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

Effect of asthma control on general health-related quality of life in patients diagnosed with adult-onset asthma

Health-related quality of life (HRQoL) is a well-established aspect of health that can be measured by both disease-specific and general instruments. The effect of uncontrolled asthma on generic HRQoL has not been shown in patients with clinically confirmed adult-onset asthma and with asthma control defined according to the Global Initiative for Asthma, so the aim of this study was to determine this. In the 12-year follow-up cohort of the Seinäjoki Adult Asthma Study (n = 203), patients with uncontrolled and partially controlled asthma had lower generic HRQoL as determined by 15D compared to the controlled group. On 10 out of 15 dimensions of 15D, the mean scores were significantly lower in patients with uncontrolled asthma compared with those with controlled asthma. The affected dimensions were mobility, breathing, sleeping, usual activities, mental function, discomfort and symptoms, depression, distress, vitality and sexual activity. In the Tobit regression analysis, a poorer 15D score was associated with uncontrolled asthma, lower postbronchodilator FEV₁, female sex, depression, treated dyspepsia and poorer 15D score at diagnosis. Our results show that uncontrolled asthma affects everyday life in several aspects, including previously unknown components such as sexual activity and vitality.

Occupational exposures and asthma-COPD overlap in a clinical cohort of adult-onset asthma

Occupational exposure to vapours, gases, dusts or fumes (VGDF) increases the prevalence of asthma-COPD overlap (ACO) in adult-onset asthma. VGDF exposure is independently associated with ACO and an additive effect with smoking is proposed. http://bit.ly/2LiMiXW.

Impact of thyroid hormones on asthma in older adults

Objective

Thyroid hormones affect airway contraction, but the specific effects of thyroid hormones on airways are controversial.

Methods

We divided 78 advanced-age men with asthma into 3 groups: type I respiratory failure (RF1), type II respiratory failure (RF2), and no respiratory failure (NRF). Pulmonary function was measured after asthma stabilization.

Results

The free triiodothyronine (FT3) level was significantly higher in the RF1 than RF2 group, but the free thyroxine (FT4), total thyroxine (TT4), and thyroid-stimulating hormone (TSH) levels were not significantly different. In the RF1, RF2, and NRF groups, the correlation coefficients between FT3 and the forced expiratory volume in1 s (FEV₁) were 0.317, 0.627, and 0.213; those between FT3 and the FEV₁/forced vital capacity (FVC) ratio were 0.287, 0.412, and 0.156; those between FT4 and FEV₁ were 0.214, 0.231, and 0.167; and those between FT4 and the FEV₁/FVC ratio were 0.211, 0.215, and 0.218, respectively. In the RF1 and RF2 groups, the correlation coefficients between the sum activity of peripheral deiodinases (SPINA-GD) and the FEV₁/FVC ratio were 0.164 and 0.421, and those between SPINA-GD and FEV₁ were 0.284 and 0.491, respectively.

Conclusion

The correlation between FT3 and pulmonary function is likely caused by changes in thyroid enzymology.

Effects of short-term smoking on lung function and airway hyper-responsiveness in young patients with untreated intermittent adult-onset asthma: retrospective cross-sectional study at a primary-tertiary care hospital in Japan

OBJECTIVE

In daily clinical practice, smokers with asthma and with intermittent disease severity are frequently encountered. The effects of short-term smoking on lung function or disease presentation in younger patients with intermittent adult-onset asthma remain unclear. We sought to clarify the effects of short-term smoking (<10 pack-years) on lung function and airway hyper-responsiveness (AHR) in young patients with untreated intermittent adult-onset asthma.

DESIGN

Retrospective, cross-sectional study.

SETTING

A single primary-tertiary medical centre in Japan.

PARTICIPANTS

From patients who underwent bronchodilator reversibility tests between January 2004 and March 2011 (n=7291), 262 consecutive patients (age, 20-34 years) with untreated intermittent adult-onset asthma, including 157 never smokers and 105 current smokers within 10 pack-years, were analysed.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the association of the daily smoking frequency (number of cigarettes per day), smoking duration (years) and cumulative smoking history (pack-years) with postbronchodilator lung function. The secondary outcome was the association of the former three smoking parameters with AHR.

RESULTS

The daily smoking frequency, smoking duration and cumulative smoking history were significantly associated with decreased postbronchodilator lung function. Daily smoking of ≥11 cigarettes per day was also associated with marked AHR (OR 2.23; 95% CI 1.03 to 4.80), even after adjustment for age, sex, disease duration and body mass index.

CONCLUSION

Short-term active smoking in early adulthood may be associated with decreased lung function and AHR, even in patients with intermittent adult-onset asthma. Our findings suggest a benefit of never smoking, even for young patients with intermittent adult-onset asthma.

Smoking and lung function among adults with newly onset asthma

Introduction

Smoking increases the risk of asthma and reduces lung function among subjects with and without asthma. We assessed the effects of smoking on lung function reflecting both central and small airways among adults with newly onset asthma.

Methods

In a population-based study, 521 (response rate 86%) working-aged adults with clinically defined newly diagnosed asthma answered a questionnaire on personal smoking and other factors potentially influencing lung function, and performed spirometry. We applied multiple linear regression analysis to estimate the relations between smoking and lung function adjusting for confounding.

Results

Among asthmatics, FEV₁ level was reduced significantly, on average 208 mL, related to regular smoking (adjusted effect estimate −0.208, 95% CI −0.355 to −0.061) and 245 mL in relation to former smoking, that is, among those who quit less than a year ago (−0.245, 95% CI −0.485 to −0.004). In contrast, FEV₁ was not significantly related to occasional smoking or former smoking among those who quit over a year ago. Forced expiratory flow (FEF) levels (L/s) were also significantly reduced among regular smokers (FEF_25–75%: −0.372, 95% CI −0.607 to −0.137; FEF_50%: −0.476, 95% CI −0.750 to −0.202). An exposure–response pattern related to both daily smoking rate and lifetime cumulative smoking was seen both among men and women.

Conclusions

This study provides new evidence that among working-aged adults with new asthma, regular smoking and former smoking reduce lung function levels with a dose–response pattern. The lung function parameters applied as outcomes reflect both larger and smaller airways.

Nonallergic Triggers and Comorbidities in Asthma Exacerbations and Disease Severity

Asthma triggers are exogenous or endogenous factors that could worsen asthma acutely to cause an exacerbation, or perpetuate chronic symptoms and airflow limitation. Because it is well known that recent asthma exacerbations and poor symptom control are strong predictors of future disease activity, it is not surprising that the number of (allergic or nonallergic) asthma triggers in the environment correlates with the disease-related quality of life. There is a need to identify and avoid specific triggers as the centerpiece of disease management, especially in those with heightened sensitivity to certain factors.

Daily physical activity and lung function decline in adult-onset asthma: a 12-year follow-up study

Background: There is a lack of knowledge on the association between daily physical activity and lung function in patients with asthma.

Objective: This study aims to examine the association between daily physical activity and asthma control, lung function, and lung function decline in patients with adult-onset asthma.

Design: This study is part of Seinäjoki Adult Asthma Study (SAAS), where 201 patients were followed for 12 years after asthma diagnosis. Daily physical activity was assessed at follow-up by a structured questionnaire and used to classify the population into subgroups of low (≤240 min) or high (>240 min) physical activity. Three spirometry evaluation points were used: 1. diagnosis, 2. the maximum lung function during the first 2.5 years after diagnosis (Max_0-2.5), 3. follow-up at 12 years.

Results: High physical activity group had slower annual FEV₁ (p<0.001) and FVC (p<0.018) decline. Additionally, the high physical activity group had higher FEV₁ values at follow-up, and higher FEV₁/FVC ratios at follow-up and diagnosis. There was no difference in BMI, smoking, medication, or frequency of physical exercise between high and low physical activity groups. Differences remained significant after adjustments for possible confounding factors.

Conclusion: This is the first demonstration of an association between long-term FEV₁ decline and daily physical activity in clinical asthma. Low physical activity is independently associated with faster decline in lung function. Daily physical activity should be recommended in treatment guidelines in asthma.

Movement behaviours are associated with lung function in middle-aged and older adults: a cross-sectional analysis of the Canadian longitudinal study on aging

Background

Physical activity has been shown to attenuate the age-associated decline in lung function; however, there is little research evaluating different movement behaviours as potential correlates of lung function. Modifiable determinants need to be identified, as the prevalence of chronic respiratory disease is on the rise. The purpose of this study was to investigate associations of self-reported movement behaviours (i.e., sitting time, walking, different intensities of physical activity, and strengthening activities), with lung function in middle-aged and older adults without a respiratory disease, according to their smoking history.

Methods

Data from participants of the Canadian Longitudinal Study on Aging were used for analysis (n = 16,839). Lung function was assessed using spirometry. A modified version of the Physical Activity Scale for the Elderly was used to assess sitting time and physical activity levels. Smoking status was classified as non-smoking, < 10 pack years smoking, and 10 or more pack years of smoking. The association between movement behaviours and lung function was assessed using hierarchical linear regression models with all covariates (age, sex, smoking status, body mass index, education, retirement status, and sleep duration) entered into block 1, and all movement behaviours entered into block 2.

Results

All movement behaviours were associated with Forced Expiratory Volume in 1 s (FEV₁) and Forced Vital Capacity (FVC) % predicted in crude and adjusted models, regardless of smoking status. Sitting time was negatively associated with both FEV_1%pred (β: -0.094, CI: -0.140, − 0.047) and FVC_%pred (β: -0.087, CI: -0.128, -0.045) among those who never smoked, and strength activity was positively associated with both FEV_1%pred (β: 0.272, CI: 0.048, 0.496) and FVC_%pred (β: 0.253, CI: 0.063,0.442) among those who smoked < 10 pack years, as well as with FVC_%pred among those who smoked 10 or more pack years (β: 0.309, CI: 0.064, 0.554).

Conclusions

This is the first study to assess the association of different movement behaviours with lung function among middle-aged and older adults without a respiratory disease. These findings indicate that movement behaviours are correlates of lung function, and that they may be modifiable determinants of the age-associated decline in lung function.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5739-4) contains supplementary material, which is available to authorized users.

Prevalence of Patients Eligible for Anti-IL-5 Treatment in a Cohort of Adult-Onset Asthma

BACKGROUND

Antibodies against the IL-5 pathway have been developed for the treatment of late-onset eosinophilic corticosteroid-resistant asthma. However, the prevalence of severe asthma and the proportion of patients who could benefit from such treatment among the general population of asthmatics remain unknown.

OBJECTIVE

To evaluate the prevalence and characteristics of patients eligible to anti-IL-5 treatment and severe asthma in an unselected cohort of adult-onset asthma.

METHODS

Seinäjoki Adult Asthma Study is a 12-year follow-up study of patients with new-onset adult asthma (n = 203). Prevalence was estimated based on information collected at 12-year follow-up visit. Health care use was collected from the whole 12-year follow-up period.

RESULTS

The prevalence of anti-IL-5-treatable patients was 2%, when the following criteria were used: daily use of medium-to-high inhaled corticosteroid (ICS) dose and long-acting β₂-agonist, ≥2 exacerbations/previous year and blood eosinophil count ≥300 cells/μL or fraction of exhaled nitric oxide ≥ 50 ppb. The prevalence of severe asthma, as defined according to European Respiratory Society/American Thoracic Society, was 5.9%, and only 1 patient met criteria for both groups. When compared with anti-IL-5 eligible patients, severe asthmatics were more often current smokers at diagnosis, obese, used higher ICS dose, and had higher blood neutrophils 12 years after diagnosis. Both groups differed from nonsevere asthma by a higher number of all and unplanned respiratory-related visits to health care. Severe asthmatics showed the highest number of hospitalizations.

CONCLUSIONS

In a cohort of unselected consecutive patients with adult-onset asthma, 5.9% fulfilled criteria for severe asthma and 2% qualified for anti-IL-5 treatment. Both groups represent a high burden to health care and specifically targeted treatment could lead to lower use of health care at long term.

[The respiratory effects of smoking]

A marked increase in the morbidity and mortality of a large number of broncho-pulmonary diseases has been documented in relation to smoking. The influence of tobacco smoking on various respiratory conditions. is discussed: incidence, severity or natural history modification of some respiratory illnesses: obstructive lung diseases (COPD, asthma), lung cancer, bacterial, viral respiratory infections, with the impact of smoking on tuberculosis. Finally, the relationship of tobacco with diffuse interstitial lung disease: protective role of smoking (controversial in sarcoidosis, real in hypersensitivity pneumonitis). The benefits of smoking cessation are described.

The Effect of Hidden Female Smoking on the Association between Smoking and Asthma

BACKGROUND

The association between smoking and asthma remains controversial. In our previous study, we were not able to show an association between asthma and smoking in Korean adults. One Korean study demonstrated underreporting of smoking history by female adults. The aim of the present study was to investigate the effects of hidden female smoking on the association between asthma and smoking in Korean adults.

METHODS

Data were acquired from 23,483 men and women aged ≥19 years who participated in the Korean National Health and Nutrition Examination Surveys (KNHANES).

RESULTS

The prevalence of asthma was 1.5%, the self-reported smoking prevalence was 32.4%, and the cotinine-verified smoking prevalence was 30.3%. Of the male cotinine-verified smokers, 6.4% were self-reported nonsmokers (2.7% never smokers and 3.7% ex-smokers), whereas 48.8% of the female cotinine-verified smokers were self-reported nonsmokers (43.2% never smokers and 5.6% ex-smokers). In males, the adjusted odds ratio of the association between smoking and asthma was 0.738 (confidence interval, CI: 0.393-1.173) in self-reported and 0.767 (CI: 0.515-1.143) in cotinine-verified smoking; in females, the adjusted odds ratio was 1.945 (CI: 1.348-2.805) in self-reported and 1.531 (CI: 1.076-2.179) in cotinine-verified smoking.

CONCLUSIONS

Our study showed smoking was associated with asthma in females but not in males.

Nordic consensus statement on the systematic assessment and management of possible severe asthma in adults

Although a minority of asthma patients suffer from severe asthma, they represent a major clinical challenge in terms of poor symptom control despite high-dose treatment, risk of exacerbations, and side effects. Novel biological treatments may benefit patients with severe asthma, but are expensive, and are only effective in appropriately targeted patients. In some patients, symptoms are driven by other factors than asthma, and all patients with suspected severe asthma ('difficult asthma') should undergo systematic assessment, in order to differentiate between true severe asthma, and 'difficult-to-treat' patients, in whom poor control is related to factors such as poor adherence or co-morbidities. The Nordic Consensus Statement on severe asthma was developed by the Nordic Severe Asthma Network, consisting of members from Norway, Sweden, Finland, Denmark, Iceland and Estonia, including representatives from the respective national respiratory scientific societies with the aim to provide an overview and recommendations regarding the diagnosis, systematic assessment and management of severe asthma. Furthermore, the Consensus Statement proposes recommendations for the organization of severe asthma management in primary, secondary, and tertiary care.

Inhaled corticosteroids and asthma control in adult-onset asthma: 12-year follow-up study

BACKGROUND

Prescribed inhaled corticosteroid (ICS) doses in asthma have been studied in cross-sectional settings whereas long-term follow-up studies have not been carried out.

OBJECTIVE

To evaluate prescribed medication longitudinally by calculating cumulative ICS doses and dose changes in a cohort of new-onset adult asthma during 12 years and in different groups of asthma control.

METHODS

A total of 203 patients were followed for 12 years as part of Seinäjoki Adult Asthma Study (SAAS). All asthma-related visits and prescribed medication over the study period were collected from medical records.

RESULTS

Total cumulative ICS dose for the 12-year follow-up period was 3.4g (±SEM 0.1) per patient. Both respiratory specialists and GPs prescribed step-ups and step-downs in ICS treatment and in total 649 dose changes were noted during the follow-up (median 3(1-5) per patient). Patients with uncontrolled asthma received higher ICS doses throughout the follow-up period, and therefore, cumulative 12-year ICS dose (3.8g ± SEM 0.2) in this group was higher than that in those with partially controlled (3.4g ± SEM 0.2) or controlled disease (2.9g ± SEM 0.2) (p = 0.0001). Patients with uncontrolled asthma were also prescribed a higher number of ICS dose changes than patients with controlled disease.

CONCLUSION

Despite frequent dose changes and high ICS doses during the 12-year follow-up, the level of asthma control remained poor in patients with uncontrolled asthma. This suggests that high ICS doses may not be effective enough for management of disease in patients with uncontrolled adult-onset asthma and novel targeted treatments are required.

Predictors of accelerated decline in lung function in adult-onset asthma

Little is known about the prognosis of adults with new-onset asthma. Cross-sectional studies suggest that these patients may exhibit accelerated decline in forced expiratory volume in 1 s (FEV₁). However, risk factors for accelerated decline in lung function have not yet been identified.We aimed to identify these risk factors in a prospective 5-year follow-up study in 200 adults with newly diagnosed asthma. In the current study, clinical, functional and inflammatory parameters were assessed annually for 5 years. Linear mixed-effects models were used to identify predictors.Evaluable lung function sets of 141 patients were available. Median (interquartile range) change in post-bronchodilator FEV₁ was -17.5 (-54.2 to +22.4) mL per year. Accelerated decline in FEV₁ was defined by the lower quartile of decline (>54.2 mL per year). Nasal polyps, number of blood and sputum eosinophils, body mass index, and level of exhaled nitric oxide were univariably associated with decline in lung function. Only the latter two were independently associated. Using cut-off values to identify patients at highest risk showed accelerated decline in FEV₁ in all patients with combined exhaled nitric oxide fraction (F_eNO) ≥57 ppb and body mass index (BMI) ≤23 kg·m^-2We conclude that adults with new-onset asthma with both high levels of exhaled nitric oxide and low BMI are at risk of accelerated decline in lung function.

Late-onset asthma: current perspectives

Because the pathophysiology of asthma has diverse characteristics, to manage the disease effectively, it is important for clinicians to distinguish among the clinical phenotypes. Among them, adult-onset asthma, that is, late-onset asthma (LOA), is increasing because of the aging of the population. The phenotype of LOA is largely divided into two types according to the presence or absence of eosinophilic inflammation, T-helper (Th)2- and non-Th2-associated LOA. Especially in Th2 LOA related to rhinosinusitis, as pulmonary function at onset is poor and asthma exacerbations occur frequently, it is important to detect this phenotype in the early phase by using a biomarker of Th2-type inflammation such as fractional exhaled nitric oxide (FENO). As non-Th2-LOA is often resistant to corticosteroids, this phenotype often requires another treatment strategy such as macrolide, diet, or smoking cessation. We often struggle with the management of LOA patients due to a lack of evidence; therefore, the elucidation of the mechanism of LOA contributes to increased efficiency of diagnosis and treatment of LOA. Age-related immune system and structural changes are thought to be associated with the pathophysiology of LOA. In the former case, changes in inflammatory cell function such as variations in the innate immune response and acquisition of autoimmunity or upregulation of oxidative stress are thought to be involved in the mechanism. Meanwhile, the latter can also become triggers or exacerbating factors of LOA via enhancement of airway hyperresponsiveness, decline in lung function, increased air trapping, and reduction in chest wall compliance. Therefore, appropriate individualized management in LOA may be possible through precisely assessing the pathophysiology based on age-related functional changes, including the immune and structural system.

Review of biomarkers to assess the effects of switching from cigarettes to modified risk tobacco products

Context: One approach to reducing the harm caused by cigarette smoking, at both individual and population level, is to develop, assess and commercialize modified risk alternatives that adult smokers can switch to. Studies to demonstrate the exposure and risk reduction potential of such products generally involve the measuring of biomarkers, of both exposure and effect, sampled in various biological matrices.Objective: In this review, we detail the pros and cons for using several biomarkers as indicators of effects of changing from conventional cigarettes to modified risk products.Materials and methods: English language publications between 2008 and 2017 were retrieved from PubMed using the same search criteria for each of the 25 assessed biomarkers. Nine exclusion criteria were applied to exclude non-relevant publications.Results: A total of 8876 articles were retrieved (of which 7476 were excluded according to the exclusion criteria). The literature indicates that not all assessed biomarkers return to baseline levels following smoking cessation during the study periods but that nine had potential for use in medium to long-term studies.Discussion and conclusion: In clinical studies, it is important to choose biomarkers that show the biological effect of cessation within the duration of the study.

Identification and validation of asthma phenotypes in Chinese population using cluster analysis

BACKGROUND

Asthma is a heterogeneous airway disease, so it is crucial to clearly identify clinical phenotypes to achieve better asthma management.

OBJECTIVE

To identify and prospectively validate asthma clusters in a Chinese population.

METHODS

Two hundred eighty-four patients were consecutively recruited and 18 sociodemographic and clinical variables were collected. Hierarchical cluster analysis was performed by the Ward method followed by k-means cluster analysis. Then, a prospective 12-month cohort study was used to validate the identified clusters.

RESULTS

Five clusters were successfully identified. Clusters 1 (n = 71) and 3 (n = 81) were mild asthma phenotypes with slight airway obstruction and low exacerbation risk, but with a sex differential. Cluster 2 (n = 65) described an "allergic" phenotype, cluster 4 (n = 33) featured a "fixed airflow limitation" phenotype with smoking, and cluster 5 (n = 34) was a "low socioeconomic status" phenotype. Patients in clusters 2, 4, and 5 had distinctly lower socioeconomic status and more psychological symptoms. Cluster 2 had a significantly increased risk of exacerbations (risk ratio [RR] 1.13, 95% confidence interval [CI] 1.03-1.25), unplanned visits for asthma (RR 1.98, 95% CI 1.07-3.66), and emergency visits for asthma (RR 7.17, 95% CI 1.26-40.80). Cluster 4 had an increased risk of unplanned visits (RR 2.22, 95% CI 1.02-4.81), and cluster 5 had increased emergency visits (RR 12.72, 95% CI 1.95-69.78). Kaplan-Meier analysis confirmed that cluster grouping was predictive of time to the first asthma exacerbation, unplanned visit, emergency visit, and hospital admission (P < .0001 for all comparisons).

CONCLUSION

We identified 3 clinical clusters as "allergic asthma," "fixed airflow limitation," and "low socioeconomic status" phenotypes that are at high risk of severe asthma exacerbations and that have management implications for clinical practice in developing countries.

Association of asthma with coronary heart disease: A meta analysis of 11 trials

PURPOSE

While the relationship of asthma and coronary heart disease (CHD) (a specific manifestation of cardiovascular disease) has not been described consistently, we tried to defined this relation and explore the influence of gender and asthma status (child- and adult-onset asthma) on this issue.

METHODS

We searched published reports that described the relationship of asthma and CHD.

RESULTS

Eleven trials were identified, covering 666,355 subjects. Asthma overall was significantly associated with CHD both for prospective trials (HR 1.34 [1.09,1.64], P = 0.005) and for retrospective trials(OR 1.29 [1.13,1.46], P = 0.001), when compared to individuals without asthma. Subgroup analysis split by gender indicated that females with asthma were significantly associated with CHD (HR 1.40 [1.20,1.62], P<0.001), but males with asthma were not significantly related with CHD (HR 1.19 [0.98,1.44], P = 0.07). For the four subgroups (Females with adult-onset asthma,males with adult-onset asthma,females with child-onset asthma,and males with child-onset asthma), pooled analysis of two trials indicated that only females with adult-onset asthma were significantly associated with CHD (HR 2.06 [1.32,3.19], P<0.001).

CONCLUSIONS

Our data indicated that asthma was associated with CHD, and the relationship between them seemed to derived mostly from females with adult-onset asthma. Considering the limits of our study, these findings should be taken with caution.

Differences between asthma-COPD overlap syndrome and adult-onset asthma

Differences between asthma-COPD overlap syndrome (ACOS) and adult-onset asthma are poorly understood. This study aimed to evaluate these differences in a clinical cohort of patients with adult-onset asthma, as a part of the Seinäjoki Adult Asthma Study (SAAS).188 patients were diagnosed with adult-onset asthma and re-evaluated 12 years after diagnosis. They were divided into three groups based on smoking history and post bronchodilator spirometry values: 1) never- and ex-smokers with <10 smoked pack-years; 2) non-obstructive (forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ≥0.7) patients with ≥10 pack-years; and 3) ACOS patients with ≥10 pack-years and FEV₁/FVC <0.7.ACOS patients had lower diffusing capacity (D_LCO/V_A 86% predicted versus 98 or 96% predicted; p<0.001), higher blood neutrophil levels (4.50 versus 3.60 or 3.85×10⁹ L^-1; p=0.008), and higher IL-6 levels (2.88 versus 1.52 or 2.10 pg·mL^-1, p<0.001) as compared to never- and ex-smokers with <10 pack-years, or non-obstructive patients with ≥10 pack-years smoking history, respectively. ACOS patients also showed reduced lung function, higher remaining bronchial reversibility and a higher number of comorbidities.This study shows distinct differences in diffusing capacity, blood neutrophil and IL-6 levels, bronchial reversibility, lung function and comorbidities between ACOS and adult-onset asthma. The present findings should be considered in the comprehensive assessment of adult asthma patients.

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.

Cluster Analysis on Longitudinal Data of Patients with Adult-Onset Asthma

BACKGROUND

Previous cluster analyses on asthma are based on cross-sectional data.

OBJECTIVE

To identify phenotypes of adult-onset asthma by using data from baseline (diagnostic) and 12-year follow-up visits.

METHODS

The Seinäjoki Adult Asthma Study is a 12-year follow-up study of patients with new-onset adult asthma. K-means cluster analysis was performed by using variables from baseline and follow-up visits on 171 patients to identify phenotypes.

RESULTS

Five clusters were identified. Patients in cluster 1 (n = 38) were predominantly nonatopic males with moderate smoking history at baseline. At follow-up, 40% of these patients had developed persistent obstruction but the number of patients with uncontrolled asthma (5%) and rhinitis (10%) was the lowest. Cluster 2 (n = 19) was characterized by older men with heavy smoking history, poor lung function, and persistent obstruction at baseline. At follow-up, these patients were mostly uncontrolled (84%) despite daily use of inhaled corticosteroid (ICS) with add-on therapy. Cluster 3 (n = 50) consisted mostly of nonsmoking females with good lung function at diagnosis/follow-up and well-controlled/partially controlled asthma at follow-up. Cluster 4 (n = 25) had obese and symptomatic patients at baseline/follow-up. At follow-up, these patients had several comorbidities (40% psychiatric disease) and were treated daily with ICS and add-on therapy. Patients in cluster 5 (n = 39) were mostly atopic and had the earliest onset of asthma, the highest blood eosinophils, and FEV₁ reversibility at diagnosis. At follow-up, these patients used the lowest ICS dose but 56% were well controlled.

CONCLUSIONS

Results can be used to predict outcomes of patients with adult-onset asthma and to aid in development of personalized therapy (NCT02733016 at ClinicalTrials.gov).