A 10 year follow up of 180 adults with bronchial asthma: factors important for the decline in lung function

Lung Function Decline in Adult Asthmatics-A 10-Year Follow-Up Retrospective and Prospective Study

Asthma may have an impact on lung function decline but conflicting results are reported in forced expiratory volume in one second (FEV₁) decline. We aimed to describe the changes in FEV₁ in lifelong non-smoking adult asthmatic outpatients during a 10-year follow-up comparing years 1–5 (1st period) with years 6–10 (2nd period) to assess factors affecting these changes. A total of 100 outpatients performed spirometry every 3 months during a 10-year survey. FEV₁/Ht³ slope values of the 2nd period reduced significantly respect to the 1st period (p < 0.0001). FEV₁ slopes of years 1–5 and 6–10 were inversely associated with FEV₁ at enrolment (p = 0.02, p = 0.01, respectively). Reversibility and variability FEV₁ showed a significant effect on the 1st period slopes (p = 0.01 and p < 0.04, respectively). Frequent exacerbators in the 1st year had steeper FEV₁/Ht³ slopes in the 1st period (p = 0.01). The number of subjects using higher doses of ICS was significantly lower at the 10th years respect to the 5th and the 1st year (p < 0.001, p = 0.003, respectively). This study shows that FEV₁ decline in treated adult asthmatics non-smokers, over 10-year follow-up, is not constant. In particular, it slows down over time, and is influenced by FEV₁ at enrolment, reversibility, variability FEV₁ and exacerbation score in the 1st year.

Blood eosinophil level and lung function trajectories: cross-sectional and longitudinal studies in European cohorts

Background

Elevated blood eosinophils have been associated with lower lung function and are believed to be associated with accelerated lung function decline.

Method

Blood eosinophils were measured in four cohorts: <45 years cohort within the Vlagtwedde–Vlaardingen (V&V) study, the Uppsala cohort of the European Community Respiratory Health Survey (ECRHS-Uppsala; <45 years), ≥45 years cohort within the V&V study, and the Rotterdam study (≥45 years). Blood eosinophils at baseline were classified as normal (<300 cells·μL⁻¹) or elevated (≥300 cells·μL⁻¹). Lung function was measured at baseline and follow-up with spirometry: forced expiratory volume in 1 s (FEV₁), vital capacity (VC) and their ratio FEV₁/VC. The association between blood eosinophils and lung function was tested cross-sectionally using linear regression and longitudinally using a mixed model, both adjusted for age, sex, height, pack-years smoking and smoking status. Stratified analyses were done for asthma.

Results

Elevated blood eosinophils were associated with lower FEV₁ (regression coefficient −147 mL (95% CI −188 to −105 mL)), VC (−120 mL (−165 to −75 mL)) and FEV₁/VC (−1.3% (−1.9% to −0.6%)) at baseline in the two <45 years cohorts, and with lower FEV₁ (−70 mL (−112 to −27 mL)) and FEV₁/VC (−1.8% (−2.6% to −1.0%)) in the two ≥45 years cohorts. Elevated blood eosinophils were associated with an accelerated decline in FEV₁ (−5.5 mL·year⁻¹ (95% CI −10.5 to −0.5 mL·year⁻¹)) and VC (−6.4 mL·year⁻¹ (−11.26 to −1.5 mL·year⁻¹)) compared to normal blood eosinophils in the younger asthmatic subjects in the longitudinal studies.

Conclusion

Elevated blood eosinophils are associated with lower lung function in the general population and with an accelerated lung function decline among asthmatic individuals.

Elevated blood eosinophils (≥300 cells per μL) associate with lower lung function in an adult general population and with a worse lung function trajectory in adult asthmatic individualshttps://bit.ly/3fJJ10h

Elevated eosinophils, IL5 and IL8 in induced sputum in asthma patients with accelerated FEV1 decline

BACKGROUND

Some patients with asthma present with accelerated lung function decline. This phenomenon is mostly associated with severe exacerbations and with poor asthma control.

OBJECTIVE

Our aim was to detect the extent of FEV1 decline in patients with mild asthma and to discriminate clinical, functional and inflammatory factors associated with accelerated FEV1 decline.

METHODS

We recruited 50 patients with mild asthma for pulmonary function testing and induced sputum sampling 12-15 years after the initial diagnosis. In 33 patients, from whom sputum of a good quality was obtained, inflammatory cells were counted and concentrations of cytokines IL-2, IL-4, IL-5, IL-8, IL-10, IFN-γ, angiogenin and VEGF in the sputum were measured by cytometric bead array.

RESULTS

Eighteen of 33 patients presented with accelerated FEV1 decline of more than 30 ml/year, with a mean (SEM) of 43.2 (3.9) ml/year, compared to 15 control patients with a FEV1 decline of 14.4 (2.1) ml/year. In the accelerated FEV1 decline group, we found elevated sputum levels of IL5 with a median (IQR) of 1.8 (0.4-3.2) pg/ml vs. 0.2 (0.1-1.2) pg/ml, p = 0.04; IL8 with a mean (SEM) of 1503 (194) pg/ml vs. 938 (177) pg/ml, p = 0.04; and eosinophils with a median (IQR) of 223 (41-1020) cells/μl vs. 39 (1-190) cells/μl, p = 0.03. No significant differences in other measured parameters were detected between the two groups.

CONCLUSION

Elevated sputum eosinophils, IL5 and IL8, which have a potential to stimulate airway remodelling, might be a useful non-invasive biomarkers and therapeutic targets of accelerated FEV1 decline in asthma patients.

Increase in blood eosinophils during follow-up is associated with lung function decline in adult asthma

BACKGROUND

Asthma is associated with accelerated rate of lung function (FEV₁) decline.

OBJECTIVE

To determine predictive factors associated with FEV₁ decline in adult asthma.

METHODS

A retrospective study was conducted in 229 asthmatics recruited from the University Asthma Clinic of Liege. Subjects had at least two visits with post-bronchodilation (post-BD) FEV₁ and minimum one year between them. A multivariable linear regression analysis was conducted in order to come up with factors associated with lung function decline.

RESULTS

Post-BD FEV₁ decline in % predicted. y^-1 was 0.2 (95%CI -2.0 to 2.8) in the overall population. Our population was made up of mild to moderate asthmatics [1] for 58%, aged 50 (41-60) years old, 62% were female and 59% were atopic. Median ICS dose was 1000 μg beclomethasone equivalent (CFC)/day with 81% treated at baseline. Time between visits was 46.8 ± 32.1 months. The univariate linear regression analysis revealed a negative association between % predicted FEV₁ decline and baseline ACQ (p < 0.0001) and blood eosinophils (% and/mm³) (p < 0.0001 and p < 0.0001). A positive association was found between % predicted FEV₁ decline and baseline pre-BD FEV1 (mL) values (p = 0.001), blood neutrophils (%) (p = 0.02), change in blood eosinophils (%) (p < 0.0001), time between visits (months) (p < 0.0001). The predictive variables for accelerated decline highlighted by the multivariable analysis (r² = 0.39) were change in blood eosinophils (%) over time (p = 0.002) and time between visits (months) (p < 0.0001).

CONCLUSION

These findings highlight a new value for blood eosinophil counts as their increase over time predicts greater lung function decline in asthma.

Associations between blood eosinophils and decline in lung function among adults with and without asthma

Eosinophilic inflammation and airway remodelling are characteristic features of asthma, but the association between them is unclear. We assessed associations between blood eosinophils and lung function decline in a population-based cohort of young adults.We used linear mixed models to analyse associations between blood eosinophils and spirometry at 21, 26, 32 and 38 years adjusting for sex, smoking, asthma and spirometry at age 18 years. We further analysed associations between mean eosinophil counts and changes in spirometry from ages 21 to 38 years.Higher eosinophils were associated with lower forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ratios and lower FEV₁ % predicted values for both pre- and post-bronchodilator spirometry (all p-values ≤0.048). Although eosinophil counts were higher in participants with asthma, the associations between eosinophils and spirometry were similar among participants without asthma or wheeze. Participants with mean eosinophil counts >0.4×10⁹ cells·L^-1 between 21 and 38 years had greater declines in FEV₁/FVC ratios (difference 1.8%, 95% CI 0.7-2.9%; p=0.001) and FEV₁ values (difference 3.4% pred, 95% CI 1.5-5.4% pred); p=0.001) than those with lower counts.Blood eosinophils are associated with airflow obstruction and enhanced decline in lung function, independently of asthma and smoking. Eosinophilia is a risk factor for airflow obstruction even in those without symptoms.

Low Variability in Peak Expiratory Flow Predicts Successful Inhaled Corticosteroid Step-Down in Adults with Asthma

BACKGROUND

The prognosis for patients beyond 1 year after reduction of their inhaled corticosteroid (ICS) dose remains unknown. Predictive factors that can be evaluated before the initiation of asthma treatment or at ICS dose reduction are unknown.

METHODS

We prospectively studied 223 patients in 6 hospitals in the National Hospital Organization of Japan during the 36 months after 50% reduction of their daily ICS dose. All patients recorded their morning and evening peak expiratory flows (PEFs) in their diaries. Lung function, bronchial hyperresponsiveness, fractional nitric oxide levels, number of eosinophils in sputum, and serum IgE levels were measured in most patients. Serum levels of IL-10, IL-33, and thymic stromal lymphopoietin before ICS dose reduction were measured in all patients.

RESULTS

During the 36-month study period, asthma control was retained in 127 (59.6%) of the 213 enrolled patients who underwent ICS dose reduction. Multivariate logistic regression analysis revealed that, at the initiation of dose reduction, the factors most predictive of maintenance of asthma control after ICS dose reduction were a low serum IL-33 level (P < .01), low PEF variability over 1 week (P = .014), childhood onset of asthma (at age <10 years) (P = .03), and high serum IL-10 level (P = .035).

CONCLUSIONS

We demonstrated that low PEF variability over 1 week, high serum IL-10 level, and low serum IL-33 concentration were useful factors for predicting that an adult's asthma will remain in control for months to years after a 50% reduction in the daily ICS dose.

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.

A 12-year prognosis of adult-onset asthma: Seinäjoki Adult Asthma Study

RATIONALE

Long-term prognosis of adult-onset asthma is poorly known.

OBJECTIVE

To evaluate 12-year prognosis of adult-onset asthma and the factors associated with disease prognosis.

METHODS

Seinäjoki Adult-onset Asthma Study (SAAS) is a 12-year real-life single-center follow-up study of new-onset asthma diagnosed at adult age and treated in primary and specialized care. Remission was defined by no symptoms and no asthma medication use for 6 months. Asthma control was evaluated according to Global Initiative for Asthma 2010. Factors associated with current asthma control were analyzed by multinomial multivariate logistic regression.

MAIN RESULTS

A total of 203 patients (79% of the baseline population) were followed for 12 years. Remission occurred in 6 (3%) patients. In 34% asthma was controlled, in 36% it was partially controlled and in 30% uncontrolled. Uncontrolled asthma was predicted by elevated body-mass index at baseline, smoking (pack-years) and current allergic or persistent rhinitis. Elevated blood eosinophils and good lung function (FEV1) at baseline protected from uncontrolled asthma. In contrast, gender, age at the onset or baseline symptoms (Airways Questionnaire 20) were not significant predictors of uncontrolled disease.

CONCLUSIONS

During a 12-year follow-up, remission of adult-onset asthma was rare occurring in only 3% of patients. The majority of patients (66%) presented either with uncontrolled or partially controlled asthma. This study is registered at ClinicalTrials.gov with identifier number NCT02733016.

Chronic Airflow Obstruction in a Black African Population: Results of BOLD Study, Ile-Ife, Nigeria

Global estimates suggest that Chronic Obstructive Pulmonary Disease (COPD) is emerging as a leading cause of death in developing countries but there are few spirometry-based general population data on its prevalence and risk factors in sub-Saharan Africa. We used the Burden of Obstructive Lung Disease (BOLD) protocol to select a representative sample of adults aged 40 years and above in Ile-Ife, Nigeria. All the participants underwent spirometry and provided information on smoking history, biomass and occupational exposures as well as diagnosed respiratory diseases and symptoms. Chronic Airflow Obstruction (CAO) was defined as the ratio of post-bronchodilator (BD) one second Forced Expiratory Volume (FEV1) to Forced Vital Capacity (FVC) below the lower limit of normal (LLN) of the population distribution for FEV1/FVC. The overall prevalence of obstruction (post-BD FEV1/FVC < LLN) was 7.7% (2.7% above LLN) using Global Lung Function Initiative (GLI) equations. It was associated with few respiratory symptoms; 0.3% reported a previous doctor-diagnosed chronic bronchitis, emphysema or COPD. Independent predictors included a lack of education (OR 2.5, 95% CI: 1.0, 6.4) and a diagnosis of either TB (OR 23.4, 95% CI: 2.0, 278.6) or asthma (OR 35.4, 95%CI: 4.9, 255.8). There was no association with the use of firewood or coal for cooking or heating. The vast majority of this population (89%) are never smokers. We conclude that the prevalence of CAO is low in Ile-Ife, Nigeria and unrelated to biomass exposure. The key independent predictors are poor education, and previous diagnosis of tuberculosis or asthma.

Different Severity and Severity Predictors in Early-Onset and Late-Onset Asthma: A Taiwanese Population-Based Study

BACKGROUND

Late-onset asthma has been shown to be more severe than early-onset asthma in clinic-based studies. However, population-based studies are scarce, and the predictors of severity have been less studied.

OBJECTIVES

To determine asthma severity and severity predictors regarding age at onset.

METHODS

A cross-sectional questionnaire survey was conducted among parents of children from 94 schools in Taiwan in 2004. Asthma severity was defined as short-acting β2-agonist (SABA), inhaled corticosteroid (ICS) and health care use in the last year. Information on age at onset, demographics, heredity and home exposure was collected. Ordered logistic or logistic regression was used for determining the associations between risk factors and severity.

RESULTS

Participants aged 26-50 years were included, resulting in 21,057 (67.8%) participants. Among them, 449 reported ever having had physician-diagnosed asthma, and 381 of those subjects answered the question on age at asthma onset. The risks of rescue SABA, ICS and health care use were generally higher among late-onset (13-50 years) than early-onset (0-12 years) asthmatics. Use of SABA and health care increased from childhood-onset, adolescent- or young adult-onset to adult-onset asthma. Allergic rhinitis was positively associated with SABA use (OR, 9.08; 95% CI, 1.06-77.99) and ICS use (OR, 5.08; 95% CI, 1.47-17.52) in early-onset asthma. Dehumidifier use was negatively associated with SABA use (OR, 0.50; 95% CI, 0.29-0.87) and ICS use (OR, 0.38; 95% CI, 0.19-0.78) in late-onset asthma.

CONCLUSIONS

In adults, late-onset asthma was more severe than early-onset asthma. Severity, as indicated by SABA and ICS use, was positively associated with allergic rhinitis in early-onset asthma and negatively associated with dehumidifier use in late-onset asthma.

Prognosis of new-onset asthma diagnosed at adult age

BACKGROUND

Asthma is a common chronic disease, which can affect patients at any age. Recently, cluster analyses have suggested that patients with asthma can be divided into different phenotypes and that the age at the onset of the disease is a critical defining factor. The prognosis of allergic childhood-onset asthma is relatively well known, whereas the prognosis of adult-onset asthma remains unclear.

METHODS

We undertook a systematic review to identify studies that evaluated the long-term prognosis of new-onset asthma diagnosed at adult age. Criteria used (set 1) were: 1. adult-onset asthma, 2. physician diagnosed asthma (including objective lung-functions) < 1 year before the first visit, 3. follow-up time of at least 5 years, 4. objective lung function measurements used at follow-up and 5. not a comparative trial. Another set of studies (set 2) with less strict criteria were gathered.

RESULTS

The main result of this systematic review is that the amount of evidence on the prognosis of new-onset asthma diagnosed at adult age is very limited. Only one study (n = 250) fulfilled the criteria (set 1) and it suggests that the five-year prognosis of new-onset asthma diagnosed at adult age may not be favorable, the proportion of patients being in remission was less than 5%. Furthermore, six additional follow-up studies (n = 964) were identified including mainly patients with adult-onset asthma (set 2). These studies had variable endpoints and the results could not be combined.

CONCLUSION

Further follow-up studies that recruit patients with new-onset adult asthma are needed to understand the prognostic factors in adult-onset asthma.

Vitamin D reduces eosinophilic airway inflammation in nonatopic asthma

BACKGROUND

Low levels of vitamin D are associated with asthma severity, airway remodeling, and exacerbation rate increase, especially in nonatopic asthma. Reduced steroid responsiveness or impaired antimicrobial defense might be underlying mechanisms.

OBJECTIVE

We sought to evaluate the effect of vitamin D supplementation on eosinophilic and neutrophilic airway inflammation in patients with nonatopic asthma.

METHODS

In a double-blind, randomized, placebo-controlled trial, we investigated the effect of long-acting vitamin D3 (400,000 IU) on sputum neutrophils and eosinophils in 44 patients with nonatopic asthma with neutrophilic (≥53%) and/or eosinophilic (≥3%) airway inflammation. Sputum induction was performed at baseline and after 9 weeks. Other measurements included questionnaires, blood samples, and pulmonary function.

RESULTS

Treatment with vitamin D did not significantly affect sputum neutrophils or eosinophils compared with treatment with placebo in the total group. Regarding sputum eosinophils, the effect of vitamin D appeared to be dependent on baseline sputum eosinophil levels (interaction P = .015). In patients with eosinophil levels of 26.2% or more (median in patients with sputum eosinophilia, >3%), eosinophils decreased from a median of 41.0% to 11.8% after vitamin D treatment as compared with an increase from 51.8% to 63.3% in patients receiving placebo (P = .034). Vitamin D treatment also resulted in slightly better Asthma Control Questionnaire scores (P = .08).

CONCLUSIONS

Vitamin D supplementation reduced eosinophilic airway inflammation in patients with nonatopic asthma with severe eosinophilic airway inflammation, but did not affect sputum neutrophils. Also, a small effect on asthma control was observed. These findings suggest that vitamin D might have potential as an add-on treatment option in eosinophilic asthma.

Sputum eosinophilia is a determinant of FEV1 decline in occupational asthma: results of an observational study

OBJECTIVE

To evaluate the potential determinants of forced expiratory volume in 1 s (FEV1) decline in workers with occupational asthma (OA) still exposed to the causative agent. We hypothesised that sputum eosinophilia might be a predictor of poor asthma outcome after diagnosis.

SETTING, DESIGN AND PARTICIPANTS

In a specialistic clinical centre of the University Hospital of Pisa, we studied 39 participants (28 M, 11 F) diagnosed as having OA, routinely followed up between 1990 and 2009. They were a subgroup of 94 participants diagnosed as affected by OA in that period: 9 had been removed from work at the diagnosis, 21 were excluded for having ceased occupational exposure after few months from diagnosis, and 25 were lost at the follow-up or had no acceptable sputum measurements at the diagnosis. Estimates of the decline in FEV1 were obtained by means of simple regression analysis during the period of occupational exposure after diagnosis. Logistic regression was used to analyse the effects of factors (baseline FEV1 and sputum inflammatory cells, duration and type of exposure) that may potentially influence FEV1 decline.

RESULTS

At follow-up (5.7+3.7 years), most participants were still symptomatic despite inhaled corticosteroids (ICS) treatment and had their occupational exposure reduced. Participants with higher sputum eosinophils (>3%) at baseline had a significantly greater decline of FEV1 (-52.5 vs -18.6 mL/year, p=0.012). Logistic regression showed that persistent exposure and sputum eosinophilia were significantly associated with a greater decline in FEV1 (OR 11.5, 95% CI 1.8 to 71.4, p=0.009 and OR 6.7, 95% CI 1.1 to 41.7, p= 0.042, respectively).

CONCLUSIONS

Sputum eosinophilia at diagnosis, together with the persistence of occupational exposure during follow-up, may contribute to a greater decline in FEV1 in patients with OA still at work. Further long-term studies are required as to whether intensive ICS treatment may be beneficial for patients with OA and increase ad eosinophilic inflammation.

Persistent severe hypereosinophilic asthma is not associated with airway remodeling

Hypereosinophilic asthma (HEA) is considered as a specific severe asthma phenotype. Whether eosinophils have a link with airway remodeling characterized by pathological (thickening of the basement membrane), functional (persistent airflow impairment and decline in lung function) and imaging features (increase airway wall thickness at CT scan) is still debated. In a one year prospective cohort of 142 severe asthma patients (according to IMI), 14 persistent HEA patients (defined by a persistent blood eosinophilia >500/mm(3) at two consecutive visits) were identified and compared with ten patients without any blood eosinophilia during the follow-up period (NEA, blood eosinophilia always <500/mm(3)). Airflow and lung volumes were recorded. Bronchial biopsies obtained at enrollment were stained for eosinophils (EG2) and basement membrane thickness (BM) was quantified. Imaging by CT scan acquisition was standardized and bronchial abnormalities quantified. ACQ score and exacerbations were prospectively recorded. HEA was not associated with preeminent features of airway remodeling assessed by airflow impairment (Best ever FEV1 values 97% ± 20 in HEA vs. 80 ± 24% in NEA, p = 0.020), decline of FEV1 (FEV1 Decline 40 ± 235 ml/y in HEA vs. 19 ± 40 ml/y in NEA, P = 0.319), submucosal abnormalities (BM thickness 7.80 ± 2.66 μm in HEA vs. 6.84 ± 2.59 in NEA, p = 0.37) and airway wall thickening at CT-scan (0.250 ± 0.036 mm vs. 0.261 ± 0.043, p = 0.92). Eosinophils blood count was inversely correlated with semiquantitative imaging score (rho -0.373, p = 0.039). Smoking history and positive skin prick tests were independent risk factors for increased BM thickening. Outcomes were similar in both populations (Control and exacerbations). Persistent HEA is not associated with evidences of airway remodeling.

The longitudinal relationship of changes of adiposity to changes in pulmonary function and risk of asthma in a general adult population

BACKGROUND

Adiposity has been linked to both higher risk of asthma and reduced lung function. The effects of adiposity on asthma may depend on both atopic status and gender, while the relationship is less clear with respect to lung function. This study aimed to explore longitudinal weight changes to changes in forced expiratory volume in first second (FEV1) and forced vital capacity (FVC), as well as to incident cases of asthma and wheezing, according to atopy and gender.

METHODS

A general population sample aged 19-72 years was examined with the same methodology five years apart. Longitudinal changes in weight, body mass index, waist circumference, and fat percentage (bio-impedance) were analyzed with respect to changes of FEV1 and FVC (spirometry), and incidence of asthma and wheezing (questionnaire). Gender, atopy (serum specific IgE-positivity to inhalant allergens) and adipose tissue mass prior to adiposity changes were examined as potential effect modifiers.

RESULTS

A total of 2,308 persons participated in both baseline and five-year follow-up examinations. Over the entire span of adiposity changes, adiposity gain was associated with decreasing levels of lung function, whereas adiposity loss was associated with increasing levels of lung function. All associations were dependent on gender (p-interactions < 0.0001). For one standard deviation weight gain or weight loss, FEV1 changed with (+/-)72 ml (66-78 ml) and FVC with (+/-)103 ml (94-112 ml) in males. In females FEV1 changed with (+/-) 27 ml (22-32 ml) and FVC with (+/-) 36 ml (28-44 ml). There were no changes in the FEV1/FVC-ratio. The effect of adiposity changes increased with the level of adipose tissue mass at the start of the study (baseline), thus, indicating an aggregate effect of the total adipose tissue mass. Atopy did not modify these associations. There were no statistically significant associations between changes in adiposity measures and risk of incident asthma or wheeze.

CONCLUSIONS

Over a five-year period, increasing adiposity was associated with decreasing lung function, whereas decreasing adiposity was associated with increasing lung function. This effect was significantly greater in males than in females and increased with pre-existing adiposity, but was independent of atopy.

The relation of airway obstruction to asthma, chronic rhinosinusitis and age: results from a population survey of adults

RATIONALE

There is conflicting evidence on whether patients with asthma experience an accelerated decline in lung function with age. We examined the association between postbronchodilator lung function, asthma, chronic rhinosinusitis (CRS), and atopy with age using a large European sample.

METHODS

In 17 centers in 11 European countries, case-control studies were nested within representative cross-sectional surveys of adults aged less than 75 years. Representative samples of participants with asthma, CRS or both and controls were assessed for postbronchodilator ventilatory function, smoking history, atopy, and treatment. Multiple regression was used to assess the interactive effects of age and diagnostic group on decline in postbronchodilator ventilatory function.

RESULTS

A total of 3337 participants provided adequate data (778 with asthma, 399 with CRS, 244 with both asthma and CRS and 1916 controls who had neither asthma nor CRS). Participants with asthma had lower FEV1 /FVC (-4.09% (95% CI: -5.02, -3.15, P < 0.001) and a steeper slope of FEV1 /FVC against age (-0.14%/annum [95%CI: -0.19, -0.08]) equivalent to smoking 1-2 packs of cigarettes per day. Those with atopy had a slope equivalent to controls.

CONCLUSIONS

People with asthma have a steeper decline in postbronchodilator lung function with age, but neither CRS nor atopy alone were associated with such decline.

Chronic obstructive pulmonary disease in non-smokers: a case-comparison study

BACKGROUND

COPD is often regarded as a smoker's disease. In fact, up to 50% of COPD could be attributable to other causes. Relatively little is known about COPD among nonsmokers, and this group is usually excluded from studies of COPD.

METHODS

In this cross-sectional case-comparison study, smokers and nonsmokers aged over 45 with COPD (post-bronchodilator FEV1 ≤ 70% predicted, FEV1/FVC ratio < 0.7) were recruited from specialist outpatient clinics and from primary care. Subjects completed a questionnaire and interview, and underwent spirometry, venesection, exhaled nitric oxide (ENO) measurement, allergen skinprick testing, formal lung function testing and high resolution CT.

RESULTS

48 nonsmokers and 45 smokers participated. Asthma was nearly universal among nonsmokers and was the commonest identifiable cause of COPD in that group. Nonsmokers also exhibited a high prevalence of objective eosinophilic inflammation (raised ENO and eosinophil counts, positive skinprick tests). Smokers had more severe airflow obstruction, but respiratory symptom prevalences were similar between groups. Nonsmokers reported greater lifetime burdens of respiratory disease. Nonsmokers' HRCT results showed functional small airways disease, with no significant emphysema in any subject. Previously undiagnosed bronchiectasis was common in both groups (31% and 42%).

CONCLUSIONS

Asthma is a very common cause of COPD among nonsmokers. Radiological bronchiectasis is common in COPD; the clinical significance of this finding is unclear.

Severe adult-onset asthma: A distinct phenotype

BACKGROUND

Some patients with adult-onset asthma have severe disease, whereas others have mild transient disease. It is currently unknown whether patients with severe adult-onset asthma represent a distinct clinical phenotype.

OBJECTIVE

We sought to investigate whether disease severity in patients with adult-onset asthma is associated with specific phenotypic characteristics.

METHODS

One hundred seventy-six patients with adult-onset asthma were recruited from 1 academic and 3 nonacademic outpatient clinics. Severe refractory asthma was defined according to international Innovative Medicines Initiative criteria, and mild-to-moderate persistent asthma was defined according to Global Initiative for Asthma criteria. Patients were characterized with respect to clinical, functional, and inflammatory parameters. Unpaired t tests and χ(2) tests were used for group comparisons; both univariate and multivariate logistic regression were used to determine factors associated with disease severity.

RESULTS

Apart from the expected high symptom scores, poor quality of life, need for high-intensity treatment, low lung function, and high exacerbation rate, patients with severe adult-onset asthma were more often nonatopic (52% vs 34%, P = .02) and had more nasal symptoms and nasal polyposis (54% vs 27%, P ≤ .001), higher exhaled nitric oxide levels (38 vs 27 ppb, P = .02) and blood neutrophil counts (5.3 vs 4.0 10(9)/L, P ≤ .001) and sputum eosinophilia (11.8% vs 0.8%, P ≤ .001). Multiple logistic regression analysis showed that increased blood neutrophil (odds ratio, 10.9; P = .002) and sputum eosinophil (odds ratio, 1.5; P = .005) counts were independently associated with severe adult-onset disease.

CONCLUSION

The majority of patients with severe adult-onset asthma are nonatopic and have persistent eosinophilic airway inflammation. This suggests that severe adult-onset asthma has a distinct underlying mechanism compared with milder disease.

Increased periostin associates with greater airflow limitation in patients receiving inhaled corticosteroids

BACKGROUND

Periostin, an extracellular matrix protein, contributes to subepithelial thickening in asthmatic airways, and its serum levels reflect airway eosinophilic inflammation. However, the relationship between periostin and the development of airflow limitation, a functional consequence of airway remodeling, remains unknown.

OBJECTIVE

We aimed to determine the relationship between serum periostin levels and pulmonary function decline in asthmatic patients on inhaled corticosteroid (ICS) treatment.

METHODS

Two hundred twenty-four asthmatic patients (average age, 62.3 years) treated with ICS for at least 4 years were enrolled. Annual changes in FEV1, from at least 1 year after the initiation of ICS treatment to the time of enrollment or later (average, 16.2 measurements over 8 years per individual), were assessed. At enrollment, clinical indices, biomarkers that included serum periostin, and periostin gene polymorphisms were examined. Associations between clinical indices or biomarkers and a decline in FEV1 of 30 mL or greater per year were analyzed.

RESULTS

High serum periostin levels (≥ 95 ng/mL) at enrollment, the highest treatment step, higher ICS daily doses, a history of admission due to asthma exacerbation, comorbid or a history of sinusitis, and ex-smoking were associated with a decline in FEV1 of 30 mL or greater per year. Multivariate analysis showed that high serum periostin, the highest treatment step, and ex-smoking were independent risk factors for the decline. Polymorphisms of periostin gene were related to higher serum periostin levels (rs3829365) and a decline in FEV1 of 30 mL or greater per year (rs9603226).

CONCLUSIONS

Serum periostin appears to be a useful biomarker for the development of airflow limitation in asthmatic patients on ICS.

Fixed airflow obstruction among nonsmokers with asthma:a case-comparison study

BACKGROUND

Airflow obstruction in asthma is usually reversible, but fixed obstruction develops in some individuals. Little is known about risk factors for development of fixed airflow obstruction in nonsmokers with asthma.

METHODS

This case-comparison study recruited nonsmokers aged over 45 years with physician-diagnosed asthma from specialist outpatient clinics and primary care. Two age-matched groups were recruited on the basis of spirometry: anobstructed group (post-bronchodilator FEV(1) ≤ 70% predicted, FEV1/FVC ratio < lower limit of normal) and a control group with normal lung function. Subjects completed a questionnaire and interview, and underwent spirometry, venesection, exhaled nitric oxide (ENO) measurement, allergen skinprick testing, and formal lung function testing.

RESULTS

Thirty-four obstructed subjects and 40 controls participated in the study. Obstructed subjects exhibited greater evidence of systemic inflammation, abnormal glucose homeostasis, and central obesity than controls. Obstructed subjects reported longer duration of asthma, and childhood respiratory infection was commoner in that group. Metabolic syndrome prevalence was similar between groups, but several features of insulin resistance were associated with reduced FEV(1). Cough and sputum were common among controls.

CONCLUSIONS

Risk of fixed airflow obstruction may correlate with lifetime asthma duration. Individuals with coexisting asthma and fixed airflow obstruction have heightened systemic inflammation. A variety of chronic respiratory symptoms are common among "healthy" nonsmokers with asthma.

Sensitization to pets is a major determinant of persistent asthma and new asthma onset in Sweden

INTRODUCTION

Our knowledge about atopy as a longitudinal predictor of asthma is limited. The purpose of this study was to investigate the prognosis of asthma and risk factors for asthma onset, especially sensitization of specific allergens in a population sample.

MATERIAL AND METHODS

A cohort responded to a respiratory questionnaire in 1990 and 2003. At baseline, 2,060 subjects who, in the screening questionnaire, reported respiratory symptoms and 482 controls were investigated with interviews, spirometry, and skin-prick test. A total of 721 asthmatics and 976 subjects without respiratory disease were clinically verified. At follow-up in 2003, 340 subjects with persistent asthma and 186 subjects with asthma remission were identified, while 76 subjects reported new asthma onset.

RESULTS

Sensitization to pets and a high symptom score were significant determinants of persistent asthma (odds ratio (OR) 3.2 (95% CI 1.9-5.6) and 5.7 (2.5-13.3), respectively) and onset of asthma (OR 2.6 (1.1-6.0), and 1.7 (1.2-2.3)). A high self-reported responsiveness to airway irritants (OR 1.6 (1.1-2.2)), and more asthma medications (OR 2.0 (1.3-2.9)) were additional indicators of persistent asthma at the follow-up. Belonging to the older age group decreased the risk both of having persistent asthma and asthma onset.

DISCUSSION

Asthmatics sensitized to pets have a more severe outcome than asthmatics not sensitized to pets. Sensitization to pets was also a strong predictor for onset of asthma. Special attention should be given to asthmatics who report having severe symptoms and problems with airway irritants as such patients are more likely to have persistent problems.

Non-atopic males with adult onset asthma are at risk of persistent airflow limitation

BACKGROUND

Patients with asthma have on average a more rapid decline in FEV (1) as compared with the general population. Recent cluster analysis has revealed different asthma phenotypes that can be distinguished by age of onset and reversibility of airflow limitation.

OBJECTIVE

This study aimed at detecting risk factors associated with persistent airflow limitation in patients with the adult onset asthma phenotype.

METHODS

We recruited 88 patients with adult onset (≥ 18 years) asthma from an academic pulmonary outpatient clinic in the Netherlands. The associations of age, age of asthma onset, asthma duration, gender, race, atopy, smoking pack-years, BMI, use of oral corticosteroids with post-bronchodilator FEV (1) /FVC were investigated.

RESULTS

Multiple linear regression analysis showed an association of absence of atopy (r = -0.27, B = -0.26, P = 0.01) and male gender (r = 0.31, B = 0.30, P = 0.004) with post-bronchodilator FEV (1) /FVC. Multiple logistic regression analysis showed that male patients were 10.8 (CI: 2.6-45.2) times the odds than women to have an FEV (1) /FVC < 0.7, and non-atopic patients were 5.2 (CI: 1.3-20.3) times the odds to have an FEV (1) /FVC < 0.7 than atopic patients.

CONCLUSIONS AND CLINICAL RELEVANCE

We conclude that in patients with adult onset asthma, male gender and absence of atopy are associated with persistent airflow limitation. This might suggest that amongst patients with adult onset asthma, non-atopic male patients are at increased risk of accelerated decline in lung function.

Smoking and asthma: disentangling their mutual influences using a longitudinal approach

BACKGROUND

The association between smoking and asthma remains unclear and has mostly been assessed in cross-sectional studies, with potential selection bias ("healthy smoker effect").

AIMS

Using a longitudinal approach, the aims were to assess whether 1) childhood asthma modifies smoking initiation, 2) active smoking influences asthma incidence in adults and 3) active smoking among subjects with asthma influences the persistence of the disease or the 12-year evolution in lung function in children and adults.

METHODS

Subjects (513 children and 1190 adults) were recruited and followed-up for 12 years in the context of the EGEA study (Epidemiological study on the Genetics and Environment of Asthma).

RESULTS

Childhood asthma was not associated with a decreased probability of starting active smoking (Hazard Ratio, HR = 0.96; 95% confidence interval (CI): 0.72, 1.27). Smoking at baseline was associated with a higher risk for asthma incidence in adulthood (HR = 1.95, 95% CI: 1.00, 3.77). Among subjects with asthma, smoking was unrelated to lung function evolution; however, among children with moderate to severe asthma at inclusion, smoking tended to slow down the lung function growth (P = 0.04).

CONCLUSION

These findings support the hypothesis that childhood asthma does not prevent smoking initiation and confirm that active smoking has a deleterious role on asthma. Altogether this study emphasizes the importance of active smoking as a serious public health problem particularly for children and women.

sICAM-1 and TNF-α in asthma and rhinitis: relationship with the presence of atopy

BACKGROUND

A genetically determined overproduction of specific immunoglobulin E (IgE) underlies many diseases like asthma or allergic rhinitis. IgE as well as tumor necrosis factor-α (TNF-α), and intercellular adhesion molecule-1 (ICAM-1) play a critical role in the induction and maintenance of inflammation. While the correlation between IgE and atopy is inseparable, little is known about the correlation of atopy with markers of inflammation.

OBJECTIVE

We investigated the relationship between the serum concentrations of TNF-α, soluble ICAM-1 (sICAM-1), and the presence of atopy in patients with persistent rhinitis or asthma.

METHODS

Serum concentrations of sICAM-1, TNF-α, and total IgE were investigated in 64 adults with persistent allergic rhinitis, 17 subjects with nonatopic rhinitis, 90 patients with asthma, and 21 healthy individuals. Atopy was diagnosed on the basis of positive family history, skin prick tests, and serum IgE concentration.

RESULTS

Total IgE concentration was significantly higher in patients with atopic rhinitis or asthma when compared with nonatopic patients and healthy individuals and was the highest in patients suffering from severe atopic asthma who were not treated with systemic glucocorticosteroids. Although there were marked alterations in IgE in atopic and nonatopic patients, there were no significant differences between atopic and corresponding groups of nonatopic rhinitic and asthmatic patients in sICAM-1 and TNF-α concentrations. (sICAM-1 in rhinitis: atopic vs. nonatopic patients: 224.02 and 221.08 ng/ml, respectively, p > .05; in mild/moderate asthma: atopic vs. nonatopic: 306.22 and 326.39 ng/ml, respectively, p > .05; severe asthma without oral corticosteroids therapy: atopic vs. nonatopic: 418.03 and 468.09 ng/ml, respectively, p > .05; and severe asthma with oral corticosteroids therapy: atopic vs. nonatopic: 320.66 and 308.09 ng/ml, respectively, p > .05).

CONCLUSIONS

Concentrations of sICAM-1 and TNF-α are significantly higher in patients with asthma compared with those observed in patients with rhinitis, but they are independent of the presence of atopy.

Smoking and nonsmoking asthma: differences in clinical outcome and pathogenesis

Cigarette smoking in asthma is frequently present and is associated with worsening of symptoms, accelerated lung-function decline, a higher frequency of hospital admissions, a higher degree of asthma severity, poorer asthma control and reduced responsiveness to corticosteroids. Furthermore, it is associated with reduced numbers of eosinophils and higher numbers of mast cells in the submucosa of the airway wall. Airway remodeling is increased as evidenced by increased epithelial thickness and goblet cell hyperplasia in smoking asthmatics. The pathogenesis responsible for smoking-induced changes in airway inflammation and remodeling in asthma is complex and largely unknown. The underlying mechanism of reduced corticosteroid responsiveness is also unknown. This article discusses differences between smoking and nonsmoking asthmatics regarding the clinical expression of asthma, lung function, response to corticosteroids, airway inflammation and remodeling processes. Possible pathogenetic mechanisms that may explain the links between cigarette smoking and changes in the clinical expression of asthma will be discussed, as well as the beneficial effects of smoking cessation.

The persistence of allergen exposure favors pulmonary function decline in workers with allergic occupational asthma

BACKGROUND

In asthmatics, a rapid decline in pulmonary function is observed, likely as a consequence of airways remodeling. Persistence of allergen exposure in patients with occupational asthma (OA) maintains chronic bronchial inflammation, resulting in a more severe lung function decline. Few studies were performed on the effects of allergen exposure cessation.

OBJECTIVE

This study aims at evaluating the influence of allergen exposure cessation on respiratory decline in allergic asthmatic workers.

METHODS

Two groups of workers with allergic OA were selected. The first group (30 workers) changed job after the diagnosis and was no more exposed to sensitizing allergens, and the second group (28 subjects) did not and, as a consequence of preventive measures in the work place, was exposed to a lower level of allergens. All were treated with conventional therapy, according to GINA protocols. FEV1 changes during a 12-year period were evaluated.

RESULTS

Despite pharmacological therapy, the pulmonary function decay slope was steeper in workers continuously exposed to the sensitizing agent (even at reduced level) than in those with a complete cessation of exposure: final FEV1 loss was 512.5 ± 180 ml versus 332.5 ± 108 ml, respectively. The difference became significant after 4 years from the cessation of the exposure.

CONCLUSIONS

The study shows that the cessation of the exposure to allergen in the work place appears the most effective measure in limiting pulmonary function decline in asthmatic workers and underlines the importance of allergic risk assessment and control in the management of occupational asthma.

Airway eosinophilia in remission and progression of asthma: accumulation with a fast decline of FEV(1)

BACKGROUND

As it is unknown whether complete asthma remission or progression of asthma is associated with airway inflammation and remodeling, we assessed these characteristics in bronchial biopsies of relevant subsets of asthma patients.

METHODS

Sputum and bronchial biopsies were obtained from asthma patients in remission (PC(20) histamine> 32 mg/ml, PC(20) AMP> 320 mg/ml) and from those with either a slow FEV(1) decline (< 30 ml/year) or fast decline (> 30 ml/year). Inflammatory cells and mediators were determined in sputum, inflammatory cells and aspects of airway remodeling in bronchial biopsies.

RESULTS

Asthmatics in remission and asthma patients with a slow FEV(1) decline had a similar extent of airway inflammation and remodeling in sputum and bronchial biopsies. Asthma patients with a fast FEV(1) decline had high sputum eosinophil numbers. Moreover, FEV(1) decline (ml/year) correlated with sputum eosinophil numbers (Rs=0.51, p=0.003) and ECP levels (Rs=0.57, p=0.001). Airway remodeling, i.e. basement membrane thickness, correlated with sputum eosinophils (Rs=0.69, p<0.001), sputum ECP (Rs=0.46, p=0.018) and airway wall eosinophil numbers (Rs=0.49, p=0.002).

CONCLUSIONS

Asthma, even when in remission, is accompanied by airway inflammation and remodeling. Data suggest that eosinophils are important in a subset of asthma patients by association to accelerated FEV(1) decline and change of basement membrane thickness.

Annual change of respiratory functions in adult patients with asthma: the potential of antiasthma treatments for many years to repair irreversible changes of the airway

BACKGROUND

Little is known regarding annual changes of respiratory functions among patients with asthma after asthma symptoms enter remission.

OBJECTIVE

Annual changes of respiratory function and influence of patient characteristics and treatment variables on these changes were assessed in patients with adult asthma.

METHODS

Respiratory function (pre- and postbronchodilator forced expiratory volume in one second [FEV₁] and reversibility by short-acting β₂-agonist) and their changes were retrospectively investigated and relationships between these changes, after symptomatic remission, and patient characteristics and treatments were analyzed in adult outpatients with asthma who had undergone spirometry (including a reversibility test) ≥5 times in >5 years.

RESULTS

In patients ≥40 years old, or with disease duration ≥10 years or receiving treatment for severe asthma (steps 4-5, high-dose inhaled glucocorticosteroids, or addition of other medications), both pre- and postbronchodilator FEV₁ values were significantly lower (p < .05). Mean annual change of prebronchodilator FEV₁ (Δpre-FEV₁), annual change of postbronchodilator FEV₁ (Δpost-FEV₁), and annual change of reversibility (Δ reversibility) were -13.8 ± 59.7 ml/year, -25.9 ± 51.0 ml/year, and -0.56% ± 1.89%/year, respectively. Multivariate analysis after stepwise selection for variables in patient characteristics or treatments showed that disease duration ≥10 years contributed to annual improvement of respiratory functions (Δpre-FEV₁: odds ratio [OR] 1.57, 95% confidence interval [CI] 1.01-2.46; Δpost-FEV₁: OR 2.13, 95% CI 1.25-3.66), treatment with long-acting β₂-agonists (LABAs) contributed to annual improvement of respiratory function (Δpre-FEV₁: OR 2.05, 95% CI 1.23-3.16; Δpost-FEV₁: OR 1.78, 95% CI 1.11-2.87), and poor compliance contributed to annual worsening of respiratory functions (Δpre-FEV₁: OR 0.43, 95% CI 0.24-0.76; Δpost-FEV₁: OR 0.39, 95% CI 0.22-0.70). In addition, duration of disease ≥10 years and severe treatment (steps 4-5) from the beginning contributed to decreasing Δreversibility (OR 0.55, 95% CI 0.34-0.87 and OR 0.50, 95% CI 0.29-0.83, respectively).

CONCLUSIONS

Long-term treatments for asthma are expected to normalize respiratory dysfunction, which cannot be repaired in the short term. Treatment with LABAs and patient compliance may be the most important factors associated with annual improvement of respiratory functions.

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

RATIONALE

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

OBJECTIVES

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

METHODS

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

MEASUREMENTS AND MAIN RESULTS

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

CONCLUSIONS

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

The importance of airway remodelling in the natural course of asthma

INTRODUCTION

Asthma is associated with airflow limitation and increased decline in lung function. The underlying mechanism for this was probably that persisting inflammation leads to remodelling of the airways.

OBJECTIVES

To review the importance of different factors which are related to airflow limitation and lung function decline in asthma.

METHODS

Case report and literature review.

RESULTS

Asthma severity, smoking, bronchial hyperresponsiveness and eosinophil inflammation were the variables that were most convincingly related to decline in forced expiratory volume in 1 s (FEV(1)) in asthma. Treatment with inhaled corticosteroids probably decreased the rate of FEV(1) decline, although this was more uncertain because of the lack of randomised double blind studies that show such an effect. Progress in the field of the genetics of asthma may, in the near future, elucidate the role of gene-environment interaction in lung function decline in asthma.

CONCLUSION

Regular treatment with inhaled corticosteroids may partly have a beneficial effect on airway remodelling in asthma. Improved understanding of the processes leading to airway remodelling is, however, important in order to prevent a large number of asthmatics from developing irreversible airflow obstruction.

Relative and additional bronchodilator response of salbutamol and ipratropium in smoker and nonsmoker asthmatics

PURPOSE

This study was conducted in the Department of Tuberculosis and Respiratory Diseases, J. N. Medical College, Aligarh, India, from January 2006 to December 2007. The fact that smoker asthmatics can behave like chronic obstructive pulmonary disease (COPD) patients encourages the researcher to therapeutically exploit the important cholinergic influence in these patients. To clarify the clinical importance of the issue, the present nonblind and nonrandomized study was aimed at relative bronchodilator response to adrenergic and cholinergic agents.

METHODS

Ninety-six patients of asthma, 48 nonsmokers and 48 smokers, were given sequential doses of inhaled salbutamol and after achieving maximum bronchodilation, ipratropium was administered to observe the additional bronchodilation. On the next day, the sequence of drugs was reversed. Ipratropium was given first and after achieving maximal response, salbutamol was given.

RESULTS

On giving salbutamol first, maximal improvement in forced expiratory volume in one second (FEV(1)) was 67.04% +/- 12.98% in nonsmokers and 60.64% +/- 13.6% in smokers. The additional improvement with ipratropium was 9.22% +/- 2.08% in smokers and was significantly higher (p <.001) than in nonsmokers (0.13% +/- 2.14%). When ipratropium was given first, maximum improvement in FEV(1) was 41.95% +/- 4.57% in smokers, which was significantly higher (p <.001) than in nonsmokers (20.06% +/- 7.06%). The additional improvement with salbutamol was 23.16% +/- 5.07% and 19.09% +/- 4.9%, respectively, in nonsmokers and smokers.

CONCLUSIONS

With the above results, the authors concluded that in smoker asthmatics, cholinergic tone was more prominent and there was down-regulation of adrenergic receptors, as both drugs caused significant additional dilatation. So in smoker asthmatics, addition of a cholinergic agent will result in better control of asthma. In nonsmoker asthmatics, addition of cholinergic agent is of little or no value.

Clinical efficacy of house dust mite-specific immunotherapy in asthmatic children

BACKGROUND

Immunotherapy has been widely used in the treatment of allergic diseases. We evaluated the clinical efficacy of specific immunotherapy with extracts of Dermatophagoides pteronyssinus (Dp) and Dermatophagoides farinae (Df) in children with asthma.

METHODS

All 40 children had moderate-to-severe asthma and positive allergen tests for Dp and Df. All required daily medication. They were randomly assigned to two groups: Half of them received immunotherapy with subcutaneous injections of Dp and Df extracts, while the other half were not given immunotherapy. Participants were followed up for more than 6 months.

RESULTS

Children in both groups had apparent improvements in medication use and symptoms after 6 months. The mean medication scores declined from 3.6 +/- 1.14 to 1.7 +/- 0.66 in the immunotherapy group (p < 0.01) and from 3.35 +/- 0.87 to 2.4 +/- 1.09 in the control group (p < 0.01). There was a significant difference between the two groups (mean difference 0.95; p < 0.01). The symptom score improved in the immunotherapy group from 2.65 +/- 0.98 to 1.20 +/- 1.00 (p < 0.01) and in the control group from 2.55 +/- 0.99 to 1.40 +/- 0.88 (p < 0.01), with a significant difference between the two groups (mean difference 0.3; p < 0.01). The number of office visits in the immunotherapy group was greater than that of the controls, but the frequencies of emergency room visits and hospitalization decreased.

CONCLUSION

Our study showed that specific immunotherapy with Dp and Df was beneficial for asthmatic children.

Long-term prognosis of asthma is good--a 12-year follow-up study. Influence of treatment

The number of studies on the prognosis of bronchial asthma (BA) is rather limited. The aim of the study was to determine the evolution of BA in a long-term 12-year follow-up and to investigate possible contributing factors. One hundred and sixty-three patients who visited the Out-patient Clinic for BA from 1989 to 1993 (Visit 1) were included in the study. They were re-evaluated during 2003-2005 (Visit 2). At both visits, the patients filled in a special questionnaire, underwent skin tests, spirometry, methacholine challenge and they were classified into three severity groups according to GINA of 1992 as: Mild, Moderate, and Severe asthma. At Visit 1, 95 (58.3%) patients were classified in the mild asthma group, 45 (27.6%) in moderate and 23 (14.1%) in severe; whereas at Visit 2, 107 (65.6%) patients had mild asthma, 44 (27%) moderate and 12 (7.4%) severe. At Visit 1 asthma severity was associated with male gender, younger age, and the absence of rhinitis. At Visit 2 on the other hand, asthma severity was associated with older age, longer duration of disease, smoking and again the absence of rhinitis and increased BHR at both visits. Inhaled corticosteroid use correlated with improvement in lung function. Long-term prognosis of BA was good and outcome was favorably influenced by male gender, early and mild onset of disease, absence of smoking and presence of rhinitis.

Body mass index, weight gain, and other determinants of lung function decline in adult asthma

BACKGROUND

Little is known about factors associated with lung function decline in asthma.

OBJECTIVE

To identify the determinants of FEV(1) decline in adults with asthma with and without airflow obstruction at baseline.

METHODS

An international cohort of 638 subjects with asthma (20-44 years old) was identified in the European Community Respiratory Health Survey (1991-1993) and followed up from 1998 to 2002. Spirometry was performed on both occasions. FEV(1) decline was related to potential determinants evaluated at baseline and during the follow-up by random intercept linear regression models. The analyses were stratified by the presence of airflow obstruction (FEV(1)/forced vital capacity < 0.70) at baseline.

RESULTS

In the group of individuals without airflow obstruction (n = 544), a faster FEV(1) decline was observed for subjects with intermediate body mass index (BMI) than for lean and obese subjects. FEV(1) decline was associated with weight gain independently of baseline BMI, and this association was stronger in men (20; 95% CI, 10-30, mL/y/kg gained) than in women (6; 95% CI, 1-11, mL/y). In the group of individuals with airflow obstruction (n = 94), the absence of allergen sensitization and a low BMI at baseline were associated with a faster FEV(1) decline, whereas weight gain was not associated with decline.

CONCLUSIONS

The detrimental effect of weight gain on FEV(1) decline is particularly relevant in subjects with asthma who still do not have an established airflow obstruction. Our findings support the importance of weight management in asthma and recommend weight loss in overweight or obese individuals with asthma.

A population-based clinical study of allergic and non-allergic asthma

BACKGROUND

The aim of this study was to describe differences between allergic and non-allergic asthma in a large community-based sample of Danish adolescents and adults.

METHODS

A total of 1,186 subjects, 14 to 44 years of age, who in a screening questionnaire had reported a history of airway symptoms suggestive of asthma and/or allergy, or who were taking any medication for these conditions were clinically examined. All participants were interviewed about respiratory symptoms, and furthermore skin test reactivity, lung function, and airway responsiveness were measured.

RESULTS

A total of 489 individuals had clinical asthma of whom 61% had allergic asthma, whereas 39% had non-allergic asthma. Subjects with non-allergic asthma were more likely to be females, OR = 2.24 (1.32-3.72), p = 0.003, and to have cough as the predominant symptom, OR = 1.96, (1.19-3.23), p = 0.008, but were less likely to have AHR, OR = 0.40, (0.24-0.66), p < 0.001, food allergy, OR = 0.28, (0.11-0.73), p = 0.009, and symptoms of rhinitis, OR = 0.08 (0.05-0.14) compared with subjects with allergic asthma. Subjects with non-allergic asthma had had persistent symptoms within the last 4 weeks more often than subjects with allergic asthma (68% vs. 53%), p = 0.001.

CONCLUSIONS

Non-allergic asthma accounts for two in every five cases of asthma in adults and constitutes symptomatically, and in terms of lung function, a more severe form of disease than allergic asthma.

Matrix metalloproteinase-1 polymorphism is associated with persistent airway obstruction in asthma in the Taiwanese population

BACKGROUND AND OBJECTIVE

Overexpression of matrix metalloproteinase (MMP)-1 has been demonstrated in asthma, and MMP polymorphisms are known to enhance disease susceptibility. We investigated whether MMP-1 polymorphism is associated with persistent airway obstruction in asthma in the Taiwanese population.

METHODS

A total of 131 unrelated Taiwanese subjects were enrolled, age-matched, and divided as follows: (1) those who had asthma with persistent airway obstruction with forced expiratory volume in 1 second (FEV(1)) and FEV(1)/forced vital capacity (FVC) values less than 75% predicted (n = 41); (2) those with asthma without airway obstruction with FEV(1) and FEV(1)/FVC values > or = 75% predicted (n = 47); and (3) normal control subjects (n = 43). All were genotyped for the 1G/2G polymorphism of MMP-1 promoter (-1607 bp).

RESULTS

1G genotypes of MMP-1 containing at least one 1G allele were found in asthmatic patients with persistent airway obstruction (OR = 3.696, 95% CI: 1.489-9.173, p = 0.027), but not in asthmatic patients without airway obstruction (OR = 2.065, 95% CI: 0.890-4.790, p = 0.091) when compared with homozygous 2G (2G/2G). The heterozygous 1G genotype (1G/2G) was more associated with persistent airway obstruction than homozygous 2G (2G/2G) (OR: 4.727, 95% CI: 1.759-12.703, p = 0.012). The adjusted risk estimate of 1G genotypes for asthmatics with persistent airway obstruction was 4.416 (95% CI: 1.651-11.812, p = 0.003).

CONCLUSION

1G genotypes of MMP-1 polymorphism are associated with asthma with persistent airway obstruction, and the heterozygous 1G genotype (1G/2G) poses the most susceptibility to persistent airway obstruction in asthma.

Prognosis of adult asthma after normalization of bronchial hyperresponsiveness by inhaled corticosteroid therapy

BACKGROUND

Inhaled corticosteroids (ICSs) are the most effective anti-inflammatory drugs for adult asthma and can improve not only clinical symptoms but also bronchial hyperresponsiveness (BHR). However, the prognosis of adult asthma has not been well studied, and it remains to be elucidated precisely how long treatment with ICSs should be continued once clinical remission is achieved.

OBJECTIVES

We examined whether ICS use could be withdrawn or reduced without exacerbation of disease.

METHODS

We retrospectively studied 374 adult patients with asthma to determine which factors predicted the elimination or reduction of ICS treatment without exacerbations of disease after the achievement of normalized BHR to acetylcholine. The patients were classified into three groups: Group 1 had symptoms within 6 months of normalization and needed to continue therapy; group 2 received the equivalent of >or= 400 microg fluticasone propionate until BHR normalization, did not have symptoms in the 6 months after normalization, and then had their doses of ICSs halved; and group 3 received the equivalent of <or= 200 microg fluticasone propionate at an enrollment, did not have symptoms in the 6 months after normalization, and then had all ICSs withdrawn. The primary outcome measure was the presence of clinical symptoms. We used multiple logistic regression and a Kaplan-Meier analysis to analyze the factors predicting remission.

RESULTS

Twenty-nine patients in group 3 remained asymptomatic for more than 30 months (mean 47.1 +/- 12.4 months) after discontinuing ICS therapy. The predictive markers of remission were low levels of eosinophils in the sputum, high %V(50) at the first hospital visit, and the need for only a low daily dose of ICS to induce normalized BHR. Conversely, patients with severe BHR at the first hospital visit, low %FEV(1) at normalized BHR, and a need for high-dose ICSs to reach normalized BHR could not reduce or discontinue treatments.

CONCLUSION

Some adult patients with asthma whose BHR is normalized by ICS therapy can achieve remission from disease exacerbation after discontinuation of ICSs. However, patients with severe asthma or asthma of long duration may not achieve remission even if their BHR is normalized.

The association between anxiety sensitivity and atopy in adult asthmatics

There is growing evidence linking psychological stress to atopic disease, particularly asthma. Anxiety sensitivity, which is the fear of anxiety-related symptoms, may be particularly important in the study of anxiety and atopic disease. The present study examined the association between atopy and anxiety sensitivity in adult asthmatics. A total of 217 asthma patients who had undergone standard pulmonary function and allergen skin prick testing were included. Participants completed the Anxiety Sensitivity Index, Penn State Worry Questionnaire, Type D Personality Scale-16 and Beck Depression Inventory-II on the day of their asthma clinic visit. Total Anxiety Sensitivity Index score was found to be significantly higher in atopic (M = 17.15, SE = .9) versus non-atopic (M = 12.68, SE = 1.5) asthmatics, independent of age, sex, smoking status, asthma severity, asthma duration, and anxiolytic medication use (F = 6.11, p = .014). There was no evidence for a significant association between any of the other questionnaire scores and atopic status.

Association between neutrophilic airway inflammation and airflow limitation in adults with asthma

BACKGROUND

There is debate about the mechanisms of persistent airflow limitation in patients with asthma. Chronic inflammation is assumed to be important, although there is limited and contradictory information about the relationship between airway inflammation and postbronchodilator FEV1.

METHODS

We have assessed the cross-sectional relationship between prebronchodilator and postbronchodilator FEV1 and measures of airway inflammation after allowing for the effects of potential confounding factors. Multivariate analysis was performed on data collected from 1,197 consecutive patients with asthma seen at the respiratory outpatient clinic at Glenfield Hospital between 1997 and 2004. Relationships between induced sputum total neutrophil and differential eosinophil cell counts, and prebronchodilator and postbronchodilator lung function were examined.

RESULTS

Sputum total neutrophil but not differential eosinophil count was associated with lower postbronchodilator FEV1. Both differential eosinophil and total neutrophil count were associated with lower prebronchodilator FEV1. These effects were independent after adjustment for age, smoking, ethnicity, asthma duration, and inhaled corticosteroid use. A 10-fold increase in neutrophil count was associated with a 92 mL reduction (95% confidence interval, 29 to 158; p = 0.007) in postbronchodilator FEV1.

CONCLUSIONS

In this large heterogeneous population of adults with asthma, we have shown that prebronchodilator FEV1 is associated with neutrophilic and eosinophilic airway inflammation, whereas sputum total neutrophil counts alone are associated with postbronchodilator FEV1. This supports the hypothesis that neutrophilic airway inflammation has a role in the progression of persistent airflow limitation in asthma and raises the possibility that this progression and the development of COPD share a common mechanism.

Outcome and severity of adult onset asthma--report from the obstructive lung disease in northern Sweden studies (OLIN)

BACKGROUND

Studies of longitudinal changes in severity and the long-term outcome of asthma in epidemiological settings are uncommon.

AIM

To assess the outcome of incident asthma in a cohort of subjects who developed asthma after the age of 20 years.

METHODS

This is a prospective study of the outcome of 309 subjects with incident asthma being included in a case-referent study based on all adults aged 20-60 years living in three municipalities/towns in Northern Sweden. The subjects fulfilled the criteria for incident asthma defined as onset of symptoms common in asthma within 12 months prior to the study and a verified bronchial variability. In 2003, 250 (81%) of the subjects with asthma were re-examined with structured interview, lung-function test and methacholine test.

RESULTS

At follow-up, 237 (95%) subjects still had an active asthma, i.e. they had symptoms or used asthma medicines. Among those with active asthma, 65% were using inhaled cortico-steroids. Severity grading (GINA 2000) showed that 21% had mild intermittent asthma, 30% mild persistent, 44% moderate persistent, and 5% severe asthma, contrasting to 75% with moderate or severe asthma at entry. Higher age, higher BMI and low lung function were associated with greater asthma severity. Twelve subjects (5%) were in remission. Predictors for remission were non-sensitisation and a normal lung function. Age, sex, BMI, and smoking habits were not significantly different between those in remission and those not.

CONCLUSIONS

Remission of adult onset asthma was low. Severity of asthma changed considerably over time, however, the overall change was towards a milder disease probably as a result of treatment.

The natural history of asthma from childhood to adulthood

Medical Practitioners are often questioned regarding the prognosis of a child with asthma. We have performed a literature review of the natural history of childhood asthmatics. Factors which affect the natural history and prognosis of childhood asthma are discussed. Current evidence suggests that evolution of asthma severity is fairly predictable. Features of childhood asthma such as severity, duration, atopy, bronchial hyperresponsiveness and exposure to smoking can predict the course of asthma into adulthood. Most children with mild intermittent asthma will outgrow their asthma, or have mild episodic asthma. Early commencement of anti-inflammatory therapy, such as inhaled corticosteroids may prevent the progression of the disease. Most patients with mild asthma have good functional outcome and low healthcare utilisation.

Lack of association between indoor allergen sensitization and asthma morbidity in inner-city adults

BACKGROUND

Sensitivity and exposure to indoor allergens is associated with increased asthma morbidity in inner-city children. However, it is unknown whether sensitization is associated with worse asthma in adults.

OBJECTIVE

To evaluate the relationship between sensitization and asthma morbidity in urban adults.

METHODS

We prospectively studied 245 adults with persistent asthma recruited from an inner-city clinic. Sensitization to indoor allergens was evaluated by specific IgE antibodies measured at enrollment. Data on asthma control, asthma-related emergency department visits, hospitalizations, and oral steroid use were collected at baseline and at 1-month and 3-month follow-up contacts. Univariate, stratified, and multiple regression analyses were used to compare asthma morbidity in sensitized and nonsensitized patients after controlling for self-reported exposure and other potential confounders.

RESULTS

The study cohort consisted predominantly of low income, minority patients with high rates of resource utilization. The prevalences of sensitization to cockroach, dust mite, cat, mold, and mouse were 60%, 43%, 41%, 21%, and 14%. On univariate analyses, patients sensitized to each allergen did not have worse asthma control or higher resource utilization compared with nonsensitized individuals. Stratified and multivariate analyses also showed no association between sensitization and several measures of asthma morbidity even after controlling for self-reported exposure to indoor allergens and other potential confounders.

CONCLUSION

Sensitization to indoor allergens does not appear to be associated with increased asthma morbidity in inner-city adults.

CLINICAL IMPLICATIONS

These findings suggest that efforts to improve asthma control among urban populations should focus on other modifiable risk factors for morbidity.

Mortality and airflow obstruction in asthma: a 17-year follow-up study

BACKGROUND

Asthma is associated with fixed airflow obstruction and an increased risk of death. The aim of this study was to relate asthma mortality and airflow obstruction to severity of asthma in a cohort of patients with chronic asthma studied over a 17-year period.

METHODS

In 1980, asthma severity based on symptoms, asthma duration, treatment and smoking habits were assessed and lung function was measured after maximal therapy in 89 patients. In 1997, mortality was recorded and 44 of 60 patients known to be alive were restudied.

RESULTS

Eighteen patients had died: eight deaths were associated with asthma (seven occurred before and one after 1990). The risk of death was higher with decreased forced expiratory volume in 1 s (FEV1), increased FEV1 variability, age and treatment requirements but not symptom severity, at initial study. In the patients restudied, asthma severity and FEV1 variability decreased whereas the dose of inhaled corticosteriods increased 2.8-fold. Highest FEV1 was negatively related to treatment score and smoking history at initial study, but not at follow up and was <80% predicted in 19 (43%) patients, 11 of whom had never smoked. The mean (+/-standard deviation) decrement in FEV1 was 32 +/- 24 mL/year and correlated positively with FEV1 at initial study, smoking history, age of onset of asthma and treatment requirements at follow up.

CONCLUSION

In this cohort study, asthma was associated with chronic airflow obstruction and that with increased risk of mortality. Symptoms and mortality risk improved in association with increased reported use of inhaled corticosteroids; however, there was ongoing chronic airflow obstruction.

Asthma: defining of the persistent adult phenotypes

The common disease asthma is probably not a single disease, but rather a complex of multiple, separate syndromes that overlap. Although clinicians have recognised these different phenotypes for many years, they have remained poorly characterised, with little known about the underlying pathobiology contributing to them. Development of targeted therapies for asthma, and phenotype-specific clinical trials have raised interest in these phenotypes. Improved understanding of these phenotypes in complex diseases such as asthma will also improve our ability to link specific genotypes to their associated disease, which should help development of biomarkers. However, there is no standardised method to define asthma phenotypes. This Review analyses some of the methods that have been used to define asthma phenotypes and proposes an integrated method of classification to improve our understanding of these phenotypes.

A rational approach to the management of severe refractory asthma

Severe refractory asthma is a heterogeneous condition with different patterns of severity and different reasons for loss of asthma control. The three main patterns include asthma with frequent exacerbations, asthma with irreversible airway obstruction, and asthma with reduced sensitivity or resistance to corticosteroids. Each of these patterns has distinct risk factors. The assessment of patients with severe asthma requires a systematic, diagnostic and management protocol. The majority of patients will benefit from thorough analysis and treatment of aggravating factors. In some patients with severe refractory asthma, in particular those with concomitant chronic rhinosinusitis, long-term administration of systemic corticosteroids may be necessary. In these patients all efforts should be directed towards reducing the dose of corticosteroids as much as possible. Although several corticosteroid-sparing agents and immunosuppressants have been proposed in the literature, none of these has gained complete acceptance in clinical practice, either because of limited efficacy or unacceptable adverse effects. Novel potent anti-inflammatory therapies aimed at reducing the need for systemic corticosteroids in patients with severe, refractory asthma are urgently needed.

Clinical practice guidelines: medical follow-up of patients with asthma--adults and adolescents

The follow-up of patients with asthma should focus on asthma control (disease course over a number of weeks).

Asthma and incident cardiovascular disease: the Atherosclerosis Risk in Communities Study

BACKGROUND

A possible association between asthma and cardiovascular disease has been described in several exploratory studies.

METHODS

The association of self-reported, doctor diagnosed asthma and incident cardiovascular disease was examined in a biracial cohort of 45-64 year old adults (N = 13501) followed over 14 years.

RESULTS

Compared with never having asthma, the multivariate adjusted hazard ratio (HR) of stroke (n = 438) was 1.50 (95% CI 1.04 to 2.15) for a baseline report of ever having asthma (prevalence 5.2%) and 1.55 (95% CI 0.95 to 2.52) for current asthma (prevalence 2.7%). The relative risk of stroke was 1.43 (95% CI 1.03 to 1.98) using a time dependent analysis incorporating follow up reports of asthma. Participants reporting wheeze attacks with shortness of breath also had greater risk for stroke (HR = 1.56, 95% CI 1.18 to 2.06) than participants without these symptoms. The multivariate adjusted relative risk of coronary heart disease (n = 1349) was 0.87 (95% CI 0.66 to 1.14) for ever having asthma, 0.69 (95% CI 0.46 to 1.05) for current asthma at baseline, and 0.88 (95% CI 0.69 to 1.11) using the time dependent analysis.

CONCLUSIONS

Asthma may be an independent risk factor for incident stroke but not coronary heart disease in middle aged adults. This finding warrants replication and may motivate a search for possible mechanisms that link asthma and stroke.