Airway inflammation in premenstrual asthma

Personalized Treatment of Asthma: The Importance of Sex and Gender Differences

An individual's sex (nominally male or female, based on biological attributes) and gender (a complex term referring to socially constructed roles, behaviors, and expressions of identity) influence the clinical course of asthma in several ways. The physiologic development of the lungs and effects of sex hormones may explain why more boys than girls have asthma, and after puberty, more women than men have asthma. Female sex hormones have an impact throughout the life span and are associated with poor asthma control. Gender may influence exposure to asthma triggers, and sex and gender can influence the prevalence of comorbidities and interactions with health care professionals. Despite widely reported sex- and gender-based differences in asthma and asthma management, these issues frequently are not considered by health care professionals. There is also inconsistency regarding the use of "sex" and "gender" in scientific discourse; research is needed to define sex- and gender-based differences better and how they might interact to influence asthma outcomes. This review outlines the impact an individual's sex and gender can have on the pathogenesis, clinical course, diagnosis, treatment, and management of asthma.

Just breathe: a review of sex and gender in chronic lung disease

Chronic lung diseases are the third leading cause of death worldwide and are increasing in prevalence over time. Although much of our traditional understanding of health and disease is derived from study of the male of the species - be it animal or human - there is increasing evidence that sex and gender contribute to differences in disease risk, prevalence, presentation, severity, treatment approach, response and outcomes. Chronic obstructive pulmonary disease, asthma and bronchiectasis represent the most prevalent and studied chronic lung diseases and have key sex- and gender-based differences which are critical to consider and incorporate into clinical and research approaches. Mechanistic differences present opportunities for therapeutic development whereas behavioural and clinical differences on the part of patients and providers present opportunities for greater education and understanding at multiple levels. In this review, we seek to summarise the sex- and gender-based differences in key chronic lung diseases and outline the clinical and research implications for stakeholders.

Perimenstrual Asthma in Adolescents: A Shared Condition in Pediatric and Gynecological Endocrinology

Asthma is a frequent medical condition in adolescence. The worsening of the most common symptoms perimenstrually is defined as perimenstrual asthma (PMA). The cause of PMA remains unclear, but a role for hormonal milieu is plausible. Data on PMA in adolescents are limited, and its management is not fully established. We aimed to discuss the PMA phenomenon in young females from pathophysiology to preventive strategies, focusing on the relationship with the hormonal pattern. The fluctuation of estrogens at ovulation and before menstruation and the progesterone secretion during the luteal phase and its subsequent withdrawal seem to be the culprits, because the deterioration of asthma is cyclical during the luteal phase and/or during the first days of the menstrual cycle. Conventional asthma therapies are not always effective for PMA. Preventive strategies may include innovative hormonal contraception. Even a possible beneficial effect of other hormonal treatments, including estrogens, progestogens, and androgens, as well as leukotriene receptor antagonists and explorative approach using microbial-directed therapy, is considered. The underlying mechanisms, through which sex-hormone fluctuations influence asthma symptoms, represent a challenge in the clinical management of such a distressing condition. Further studies focused on young females are mandatory to promote adolescent health.

The Role of Comorbidities in Difficult-to-Control Asthma in Adults and Children

Assessment of asthma comorbidities, conditions that adversely affect the pathobiology of asthma or impair its response to therapies, is a fundamental step in the evaluation and management of patients with difficult-to-treat asthma. Identifying and effectively treating asthma comorbidities, such as obesity, obstructive sleep apnea, and chronic sinusitis with nasal polyps, may improve asthma control and reduce exacerbations. In addition, identifying comorbid T2 inflammatory conditions may help guide optimal selection of biologic therapies. Here, we describe common comorbid conditions found in adult and pediatric difficult-to-control asthma, discuss evidence for the association with asthma morbidity and treatment benefit, and provide information on how and when to assess comorbidities.

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.

Quality of life and asthma control related to hormonal transitions in women's lives

Objectives: The aim was to investigate if menstruation and use of exogenous sex hormones influence self-reported asthma related quality of life (QoL) and asthma control.Methods: The study is based on two asthma cohorts randomly selected in primary and secondary care. A total of 622 female patients 18-65 years were included and classified as premenopausal ≤46 years (n = 338) and peri/postmenopausal 47-65 years (n = 284). Questionnaire data from 2012 and 2014 with demographics, asthma related issues and sex hormone status. Outcome measures were Mini Asthma Quality of Life Questionnaire (Mini-AQLQ) and asthma control including Asthma Control Test (ACT) and exacerbations last six months.Results: Premenopausal women with menstruation related asthma worsening, perimenstrual asthma (PMA) (9%), had a clinically relevant lower Mini-AQLQ mean score 4.9 vs. 5.8 (p < 0.001), lower asthma control with ACT score <20, 72% vs. 28% (p < 0.001) and higher exacerbation frequency 44% vs. 20% (p = 0.004) compared with women without PMA. Women with irregular menstruation had higher exacerbation frequency than women with regular menstruation (p = 0.023). Hormonal contraceptives had no impact on QoL and asthma control. Peri/postmenopausal women with menopausal hormone therapy (MHT) had a clinically relevant lower Mini-AQLQ mean score compared to those without MHT, 4.9 vs 5.4 (p < 0.001), but no differences in asthma control.Conclusion: Women with PMA had lower QoL and more uncontrolled asthma than women without PMA. Peri/postmenopausal women with MHT had lower QoL than women without MHT. Individual clinical management of women with asthma may benefit from information about their sex hormone status.

The Specificities of Elite Female Athletes: A Multidisciplinary Approach

Female athletes have garnered considerable attention in the last few years as more and more women participate in sports events. However, despite the well-known repercussions of female sex hormones, few studies have investigated the specificities of elite female athletes. In this review, we present the current but still limited data on how normal menstrual phases, altered menstrual phases, and hormonal contraception affect both physical and cognitive performances in these elite athletes. To examine the implicated mechanisms, as well as the potential performances and health risks in this population, we then take a broader multidisciplinary approach and report on the causal/reciprocal relationships between hormonal status and mental and physical health in young (18-40 years) healthy females, both trained and untrained. We thus cover the research on both physiological and psychological variables, as well as on the Athlete Biological Passport used for anti-doping purposes. We consider the fairly frequent discrepancies and summarize the current knowledge in this new field of interest. Last, we conclude with some practical guidelines for eliciting improvements in physical and cognitive performance while minimizing the health risks for female athletes.

A Review of Evidence-Based Recommendations for Pericoronitis Management and a Systematic Review of Antibiotic Prescribing for Pericoronitis among Dentists: Inappropriate Pericoronitis Treatment Is a Critical Factor of Antibiotic Overuse in Dentistry

This work provides a narrative review covering evidence-based recommendations for pericoronitis management (Part A) and a systematic review of antibiotic prescribing for pericoronitis from January 2000 to May 2021 (Part B). Part A presents the most recent, clinically significant, and evidence-based guidance for pericoronitis diagnosis and proper treatment recommending the local therapy over antibiotic prescribing, which should be reserved for severe conditions. The systematic review includes publications analyzing sets of patients treated for pericoronitis and questionnaires that identified dentists’ therapeutic approaches to pericoronitis. Questionnaires among dentists revealed that almost 75% of them prescribed antibiotics for pericoronitis, and pericoronitis was among the top 4 in the frequency of antibiotic use within the surveyed diagnoses and situations. Studies involving patients showed that antibiotics were prescribed to more than half of the patients with pericoronitis, and pericoronitis was among the top 2 in the frequency of antibiotic use within the monitored diagnoses and situations. The most prescribed antibiotics for pericoronitis were amoxicillin and metronidazole. The systematic review results show abundant and unnecessary use of antibiotics for pericoronitis and are in strong contrast to evidence-based recommendations summarized in the narrative review. Adherence of dental professionals to the recommendations presented in this work can help rapidly reduce the duration of pericoronitis, prevent its complications, and reduce the use of antibiotics and thus reduce its impact on patients’ quality of life, healthcare costs, and antimicrobial resistance development.

Asthma, atopy, and exercise: Sex differences in exercise-induced bronchoconstriction

Asthma is a chronic inflammatory lung disease affecting approximately 7.7% of the US population. Sex differences in the prevalence, incidence, and severity of asthma have been widely described throughout the lifespan, showing higher rates in boys than girls before puberty, but a reversed pattern in adults. Asthma is often associated with atopy, i.e. the tendency to develop allergic diseases, and can be worsened by environmental stimuli and/or exercise. While not exclusive to patients with asthma, exercise-induced bronchoconstriction (EIB) is a common complication of athletes and individuals who exercise regularly. Currently, there is limited research on sex differences in EIB and its relationship with atopy and asthma in men and women. In this minireview, we summarize the available literature on this topic. Overall, the collective knowledge supports the notion that physiological changes triggered during exercise affect males and females differently, suggesting an interaction among sex, exercise, sex hormones, and atopic status in the course of EIB pathophysiology. Understanding these differences is important to provide personalized management plans to men and women who exercise regularly and suffer from underlying asthma and/or atopy.

[Woman's asthma throughout life: Towards a personalized management?]

In a woman's life, asthma can affect her in a variety of ways, with the onset of premenstrual asthma currently under-diagnosed. It is estimated that about 20% of women with asthma have premenstrual asthma, which is more common in patients with severe asthma. Women with asthma are at high risk of exacerbations and of severe asthma. Asthma is the most common chronic disease during pregnancy with potential maternal and foetal complications. Asthma medications are safe for the foetus and it is essential to continue pre-existing treatment and adapt it to the progress of asthma during the pregnancy. Sex steroids modulate the structure and function of bronchial and immune cells. Understanding their role in asthma pathogenesis is complicated by the ambivalent effects of bronchodilating and pro-inflammatory oestrogens as well as the diversity of response to their association with progesterone. Menopausal asthma is a clinical entity and is part of one of the phenotypes of severe non-allergic and low steroid-sensitive asthma. Targeted assessment of the domestic and professional environment allows optimization of asthma management.

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.

Hormones, sex, and asthma

OBJECTIVE

To summarize the current literature on the sex disparity in asthma and the role of sex hormone signaling in allergic and neutrophilic airway inflammation.

DATA SOURCES

PubMed and Centers for Disease Control and Prevention health surveys were searched.

STUDY SELECTIONS

Clinical and epidemiologic studies in children and adults as well as animal models of asthma were included in this review.

RESULTS

Compared with males, females have an increase in asthma prevalence starting around puberty, and fluctuations in hormones during menstruation, pregnancy, and menopause are associated with changes in asthma symptoms. Animal studies using genetic deletions of estrogen receptors or androgen receptors have shown that estrogen signaling promotes and androgen signaling attenuates allergen-mediated type 2 airway inflammation. Furthermore, animal studies have found that ovarian hormones are important for interleukin 17A-mediated airway inflammation.

CONCLUSION

Sex hormones are important in regulating asthma pathogenesis. However, additional studies need to be conducted to further elucidate how sex hormones are initiating and driving the inflammatory response(s) in asthma. Determining these pathways will provide the foundation necessary for the development of treatment strategies and potentially new therapeutics for patients, in particular females, with asthma.

Mechanisms Driving Gender Differences in Asthma

PURPOSE OF REVIEW

Many phenotypes of asthma exist, ranging from mild asthma with onset during childhood to severe asthma with later onset, making asthma a broad disease with different pathologies. A gender disparity exists in asthma prevalence. As adults, women have an increased asthma prevalence compared to men. Further, women are more likely to have severe asthma and a later onset of asthma compared to men. Here, we review clinical and animal studies that have defined the role of sex hormones in airway inflammation, smooth muscle contraction, mucus production, and airway mechanics associated with asthma pathogenesis.

RECENT FINDINGS

Clinical evidence shows that increased asthma symptoms occur in females starting at puberty compared to those in boys. However, after puberty, the role for sex hormones in regulating asthma symptoms during menstruation, pregnancy, and menopause is not as clear. Animal studies have shown that estrogen increases and testosterone decreases Th2-mediated airway inflammation, and that females have increased IL-17A-mediated airway inflammation compared to males. Further, females had increased DC and Mϕ function compared to males. However, the mechanisms driving the types of allergic inflammation are not fully elucidated. Overall, ovarian hormones increased and testosterone decreased airway inflammation in asthma, but the mechanisms remain unclear. Delineating these pathways using animal models as well as women and men with various phenotypes of asthma will help determine if women with asthma should take (or avoid) hormonal contraceptives as well as predict changes in asthma symptoms during life phases, including pregnancy and menopause, when sex hormones are dramatically changing.

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.

Asthma and gender: The female lung

Asthma is a common chronic disease that affects over 300 million people worldwide, resulting in a considerable socio-economic burden. Literature data suggest that asthma has a higher incidence in females, particularly at certain stages of pubertal development. Moreover, women seem to experience more asthma symptoms than men and to use more rescue medications, resulting in a reduced quality of life. Although several mechanisms have been proposed to explain these differences, there are not yet final data available in the literature on the role of gender in the pathogenesis of asthma and different behavior in females. Some study suggested a more prevalent hyper-responsiveness in women than in men. Nevertheless, in the literature definitive data on a possible different response to drugs used for asthma between males and females are not described. Understanding the mechanisms that underlie these gender differences in clinical history of asthma patients could give inspiration to new areas of research to obtain a more specific diagnostic and therapeutic approach gender-oriented.

Functional Characterization of Exonic Variants of the PPARGC1B Gene in Coregulation of Estrogen Receptor Alpha

Peroxisome proliferator-activated receptor gamma coactivator 1 beta (PPARGC1B) is a coactivator of estrogen receptor (ER)α and ERβ. We previously demonstrated a significant association between a variant of exon 5 of the PPARGC1B gene (+102525 G>A, R265Q) and airway hyperreactivity (AHR). The aims of the study were to evaluate the genetic effects of variants of the PPARGC1B gene on the function of ERs. PPARGC1B +102525G and A gene constructs were generated using PCR and cloned into a pCMV4 promoter vector. A luciferase reporter assay was undertaken in 293T cells cotransfected with one of the PPARGC1B +102525G>A constructs, ERα, and an estrogen response element (ERE) containing a luciferase construct after treatment with 17β-estradiol. According to the luciferase reporter assay, the +102525A allele showed higher ERα activity than the +102525G allele in response to stimulation with 17β-estradiol. In addition, the interaction between ERα and PPARGC1B was evaluated by coprecipitation assay. Human influenza hemagglutinin-tagged PPARGC1B coprecipitated more intensely with ERα in the +102525A than the +102525G construct after 17β estradiol treatment. The variant +102525A allele enhances the activity of ERα to a greater degree than the +102525G allele of PPARGC1B.

Sex differences in asthma symptom profiles and control in the American Lung Association Asthma Clinical Research Centers

OBJECTIVE

Important differences between men and women with asthma have been demonstrated, with women describing more symptoms and worse asthma-related quality of life (QOL) despite having similar or better pulmonary function. While current guidelines focus heavily on assessing asthma control, they lack information about whether sex-specific approaches to asthma assessment should be considered. We sought to determine if sex differences in asthma control or symptom profiles exist in the well-characterized population of participants in the American Lung Association Asthma Clinical Research Centers (ALA-ACRC) trials.

METHODS

We reviewed baseline data from four trials published by the ALA-ACRC to evaluate individual item responses to three standardized asthma questionnaires: the Juniper Asthma Control Questionnaire (ACQ), the multi-attribute Asthma Symptom Utility Index (ASUI), and Juniper Mini Asthma Quality of Life Questionnaire (mini-AQLQ).

RESULTS

In the poorly-controlled population, women reported similar overall asthma control (mean ACQ 1.9 vs. 1.8; p = 0.54), but were more likely to report specific symptoms such as nocturnal awakenings, activity limitations, and shortness of breath on individual item responses. Women reported worse asthma-related QOL on the mini-AQLQ (mean 4.5 vs. 4.9; p < 0.001) and more asthma-related symptoms with a lower mean score on the ASUI (0.73 vs. 0.77; p ≤ 0.0001) and were more likely to report feeling bothered by particular symptoms such as coughing, or environmental triggers.

CONCLUSIONS

In participants with poorly-controlled asthma, women had outwardly similar asthma control, but had unique symptom profiles on detailed item analyses which were evident on evaluation of three standardized asthma questionnaires.

Role of biomarkers in understanding and treating children with asthma: towards personalized care

Asthma is one of the most common chronic diseases affecting children. Despite publicized expert panels on asthma management and the availability of high-potency inhaled corticosteroids, asthma continues to pose an enormous burden on quality of life for children. Research into the genetic and molecular origins of asthma are starting to show how distinct disease entities exist within the syndrome of "asthma". Biomarkers can be used to diagnose underlying molecular mechanisms that can predict the natural course of disease or likely response to drug treatment. The progress of personalized medicine in the care of children with asthma is still in its infancy. We are not yet able to apply stratified asthma treatments based on molecular phenotypes, although that time may be fast approaching. This review discusses some of the recent advances in asthma genetics and the use of current biomarkers that can help guide improved treatment. For example, the fraction of expired nitric oxide and serum Immunoglobulin E (IgE) (including allergen-specific IgE), when evaluated in the context of recurrent asthma symptoms, are general predictors of allergic airway inflammation. Biomarker assays for secondhand tobacco smoke exposure and cysteinyl leukotrienes are both promising areas of study that can help personalize management, not just for pharmacologic management, but also education and prevention efforts.

Biological studies on the effect of estrogen on experimentally induced asthma in mice

This study evaluates the influence of estrogen hormone on the experimentally induced asthma in male mice. The animals were divided into four groups, with 20 mice in each group; group I (control mice) included mice that received no treatment, group II included mice that received intraperitoneal estrogen injection (0.25 mg/kg body weight (bw), twice on day 28 of the experiment), group III (asthmatic mice) included asthmatic mice that received intraperitoneal injection of two doses of ovalbumin (OVA; 2 µg of OVA mixed with 100 µg of aluminum potassium sulfate) on days 1 and 14 of the experiment and then challenged intranasally with a single dose of OVA (50 µg dissolved in 0.05 ml phosphate-buffered saline; PBS) on day 28 of the experiment, and group IV (asthmatic mice treated with estrogen) included asthma model male mice that received the estrogen (0.5 mg/kg bw in 40 ml PBS, twice on the day 28 of the experiment). The immunohistochemical studies observed a marked intensity of CD15 immunoreactivity in the lung tissues of asthma model mice. Physiological results recorded that the total and differential count of leukocytes in bronchoalveolar lavage fluid (BALF) of asthma model mice recorded a significant increase in the number of leukocytes especially in the number of eosinophil cells. The BALF of asthma model mice showed high levels of interleukins 4 and 5 (IL-4 and IL-5), and there was a significant decrease in both the levels of IL-4 and IL-5 in BALF of asthma model mice treated with estrogen. In conclusion, the obtained results indicated that the asthma is responsible for certain immunohistochemical and physiological alterations induced in lung tissues of mice. The administration of estrogen to asthmatic male mice could improve these changes. For this reason, the present findings support the possible role of estrogen in modulating the inflammatory effects caused by asthma in male mice and may be helpful to cure many asthmatic progressions.

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.

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.

Update on exhaled nitric oxide in pulmonary disease

The ability to assess the inflammatory status of a patient's airway using a noninvasive method is the ideal situation for clinicians. Owing in part to the relationship between the levels of exhaled nitric oxide to inflammation and the ease of the technique, the measurement of the fraction of exhaled nitric oxide (F(E)NO) has achieved considerable attention, particularly with respect to asthma. A multitude of studies have shown that when measured in exhaled air, this unique molecule has the potential to have both diagnostic and therapeutic roles in the clinical setting for many pulmonary diseases. The incorporation of F(E)NO into asthma management and treatment algorithms may help shed further insight on the current control and future risk of patients. Research is ongoing to determine the biology and the benefits of the use of F(E)NO in respiratory conditions in addition to asthma. This review will briefly outline the pathophysiology of nitric oxide, the measurement of F(E)NO and the potential clinical uses of F(E)NO in asthma and a number of other respiratory diseases. Despite its promise, until further research is conducted, the use of F(E)NO cannot be recommended for routine clinical management of respiratory diseases at present, but should be considered as an adjuvant to help guide therapy in certain patients with asthma and in those with eosinophilic bronchitis.

Genetic effect of single-nucleotide polymorphisms in the PPARGC1B gene on airway hyperreactivity in asthmatic patients

BACKGROUND

Peroxisome proliferator-activated receptor gamma coactivator 1 beta (PPARGC1B) is a co-activator for intracellular receptors such as the estrogen receptor, PPAR, and glucocorticoid receptor, which are involved in asthma development.

OBJECTIVES

Genetic association of single-nucleotide polymorphisms (SNPs) in the PPARGC1B gene with the risk of asthma and airway hyperreactivity (AHR) was investigated, as well as the functional effects of these SNPs on PPARGC1B gene and protein expression.

METHODS

Direct sequencing of DNA from 24 Korean was performed to identify PPARGC1B SNPs. Genotyping was done in 264 controls and 949 asthmatics using single-base extension methods. PPARGC1B mRNA levels were measured using real-time PCR methodology. Luciferase and electrophoretic mobility shift assays (EMSA) were performed to functionally analyse PPARGC1B SNPs on promoter.

RESULTS

Eighteen SNPs and one insertion/deletion polymorphism were identified, and seven SNPs were genotyped. No significant difference existed in the distribution of SNPs and haplotypes between the asthmatics and controls. However, the allele frequency of -427C>T and +102525G>A;R265Q showed a significant association with log-transformed PC(20) methacholine values in the asthmatics (P=0.005-0.0004). Real-time PCR demonstrated higher PPARGC1B mRNA levels in asthmatics having -427CC allele than in those having -427TT or CT alleles (P=0.048). The ratio of the mRNA expression for each PPARGC1B exon4-mRNA compared with the wild type was similar in peripheral blood mononuclear cells carrying the +102525G>A allele. Luciferase reporter assays revealed that -427C allele caused higher promoter activity than -427T allele. EMSA demonstrated that -427C allele exhibited stronger binding activity to a nuclear protein in 293T cells than did the -427T allele.

CONCLUSIONS AND CLINICAL RELEVANCE

Polymorphisms of -427C>T on the promoter and those of +102525G>A on exon 5 of the PPARGC1B gene may affect the development of AHR through the modulation of PPARGC1B gene products. The PPARGC1B genotypes may serve as genetic markers for AHR.

Asthma, the sex difference

PURPOSE OF REVIEW

asthma is a common chronic disease with significant clinical impact worldwide. Sex-related disparities in asthma epidemiology and morbidity exist but debate continues regarding the mechanisms for these differences. There is a need to review the recent findings for asthma care providers and to highlight areas in need of additional research.

RECENT FINDINGS

recent data illustrate striking sex-related differences in asthma epidemiology and disease expression. Studies show an increased incidence of asthma in women. Data demonstrate that asthmatic women have a poorer quality of life and increased utilization of healthcare compared to their male counterparts despite similar medical treatment and baseline pulmonary function. Research continues to explore hypotheses for these differences including the potential influences of the female sex hormones, altered perception of airflow obstruction, increased bronchial hyper-responsiveness, and medication compliance and technique. However, no single explanation has been able to fully explain the disparities.

SUMMARY

women are more likely to be diagnosed with asthma and suffer greater morbidity than men. The physiologic mechanisms for these differences are not well understood. Understanding sex-related differences in asthma and providing patients with education geared toward these disparities are important in establishing effective, individualized asthma management strategies for all patients.

Exhaled nitric oxide and influencing factors in a random population sample

The aim of the current study was to determine the impact and interaction of important influencing factors on the fraction of exhaled nitric oxide (FeNO). FeNO was measured in a population-based sample of 1250 middle-aged subjects from the KORA F4 cohort (Augsburg, Germany). Analysis of covariance models was performed including the factors age, height, FVC, FEV(1), sex, current smoking status, recent respiratory tract infection, and respiratory allergy. Geometric mean (SD as factor; 95% confidence interval as factor) FeNO was 13.9 (1.9; 1.033) ppb. FeNO significantly depended on age, height, smoking, infection and allergy. Smoking reduced FeNO by 21%, while infection and allergy led to increases by 9 and 11%, respectively. Increases in age by 10 years and in height by 10 cm were associated with increases of FeNO by 15 and 10%, respectively. Non-smokers demonstrated independent multiplicative superposition of factors affecting FeNO while the effect of allergy was virtually eliminated in smokers without infection. We conclude that in middle-aged non-smokers the effects of infection, age and height can be easily taken into account and do not significantly disturb the effect of respiratory tract allergies on FeNO. In current smokers, however, effects were heterogeneous and information on smoking intensity seems to be useful for better adjustment.

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.

Fractional exhaled nitric oxide in asthma: an update

In asthma, clinical symptoms and lung function are insensitive in reflecting the underlying airway inflammation, and monitoring of this process has only recently become available. Fractional exhaled nitric oxide (Fe(NO)) is now recognized as a reliable surrogate marker of eosinophilic airway inflammation and offers the advantage of being completely non-invasive and very easy to obtain. This review summarizes the clinical use of Fe(NO) in asthma. It covers the relationship between Fe(NO) and the underlying eosinophilic inflammation, the pathophysiology and production of Fe(NO), technical aspects of Fe(NO) measurement and potential confounding factors in interpreting levels. Fe(NO) reference values and the role of Fe(NO) in asthma assessment, diagnosis and management are also discussed.

Changes in exhaled nitric oxide related to estrogen and progesterone during the menstrual cycle

BACKGROUND

Significant changes in asthma and atopy occur throughout the menstrual cycle. We hypothesized that the characteristics of asthma (eg, symptoms, exhaled nitric oxide [eNO] levels as a marker of airway inflammation, pulmonary function, and atopy) vary throughout the menstrual cycle in relation to changes in the levels of estrogen or progesterone and that this variation is attenuated in women using oral contraception (OC).

METHODS

Seventeen women with asthma were studied over the course of their menstrual cycle through daily measurements of symptoms, eNO, spirometry, 17beta-estradiol, and progesterone levels, and through the performance of alternate-day allergy skin-prick tests (SPTs).

RESULTS

Of 534 potential daily visits, 526 (98.5%) were completed. Women not using OC (n = 8) had higher mean eNO levels (48.2 parts per billion [ppb]; 95% CI, 43.1 ppb to 53.3 ppb) than women using OC (27.0 ppb; 95% CI, 24.2 ppb to 29.7 ppb; p <or= 0.005). Among women not using OC, a 10 pmol/L increase in 17beta-estradiol levels was associated with a 15.2-ppm decrease in eNO levels (95% CI, -23.4 ppb to -7.0 ppm; p < 0.005). In contrast, an increase in progesterone level of 0.5 nmol/L was significantly associated with a 10.0-ppb increase in eNO (95% CI, 1.2 ppb to 18.7 ppb; p <or= 0.05). Consistent and significant results were found for 17beta-estradiol and progesterone levels and SPT. There were no significant associations between sex hormones and markers of asthma among women using OC.

CONCLUSION

During natural menstrual cycles, increases in estrogen levels were associated with decreased eNO levels, whereas increases in progesterone levels were associated with increased eNO levels and SPT wheal size. These effects were not observed among women using OC.

Effects of the menstrual cycle on lung function variables in women with asthma

RATIONALE

Angiogenesis is a defining pathologic feature of airway remodeling and contributes to asthma severity. Women experience changes in asthma control over the menstrual cycle, a time when vessels routinely form and regress under the control of angiogenic factors. One vital function modulated over the menstrual cycle in healthy women is gas transfer, and this has been related to angiogenesis and cyclic expansion of the pulmonary vascular bed.

OBJECTIVES

We hypothesized that changes in gas transfer and the pulmonary vascular bed occur in women with asthma over the menstrual cycle and are associated with worsening airflow obstruction.

METHODS

Twenty-three women, 13 with asthma and 10 healthy control subjects, were evaluated over the menstrual cycle with weekly measures of spirometry, gas transfer, nitric oxide, hemoglobin, factors affecting hemoglobin binding affinity, and proangiogenic factors.

MEASUREMENTS AND MAIN RESULTS

Airflow and lung diffusing capacity varied over the menstrual cycle with peak levels during menses that subsequently declined to nadir in early luteal phase. In contrast to healthy women, changes in lung diffusing capacity (DL(CO)) were associated with changes in membrane diffusing capacity and DL(CO) was not related to proangiogenic factors. DL(CO) did not differ between the two groups, although methemoglobin and carboxyhemoglobin were higher in women with asthma than in healthy women.

CONCLUSIONS

Women with asthma experience cyclic changes in airflow as well as gas transfer and membrane diffusing capacity supportive of a hormonal effect on lung function.

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.

Estrogen determines sex differences in airway responsiveness after allergen exposure

The female hormone estrogen is an important factor in the regulation of airway function and inflammation, and sex differences in the prevalence of asthma are well described. Using an animal model, we determined how sex differences may underlie the development of altered airway function in response to allergen exposure. We compared sex differences in the development of airway hyperresponsiveness (AHR) after allergen exposure exclusively via the airways. Ovalbumin (OVA) was administered by nebulization on 10 consecutive days in BALB/c mice. After methacholine challenge, significant AHR developed in male mice but not in female mice. Ovariectomized female mice showed significant AHR after 10-day OVA inhalation. ICI182,780, an estrogen antagonist, similarly enhanced airway responsiveness even when administered 1 hour before assay. In contrast, 17beta-estradiol dose-dependently suppressed AHR in male mice. In all cases, airway responsiveness was inhibited by the administration of a neurokinin 1 receptor antagonist. These results demonstrate that sex differences in 10-day OVA-induced AHR are due to endogenous estrogen, which negatively regulates airway responsiveness in female mice. Cumulatively, the results suggest that endogenous estrogen may regulate the neurokinin 1-dependent prejunctional activation of airway smooth muscle in allergen-exposed mice.

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.

Estrogen receptor 1 polymorphisms are associated with airway hyperresponsiveness and lung function decline, particularly in female subjects with asthma

BACKGROUND

Sex hormones may contribute to the higher prevalence and severity of adult asthma in women compared with men.

OBJECTIVE

Sequence variants in the estrogen receptor alpha gene (ESR1) may alter estrogen action in asthma.

METHODS

Two hundred asthma probands and their families (n=1249) were genotyped for 5 single nucleotide polymorphisms (SNPs) in the ESR1 gene (intervening sequence 1 [IVS1]-1505A/G, IVS1-1415T/C, IVS1-397C/T, IVS1-351G/A and exon1+30T/C). Association with asthma and bronchial hyperresponsiveness (BHR) were tested. In the asthma probands, association of SNPs with BHR severity and annual FEV1 decline were determined.

RESULTS

No SNP was associated with asthma. IVS1-397 was significantly associated with the presence of BHR (P=.02) and interacted with sex; female subjects with the CT or TT genotype were at risk (P=.01). In asthma probands, all SNPs were associated with FEV1 decline. Exon1+30 CT and TT group had an excess decline of 11.6 mL/y (P=.03) and 15.7 mL/y (P=.01), respectively, compared with the CC group. Of the IVS1 polymorphisms, IVS1-351G/A showed the strongest association, with the AA group having excess decline of 16.1 mL/y (P=.01) compared with the GG group. In subanalyses by sex, these associations were significant only in female subjects.

CONCLUSION

ESR1 gene variants may affect development of BHR, particularly in female subjects. They may also lead to a more rapid lung function loss in patients with asthma, and in female subjects specifically. This may result from altered estrogen action, which affects lung development and/or airway remodeling. Further studies on ESR1 gene variations are important to understand better the origin of sex differences in asthma.

CLINICAL IMPLICATIONS

Variations in the gene encoding estrogen receptor alpha are associated with BHR and a more rapid annual lung function decline, especially in female subjects. Even though this has no diagnostic or clinical implication, it may open avenues for future sex-specific treatment in asthma.

Influence of menstrual cycle phase on pulmonary function in asthmatic athletes

The main aim of this study was to investigate whether there is a relationship between menstrual cycle phase and exercise-induced bronchoconstriction (EIB) in female athletes with mild atopic asthma. Seven eumenorrheic subjects with regular 28-day menstrual cycles were exercised to volitional exhaustion on day 5 [mid-follicular (FOL)] and day 21 [mid-luteal (LUT)] of their menstrual cycle. Pulmonary function tests were conducted pre- and post-exercise. The maximal percentage decline in post-exercise forced expiratory volume in 1 s (FEV(1)) and forced expiratory flow from 25 to 75% of forced vital capacity (FEF(25-75%)) was significantly greater (P<0.05) on day 21 (mid-LUT phase) (-17.35+/-2.32 and -26.28+/-6.04%, respectively), when salivary progesterone concentration was highest, compared to day 5 (mid-FOL phase) (-12.81+/-3.35 and -17.23+/-8.20%, respectively), when salivary progesterone concentration was lowest. The deterioration in the severity of EIB during the mid-LUT phase was accompanied by worsening asthma symptoms and increased bronchodilator use. There was a negative correlation between the percent change in pre- to post-exercise FEV(1) and salivary progesterone concentration. However, no such correlation was found between salivary estradiol and the percentage change in pre- to post-exercise FEV(1). This study has shown for the first time that menstrual cycle phase is an important determinant of the severity of EIB in female athletes with mild atopic asthma. Female asthmatic athletes may need to adjust their training and competition schedules to their menstrual cycle and to consider the potential negative effects of the LUT phase of the menstrual cycle on exercise performance.

Bronchiectasis: sex and gender considerations

Bronchiectasis in women may act more virulently. Identified gender and sex differences range from increased exposure risks to altered inflammatory responses. Common among the most well-documented examples is a differential immune response. There is sufficient evidence to suggest that chronic airway infection, most notably non-CF bronchiectasis, is a more common and more virulent disease in women. This is particularly evident in CF-and non-HIV-related environmental mycobacterial respiratory tract infections. Whether this represents an inflammatory-immune process, or environmental, anatomic, or other genetic difference remains to be detailed fully.

Estradiol in severe asthma with premenstrual worsening

OBJECTIVE

To describe the beneficial effects of estradiol in a severely asthmatic woman with premenstrual worsening of asthma.

CASE SUMMARY

A 50-year-old white woman, with a 14-year history of severe steroid-dependent asthma and monthly premenstrual worsening of asthma, was randomized to receive estradiol 2 mg or placebo for 6 days during the late luteal phase (days 23-28) of 2 successive menstrual cycles. Despite greater prednisone and inhaled beta-agonist use during the late luteal phase of the placebo cycle, the patient exhibited improved asthma symptoms, pulmonary function, and peak expiratory flows, as well as lower values for biomarkers of airway inflammation during the same time period of the estradiol cycle.

DISCUSSION

This subject's response to estradiol was in contrast to results of a randomized, controlled trial involving patients with predominantly mild asthma under excellent control. The discrepant observations for this case versus the majority of subjects in the randomized, controlled study suggest that premenstrual asthma (PMA) and a beneficial response to estradiol may be more likely in women with severe asthma.

CONCLUSIONS

The administration of estradiol during the late luteal phase of the menstrual cycle to a woman with severe asthma with PMA was associated with improved asthma symptoms, pulmonary function, and peak expiratory flows, and lower serum eosinophil protein X and urinary leukotriene E(4) biomarker concentrations. Thus, estradiol's potential role in women with severe asthma and PMA may warrant further exploration in this subgroup.