cite another discovery article (OR=0.165 [95% CI=0.139, 0.197]), and a delivery article was 64.3% less likely (OR=0.357 [95% CI=0.330, 0.386]) to cite a discovery article than to cite another delivery article. Research summaries, such as Surgeon General reports, were cited frequently and appear to bridge the discovery-delivery gap.

CONCLUSIONS

There was a lack of cross-citation between discovery and delivery, even though they share the goal of understanding and reducing the impact of SHS. Reliance on research summaries, although they provide an important bridge between discovery and delivery, may slow the development of a field.

Impact of the Spanish smoking law on exposure to secondhand smoke in offices and hospitality venues: before-and-after study

BACKGROUND/OBJECTIVES

A smoking law was passed by the Spanish Parliament in December 2005 and was enforced by 1 January 2006. The law bans smoking in all indoor workplaces but only in some hospitality venues, because owners are allowed to establish a smoking zone (venues>100 m2) or to allow smoking without restrictions (venues<100 m2). The objective of the study is to assess the impact of the Spanish smoking law on exposure to secondhand smoke (SHS) in enclosed workplaces, including hospitality venues.

MATERIALS AND METHODS

The study design is a before-and-after evaluation. We studied workplaces and hospitality venues from eight different regions of Spain. We took repeated samples of vapor-phase nicotine concentration in 398 premises, including private offices (162), public administration offices (90), university premises (43), bars and restaurants (79), and discotheques and pubs (24).

RESULTS

In the follow-up period, SHS levels were markedly reduced in indoor offices. The median decrease in nicotine concentration ranged from 60.0% in public premises to 97.4% in private areas. Nicotine concentrations were also markedly reduced in bars and restaurants that became smoke-free (96.7%) and in the no-smoking zones of venues with separate spaces for smokers (88.9%). We found no significant changes in smoking zones or in premises allowing smoking, including discotheques and pubs.

CONCLUSIONS

Overall, this study shows the positive impact of the law on reducing SHS in indoor workplaces. However, SHS was substantially reduced only in bars and restaurants that became smoke-free. Most hospitality workers continue to be exposed to very high levels of SHS. Therefore, a 100% smoke-free policy for all hospitality venues is required.

[Impact of low socioeconomic status on the demography and co-morbidities of asthma]

OBJECTIVES

Asthma is a frequent and serious chronic respiratory disease which is sometimes fatal. It involves all ages and all social subclasses. The goal of our study was to determine the demography of asthma in a low socio-economic community in Lebanon and to describe its association with various epidemiologic factors.

MATERIALS AND METHODS

The computerized data of 44.814 patients of a nongovernmental organization (Hariri Foundation), in Lebanon were reviewed. Asthmatic patients diagnosed by a health professional on the basis of medical criteria during the period from January 2003 to June 2005 were included in the analysis. The socio-economic characteristics of this population were retrieved and their geographical distributions were depicted. The study focused on the association of asthma with cutaneous and ocular allergies, depression, obesity and alcohol consumption.

RESULTS

The majority of asthmatic patients (75%) belonged to a low socio-economic environment with a salary lower than $200 per month. 31% were illiterate. 583 (1.3%) of patients on the database were asthmatic. The rate in children was higher (2.08%) than in adults (1.09%). The majority of asthma occurred among subjects from Bekaa valley and South Lebanon. Asthma was associated more strongly with being an ex-smoker (OR 4.37; 95% CI 2.38, 8.02) than being a current smoker (OR 1.44; 95% CI 1.11, 1.87). A significant and strong association was found with depression (OR 25.6; 95% CI 3.32, 197.6), obesity (OR 4.09, 95% CI 1.31, 12.73) and with regular alcohol consumption (OR 11.78; 95% CI 1.55, 89.44).

CONCLUSION

This study describes the association of asthma in this population with low socio-economic status. By defining the demographic characteristics of the asthma population the Ministry of Health and the medical organizations concerned should be better able to manage the condition. This study confirms, in a Lebanese population, the epidemiological associations described in other populations around the world.

Passive smoking and adult asthma

Asthma is a common chronic health condition, affecting 5% of the United States adult population. In most developed countries, the prevalence of asthma and its severity continues to increase. Understanding the factors contributing to asthma morbidity and mortality has important clinical and public health implications. This article evaluates the evidence that secondhand smoke exposure is a risk factor for new-onset asthma among adults and exacerbates pre-existing adult asthma, resulting in greater symptom burden and morbidity.

Reduction in asthma-related emergency department visits after implementation of a smoke-free law

BACKGROUND

Secondhand tobacco smoke increases the risk for the development and increasing severity of asthma among adults and children. Reducing exposure to secondhand smoke decreases symptomatic exacerbations among patients with asthma. Emergency department (ED) visits for asthma were assessed before and after the implementation of smoke-free legislation in Lexington-Fayette County, Ky.

OBJECTIVE

To evaluate the effects of a smoke-free law on the rate of ED visits for asthma.

METHODS

The study included ED visits for asthma from 4 hospitals in Lexington-Fayette County, Ky. Age-adjusted rates of asthma ED visits were determined. Poisson regression analysis of ED visits from January 1, 2001, to December 31, 2006 compared the ED visit rates between prelaw and postlaw, adjusting for seasonality, secular trends over time, and differences among demographic subgroups. The actual rates were graphed with the Poisson curve showing the rates predicted by the model. A second prediction curve was generated to show the projected rates in the postlaw period if the law had not been implemented.

RESULTS

Adjusting for seasonality, secular trends, and demographic characteristics, ED visits for asthma declined 22% from prelaw to postlaw (P < .0001; 95% CI, 14% to 29%). The rate of decline was 24% in adults age 20 years and older (P < .0001), whereas the decrease among children 19 years or younger was 18% (P = .01).

CONCLUSION

Although this study did not establish causation, the smoke-free law was associated with fewer asthma ED visits among both children and adults, with a more significant decline among adults.

A qualitative study of how families decide to adopt household smoking restrictions

Household smoking bans reduce exposure to secondhand smoke in adult nonsmokers and children. To explore the process families go through in adopting voluntary household smoking restrictions, qualitative interviews were conducted with rural African American and White adults in 102 households. The study investigated how families decide to restrict smoking in the home, who has significant influence in the decision-making process, the kinds of disagreements families have about household smoking restrictions, and reasons some families never consider household smoking policies. These findings have implications for designing intervention strategies and messages to promote household smoking bans and help family members negotiate smoke-free homes.

Executive summary: asthma and the unified airway

Asthma is a common comorbid disorder that will be seen by otolaryngologists in their treatment of patients with rhinitis, rhinosinusitis, and otitis media. Among otolaryngologists, however, a diagnosis of asthma is infrequently considered in this patient population. Otolaryngologists, however, may be in an important position to recognize this potential diagnosis and provide treatment or appropriate referral. To further develop this relationship among upper and lower airway inflammation, and to provide important information to otolaryngologists regarding this relationship, a multidisciplinary workgroup was impaneled by the American Academy of Otolaryngologic Allergy in August 2006. The full report of this meeting is published separately as a Supplement to Otolaryngology-Head and Neck Surgery. This Executive Summary provides a brief synopsis of that document, with a focus on comorbid respiratory inflammation for otolaryngologists. In the treatment of their patients with allergic rhinitis and rhinosinusitis, otolaryngologists must be aware of the possible presence of asthma so that appropriate treatment and/or referral can be initiated. The impact of this practice will allow more comprehensive treatment of patients with upper and lower airway disease, and will improve patient symptoms, function, and quality of life.

Asthma and the unified airway

Inflammatory processes of the upper and lower airway commonly co-exist. Patients with upper respiratory illnesses such as allergic rhinitis and acute and chronic rhinosinusitis often present to both otolaryngologists and primary care physicians for treatment of their symptoms of nasal and sinus disease. These patients often have concurrent lower respiratory illnesses such as asthma that may be contributing to their overall symptoms and quality of life. Unfortunately, asthma frequently remains undiagnosed in this population. It was the objective of this paper to examine the relationship between upper respiratory illnesses such as rhinitis and rhinosinusitis and lower respiratory illnesses such as asthma, and to provide a framework for primary care and specialty physicians to approach these illnesses as a spectrum of inflammatory disease. The present manuscript was developed by a multidisciplinary workgroup sponsored by the American Academy of Otolaryngic Allergy. Health care providers in various specialties contributed to the manuscript through preparation of written materials and through participation in a panel discussion held in August 2006. Each author was tasked with reviewing a specific content area and preparing a written summary for inclusion in this final document. Respiratory inflammation commonly affects both the upper and lower respiratory tracts, often concurrently. Physicians who are treating patients with symptoms of allergic rhinitis and rhinosinusitis must be vigilant to the presence of asthma among these patients. Appropriate diagnostic methods should be used to identify individuals with concurrent respiratory illnesses, and comprehensive treatment should be instituted to reduce symptoms and improve quality of life.

Impact of home environment characteristics on asthma quality of life and symptom scores

We explore the relationship between home-based triggers, asthma symptoms, and quality of life (QOL) with data from 177 adult and pediatric participants who received a home environmental assessment. Outcomes included the Asthma Quality of life Questionnaire, the Prediatric Asthma Quality of Life Questionnaire, the Paediatric Asthma Caregiver's Quality of Questionnaires and the Lara Asthma Symptom Scale. The absence of roaches and the use of dust mite covers were positively associated with QOL in pediatric and adult participants. Frequent bed sheet washing was associated with increased symptoms and decreased quality of life in adults and caregivers of pediatric participants. These findings confirm existing wisdom on roaches and dust mite covers and raise important questions about bed sheet washing recommendations.

Zileuton: clinical implications of 5-Lipoxygenase inhibition in severe airway disease

The 5-Lipoxygenase pathway results in the formation of leukotrienes, including leukotriene B(4) (LTB(4)), 5-oxo-6E,8Z,11Z,14Z-eicosatetranoic acid and the cysteinyl leukotrienes (LTC(4), LTD(4) and LTE(4)) and activates all four leukotriene receptors, BLT1, BLT2, cysLT(1) and cysLT(2). Zileuton is the only commercially available inhibitor of the 5-Lipoxygenase pathway. In a number of clinical trials, zileuton has been shown to improve airway function and inflammation, asthma symptom control and quality of life in asthmatics. Given the important role that leukotrienes play in airway inflammation, zileuton provides an additional therapeutic option in the management of chronic, persistent asthma, particularly those asthmatics with more severe disease. In addition, zileuton has shown promise in a number of other conditions, including upper airway inflammatory conditions, dermatological disease and chronic obstructive pulmonary disease. The development of new formulations, including a controlled release tablet formulation for b.i.d. dosing and an intravenous preparation for acute asthma exacerbations may enhance clinical utility and expand therapeutic indications.

Asthma control or severity: that is the question

In the first National Heart Lung and Blood Institute and Global Initiative for Asthma (GINA) guidelines, the level of symptoms and airflow limitation and its variability allowed asthma to be subdivided by severity into four subcategories (intermittent, mild persistent, moderate persistent, and severe persistent). It is important to recognize, however, that asthma severity involves both the severity of the underlying disease and its responsiveness to treatment. Thus, the first update of the GINA guidelines defined asthma severity depending on the clinical features already proposed as well as the current treatment of the patient. In addition, severity is not a fixed feature of asthma, but may change over months or years, whereas the classification by severity suggests a static feature. Moreover, using severity as an outcome measure has limited value in predicting what treatment will be required and what the response to that treatment might be. Because of these considerations, the classification of asthma severity is no longer recommended as the basis for treatment decisions, a periodic assessment of asthma control being more relevant and useful.

Smoking affects response to inhaled corticosteroids or leukotriene receptor antagonists in asthma

RATIONALE

One-quarter to one-third of individuals with asthma smoke, which may affect response to therapy and contribute to poor asthma control.

OBJECTIVES

To determine if the response to an inhaled corticosteroid or a leukotriene receptor antagonist is attenuated in individuals with asthma who smoke.

METHODS

In a multicenter, placebo-controlled, double-blind, double-dummy, crossover trial, 44 nonsmokers and 39 light smokers with mild asthma were assigned randomly to treatment twice daily with inhaled beclomethasone and once daily with oral montelukast.

MEASUREMENTS AND MAIN RESULTS

Primary outcome was change in prebronchodilator FEV(1) in smokers versus nonsmokers. Secondary outcomes included peak flow, PC(20) methacholine, symptoms, quality of life, and markers of airway inflammation. Despite similar FEV(1), bronchodilator response, and sensitivity to methacholine at baseline, subjects with asthma who smoked had significantly more symptoms, worse quality of life, and lower daily peak flow than nonsmokers. Adherence to therapy did not differ significantly between smokers and nonsmokers, or between treatment arms. Beclomethasone significantly reduced sputum eosinophils and eosinophil cationic protein (ECP) in both smokers and nonsmokers, but increased FEV(1) (170 ml, p = 0.0003) only in nonsmokers. Montelukast significantly increased a.m. peak flow in smokers (12.6 L/min, p = 0.002), but not in nonsmokers.

CONCLUSIONS

In subjects with mild asthma who smoke, the response to inhaled corticosteroids is attenuated, suggesting that adjustments to standard therapy may be required to attain asthma control. The greater improvement seen in some outcomes in smokers treated with montelukast suggests that leukotrienes may be important in this setting. Larger prospective studies are required to determine whether leukotriene modifiers can be recommended for managing asthma in patients who smoke.

Epidemiology of asthma

The epidemiology of asthma is complex but essential in enhancing the understanding of a disease that affects millions of patients. Asthma is associated with significant morbidity and mortality. Asthma prevalence rates in the United States reached a plateau after 1998 with an estimated overall prevalence of 3.8% in 2003. Racial disparities exist and there are staggering differences in morbidity and mortality. The analysis of data collected from epidemiologic studies continues to be a critical part of enhancing the understanding of the pathophysiology of asthma, which will lead to improved patient outcomes.

Correlates of Attitudes Toward a Smoking Ban in Vehicles

To examine the predictors of attitudes toward a smoking ban in vehicles, a computer-assisted telephone interview was conducted for a representative sample of Indiana adult residents using the random-digit-dialing method. Less than one third of the total respondents favored a smoking ban for car drivers and passengers, whereas about two thirds favored the smoking ban in public places. Fifty-four percent and 63 percent of nonsmokers opposed the smoking ban for car drivers and passengers, respectively. Religiosity was a significant predictor for attitudes toward a smoking ban for both drivers and passengers when controlling for other predictors, including smoking status, employment status, and age group. Gender, income group, and race/ethnicity were insignificant.

The effects of outdoor air pollution and tobacco smoke on asthma

Outdoor air pollution and environmental tobacco smoke adversely affect health in persons with asthma. Increased levels of ozone, particulate matter, and environmental tobacco smoke have been associated with increased asthma symptoms and health care use and with reduced lung function. These air contaminants have proinflammatory actions that can magnify existing lower airway inflammation in patients with asthma. Exposure to air contaminants can increase the risk of developing asthma in susceptible persons. Outdoor air pollution and environmental tobacco smoke may affect allergen-induced inflammation by initiating TH(2) responses to antigens or by exacerbating such inflammation in persons already sensitized.

Airway disease risk from environmental tobacco smoke among coffeehouse workers in Turkey

OBJECTIVES

To examine the effect of ETS exposure on respiratory symptoms and pulmonary function and to compare workers in coffeehouses to those in other occupations in order to assess the risk of respiratory illness in this occupation.

DESIGN

Cross sectional study.

SETTING

The study area consisted of the three metropolitan districts of the city of Izmir, Turkey. 86 coffeehouses and 80 other small scale shops which had no known respiratory risk factor, located in the same area, were taken as the study group.

SUBJECTS

207 workers were assessed.

MAIN OUTCOME MEASUREMENTS

Subjects answered a questionnaire about demographic and working characteristics, respiratory symptoms, and smoking behaviour. Physical examinations and spirometric measurements were carried out at the workplaces.

RESULTS

There was a significant increase in respiratory symptoms in coffeehouse workers. Working in a coffeehouse showed a significant risk for chronic bronchitis (odds ratio (OR) 4.3). In coffeehouse workers, forced expiratory volume in one second (FEV(1)) decreased 5.1%, forced vital capacity (FVC) 3.4%, FEV(1)/FVC 1.6%, peak expiratory flow (PEF) 6.45%, and forced expiratory flow (FEF(25)) 7.2%, FEF(50) 10%, and FEF(25-75) 9.8%. Among workers who were described as having an "airway disease", coffeehouse workers were significantly greater in number. When age, body mass index, and smoking behaviour were controlled, working in a coffeehouse was strongly associated with "airway disease" compared to other workers (OR 5.35, 95% confidence interval 2.41 to 11.87).

CONCLUSIONS

Workers in coffeehouses showed significant increases in respiratory symptoms and decreased pulmonary function. All workers need to gain an awareness of these occupational risks and working conditions should be improved immediately.

Respiratory health consequences of environmental tobacco smoke

Over the last several decades there has been a growing interest in examining the health consequences of environmental tobacco smoke (ETS). As a result of a wide body of research, ETS is now considered an unacceptable and entirely preventable public health hazard, and public policy increasingly discourages the presence of tobacco smoke in the public domain. This article provides an overview of the composition of ETS and the major diseases and disorders strongly linked to ETS, emphasizing the effects of ETS on pulmonary function, asthma, and lung cancer.

Effect of obesity on asthma among adult Indian women

OBJECTIVE

Both obesity and asthma are on the rise worldwide. This study examined the association between obesity and asthma prevalence in adult women in India.

METHODS

The analysis used information on 82 464 nonpregnant, ever-married women aged 15-49 y, included in India's 1998-99 National Family Health Survey. The effects of measured Body Mass Index (BMI) on reported asthma were estimated using logistic regression, after adjusting for tobacco smoking (active and passive), cooking smoke, age, education, work status, media habits, food habits, house type, separate kitchen, indoor crowding, religion, caste/tribe, household living standard, urban/rural residence, and geographic region.

RESULTS

Obese women (BMI>/=30.0 kg/m(2)) were about twice as likely as those with a normal BMI (18.5-25.0 kg/m(2)) to report suffering from asthma (OR=1.92; 95% CI: 1.40-2.65). The association between obesity and asthma remained strong and statistically significant even when the effects of other selected risk factors and potential confounders were controlled (OR=1.85; 95% CI: 1.30-2.63). Overweight women (25.0</=BMI<30.0 kg/m(2)) also reported significantly higher adjusted asthma prevalence than those with a normal BMI (OR=1.32; 95% CI: 1.07-1.63). Results hold in separate analysis for younger (15-29 y) and older (30-49 y) women.

CONCLUSION

The study finds a strong positive association between obesity and asthma among adult Indian women. To validate this relationship and to establish causality, prospective epidemiological studies, with better measures of overweight conditions and clinical measures of asthma, are needed in developing-country settings.

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.

Discharge of the asthmatic patient

Asthma continues to be a challenging disease to treat in both the inpatient and outpatient settings. The growing database on therapeutic interventions at the time of transition from the acute to chronic phase of this disease is encouraging. Glucocorticoids and inhaled beta-agonists clearly reduce readmission and relapse. Other medications and educational interventions also appear effective. Still, no true discharge guidelines have been established. Multiple statements by consensus panels have recommended using FEV1 or PEFR as indicators of readiness for discharge, but this has not been prospectively validated from either the emergency department or inpatient setting. In contrast, some studies argue that pulmonary functions do not accurately predict relapse and readmission, so the usefulness of these discharge recommendations is debatable. Large studies, especially in the adult asthmatic population, are needed to validate these recommendation.

NAC Manchester Asthma and Allergy Study (NACMAAS): risk factors for asthma and allergic disorders in adults

Asthma and atopic disorders are the most common chronic diseases in the developed countries. Knowledge of the risk factors for these disorders may facilitate the development of preventive strategies aimed at reducing prevalence rates. To investigate the risk factors for asthma and allergic diseases in a large number of adults who are the parents of children in the National Asthma Campaign Manchester Asthma and Allergy Study. All pregnant women and their partners attending "Booking" antenatal clinics were invited to take part in the study. Questionnaire data were collected including the history of asthma and other atopic diseases, pet ownership and smoking habits, and skin prick tests were performed. The prevalence of atopy and the risk factors for asthma and allergic disorders were investigated in all subjects who completed the questionnaire and underwent skin testing. Statistical analysis was carried out using logistic regression. Initially, risk factors were assessed by univariate analysis to see how each potential explanatory variable affected the probability of having allergic disease. Variables were then tested in a forward stepwise multivariate analysis. In 5687 adult subjects there was a very high (48.2%) prevalence of atopy, and 9.7% of subjects had a diagnosis of asthma. In a multivariate regression analysis sensitization to dust mite, cat, dog and mixed grasses were all independently associated with asthma. The odds ratios for current asthma increased with the increasing number of positive skin tests (any two allergens - OR 4.3, 95% CI 3.3-5.5; any three allergens - OR 7.0 95% CI 5.3-9.3; all four allergens - OR 10.4, 95% CI 7.7-14; P < 0.00001). Dog ownership (OR 1.31, 95% CI 1.10-1.57; P = 0.003) and current smoking (OR 1.36, 95% CI 1.15-1.62; P = 0.0004) were significantly and directly associated with "asthma ever". Thirteen per cent of participants reported a history of eczema. In the multivariate analysis the strongest independent associate of eczema was sensitization to dog (OR 1.37, 95% CI 1.14-1.63, P < 0.0001). Apart from dog, the strength of the association between sensitization to common allergens and eczema appeared to be much lower than in the case of asthma. The prevalence of hay fever was high (20.6%), and in the multivariate analysis the association between sensitization to pollen and hay fever was extremely strong (OR 13.6, 95% CI 11.3-16.3; P < 0.0001). The results of the current study emphasize the importance of sensitization to indoor allergens in asthma. However, evidence of a possible direct role of allergen exposure in asthma causation remains unclear.

The relationship between home smoking bans and exposure to state tobacco control efforts and smoking behaviors

PURPOSE

To examine the relationship between home smoking bans and adult smokers' exposure to the statewide California Tobacco Control Program (TCP) and their cigarette smoking behavior.

DESIGN

Cross-sectional survey that was part of the statewide Independent Evaluation of the California Tobacco Control, Prevention and Education Program.

SETTING

Random telephone interviews within 18 California counties.

SUBJECTS

A representative sample of 1315 adult smokers, aged 25 years and older.

MEASURES

The telephone survey included questions about smoking behavior, quitting smoking, exposure to tobacco control program components, home smoking rules, and attitudes related to tobacco use and environmental tobacco smoke (ETS).

RESULTS

Smokers with a home smoking ban were twice as likely (OR = 2.29; 95% CI 1.22, 4.29) to have heard of TCP community programs and three times more likely (OR = 3.18; 95% CI 1.34, 7.57) to have seen and talked about the ETS media spot than smokers with no home smoking policy. Multivariate regression models indicated that having a home smoking ban was related to smoking fewer cigarettes per day and greater interest in quitting smoking compared with smokers with no smoking rules in the home (p < .05).

CONCLUSIONS

These findings suggest that smokers reporting exposure to the California TCP were more likely to have restrictive home smoking policies and that more restrictive home smoking policies were associated with reduced smoking behavior.

Patient-assessed measures of health outcome in asthma: a comparison of four approaches

The study compares the psychometric properties of four different approaches to patient-assessed health outcomes in asthma, including the Asthma Quality of Life Questionnaire (AQLQ), Newcastle Asthma Symptoms Questionnaire (NASQ), SF-12 and EuroQol. The instruments were administered by means of a self-completed postal questionnaire to 394 patients recruited from general practices in the North East of England. Patients completed a follow-up questionnaire at 6 months. The levels of missing data were assessed and instrument scores compared using correlational analysis. Scores were related to self-reports of smoking behaviour, socioeconomic status and health transition. Responsiveness was assessed using standardized response means. Two hundred and thirty-five patients took part in the study giving a response rate of 59.6%. There was a relatively large amount of missing data for the individualized section of the AQLQ. Correlational analysis provided evidence of convergent validity between the specific instruments; the largest correlation was found between NASQ scores and the asthma symptoms scale of the AQLQ (r = 0.84). The NASQ was found to be the most powerful at discriminating between smokers and non-smokers. All four instruments were linearly related to self-reported asthma transition (P<0.05); the specific instruments having the strongest association. The specific instruments showed good levels of responsiveness with the NASQ producing a large SRM of 0.82. SRMs for the AQLQ were of a moderate to large size (0.32-0.77) and the SRMs for the SF-12 and EuroQol were of a small size. The two specific instruments are capable of greater levels of discrimination between groups of patients and are more responsive to changes in health than the generic SF-12 and EuroQol. The greater responsiveness of the NASQ is probably due to its focus being restricted to symptoms of asthma compared to the broader focus of the AQLQ domains. The NASQ has a strong relationship with the AQLQ and is a more practical instrument that is more acceptable to patients. However, the AQLQ does measure broader patient concerns. The SF-12 and EuroQol have greater potential to capture side-effects and have wider scope for application in economic evaluation.

Differential diagnosis of chronic airflow obstruction

Chronic obstructive pulmonary disease is a syndrome including illnesses such as asthma, chronic bronchitis, and emphysema. Although these diseases share a common obstructive component, their optimal treatment and prognosis differ. This article examines the salient features of the history, physical exam, pulmonary function tests, and radiological evaluation which may allow the clinician to differentiate the various diseases that make up COPD; thus allowing the clinician to better target the multiple therapeutic modalities available.

Relationships of active and passive smoking to total IgE in adults of the Epidemiological Study of the Genetics and Environment of Asthma, Bronchial Hyperresponsiveness, and Atopy (EGEA)

The increase of total IgE in relation to active smoking has been shown in the general population, but little is known about subjects with a personal or family history of asthma. The objective of this report is to analyze the relationships of active and passive smoking to total IgE in the Epidemiological Study of the Genetics and Environment of Asthma, Bronchial Hyperresponsiveness, and Atopy (EGEA). The sample studied includes 122 asthmatic probands, 430 first-degree relatives, and 190 control subjects, age 25 to 54 yr. As expected, first-degree relatives had total IgE intermediate between cases and control subjects and men had higher values than women. Current smokers had significantly higher IgE than never smokers. The relationship was statistically significant restricting the analysis in asthmatic probands. In a model taking into account gender, personal and familial history of asthma, socio- occupational class, and the nonindependence of subjects from the same family, IgE were in current smokers, ex-smokers, and never smokers 128, 61, and 76 IU/ml and 77, 41, and 55 IU/ml in men (p = 0.01) and women (p = 0. 05), respectively. The relation was independent of skin test response. Some increase in IgE was observed in both men and women first-degree relatives in relation to passive smoking. That relation was statistically significant in women only (adjusted for asthma values: 103 IU/ml versus 48 IU/ ml, p = 0.02). Results show that an increase in total IgE in relation to active smoking may be evidenced even in asthmatics despite the healthy smoker effect. Susceptible subjects, such as women who are first-degree relatives of asthmatics, may increase total IgE in relation to passive smoking.

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.

Smoking bans in the home and car: Do those who really need them have them?

BACKGROUND

This paper addresses the question of whether individuals who are most in need of household and car smoking bans, such as individuals with children living at home or who have many friends who smoke, are the ones who have them.

METHOD

A representative sample of 6985 California adults ages 18 and older participated in telephone interviews.

RESULTS

Overall, 76% of adults report having home smoking bans and 66% have car smoking bans. Being a smoker or African American, not having children in the home, having more friends who smoke, and lower household income were associated with lower prevalence of both home and car smoking bans (P < 0.01). In multivariate analyses, nonsmokers were 7.9 (95% CI = 3.56, 17.31) times more likely to have a home smoking ban when none of their friends were smokers compared to when most of their friends were smokers. Among smokers, there was an interaction between having children at home and the proportion of friends who smoke. Only 27 to 55% of smokers had home smoking bans unless most of their friends were smokers, then the odds of having a ban were 6.1 (95% CI = 2.76, 13.68) times higher for smokers with children (67% with home bans) than for smokers without children at home (25% with home bans).

CONCLUSIONS

Efforts to increase home and car smoking bans for nonsmokers who have friends who smoke and smokers with children living at home are needed.

Asthma-related work disability in Sweden. The impact of workplace exposures

Work disability due to respiratory disease, especially asthma, is common and costly among working age adults. The goal of this analysis was to characterize the risk factors for such disability. We analyzed data from the Swedish part of the European Community Respiratory Health Survey (ECRHS), a random population-based sample of adults age 20 to 44, enriched with symptomatic subjects at increased likelihood of having asthma. We analyzed structured interview data available for 2,065 subjects and further analyzed methacholine challenge and skin prick test data for 1,562 of these. We defined respiratory work disability as reported job change or work loss due to breathing affected by a job. We used binary generalized linear modeling with a log link to estimate disability risk. Eighty-four subjects (4%) reported such work disability. This increased to 13% among those with asthma (45 of 350 subjects). Adjusting for covariates, occupations at high risk for asthma were associated with disability (prevalence ratio [PR] 1.8; 95% confidence interval [CI] 1.1 to 3.0), as was self-reported regular exposure to environmental tobacco smoke (ETS) at work (PR 1.8; 95% CI 1.1 to 3.1) and self- reported job exposure to vapors, gases, dust, or fumes (VGDF) (PR 4.3; 95% CI 2.2 to 8.6). Workplace ETS exposure was also associated with methacholine challenge-positive asthma reported to be symptomatic at work among male subjects (PR 4. 2; 95% CI 1.8 to 9.8), whereas high asthma-risk occupations were associated with this outcome among female subjects (PR 2.7; 95% CI 1. 05 to 7.1). Respiratory work disability, defined as breathing-related job change due to work loss, was associated with workplace exposures themselves, even after taking into account other covariates. Better control of workplace exposures, including workplace ETS, may reduce work disability caused by respiratory conditions, especially adult asthma.

The adverse health effects of tobacco and tobacco-related products

Tobacco use continues to occur in epidemic proportions and with it, significant morbidity and mortality. One third of smokers will die prematurely of a smoking-related disease. This article reviews the adverse health effects of tobacco use so that clinicians can be aware of the benefits patients will reap when they stop using this lethal substance.