An analysis of factors that exacerbate asthma, based on a Japanese questionnaire

Sex Plays a Multifaceted Role in Asthma Pathogenesis

Sex is considered an important risk factor for asthma onset and exacerbation. The prevalence of asthma is higher in boys than in girls during childhood, which shows a reverse trend after puberty—it becomes higher in adult females than in adult males. In addition, asthma severity, characterized by the rate of hospitalization and relapse after discharge from the emergency department, is higher in female patients. Basic research indicates that female sex hormones enhance type 2 adaptive immune responses, and male sex hormones negatively regulate type 2 innate immune responses. However, whether hormone replacement therapy in postmenopausal women increases the risk of current asthma and asthma onset remains controversial in clinical settings. Recently, sex has also been shown to influence the pathophysiology of asthma in its relationship with genetic or other environmental factors, which modulate asthmatic immune responses in the airway mucosa. In this narrative review, we highlight the role of sex in the continuity of the asthmatic immune response from sensing allergens to Th2 cell activation based on our own data. In addition, we elucidate the interactive role of sex with genetic or environmental factors in asthma exacerbation in women.

Chronic Stress and Glucocorticoid Receptor Resistance in Asthma

PURPOSE

Chronic and persistent exposure to negative stress can lead to adverse consequences on health. Particularly, psychosocial factors were found to increase the risk and outcome of respiratory diseases like asthma. Glucocorticoids (GCs) are the most efficient anti-inflammatory therapy for asthma. However, a significant proportion of patients don't respond adequately to GC administration. GC sensitivity is modulated by genetic and acquired disease-related factors. Additionally, it was proposed that endogenous corticosteroids may limit certain actions of synthetic GCs, contributing to insensitivity. Psychological and physiological stresses activate the hypothalamic-pituitary-adrenal axis, increasing cortisol levels. Here, we review the mechanism involved in altered GC sensitivity in asthmatic patients under stressful situations. Strategies for modulation GC sensitivity and improving GC therapy are discussed.

METHODS

PubMed was searched for publications on psychological chronic stress and asthma, GC resistance in asthma, biological mechanisms for GC resistance, and drugs for steroid-resistant asthma, including highly potent GCs.

FINDINGS

GC resistance in patients with severe disease remains a major clinical problem. In asthma, experimental and clinical evidence suggests that chronic stress induces inflammatory changes, contributing to a worse GC response. GC resistant patients can be treated with other broad-spectrum anti-inflammatory drugs, but these generally have major side effects. Different mechanisms of GC resistance have been described and might be useful for developing new therapeutic strategies against it. Novel drugs, such as highly potent GCs, phosphoinositide 3-kinase-delta inhibitors that reestablish histone deacetylase-2 function, decrease of GC receptor phosphorylation by p38 mitogen-activated protein kinase inhibitors, or phosphatase activators, are currently in clinical development and might be combined with GC therapy in the future. Furthermore, microRNAs (small noncoding RNA molecules) operate as posttranscriptional regulators, providing another level of control of GC receptor levels. Empirical results allow postulating that the detection and study of microRNAs might be a promising approach to better characterize and treat asthmatic patients.

IMPLICATIONS

Many molecular and cellular pathobiological mechanisms are responsible of GC resistance. Therefore detecting specific biomarkers to help identify patients who would benefit from new therapies is crucial. Stress consitutes a negative aspect of current lifestyles that increase asthma morbidity and mortality. Adequate stress management could be an important and positive intervention.

Protective effect of heart rate variability biofeedback on stress-induced lung function impairment in asthma

Psychological stress can provoke airway constriction in asthmatic patients, which may be because of autonomic nervous system dysfunction in asthma. We investigated the effect of enhancing respiratory sinus arrhythmia using heart rate variability biofeedback (HRV-BF) on spirometry performance and HRV indices during stress induced by Stroop Color-Word interference test in asthmatic patients and healthy volunteers. Stress caused decrease in FEV1%, FVC%, and PEF% compared to baseline in asthmatic patients, but not in healthy subjects. A single short duration episode of HRV-BF not only had a protective effect on stress-induced airway constriction, but also significantly augmented the level of FEV1% and FVC% as compared with their own baseline. Also, there was a significant correlation between HRV changes and the augmentation of spirometry performance in asthmatic patients receiving HRV-BF. Our findings indicated that even a single short duration episode of HRV-BF can decrease susceptibility to stress-induced lung function impairment in patients with asthma, which may be through the modulation of respiratory sinus arrhythmia.

The interplay between neuroendocrine activity and psychological stress-induced exacerbation of allergic asthma

Psychological stress is recognized as a key factor in the exacerbation of allergic asthma, whereby brain responses to stress act as immunomodulators for asthma. In particular, stress-induced enhanced type 2 T-helper (Th2)-type lung inflammation is strongly associated with asthma pathogenesis. Psychological stress leads to eosinophilic airway inflammation through activation of the hypothalamic-pituitary-adrenal pathway and autonomic nervous system. This is followed by the secretion of stress hormones into the blood, including glucocorticoids, epinephrine, and norepinephrine, which enhance Th2 and type 17 T-helper (Th17)-type asthma profiles in humans and rodents. Recent evidence has shown that a defect of the μ-opioid receptor in the brain along with a defect of the peripheral glucocorticoid receptor signaling completely disrupted stress-induced airway inflammation in mice. This suggests that the stress response facilitates events in the central nervous and endocrine systems, thus exacerbating asthma. In this review, we outline the recent findings on the interplay between stress and neuroendocrine activities followed by stress-induced enhanced Th2 and Th17 immune responses and attenuated regulatory T (Treg) cell responses that are closely linked with asthma exacerbation. We will place a special focus on our own data that has emphasized the continuity from central sensing of psychological stress to enhanced eosinophilic airway inflammation. The mechanism that modulates psychological stress-induced exacerbation of allergic asthma through neuroendocrine activities is thought to involve a series of consecutive pathological events from the brain to the lung, which implies there to be a "neuropsychiatry phenotype" in asthma.

Phenotypic analysis of asthma in Japanese athletes

BACKGROUND

Asthma in athlete populations such as Olympic athletes has various pathogeneses. However, few reports are available on the features of asthma in the athlete population in clinical practice. In this study, we focused on classifying asthma in Japanese athlete population.

METHODS

We performed a cluster analysis of data from pulmonary function tests and clinical biomarkers before administering inhaled corticosteroids (ICS) therapy in athlete population of individuals diagnosed with asthma (n = 104; male, 76.9%; median age, 16.0 years), based on respiratory symptoms and positive data on methacholine provocation tests. We also compared backgrounds, sports types, and treatments between clusters.

RESULTS

Three clusters were identified. Cluster 1 (32%) comprised athletes with a less atopic phenotype and normal pulmonary function. Cluster 2 (44%) comprised athletes with a less atopic phenotype and lower percent predicted forced expiratory volume in 1 s (%FEV₁) values, despite less symptomatic state. Cluster 3 (24%) comprised athletes with a strong atopic phenotype such as high eosinophil count in the blood and total serum immunoglobulin E level. After treatment with ICS or ICS plus long-acting β-adrenergic receptor agonist for 6-12 months, %FEV₁ values were significantly improved in Cluster 2 athletes, whereas Cluster 3 athletes had a significant decrease in the fraction of exhaled nitric oxide compared to pretreatment values.

CONCLUSIONS

These data suggest three clusters exist in Japanese athlete population with asthma. Between the clusters, the characteristics differed with regard to symptoms, atopic features, and lower %FEV₁ values. The pathogeneses between clusters may vary depending on the inflammation type and airway hyperresponsiveness.

Neuropsychiatry phenotype in asthma: Psychological stress-induced alterations of the neuroendocrine-immune system in allergic airway inflammation

Since the recognition of asthma as a syndrome with complex pathophysiological signs and symptoms, recent research has sought to classify asthma phenotypes based on its clinical and molecular pathological features. Psychological stress was first recognized as a potential immune system modulator of asthma at the end of the 19th century. The activation of the central nervous system (CNS) upon exposure to psychological stress is integral for the initiation of signal transduction processes. The stress hormones, including glucocorticoids, epinephrine, and norepinephrine, which are secreted following CNS activation, are involved in the immunological alterations involved in psychological stress-induced asthma exacerbation. The mechanisms underlying this process may involve a pathological series of events from the brain to the lungs, which is attracting attention as a conceptually advanced phenotype in asthma pathogenesis. This review presents insights into the critical role of psychological stress in the development and exacerbation of allergic asthma, with a special focus on our own data that emphasizes on the continuity from the central sensing of psychological stress to enhanced eosinophilic airway inflammation.

Asthma and influenza vaccination in elderly hospitalized patients: Matched case-control study in Spain

OBJECTIVES

Influenza infection is an exacerbating factor for asthma, and its prevention is critical in managing asthmatic patients. We investigated the effect of influenza vaccination on asthmatic and non-asthmatic patients hospitalized with laboratory-confirmed influenza in Spain.

METHODS

We made a matched case-control study to assess the frequency of hospitalization for influenza in people aged ≥65 years. Hospitalized patients with unplanned hospital admissions were recruited from 20 hospitals representing seven Spanish regions. Cases were defined as those hospitalized due to a laboratory-confirmed influenza infection and controls were matched by age, sex, and hospital. Data were obtained from clinical records, and patients stratified by clinical asthma history. Vaccination status and asthma due to influenza infection were analyzed according to sociodemographic variables and medical risk conditions. Multivariable analysis was made using conditional logistic regression models.

RESULTS

582 hospitalized patients with influenza (15.8% asthmatic) and 1,570 hospitalized patients without influenza (7.9% asthmatic) were included. In the multivariable conditional logistic regression using unvaccinated and non-asthmatic patients as the reference group, vaccination significantly prevented influenza in non-asthmatic patients (aOR = 0.63; 95% CI: 0.45, 0.88) and also showed a trend for a possibly protective effect in asthmatic patients (aOR = 0.79; 95% CI: 0.34, 1.81).

CONCLUSION

Our results suggest that influenza vaccination could be a protective factor for asthmatic patients, although the results are inconclusive and further research is required. Practically, given the better clinical evolution of vaccinated asthma cases, and the lack of better evidence, the emphasis on vaccination of this group should continue.

Environmental factors affecting seasonality of ambulance emergency service visits for exacerbations of asthma and COPD

OBJECTIVE

The aim of this study was to assess the association of severe exacerbations of asthma and Chronic Obstructive Pulmonary Disease (COPD) requiring ambulance emergency service (AES) visits with meteorological parameters and influenza outbreaks.

METHODS

The records of patients calling the AES in 2007 and 2008 in the urban area of Lodz due to dyspnea were analyzed. Information on 25 daily reported meteorological parameters was obtained from the local meteorological service and data on influenza outbreaks obtained from the national surveillance service.

RESULTS

During the winter months, a significantly higher mean daily number of AES visits for both COPD and asthma were noticed when compared to the summer. Interestingly, the number of daily AES visits correlated with several weather parameters, and the multiple regression analysis confirmed a negative correlation with minimum temperature, mean temperature and the dew point for both diseases (R = 0.526; p < 0.01; R = 0.577; p < 0.01 and R = 0.589; p < 0.01). Furthermore, the increased number of AES visits also correlated with a new number of cases of influenza infections as reported by local influenza surveillance system (rs = 77.6%; p < 0.001 and rs = 80.8%; p < 0.001 for asthma and COPD, respectively).

CONCLUSION

Seasonality of AES visits for asthma and COPD are similar and seems to be related to specific weather conditions and to influenza outbreaks.

Analysis of the influenza A (H1N1) 2009 pandemic infection in Japanese asthmatic patients: using a questionnaire-based survey

BACKGROUND

Influenza infection is known to be an exacerbating factor in the control of asthma, therfore its prevention is critical in managing asthma. The aim of this study was to investigate the influenza A H1N1 2009 pandemic virus (H1N1 pdm09) infection in adult asthmatic patients.

METHODS

Data were obtained from a questionnaire-based survey of asthmatic patients conducted from September to October 2010 in Niigata Prefecture. Patient background, H1N1 pdm09 infection, vaccination status, and asthma exacerbation due to influenza infection were analyzed.

RESULTS

In total, 2,555 cases were analyzed. The incidence of the infection was 6.7% (95% confidence interval [CI]: 5.7-7.6), and the rate of vaccination was 63.9% (95% CI: 62.1-65.8). The odds ratio (OR) for vaccination against the infection among adult patients and younger patients (≤ the median age) were 0.61 (95% CI: 0.45-0.84) and 0.62 (95% CI: 0.42-0.90), respectively. However, OR among the older patient (> median age) were 1.38 (95%CI: 0.66-2.89). The rate of infection-induced asthma exacerbation was 23.2% (95% CI: 18.6-29.6), and the OR for vaccination against the infection-induced asthma exacerbation was 1.42 (95% CI: 0.69-2.92).

CONCLUSIONS

The effectiveness of the vaccination against the H1N1 pdm09 virus was confirmed during the first pandemic season, but it was limited. Further investigation on H1N1 pdm09 virus infection in asthmatics will be required.

Cluster analysis identifies characteristic phenotypes of asthma with accelerated lung function decline

OBJECTIVE

While the majority of individuals with asthma retain normal lung function over time, some exhibit accelerated lung function decline. Preservation of lung function is an important aspect of asthma management. Whether the asthma guidelines can prevent lung function decline remains controversial. This study was performed to determine the distribution of asthmatic subjects with greater lung function decline and to identify characteristic clinical features of such subjects treated in accordance with clinical guidelines by using hierarchical cluster analysis.

METHODS

Eighty-six asthmatic subjects without a history of smoking were assessed with respect to eight variables selected from clinical phenotypes by using step-wise multiple regression analysis. Hierarchical cluster analysis using Ward's method generated a dendrogram for estimation of the number of clusters within the population and the differences between them.

RESULTS

Three distinct clusters were identified. Cluster 1 (n = 40) comprised women with late-onset asthma. Cluster 2 (n = 17) comprised subjects with early-onset asthma, atopy and long disease duration. Cluster 3 (n = 29) predominantly comprised older men who had late-onset asthma, a lower prevalence of exacerbation and a lower predicted % forced expiratory volume in 1 s (FEV1) at baseline. Subjects in cluster 3 showed a mean decline in FEV1 of 69 mL/year, which was the greatest lung function decline among the three clusters.

CONCLUSION

We identified a subgroup of patients with accelerated lung function decline despite appropriate asthma treatment based on guidelines constructed by using subjective symptoms.

The Asthma Control Test, Japanese version (ACT-J) as a predictor of Global Initiative for Asthma (GINA) guideline-defined asthma control: analysis of a questionnaire-based survey

BACKGROUND

The 2006 Global Initiative for Asthma (GINA 2006) guidelines emphasize the importance of evaluating the control rather than the severity of asthma. The Asthma Control Test (ACT) is well known to be an excellent tool for evaluating asthma control in the clinical setting. This study aimed to evaluate the ACT, Japanese version (ACT-J) as a predictor of asthma control as defined by the GINA 2006 guidelines in actual clinical practice.

METHODS

A cross-sectional analysis comparing the ACT-J score and GINA classification of asthma control among 419 patients of primary care physicians and specialists was performed using the data from a 2010 questionnaire-based survey conducted by the Niigata Asthma Treatment Study Group.

RESULTS

The optimal cut-off point of the ACT-J score for predicting GINA-defined asthma control was 23, with ACT-J scores of ≥23 and ≤22 predicting controlled and uncontrolled asthma with area under the receiver operating characteristics curve values of 0.76 [95% confidence interval (CI): 0.72-0.81] and 0.93 [95% CI: 0.90-0.97], respectively.

CONCLUSIONS

ACT scores of ≥23 and ≤22 are useful for identifying patients with controlled and uncontrolled asthma, respectively, as defined by GINA 2006, and the latter is more strongly predictive than the former. The reason for the higher cut-off point of the ACT-J relative to other versions of the ACT is unclear and warrants further investigation.

Efficacy of using the Japanese version of the asthma control test for determing the level of asthma control in clinical settings

BACKGROUND

The Asthma Control Test (ACT) is frequently used for the evaluation of asthma control in clinical care setting because it does not require the use of pulmonary function tests, which can be difficult for general practitioners to use. However, few large-scale studies have investigated the efficacy of the Japanese version ACT (J-ACT) in actual use during clinical care.

METHODS

The aim of this study was to analyze the efficacy of the J-ACT in a clinical care setting. Using data from a 2008 questionnaire survey including the J-ACT by the Niigata Asthma Treatment Study Group, we compared the ACT scores of 2233 patients with respect to multiple parameters, including the severity by Japanese Society of Allergology and the attack frequency. Using the definition of asthma control partially referred to Global Initiative for Asthma (GINA) guidelines from the survey data, the accuracy screening and determination of optimal ACT cutpoints were performed by retrospective analysis.

RESULTS

Cronbach's α for the J-ACT was 0.785. Patients with more severe asthma and more frequent asthma attacks had lower ACT scores than did patients with less severe, less frequent attacks. The optimal ACT cutpoints were 24 for the controlled asthma and 20 for the uncontrolled asthma.

CONCLUSIONS

Our study, the first large-scale investigation of the efficacy of the J-ACT, determined that this evaluation tool is highly efficacious in establishing the level of asthma control. However, the determination of accurate cutpoints for the J-ACT will require more clear definitions of asthma control in future prospective studies.

Influence of underweight on asthma control

BACKGROUND

Although the association between asthma control and body mass index (BMI) has been thoroughly investigated, most of this work has focused on the influence on asthma incidence or the effect of obesity on asthma control. To date, there have been no published studies on the influence of underweight on asthma control.

METHODS

The aim of this study was to investigate the influence of underweight, as defined by the Japan Society for the Study of Obesity (JASSO), on asthma control in Japanese asthmatic patients. Using data from questionnaire surveys administered by the Niigata Asthma Treatment Study Group, we compared asthma control, as measured by the Asthma Control Test (ACT), between a normal weight group (18.5kg/m2 =< BMI < 25kg/m2) and an underweight group (BMI < 18.5kg/m2).

RESULTS

Of the asthmatic patients who completed the 2008 and 2010 surveys, 1464 and 1260 cases were classified as being in the normal weight group, and 174 and 155 cases were classified as being in the underweight group. The ACT score (median, [interquartile range]) in the underweight group in 2008 (22, [19-24]) and 2010 (23, [19-25]) was significantly lower than that in the normal group in 2008 (23, [20-25]) and in 2010 (24, [21-25]).

CONCLUSIONS

This study is the first, large-scale investigation of the influence of underweight on asthma control, and we have confirmed an adverse influence in a clinical setting. A potential mechanism for this interaction was unknown. Further investigation will be required.

Analysis of depression in asthmatic patients using the Japanese version of Patient Health Questionnaire-9

BACKGROUND

Previous studies show that depression plays an important role in asthma. However, the association between asthma control and severity, and depression is inconclusive.

METHODS

To investigate the association between asthma control and severity, and depression, we assessed differences in asthma control and asthma severity between groups with various grades of depressive state as defined by the PHQ-9 score using data from the Japanese version of Patient Health Questionnaire-9 (J-PHQ-9) and a questionnaire survey including the Asthma Control Test (ACT).

RESULTS

The ACT scores in the symptom-screen positive (SP) and major/other depressive disorder (MDD/ODD) group were significantly lower than those in the symptom-screen negative (SN) and non-MDD/ODD groups, respectively. The rate of step1 and of step 3 and 4 in the SP group were significantly lower and higher than those in the SN group, respectively. When the SP group was divided into three, that is minimal, mild, and more than mild (MTM) depressive state subgroups, the ACT scores in the mild and MTM depressive state subgroups were significantly lower than those in the minimal depressive state subgroup. When the MTM subgroup was divided into moderate, moderate-severe and severe depressive state groups, however, there was no significant variation in ACT score and asthma severity among these three depressive state groups.

CONCLUSIONS

This study is the first, large-scale investigation of the use of the J-PHQ-9 in asthma patients. Using the J-PHQ-9 and the questionnaire, there was a clear association between asthma control and severity, and depression. As the depression became more severe, the existence of other depression-associated factors unrelated to asthma control and severity might be assumed, although further investigation will be required.

Asthma control and management changes in Japan: questionnaire survey

BACKGROUND

Despite the advances of asthma management and the accompanying improved asthma control, many problems related to asthma management still remain. The Niigata Asthma Treatment Study Group has been regularly collecting information via surveys since 1998 using a questionnaire, on problems related to asthma management; various studies on asthma management have been reported using data from the questionnaire.

METHODS

The aim of this study was to investigate the changes in asthma control and management for every two-year period using the data from 1998 to 2008; future problems requiring resolution were extracted and discussed.

RESULTS

The number of cases surveyed each year was about 3,000 (2,593-3,347 cases). The changes in the data from 1998 to 2008, including asthma attacks and symptoms rate, indicated the improvement of asthma control with the spread of medication according to the guidelines; of particular note, there was a 24.1% increase in the usage rate of inhaled corticosteroids during the study period. From 2002 to 2008, however, some asthmatic conditions seemed to show no improvement with regards to asthma control related to the rates of changes in peak flow meter use, leukotriene receptor antagonist use and oral sustained-released theophylline use. Moreover, there was no decrease in the occurrence of emergency episodes related to asthma deaths.

CONCLUSION

In the actual clinical setting, asthma control seems to be progressing well with the appropriate changes of medication according to the guidelines, and in part due to inhaled corticosteroid use. However, there were two problems which need to be addressed: 1) no improvement in some asthmatic conditions and 2) the occurrence of emergency episodes related to asthma deaths. In the future, it will be necessary to manage asthma in view of these points.

Influence of obesity on control in asthmatic Japanese patients defined by the Japanese definition of obesity

BACKGROUND Despite the use of inhaled corticosteroid (ICS) becoming increasingly widespread, many problems related to asthma management still need to be addressed. One of them, obesity, has been reported to exert a harmful influence on asthma control. However, there have been few reports focusing not only on both obesity and its influence on Japanese asthma patients but also on the Japanese definition of obesity, as defined by the Japan Society for the Study of Obesity (JASSO). AIMS & METHODS The aim of this study was to confirm the influence of obesity, as defined by the JASSO, on asthma management in Japanese asthmatic patients. Using data from the Niigata Asthma Treatment Study Group 2008 questionnaire survey, differences between the "normal" group (18.5 kg/m(2) ≤ BMI <25 kg/m(2)) and the "obese" group (25 kg/m(2) ≤ BMI) were analyzed. RESULTS There was a significantly lower step 1 rate (19.4% v.s. 26.8%) and a higher proportion of patients using inhaled salmeterol (43.6% v.s. 35.8%) and leukotriene receptor antagonist (49.8% v.s. 40.8%) in the obese group relative to the normal group, although there were no significant differences in indicators of asthma control, including asthma control test scores. CONCLUSION This study investigated influences of JASSO-defined obesity on asthma severity and management in a clinical setting in Japan. It is possible that there are strong interactions between asthma and obesity, such as obesity causing decreased ICS therapy efficacy and leukotriene (LT)-related inflammation, although further investigation is necessary.