The impact of cigarette smoking on asthma: a population-based international cohort study

Asthma and smoking-induced airway disease without spirometric COPD

Due to the high prevalence rates of cigarette smoking and asthma, current and ex-smokers frequently develop chronic airway disease without spirometric evidence of chronic obstructive pulmonary disease (COPD), either alone or associated with asthma. This review considers the classification, clinical outcomes, inflammatory and imaging variables, phenotypes, and management of current and ex-smokers with airway disease without COPD, focusing on overlaps in those with and without asthma. These individuals have more respiratory symptoms, worse quality of life, increased exacerbation rates, reduced lung function and more comorbidities than never-smokers with asthma or healthy never-smokers. As well as clinical features, airway inflammatory and structural changes in smoking-induced airway disease without COPD overlap with those found in smokers with asthma. Cigarette smoking is associated with worse clinical outcomes in some phenotypes of asthma. Management involves public health measures to control exposure to tobacco smoke, personal advice on smoking cessation and the use of appropriate targeted therapies, although evidence is limited on their effectiveness. Understanding the mechanisms, natural history and management of current and ex-smokers with asthma and smoking-induced airway disease without COPD is a priority for future research.

Allergy in severe asthma

It is well recognized that atopic sensitization is an important risk factor for asthma, both in adults and in children. However, the role of allergy in severe asthma is still under debate. The term 'Severe Asthma' encompasses a highly heterogeneous group of patients who require treatment on steps 4-5 of GINA guidelines to prevent their asthma from becoming 'uncontrolled', or whose disease remains 'uncontrolled' despite this therapy. Epidemiological studies on emergency room visits and hospital admissions for asthma suggest the important role of allergy in asthma exacerbations. In addition, allergic asthma in childhood is often associated with severe asthma in adulthood. A strong association exists between asthma exacerbations and respiratory viral infections, and interaction between viruses and allergy further increases the risk of asthma exacerbations. Furthermore, fungal allergy has been shown to play an important role in severe asthma. Other contributing factors include smoking, pollution and work-related exposures. The 'Allergy and Asthma Severity' EAACI Task Force examined the current evidence and produced this position document on the role of allergy in severe asthma.

The effect of smoking on lung function: a clinical study of adult-onset asthma

The aim of this study was to evaluate the effect of smoking on lung function decline in adult-onset asthma in a clinical, 12-year follow-up study.In the Seinäjoki Adult Asthma Study, 203 patients were followed for 12 years (1999-2013) after diagnosis of new-onset adult asthma. Patients were divided into two groups based on smoking history: <10 or ≥10 pack-years. Spirometry evaluation points were: 1) baseline, 2) the maximum lung function during the first 2.5 years after diagnosis (Max_0-2.5) and 3) after 12 years of follow-up.Between Max_0-2.5 and follow-up, the median annual decline in absolute forced expiratory volume in 1 s (FEV₁) was 36 mL in the group of patients with <10 pack-years of smoking and 54 mL in those with smoking history ≥10 pack-years (p=0.003). The annual declines in FEV₁ % pred (p=0.006), forced vital capacity (FVC) (p=0.035) and FEV₁/FVC (p=0.045) were also accelerated in the group of patients with ≥10 pack-years smoked. In multivariate regression analysis, smoking history ≥10 pack-years became a significant predictor of accelerated decline in FEV₁Among patients with clinically defined adult-onset asthma, smoking history ≥10 pack-years is associated with accelerated loss of lung function.

Fitness, obesity and risk of asthma among Army trainees

BACKGROUND

Epidemiological data suggest an association between overweight/obesity and asthma. However, less is known about the relationship between physical fitness and asthma.

AIMS

To enumerate new-onset asthma diagnoses in Army recruits during the first 2 years of service and determine associations with fitness and excess body fat (EBF) at military entrance.

METHODS

New asthma diagnoses over 2 years in Army recruits at six entrance stations were obtained from military health and personnel records. Poisson regression models were used to determine associations of asthma diagnosis with pre-accession fitness testing, EBF and other potential factors.

RESULTS

In 9979 weight-qualified and 1117 EBF entrants with no prior history of asthma, 256 new cases of asthma were diagnosed within 2 years of military entry. Low level of fitness, defined by a step test and EBF, was significantly associated with new asthma diagnosis [adjusted incidence rate ratio (IRR), 1.47; 95% confidence interval (CI) 1.11-1.96 and adjusted IRR, 1.53; 95% CI 1.06-2.20, respectively].

CONCLUSIONS

Individuals with low fitness levels, EBF or both are at higher risk of asthma diagnosis in the first 2 years of military service.

Patient stratification and the unmet need in asthma

Asthma is often described as an inflammatory disease of the lungs and in most patients symptomatic treatment with bronchodilators or inhaled corticosteroids is sufficient to control disease. Unfortunately there are a proportion of patients who fail to achieve control despite treatment with the best current treatment. These severe asthma patients have been considered a homogeneous group of patients that represent the unmet therapeutic need in asthma. Many novel therapies have been tested in unselected asthma patients and the effects have often been disappointing, particularly for the highly specific monoclonal antibody-based drugs such as anti-IL-13 and anti-IL-5. More recently, it has become clear that asthma is a syndrome with many different disease drivers. Clinical trials of anti-IL-13 and anti-IL-5 have focused on biomarker-defined patient groups and these trials have driven the clinical progression of these drugs. Work on asthma phenotyping indicates that there is a group of asthma patients where T helper cell type 2 (Th2) cytokines and inflammation predominate and these type 2 high (T2-high) patients can be defined by biomarkers and response to therapies targeting this type of immunity, including anti-IL-5 and anti-IL-13. However, there is still a subset of T2-low patients that do not respond to these new therapies. This T2-low group will represent the new unmet medical need now that the T2-high-targeting therapies have made it to the market. This review will examine the current thinking on patient stratification in asthma and the identification of the T2-high subset. It will also look at the T2-low patients and examine what may be the drivers of disease in these patients.

Smoking cessation strategies for patients with asthma: improving patient outcomes

Smoking is common in adults with asthma, yet a paucity of literature exists on smoking cessation strategies specifically targeting this subgroup. Adverse respiratory effects from personal smoking include worse asthma control and a predisposition to lower lung function and chronic obstructive pulmonary disease. Some data suggest that individuals with asthma are more likely than their non-asthmatic peers to smoke regularly at an earlier age. While quit attempts can be more frequent in smokers with asthma, they are also of shorter duration than in non-asthmatics. Considering these asthma-specific characteristics is important in order to individualize smoking cessation strategies. In particular, asthma-specific information such as "lung age" should be provided and longer-term follow-up is advised. Promising emerging strategies include reminders by cellular phone and web-based interventions using consumer health informatics. For adolescents, training older peers to deliver asthma education is another promising strategy. For smokers who are hospitalized for asthma, inpatient nicotine replacement therapy and counseling are a priority. Overall, improving smoking cessation rates in smokers with asthma may rely on a more personalized approach, with the potential for substantial health benefits to individuals and the population at large.

The management of asthmatic smokers

Asthma is still a major public health problem in most countries; new strategies to better control this disease are necessary. Such strategies must include predisposing factors. One of these factors is smoking and a significant fraction of asthmatics are smokers. However, clinical trials studying new drugs or newer therapeutic regimens for asthma generally exclude smokers. Therefore, there is a lack of specific information about the treatment of asthma in smokers. The asthmatic smoker is a special phenotype with important therapeutic and prognostic clinical implications. Any form of tobacco use, especially cigarette smoking, plays an important role in this disease. Asthmatic smokers are prone to several negative outcomes. Smoking cessation results in an improvement of symptoms and pulmonary functioning. Counselling and first-line medications for smoking cessation (nicotine replacement therapy, bupropion and varenicline) significantly increase quitting rates. The role of electronic cigarettes in this group of patients has only begun to be studied. The treatment of asthmatics that smoke has characteristics that need must be well understood by clinicians, especially the poor response to corticosteroids. This condition is not universal and physicians should always consider its inclusion in the treatment of these patients. The association of inhaled corticosteroids (ICS) plus a long-acting beta2 adrenegic (LABA) by smoking asthmatics results in more pronounced improvement in several asthma outcomes compared with the use of corticosteroid alone. Inhaled corticosteroids in extra-fine particles associated with LABA may be a new perspective of treatment. Also the use of leukotriene antagonists may become another therapeutic alternative. The purpose of this narrative review is to discuss the challenges faced by clinicians to control asthma in smokers and to present methods of coping with smoking treatment and avoiding relapses.

Janeva E, Arsovska A, Isjanovski V. The influence of inhaled corticosteroids on asthma control test in smokers and non-smokers with asthma

Smoking in asthmatics is responsible for the worsening of asthma symptoms, more frequent asthma exacerbations and hospitalizations and lowered quality of life. In smoking asthmatics the designated doses of the inhaled corticosteroid treatment are usually insufficient to accomplish total asthma control. Out of 54 screened adult patients up to 50 years old with mild asthma, 38 were involved in the study. They were divided in two groups: smokers and non-smokers. They received a total daily dosage of 500 µg of inhaled fluticasone propionate. A rescue medication, a short-acting ß2 agonist (salbutamol) in a dosage of 0.1 mg/per inhaled dose, was used when needed. Asthma was diagnosed by a positive metacholine provocation test and/or a positive bronchodilatator response. An asthma control test i.e. the ACT-TM questionnaire was performed before the beginning of the study and 6 weeks after the treatment with fluticasone propionate of the previous corticosteroid-naive patients. A statistically positive response (p<0.05) was reached in favor of non-smoking asthmatics. It can be concluded that ACT is a reliable tool to assess the effect of the topical corticosteroid treatment in non-smoking and smoking asthmatics. An achievement of better asthma control could be expected among both of the examined groups, but the effect of the intervention in the therapy is estimated to be more expressed within the group of asthmatic non-smokers. In smoking asthmatics there is a need for other therapeutic modalities such as increasing the dosage of inhaled corticosteroids, usage of combination therapy and/or adding low doses of aminophylline.

Understanding variation in length of hospital stay for COPD exacerbation: European COPD audit

Chronic obstructive pulmonary disease (COPD) care across Europe has high heterogeneity with respect to cost and the services available. Variations in length of stay (LOS) may be attributed to patient characteristics, resource and organisational characteristics, and/or the so-called hospital cluster effect. The European COPD Audit in 13 countries included data from 16 018 hospitalised patients. The recorded variables included information on patient and disease characteristics, and resources available. Variables associated with LOS were evaluated by a multivariate, multilevel analysis. Mean±sd LOS was 8.7±8.3 days (median 7 days, interquartile range 4-11 days). Crude variability between countries was reduced after accounting for clinical factors and the clustering effect. The main factors associated with LOS being longer than the median were related to disease or exacerbation severity, including GOLD class IV (OR 1.77) and use of mechanical ventilation (OR 2.15). Few individual resource variables were associated with LOS after accounting for the hospital cluster effect. This study emphasises the importance of the patients' clinical severity at presentation in predicting LOS. Identifying patients at risk of a long hospital stay at admission and providing targeted interventions offers the potential to reduce LOS for these individuals. The complex interactions between factors and systems were more important that any single resource or organisational factor in determining differences in LOS between hospitals or countries.

Asthma risk factors

BACKGROUND

Bronchial asthma is one of the most common chronic diseases in childhood, with a current prevalence of 6% to 9%, but a prevalence that is increasing at an alarming rate. Asthma is a complex genetic disorder with strong environmental influence. It imposes a growing burden on our society in terms of morbidity, quality of life, and healthcare costs. Despite large-scale efforts, only a few asthma genes have been confirmed, suggesting that the genetic underpinning of asthma is highly complex.

METHODS

A review of the literature was performed regarding atopic and nonatopic asthma risk factors, including environmental risk factors and genetic studies in adults and children.

RESULTS

Several environmental risk factors have been identified to increase the risk of developing asthma such as exposure to air pollution and tobaccos smoke as well as occupational risk factors. In addition atopy, stress, and obesity all can increases the risk for asthma in genetically susceptible persons.

CONCLUSION

Asthma represents a dysfunctional interaction with our genes and the environment to which they are exposed, especially in fetal and early infant life. The increasing prevalence of asthma in all age groups indicate that our living environment and immunity are in imbalance with each other reacting with airway inflammation to the environmental exposures and often non-harmful proteins, such as allergens causing the current "asthma and allergy epidemic." Because of the close relationship between asthma and chronic rhinosinusitis, it is important that otolaryngologists have a good understanding of asthma, the etiologic factors associated with disease, and its evaluation and management.

Causes of chronic productive cough: An approach to management

A chronic 'productive' or 'wet' cough is a common presenting complaint for patients attending the adult respiratory clinic. Most reviews and guidelines suggest that the causes of a productive cough are the same as those of a non-productive cough and as such the same diagnostic pathway should be followed. We suggest a different diagnostic approach for patients with a productive cough, focussing on the conditions that are the most likely causes of this problem. This review is intended to briefly summarise the epidemiology, clinical features, pathophysiology and treatment of a number of conditions which are often associated with chronic productive cough to aid decision making when encountering a patient with this often distressing symptom. The conditions discussed include bronchiectasis, chronic bronchitis, asthma, eosinophilic bronchitis and immunodeficiency. We also propose an adult version of the paediatric diagnosis of protracted bacterial bronchitis (PBB) in patients with idiopathic chronic productive cough who appear to respond well to low dose macrolide therapy.

Poor symptom control is associated with reduced CT scan segmental airway lumen area in smokers with asthma

BACKGROUND

Cigarette smoking is associated with worse symptoms in asthma and abnormal segmental airways in healthy subjects. We tested the hypothesis that current symptom control in smokers with asthma is associated with altered segmental airway dimensions measured by CT scan.

METHODS

In 93 subjects with mild, moderate, and severe asthma (smokers and never smokers), we recorded Asthma Control Questionnaire-6 (ACQ-6) score, spirometry (FEV1; forced expiratory flow rate, midexpiratory phase [FEF(25%-75%)]), residual volume (RV), total lung capacity (TLC), and CT scan measures of the right bronchial (RB) and left bronchial (LB) segmental airway dimensions (wall thickness, mm; lumen area, mm²) in the RB3/LB3, RB6/LB6, and RB10/LB10 (smaller) airways.

RESULTS

The CT scan segmental airway (RB10 and LB10) lumen area was reduced in smokers with asthma compared with never smokers with asthma; RB10, 16.6 mm² (interquartile range, 12.4-19.2 mm²) vs 19.6 mm² (14.7-24.2 mm²) (P = .01); LB10, 14.8 mm² (12.1-19.0 mm²) vs 19.9 mm² (14.5-25.0 mm²) (P = .003), particularly in severe disease, with no differences in wall thickness or in larger airway (RB3 and LB3) dimensions. In smokers with asthma, a reduced lumen area in fifth-generation airways (RB10 or LB10) was associated with poor symptom control (higher ACQ-6 score) (-0.463 [-0.666 to -0.196], P = .001, and -0.401 [-0.619 to -0.126], P = .007, respectively) and reduced postbronchodilator FEF(25%-75%) (0.521 [0.292-0.694], P < .001, and [0.471 [0.236-0.654], P = .001, respectively) and higher RV/TLC %.

CONCLUSIONS

The CT scan segmental airway lumen area is reduced in smokers with asthma compared with never smokers with asthma, particularly in severe disease, and is associated with worse current symptom control and small airway dysfunction.

Statement on smoking cessation in COPD and other pulmonary diseases and in smokers with comorbidities who find it difficult to quit

Chronic obstructive pulmonary disease (COPD), lung cancer, asthma and pulmonary tuberculosis are common pulmonary diseases that are caused or worsened by tobacco smoking. Growing observational evidence suggests that symptoms and prognosis of these conditions improve upon smoking cessation. Despite increasing numbers of (small) randomised controlled trials suggesting intensive smoking cessation treatments work in people with pulmonary diseases many patients are not given specific advice on the benefits or referred for intensive cessation treatments and, therefore, continue smoking.This is a qualitative review regarding smoking cessation in patients with COPD and other pulmonary disorders, written by a group of European Respiratory Society experts. We describe the epidemiological links between smoking and pulmonary disorders, the evidence for benefits of stopping smoking, how best to assess tobacco dependence and what interventions currently work best to help pulmonary patients quit. Finally, we describe characteristics and management of any "hardcore" smoker who finds it difficult to quit with standard approaches.

Serum periostin in smokers and never smokers with asthma

BACKGROUND

Elevated serum periostin is associated with airway eosinophilia and may predict response to therapies targeting Th2 inflammation. Smoking in asthma is generally associated with non-eosinophilic airway inflammation and corticosteroid insensitivity. We determined the effect of smoking status on serum periostin in asthma.

METHODS

Serum periostin (ELISA; Aviscera Bioscience) was measured in 107 patients with stable asthma of different disease severity and 45 healthy controls. The effects on serum periostin of clinical indices including smoking status and of inflammatory biomarkers including sputum eosinophil count were analysed. Serum periostin was measured before and after two weeks of oral corticosteroids in a separate group of 33 non-smokers and smokers with stable asthma.

RESULTS

Serum periostin (median [IQR], ng/mL) was reduced in smokers with asthma compared to never smokers with asthma; 9 (9, 307) versus 233 (34, 1108) respectively, p = 0.017. Periostin was not influenced by disease severity (p = 0.786) or atopic status (p = 0.144). There was a weak correlation between serum periostin and sputum eosinophil count in smokers with asthma (r = 0.315, p = 0.020). The proportion of patients with an elevated serum periostin concentration was greater in never smokers with asthma compared to smokers with asthma [65% versus 39% respectively, p = 0.003]. Oral steroid treatment reduced serum periostin (p = 0.030) in non-smokers with asthma.

CONCLUSION

Despite lower median serum periostin concentrations in smokers with asthma compared to never smokers with asthma, approximately forty percent of this group had a high level. The potential value of a raised serum periostin concentration in predicting a beneficial response to therapies targeting Th2 inflammation in smokers with asthma requires to be investigated.

Developing and emerging clinical asthma phenotypes

For more than a century, clinicians have attempted to subdivide asthma into different phenotypes based on triggers that cause asthma attacks, the course of the disease, or the prognosis. The first phenotypes that were described included allergic asthma, intrinsic or nonallergic asthma, infectious asthma, and aspirin-exacerbated asthma. These phenotypes are being reviewed elsewhere in this issue of the journal. The present article focuses on developing and emerging clinical asthma phenotypes. First, asthma phenotypes that are associated with environmental exposures (occupational agents, cigarette smoke, air pollution, cold dry air); second, asthma phenotypes that are associated with specific symptoms or clinical characteristics (cough, obesity, adult onset of disease); and third, asthma phenotypes that are based on biomarkers. This latter approach is the most promising because it attempts to identify asthma phenotypes with different underlying mechanisms so that therapies can be better targeted toward disease-specific features and disease outcomes can be improved.

Smoking Behaviour of Asthmatic Patients in Primary Care: A Cross-Sectional Study

Introduction:

One-third of adult asthma patients smoke cigarettes despite smoking being a known trigger of asthma exacerbation. This study aims to describe the behaviour of asthmatic patients who smoke and explore the reasons why they continue to smoke cigarettes even when unwell.

Methods:

A cross-sectional questionnaire survey was conducted on adult asthma patients at primary care clinics in Singapore. One hundred and seventy-four asthmatic smokers (AS) of four ethnic groups, both genders, aged 21–50 years were recruited. Demographic data and smoking characteristics, reasons for smoking, and experiences during their attempts to quit were collected and analysed using the statistical software STATA version 12.

Results:

The median age of AS was 30 years. Seventy-five percent were males and mostly Malays (58%). Seventy-one percent had at least secondary education. Eighty-six percent started smoking before 20 years old. Ninety-eight percent smoked less than 10 sticks per day and 51% smoked ≤5 pack-years. Thirty-eight percent smoked within 5 minutes of awakening. AS cited reasons such as stress relief (79%), peer pressure (36%), influence from family members who smoke (40%), think better (35%), staying alert (57%), and relaxed (53%). Although 77% believed smoking worsened their asthma, they continued to smoke. Restlessness (43%), mood swings (27%), difficulties in concentration (25%) and irritability (24%) were common symptoms encountered in those who attempted to quit. About 44% did not refrain from smoking even when they were ill.

Conclusion:

Adult asthmatic smokers continued cigarette smoking to relieve stress, maintain mental alertness and avoid withdrawal symptoms. Implementing a programme to address smoking behaviour and withdrawal symptoms is paramount towards successful smoking cessation.

Assessment of asthma control: the SERENA study

BACKGROUND

Several studies suggest that many asthmatic subjects have uncontrolled asthma. The control of asthma is now considered the major goal of therapy.

OBJECTIVES

to ascertain the level of asthma control, by Asthma Control Test (ACT), in "real-life" clinical practice and the potential risk factors for uncontrolled disease in patients treated with inhaled corticosteroids (ICS) and long-acting beta-adrenergic agonists (LABA).

METHODS

SERENA is a multi-centre, cross-sectional, 6-month observational, non-interventional study carried out in 16 Pulmonary Units in Italy. Asthmatic outpatients aged over 18, undergoing treatment with ICS at medium-high daily doses associated with LABA, were enrolled. The patients were divided in 3 subgroups according to the level of asthma control by ACT score (25:controlled; 20-24:partly controlled; <20: uncontrolled).

RESULTS

Out of a total of 548 patients, 396 met the inclusion criteria. Only 9.1% of patients had asthma controlled, while partly controlled and uncontrolled asthma accounted for 39.6% and 51.3% respectively. The mean age was 54.5 ± 15.8 and the mean duration of asthma was 16.1 ± 14.1 years. There were more females than males (63% vs 37%) and females had highest prevalence of uncontrolled asthma (63.1%). The mean values of FEV1% predicted were lower in the uncontrolled group (p < 0.001). The percentage of patients with at least 1 exacerbation, unscheduled visit and/or admissions was lower in controlled (22.2%, 8.3%, 8.3%) than in partly controlled (50%, 38.6%, 9.2%) and uncontrolled (83.2%, 66.2%, 27.8%) groups (p < 0.0001). The multivariate ordinal logistic regression analysis identified female sex, FEV1 and exacerbations as the strongest independent factors associated with the uncontrolled disease.

CONCLUSION

This study highlights the importance in clinical practice of a periodic assessment by a validated asthma control instrument and exacerbations/health care contacts during previous year. Clinicians should be aware that a significant proportion of patients can have uncontrolled asthma, despite regular pharmacological treatment.

Chronic cough and sputum production are associated with worse clinical outcomes in stable asthma

BACKGROUND

Chronic cough and sputum production (chronic mucus hypersecretion) is a poorly described clinical feature of asthma. Our objective was to identify clinical, immunological and computed tomography (CT) measures of airway wall dimensions associated with these symptoms in smokers and never smokers with asthma.

METHODS

Cross-sectional data was analysed from 120 smokers and never smokers with asthma. Participants with and without a history of chronic mucus hypersecretion were compared for clinical outcomes, sputum differential cell counts and CT measures of airway dimensions (wall thickness, luminal area and percent wall area).

RESULTS

Chronic mucus hypersecretion occurred in a higher proportion of smokers with asthma (56%) than never smokers with asthma (20%), (p < 0.001) and the proportion of patients with these symptoms increased with asthma severity (p = 0.003). Smokers with asthma and chronic mucus hypersecretion had worse current clinical control than smokers without those symptoms [ACQ score 2.3 versus 1.6, p = 0.002]. A greater proportion of never smokers with chronic mucus hypersecretion required short courses of oral corticosteroids in the last year (58% versus 19%, p = 0.011). Sputum neutrophil and eosinophil counts were similar in asthma patients with or without chronic mucus hypersecretion. Of those with severe asthma and chronic mucus hypersecretion, a CT measure of airway lumen area was reduced in smokers compared to never smokers (11.4 mm(2) versus 18.4 mm(2); p = 0.017).

CONCLUSIONS

Chronic mucus hypersecretion occurs frequently in adults with stable asthma, particularly in smokers with severe disease and is associated with worse current clinical control in smokers and more exacerbations in never smokers.

Obesity-associated severe asthma represents a distinct clinical phenotype: analysis of the British Thoracic Society Difficult Asthma Registry Patient cohort according to BMI

BACKGROUND

Obesity has emerged as a risk factor for the development of asthma and it may also influence asthma control and airway inflammation. However, the role of obesity in severe asthma remains unclear. Thus, our objective was to explore the association between obesity (defied by BMI) and severe asthma.

METHODS

Data from the British Thoracic Society Difficult Asthma Registry were used to compare patient demographics, disease characteristics, and health-care utilization among three BMI categories (normal weight: 18.5-24.99; overweight: 25-29.99; obese: 30) in a well-characterized group of adults with severe asthma.

RESULTS

The study population consisted of 666 patients with severe asthma; the group had a median BMI of 29.8 (interquartile range, 22.5-34.0). The obese group exhibited greater asthma medication requirements in terms of maintenance corticosteroid therapy (48.9% vs 40.4% and 34.5% in the overweight and normal-weight groups, respectively), steroid burst therapy, and short-acting b 2 -agonist use per day. Significant differences were seen with gastroesophageal reflux disease (53.9% vs 48.1% and 39.7% in the overweight and normal weight groups, respectively) and proton pump inhibitor use. Bone density scores were higher in the obese group, while pulmonary function testing revealed a reduced FVC and elevated carbon monoxide transfer coefficient. Serum IgE levels decreased with increasing BMI and the obese group was more likely to report eczema, but less likely to have a history of nasal polyps.

CONCLUSIONS

Patients with severe asthma display particular characteristics according to BMI that support the view that obesity-associated severe asthma may represent a distinct clinical phenotype.

The coexistence of asthma and chronic obstructive pulmonary disease (COPD): prevalence and risk factors in young, middle-aged and elderly people from the general population

Background

The joint distribution of asthma and chronic obstructive pulmonary disease (COPD) has not been well described. This study aims at determining the prevalence of self-reported physician diagnoses of asthma, COPD and of the asthma-COPD overlap syndrome and to assess whether these conditions share a common set of risk factors.

Methods

A screening questionnaire on respiratory symptoms, diagnoses and risk factors was administered by mail or phone to random samples of the general Italian population aged 20–44 (n = 5163) 45–64 (n = 2167) and 65–84 (n = 1030) in the frame of the multicentre Gene Environment Interactions in Respiratory Diseases (GEIRD) study.

Results

A physician diagnosis of asthma or COPD (emphysema/chronic bronchitis/COPD) was reported by 13% and 21% of subjects aged <65 and 65–84 years respectively. Aging was associated with a marked decrease in the prevalence of diagnosed asthma (from 8.2% to 1.6%) and with a marked increase in the prevalence of diagnosed COPD (from 3.3% to 13.3%). The prevalence of the overlap of asthma and COPD was 1.6% (1.3%–2.0%), 2.1% (1.5%–2.8%) and 4.5% (3.2%–5.9%) in the 20–44, 45–64 and 65–84 age groups. Subjects with both asthma and COPD diagnoses were more likely to have respiratory symptoms, physical impairment, and to report hospital admissions compared to asthma or COPD alone (p<0.01). Age, sex, education and smoking showed different and sometimes opposite associations with the three conditions.

Conclusion

Asthma and COPD are common in the general population, and they coexist in a substantial proportion of subjects. The asthma-COPD overlap syndrome represents an important clinical phenotype that deserves more medical attention and further research.

CD8(+) T cells characterize early smoking-related airway pathology in patients with asthma

BACKGROUND

Smoking in asthma occurs frequently and is associated with increased symptom severity, an impaired response to corticosteroids, and accelerated lung function decline. Airway pathology in smoking asthmatics is characterized by neutrophilia and epithelial changes such as goblet cell hyperplasia and increased proliferation. Bronchial CD8(+) T cells are implicated in lung function decline in asthma and COPD. We hypothesized that smoking modifies airway inflammation in asthma by increasing the number of CD8(+) T cells at an early stage.

OBJECTIVES & METHODS

To study effects of smoking on airway pathology in bronchial biopsies from atopic patients with controlled intermittent or mild persistent asthma (12 smokers, 9.7 py and 11 never-smokers, 0.0 py; 20-50 yrs; FEV1 > 70% predicted; PC20MCh < 8 mg/mL, no ICS) using immunohistochemistry.

RESULTS

Smoking asthmatics showed higher numbers of bronchial CD8(+) T cells (55.8 vs 23.9 cells/0.1 mm(2); p = 0.001) and CD68(+) macrophages (7.5 vs 4.6 cells/0.1 mm(2), p = 0.012), and a lower CD4(+)/CD8(+) cell ratio (0.16 vs 0.40; p = 0.007) compared with non-smoking asthmatics, but no difference in neutrophils. Furthermore, the % intact epithelium was higher in smoking asthmatics (49.3 vs 23.3, p = 0.001).

CONCLUSION

Smoking asthmatics with a limited smoking history show a distinct pattern of airway pathology characterized by a bronchial infiltrate of CD8(+) T cells and CD68(+) macrophages, and epithelial remodelling resembling COPD-like features. This raises the hypothesis that early presence of CD8(+) T cells contributes to disease progression in smoking asthmatics.

The role of smoking in allergy and asthma: lessons from the ECRHS

The European Community Respiratory Health Survey is an international multicenter cohort study of asthma, allergy, and lung function that began in the early-1990s with recruitment of population-based samples of 20- to 44-year-old adults, mainly in Europe. The aims of the study are broad ranging but include assessment of the role of in utero exposure to tobacco smoke, exposure to environmental tobacco smoke, and active smoking on the incidence, prevalence, and prognosis of allergy and asthma. Cross-sectional and longitudinal analyses looking at these associations have been conducted, sometimes only using information collected in one country, and on other occasions using information collected in all the participating centers. This article summarizes the results from these various publications from this large epidemiologic study.

Clinical outcomes and inflammatory biomarkers in current smokers and exsmokers with severe asthma

BACKGROUND

Clinical outcomes are worse in current smokers and exsmokers with mild-to-moderate asthma compared with never smokers, but little is known about the influence of smoking status in patients with severe asthma.

OBJECTIVES

We sought to examine the association of current or previous cigarette smoking with clinical and inflammatory variables in patients with severe asthma.

METHODS

We compared patients' demographics, disease characteristics, and biomarkers of inflammation in current smokers (n=69 [9%]), exsmokers (n=210 [28%]), and never smokers (n=461 [62%]) with severe asthma (n=760) recruited to the British Thoracic Society Severe Asthma Registry.

RESULTS

Current smokers had poorer asthma control, more unscheduled health care visits, more rescue courses of oral steroids, and higher anxiety and depression scale scores than exsmokers or never smokers. Current smokers had a reduced proportion of sputum eosinophils compared with never smokers (1% and 4%, respectively) and lower fraction of expired nitric oxide (50 mL/s; 14 ppb and 35 ppb, respectively). Exsmokers compared with never smokers had an increased proportion of sputum neutrophils (59% and 43%, respectively) but a similar proportion of sputum eosinophils (3%) and fraction of expired nitric oxide (50 mL/s; 35 ppb). Both current smokers and exsmokers had reduced serum specific IgE levels to several common environmental allergens.

CONCLUSION

Current smokers with severe asthma exhibit worse clinical and health care outcomes compared with exsmokers and never smokers with severe asthma. Their inflammatory profiles in sputum and blood differ.