Analysis of perimenstrual asthma based on questionnaire surveys in Japan

Sex Disparities in Asthma Development and Clinical Outcomes: Implications for Treatment Strategies

A gender-related disparity exists in asthma morbidity and mortality, which shifts at around puberty from a male predominance to a female predominance. This is clinically reflected in the fact that asthma that occurs in childhood (childhood-onset asthma) mainly affects boys, and that asthma that occurs in adulthood (adult-onset asthma) mainly affects women. Adult-onset asthma is often non-atopic, more severe, and associated with a poorer prognosis, thus posing a marked burden to women’s health and healthcare system. Many factors have been indicated to explain this gender-related disparity, including sociocultural and environmental factors as well as biological sex differences (genetic, pulmonary and immunological factors). It has long been suggested that sex hormones may be implicated in at least these biological sex differences. Overall, the evidence remains equivocal for the role of most sex hormones in asthma pathogenesis and clinical outcomes. Well-designed randomized clinical trials are required assessing the potential preventive or therapeutic effects of hormonal contraceptives on asthma in women, thereby helping to advance the evidence to inform future practice guidelines. The mechanisms underlying the role of sex hormones in asthma are complex, and our understanding is not yet complete. Additional mechanistic studies elucidating sex hormone signaling pathways and their interactions involved in the pathogenesis and clinical manifestations of asthma will help to identify potential sex hormone-driven asthma endotypes and novel therapeutic targets, providing the basis for a more personalized asthma management strategy.

Sex and gender in asthma

Asthma is a heterogenous disease, and its prevalence and severity are different in males versus females through various ages. As children, boys have an increased prevalence of asthma. As adults, women have an increased prevalence and severity of asthma. Sex hormones, genetic and epigenetic variations, social and environmental factors, and responses to asthma therapeutics are important factors in the sex differences observed in asthma incidence, prevalence and severity. For women, fluctuations in sex hormone levels during puberty, the menstrual cycle and pregnancy are associated with asthma pathogenesis. Further, sex differences in gene expression and epigenetic modifications and responses to environmental factors, including SARS-CoV-2 infections, are associated with differences in asthma incidence, prevalence and symptoms. We review the role of sex hormones, genetics and epigenetics, and their interactions with the environment in the clinical manifestations and therapeutic response of asthma.

Perimenstrual Asthma in Aspirin-Exacerbated Respiratory Disease

BACKGROUND

Aspirin-exacerbated respiratory disease (AERD) is a condition of the upper and lower respiratory tract characterized by reactions to nonsteroidal anti-inflammatory drugs. The Severe Asthma Research Program reported a strong association between perimenstrual asthma (PMA) and aspirin-sensitive asthma.

OBJECTIVE

To evaluate the prevalence and characteristics of PMA among a cohort of patients with AERD.

METHODS

Women 18 years and older enrolled in the Brigham and Women's AERD registry were surveyed about their reproductive, asthma, and sinus history. Subjects reporting the development of asthma before menopause were included. Continuous and categorical variables were compared between those reporting menstruation as a trigger for asthma symptoms and those who did not. Covariates expected a priori to have a positive effect on the odds of PMA were included in a multivariate logistic regression model to test associations between PMA and clinical factors.

RESULTS

Among females of childbearing potential, 369 of 695 responded to the survey and 322 met inclusion criteria. Twenty-four percent of subjects (n = 74) reported PMA. Earlier age of AERD onset, concurrent worsening of sinus symptoms the week before or during menstruation, increased emergency department visits for asthma, and a change in the severity of respiratory symptoms at menopause were more common in PMA. Earlier age at first nonsteroidal anti-inflammatory drug-induced respiratory reaction and emergency department visits increased the odds of reporting PMA.

CONCLUSIONS

PMA and increased sinus symptoms with menstruation are common in females with AERD. Females with AERD should be counseled about upper and lower respiratory symptom deterioration with menstruation.

Studying allergic inflammation and spirometry over menstrual cycles in well-controlled asthmatic women: Changes in progesterone and estradiol affect neither FENO levels nor lung function

It has been reported that female sex hormones influence on allergic inflammation and ventilation parameters in asthma but conclusions drawn by different researchers are divergent. The aim of our study was to assess the impact of progesterone (Pg) and estradiol (E) on the dynamics of allergic inflammation and spirometry test results in regularly menstruating women with stable allergic asthma. 13 women (28 days menstrual cycle), aged 18-45, taking no hormonal contraceptives, with mild and moderate asthma, without reported exacerbations at the near-ovulation and/or menstruation time, were monitored during two consecutive menstrual cycles. They had 4 visits per cycle (the first day of menstruation was assumed to be day 1 of the cycle; visits were carried out on days: 3-4, 10-11, 13-14 and 23-24). At each visit asthma symptoms, asthma control test (ACT) results, asthma treatment, fractioned nitric oxide (FENO) levels, spirometry test results, Pg and E, levels were analyzed. As a result of the study, no essential variability in FENO values and ventilation parameters' values in the course of menstruation cycle were observed. Negative correlation between FENO values and Pg concentrations was demonstrated (r = 0.27), but no correlation between FENO values and E levels was shown. No relationship between the ACT values and ventilation parameters and the levels of the sex hormones under investigation was detected. We conclude that changing levels of estradiol and progesterone (regardless of the negative correlation of progesterone and FENO values) affect neither the dynamics of allergic inflammation nor pulmonary function in women with stable allergic mild/moderate asthma.

Bronchial hyperreactivity in perimenstrual asthma is associated with increased Th-2 response in lower airways

BACKGROUND

Perimenstrual asthma (PMA) is a commonly observed, usually difficult-to-treat asthma phenotype. The mechanisms underlying this phenomenon remain unexplained. The aim of the study was to assess the degree of airway hyperresponsiveness and its relationship to proinflammatory cytokines concentration in lower airways of PMA compared to non-PMA patients.

METHODS

Premenopausal women with regular menstrual cycles diagnosed as: PMA (n=12), non-PMA asthmatics (n=9), and healthy controls (n=10) were prospectively followed for 10 weeks over two consecutive menstrual cycles. The bronchial responsiveness (BR) test to methacholine was performed in each subject prior to the study. The serum for total immunoglobulin E (IgE) concentrations was taken and sputum was induced in the 26th day of each of the two cycles. Sputum concentration of eotaxin, IL-4 and IL-10 were measured by ELISA.

RESULTS

Levels of BR to metacholine as well, as total blood IgE concentrations in PMA subjects were significantly higher than in non-PMA asthmatics and healthy controls (P=0.001, P=0.022 respectively) and correlated with each other (P=0.030; r =-0.65). Sputum eotaxin and IL-4 concentrations in luteal phase were increased in PMA patients when compared with non-PMA asthmatics (P=0.016; P=0.041, respectively) and healthy subjects (P<0.001 both cytokines). No differences for the sputum levels of IL-10 among studied groups were seen.

CONCLUSIONS

BR level in perimenstrual asthma is higher than in non-PMA asthmatics and correlates with increased total IgE serum concentration. The increased level of BR in PMA patients is associated with a shift in the type-1/type-2 cytokine balance toward a type-2 response.

[Features of asthma in women: what is the relationship with hormonal status?]

INTRODUCTION

The prevalence and control of asthma are modulated by hormonal changes in women, suggesting an influence of sex hormones on the airways.

BACKGROUND

The blood levels of both oestrogens and progesterone can modulate airway tone and inflammation. Asthma prevalence changes at puberty and the menopause, events also associated with modifications of adipose tissue and behaviour. Changes in lung function and asthma control are well documented during the menstrual cycle. However, an effect of hormone therapy on asthma control has not been demonstrated.

PERSPECTIVE

The effect of a targeted hormonal therapeutic intervention in menopausal asthma, a phenotype, which is frequently particularly severe, or in premenstrual asthma, should be evaluated by randomized trials.

CONCLUSION

Involvement of sex hormones and their cyclical variations in the characteristics of asthma in women is probable, despite lack of convincing data. However, no definitive protective or deleterious effect can be assigned. Complex interactions with adipose tissue, airways anatomy and the domestic or working environment must be taken into account to explain these differences.

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.

Leukotriene receptor antagonists pranlukast and montelukast for treating asthma

INTRODUCTION

The prevalence of bronchial asthma, which is a chronic inflammatory disorder of the airway, is increasing worldwide. Although inhaled corticosteroids (ICS) play a central role in the treatment of asthma, they cannot achieve good control for all asthmatics, and medications such as leukotriene receptor antagonists (LTRAs) with bronchodilatory and anti-inflammatory effects often serve as alternatives or add-on drugs.

AREAS COVERED

Clinical trials as well as basic studies of montelukast and pranlukast in animal models are ongoing. This review report clarifies the current status of these two LTRAs in the treatment of asthma and their future direction.

EXPERT OPINION

LTRAs could replace ICS as first-line medications for asthmatics who are refractory to ICS or cannot use inhalant devices. Further, LTRAs are recommended for asthmatics under specific circumstances that are closely associated with cysteinyl leukotrienes (cysLTs). Considering the low incidence of both severe adverse effects and the induction of tachyphylaxis, oral LTRAs should be more carefully considered for treating asthma in the clinical environment. Several issues such as predicted responses, effects of peripheral airway and airway remodeling and alternative administration routes remain to be clarified before LTRAs could serve a more effective role in the treatment of asthma.

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.

Menstrual cycle and respiratory symptoms in a general Nordic-Baltic population

RATIONALE

There is little knowledge of variations in respiratory symptoms during the menstrual cycle in a general population, and potential modifying factors are not investigated.

OBJECTIVES

To investigate menstrual cycle variation in respiratory symptoms in a large general population, using chronobiology methodology, and stratifying by body mass index (BMI), smoking, and asthma status.

METHODS

A total of 3,926 women with regular cycles less than or equal to 28 days and not taking exogenous sex hormones answered a postal questionnaire regarding the first day of their last menstruation and respiratory symptoms in the last 3 days. Moving 4-day means were computed to smooth uneven records of daily sampling; best-fitting 28-day composite cosine curves were applied to each time series to describe rhythmicity.

MEASUREMENTS AND MAIN RESULTS

Significant rhythmic variations over the menstrual cycle were found in each symptom for all subjects and subgroups. Wheezing was higher on cycle Days 10-22, with a midcycle dip near the time of putative ovulation (approximately Days 14-16) in most subgroups. Shortness of breath was higher on days 7-21, with a dip just before midcycle in many subgroups. Cough was higher just after putative ovulation for subjects with asthma, BMI greater than or equal to 23 kg/m(2), and smokers, or just before ovulation and menses onset for low symptomatic subgroups.

CONCLUSIONS

Respiratory symptoms varied significantly during the menstrual cycle and were most frequent from the midluteal to midfollicular stages, often with a dip near the time of ovulation. The patterns varied by BMI, smoking, and asthma status. These relations link respiratory symptoms with hormonal changes through the menstrual cycle and imply a potential for individualized chronotherapy for respiratory diseases.

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.

Clinical characteristics of women with menstrual-linked asthma

BACKGROUND

Menstrual-linked asthma (MLA) is described in pre-menopausal women who experience a deterioration of asthma control peri-menstrually. The clinical characteristics of MLA remain incompletely defined. Our objective was to define the characteristics of MLA in a large female asthma cohort.

METHODS

Cross-sectional population survey. A comprehensive health questionnaire that included questions about MLA was administered to 1260 consecutive female asthma patients aged 12-55 years. Univariate and multivariate analyses were completed.

RESULTS

The survey response rate was 43% (540/1260). The prevalence of self-reported MLA was 11% (60/540). Univariate: women with MLA compared to women without MLA had more urgent/emergent asthma-related healthcare visits/year, 6.18 (SD = ± 6.67) vs. 4.71 (SD = ± 5.91) (p=0.033), more emergency room visits, 1.50 (SD = ± 3.57) vs. 0.88 (SD = ± 2.27) (p=0.035), higher asthma-related absenteeism, 33/60 (57%) vs. 170/471 (37%) (p=0.003), and used almost twice the number of B(2)-agonist rescue doses/day, 1.13 (SD = ± 1.70) vs. 0.68 (SD = ± 1.32) (p=0.015). Multivariate: statistical significance was retained for absenteeism (p=0.016) and B(2)-agonist use (p=0.007) but lost for urgent healthcare visits (p=0.150) and emergency room visits (p=0.068).

CONCLUSIONS

Self-reported MLA is common. Women with MLA in our population had a greater frequency of urgent healthcare visits, a higher rate of absenteeism, and used significantly more B(2)-agonist rescue than women without MLA. The association of increased health services use was not confirmed on multivariate analysis indicating that baseline characteristics associated with MLA in our population affected this outcome. MLA should be considered by healthcare providers when developing an asthma management plan.

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.

Relation of perimenstrual asthma with disease severity and other allergic co-morbidities--the first report of perimenstrual asthma prevalence in Saudi Arabia

BACKGROUND

Perimenstrual asthma (PMA) has been documented in 30-40% of asthmatic women; however, there have been few epidemiological investigations of PMA in practice.

OBJECTIVES

Determination of the prevalence of perimenstrual asthma in a sample of female Saudi asthmatic patients, and to study the relation of PMA to asthma severity, aspirin-induced asthma and to other allergic co-morbidities.

STUDY DESIGN

Data were analysed from all female asthmatic patients followed up in the unit from January 2008 to May 2009 who were not pregnant, not on oral contraceptive pills, not menopausal, nor had had a hysterectomy. They were asked about exacerbation of their asthma state regarding worsening of symptoms, need for more rescue medications and even visits to emergency room just before or in the first days of menstruation, or both. Moreover, relation with aspirin-induced asthma and other associated allergic co-morbidities recorded in their medical files with prevalence of PMA was reported.

RESULTS

The prevalence was found to be 8.2%. Asthma severity was found to be significantly related to PMA (p<0.0001). Aspirin-induced asthma and allergic co-morbidities were more prone to occur in cases with PMA than other studied asthmatics.

CONCLUSION

We have found a low prevalence of PMA in Saudi women of fertile age compared to other studies published. Study findings support the hypothesis that PMA is related to asthma severity.

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.

Perimenstrual increase in bronchial hyperreactivity in premenopausal women: results from the population-based SAPALDIA 2 cohort

BACKGROUND

Studies on perimenstrual asthma are inconsistent, and different methodologies limit comparisons.

OBJECTIVE

To investigate cyclic variations in bronchial hyperreactivity (BHR) to methacholine in premenopausal women in a population-based cohort and assess effect modification by oral contraceptives (OCs).

METHODS

Day of menstruation cycle at the time of methacholine challenge was calculated in 571 menstruating women without hormonal treatment, age 28 to 58 years, on the basis of questionnaire data from the Swiss cohort study on Air Pollution And Lung Disease In Adults (SAPALDIA) cohort 2001/2002. A window of risk was defined 3 days before and after the first day of menstruation. Logistic and linear regression analyses were performed adjusting for main predictors of BHR and stratifying for asthma status. The impact of OCs was studied in the same sample enlarged by 130 women taking OCs.

RESULTS

The prevalence of BHR was 13% (fall of > or =20% in FEV(1) up to a maximal cumulative dose of 2 mg), and 6% had asthma. A total of 143 women had undergone methacholine challenge within the risk window. We observed a significant increase in BHR within the window of risk (odds ratio [OR], 2.3; 95% CI, 1.27-4.29). A cyclic association pattern was confirmed by trigonometric functions. Effect modification by asthma status and oral contraceptive use was found, with lower OR in subjects without asthma and OR <1 in women using OCs.

CONCLUSION

The data provide evidence of a systematic variation in BHR during the menstruation cycle, supporting the hypothesis of a hormonal influence. OCs appear to have a protective effect. Cyclicity of BHR could be of clinical importance in view of future medication recommendations and timing of respiratory function tests in women.

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

BACKGROUND

It is known that a wide variety of factors exacerbate asthma; however, few studies have investigated the factors that exacerbate asthma from a patient's perspective. The aim of this study was to analyze the factors that exacerbate asthma, based on a questionnaire completed by asthma patients in Niigata Prefecture.

METHODS

Based on questionnaires given to 3085 patients who visited the medical institutes in the Niigata Prefecture monthly from September through October 2006, groups stratified by sex, age, disease type and disease severity, were analyzed for factors contributing to asthma exacerbation, as described in the guideline of the Japanese Society of Allergology.

RESULTS

The leading exacerbating factor chosen by patients was a change in the weather, followed by smoking, allergen exposure, fatigue, stimulants, and air pollutants. Respiratory infection, widely recognized as a critical factor of severe exacerbation, was ranked seventh. Allergen exposure and air pollutants were prominent in younger individuals, whereas respiratory infection tended to be more common in elderly subjects. Allergen exposure, air pollutants, and exercise were significantly more common in atopic-type patients, in contrast with respiratory infection in non-atopic-type patients. According to multiple regression analysis, poor asthma control during the last one year was associated with changes in the weather, whereas the non-atopic disease type was related to exacerbation by respiratory infection. Current smoking was associated with both factors.

CONCLUSIONS

Many factors exacerbate asthma, depending on the individual case and his/her background. These data suggest that changes in the weather may be more important factor for patients in asthma exacerbation.

Premenstrual asthma: prevalence, cycle-to-cycle variability and relationship to oral contraceptive use and menstrual symptoms

The prevalence of asthma is higher in women than men of reproductive age and almost half of all hospitalisations for asthma in women occur during the perimenstrual phase of the cycle. The mechanisms of premenstrual asthma (PMA) are unknown and a definition of PMA has not been clearly presented in the literature. The objective of this study was to determine the prevalence of PMA using a variety of definitions, to investigate the cycle-to-cycle variation in PMA, the effects of oral contraceptive use and the relationship between PMA and premenstrual symptoms. Premenopausal women with asthma (n = 28) were prospectively followed for at least 12 weeks over 2-4 consecutive menstrual cycles. Asthma symptoms, beta(2)-agonist and inhaled corticosteroid use and morning and evening peak expiratory flow were recorded daily. The following types of PMA definitions were investigated: self-reported PMA, increased symptoms, increased medication use, decreased peak flow or a combination of changes in symptoms, medication and peak flow. Changes of more than 20%, for at least 2 consecutive days of the luteal phase (last 14 days of the cycle prior to menstruation) compared to the early follicular phase average (first 7 days after menstruation) were considered PMA. Using a composite definition where subjects experienced increased symptoms and medication use with or without a change in peak flow, 16 subjects were classified as having PMA (57%), while 12 did not have PMA. Only 4 subjects (25%) had PMA in every cycle examined. Fifty-five percent of subjects who used oral contraceptives had PMA, while 59% of subjects who did not use oral contraceptives had PMA. Women who were defined PMA using the composite definition were more likely than those without PMA to experience a 20% decrease in peak flow during the luteal phase. There was no relationship between asthma symptoms and premenstrual symptoms on day 1 of the menstrual cycle in women with PMA. PMA resulting in increased symptoms and medication use occurred in 57% of subjects studied for 2-4 menstrual cycles. The use of oral contraceptives is not protective and further work is required to elucidate the mechanisms of PMA.

Gender-medicine aspects in allergology

Despite the identical immunological mechanisms activating the release of mediators and consecutive symptoms in immediate-type allergy, there is still a clear clinical difference between female and male allergic patients. Even though the risk of being allergic is greater for boys in childhood, almost from adolescence onwards it seems to be a clear disadvantage to be a woman as far as atopic disorders are concerned. Asthma, food allergies and anaphylaxis are more frequently diagnosed in females. In turn, asthma and hay fever are associated with irregular menstruation. Pointing towards a role of sex hormones, an association of asthma and intake of contraceptives, and a risk for asthma exacerbations during pregnancy have been observed. Moreover, peri- and postmenopausal women were reported to increasingly suffer from asthma, wheeze and hay fever, being even enhanced by hormone replacement therapy. This may be on account of the recently identified oestradiol-receptor-dependent mast-cell activation. As a paradox of nature, women may even become hypersensitive against their own sex hormones, resulting in positive reactivity upon intradermal injection of oestrogen or progesterone. More importantly, this specific hypersensitivity is associated with recurrent miscarriages. Even though there is a striking gender-specific bias in IgE-mediated allergic diseases, public awareness of this fact still remains minimal today.