Endogenous and exogenous sex steroid hormones in asthma and allergy in females: A systematic review and meta-analysis

Estrogen influences class-switched memory B cell frequency only in humans with two X chromosomes

Sex differences in immunity are well-documented, though mechanisms underpinning these differences remain ill-defined. Here, in a human-only ex vivo study, we demonstrate that postpubertal cisgender females have higher levels of CD19+CD27+IgD- class-switched memory B cells compared with age-matched cisgender males. This increase is only observed after puberty and before menopause, suggesting a strong influence for sex hormones. Accordingly, B cells express high levels of estrogen receptor 2 (ESR2), and class-switch-regulating genes are enriched for ESR2-binding sites. In a gender-diverse cohort, blockade of natal estrogen in transgender males (XX karyotype) reduced class-switched memory B cell frequency, while gender-affirming estradiol treatment in transgender females (XY karyotype) did not increase these levels. In postmenopausal cis-females, class-switched memory B cells were increased in those taking hormone replacement therapy (HRT) compared with those who were not. These data demonstrate that sex hormones and chromosomes work in tandem to impact immune responses, with estrogen only influencing the frequency of class-switched memory B cells in individuals with an XX chromosomal background.

Reconsidering Gender in Asthma: Is It All About Sex? A Perspective Review

Asthma is a prevalent chronic condition, affecting an estimated 260 million people worldwide, according to the 2021 Global Burden of Disease Study. This condition significantly impacts individuals of all ages. One notable finding is that asthma prevalence among adults was higher in females than males. Recent evidence suggests that these disparities in asthma prevalence and outcomes are likely due to complex interactions among hormonal, anatomical, and environmental factors, coupled with societal and behavioral influences. The interchangeable use of the terms "sex" and "gender" in the scientific literature is frequently inconsistent. Biological sex is defined by anatomical and physiological characteristics determined by genetics; "gender", on the other hand, is a more complex construct and a universally accepted definition is still lacking. This lack of clarity, coupled with potential knowledge gaps, misunderstandings, or the inherent difficulty in differentiating sex- and gender-related effects, often leads to the terms being poorly defined or used interchangeably. Such imprecise usage hinders accurate data interpretation and research progress. This paper provides a perspective review synthesizing current knowledge regarding the influence of sex and gender on asthma, specifically focusing on their impact on disease pathogenesis, clinical presentation, severity, and management strategies.

Systemic Hormonal Contraceptive Use and Rhinitis Among Adult Women: An All of Us Database Analysis

Objectives

The role of sex hormones in the pathogenesis of allergic and inflammatory conditions such as rhinitis has been receiving increased attention, with evidence supporting an inflammation-modulating role of estrogen and progesterone in the nasal mucosa. However, the specific influence of hormonal contraceptives in rhinitis has been sparsely studied. As such, we sought to investigate the association of systemic hormonal contraceptives with both allergic (AR) and nonallergic rhinitis (NAR) using a national data set of adults in the United States.

Methods

This study was conducted using data from 46,205 female participants aged 20-40 in the All of Us Research Program. Rhinitis diagnoses, systemic hormonal contraceptive use, and covariate data were extracted for all participants. These variables were included in multivariable logistic regression models assessing the association of any systemic hormonal contraceptive use with rhinitis, both AR and NAR. Separate models were conducted to examine the association of progestin-only contraceptives (POCs) and estrogen-containing contraceptives (ECCs) on the odds of rhinitis. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated.

Results

Systemic hormonal contraceptives were associated with AR (OR: 1.32; 95% CI: 1.20-1.44) but not NAR (OR: 1.20; 95% CI: 0.90-1.56) after controlling for covariates. When analyzing POCs and ECCs separately, both were associated with AR compared to those not taking any systemic hormonal contraceptives (OR: 1.29; 95% CI: 1.12-1.48 for POC, OR: 1.35; 95% CI: 1.21-1.51 for ECC) but were not significantly associated with NAR (OR: 1.04; 95% CI: 0.66-1.57 for POC, OR: 1.33; 95% CI: 0.95-1.81 for ECC).

Conclusion

Systemic hormonal contraceptive use was independently associated with AR, with no significant difference between POCs and ECCs, while not being associated with NAR. Our findings may support a hormonal role in the pathogenesis of AR, but further research is needed to establish causation and understand the underlying mechanisms linking systemic hormonal contraceptive use to AR.

Level of Evidence

3.

Obesity and Asthma: Implementing a Treatable Trait Care Model

Recognition of obesity as a treatable trait of asthma, impacting its development, clinical presentation and management, is gaining widespread acceptance. Obesity is a significant risk factor and disease modifier for asthma, complicating treatment. Epidemiological evidence highlights that obese asthma correlates with poorer disease control, increased severity and persistence, compromised lung function and reduced quality of life. Various mechanisms contribute to the physiological and clinical complexities observed in individuals with obesity and asthma. These encompass different immune responses, including Type IVb, where T helper 2 cells are pivotal and driven by cytokines like interleukins 4, 5, 9 and 13, and Type IVc, characterised by T helper 17 cells and Type 3 innate lymphoid cells producing interleukin 17, which recruits neutrophils. Additionally, Type V involves immune response dysregulation with significant activation of T helper 1, 2 and 17 responses. Finally, Type VI is recognised as metabolic-induced immune dysregulation associated with obesity. Body mass index (BMI) stands out as a biomarker of a treatable trait in asthma, readily identifiable and targetable, with significant implications for disease management. There exists a notable gap in treatment options for individuals with obese asthma, where asthma management guidelines lack specificity. For example, there is currently no evidence supporting the use of incretin mimetics to improve asthma outcomes in asthmatic individuals without Type 2 diabetes mellitus (T2DM). In this review, we advocate for integrating BMI into asthma care models by establishing clear target BMI goals, promoting sustainable weight loss via healthy dietary choices and physical activity and implementing regular reassessment and referral as necessary.

The association of infant urinary adrenal steroids with the risk of childhood asthma development

BACKGROUND

Adrenal steroids play important roles in early-life development. However, our understanding of the effects of perinatal adrenal steroids on the development of childhood asthma is incomplete.

OBJECTIVE

To evaluate the associations between early-life adrenal steroid levels and childhood asthma.

METHODS

Participants included the Infant Susceptibility to Pulmonary Infections and Asthma following Respiratory Syncytial Virus Exposure birth cohort children with untargeted urinary metabolomics data measured during early infancy (n = 264) and nasal immune mediator data measured concurrently at age 2 to 6 months (n = 76). A total of 11 adrenal steroid compounds were identified using untargeted metabolomics and 6 asthma-relevant nasal immune mediators from multiplex assays were a priori selected. Current asthma at ages 5 and 6 years was ascertained using validated questionnaires. Associations were tested using logistic and linear regression with confounders adjustment.

RESULTS

Pregnenetriol disulfate (adjusted odds ratio [aOR] = 0.20, 95% CI = 0.06-0.68) and 3a,21-dihydroxy-5b-pregnane-11,20-dione-21-glucuronide (aOR = 0.34, 95% CI = 0.14-0.75) were inversely associated with childhood asthma at 5 and 6 years after multiple testing adjustment. There was a significant interaction effect of pregnanediol-3-glucuronide by biological sex assigned at birth (aOR = 0.11, 95% CI = 0.02-0.51, for those with female sex) on childhood asthma. Pregnenetriol disulfate was inversely associated with granulocyte-macrophage colony-stimulating factor (β = -0.45, q-value = 0.05). 3a,21-dihydroxy-5b-pregnane-11,20-dione 21-glucuronide was inversely associated with interleukin [IL]-4 (β = -0.29, q-value = 0.02), IL-5 (β = -0.35, q-value = 0.006), IL-13 (β = -0.26, q-value = 0.02), granulocyte-macrophage colony-stimulating factor (β = -0.35, q-value = 0.006), and fibroblast growth factor-β (β = -0.24, q-value = 0.01) after multiple testing adjustment.

CONCLUSION

The inverse association between adrenal steroids downstream of progesterone and 17-hydroxypregnenolone and the odds of childhood asthma and nasopharyngeal type 2 immune biomarkers suggest that increased early-life adrenal steroids may suppress type 2 inflammation and protect against the development of childhood asthma.

Impact of sex on severe asthma: a cross-sectional retrospective analysis of UK primary and specialist care

INTRODUCTION

After puberty, females are more likely to develop asthma and in a more severe form than males. The associations between asthma and sex are complex with multiple intrinsic and external factors.

AIM

To evaluate the sex differences in the characteristics and treatment of patients with severe asthma (SA) in a real-world setting.

METHODS

Demographic, clinical and treatment characteristics for patients with SA in the UK Severe Asthma Registry (UKSAR) and Optimum Patient Care Research Database (OPCRD) were retrospectively analysed by sex using univariable and multivariable logistic regression analyses adjusted for year, age and hospital/practice.

RESULTS

3679 (60.9% female) patients from UKSAR and 18 369 patients (67.9% female) from OPCRD with SA were included. Females were more likely to be symptomatic with increased Asthma Control Questionnaire-6 (UKSAR adjusted OR (aOR) 1.14, 95% CI 1.09 to 1.18) and Royal College of Physicians-3 Question scores (OPCRD aOR 1.29, 95% CI 1.13 to 1.47). However, they had a higher forced expiratory volume in 1 second per cent (FEV1%) predicted (UKSAR 68.7% vs 64.8%, p<0.001) with no significant difference in peak expiratory flow. Type 2 biomarkers IgE (UKSAR 129 IU/mL vs 208 IU/mL, p<0.001) and FeNO (UKSAR 36ppb vs 46ppb, p<0.001) were lower in females with no significant difference in blood eosinophils or biological therapy. Females were less likely to be on maintenance oral corticosteroids (UKSAR aOR 0.86, 95% CI 0.75 to 0.99) but more likely to be obese (UKSAR aOR 1.67, 95% CI 145 to 1.93; OPCRD SA aOR 1.46, 95% CI 1.34 to 1.58).

CONCLUSIONS

Females had increased symptoms and were more likely to be obese despite higher FEV1% predicted and lower type 2 biomarkers with consistent and clinically important differences across both datasets.

Chinese expert consensus on the diagnosis, treatment, and management of asthma in women across life

Background

The epidemiology and severity of asthma vary by sex and age. The diagnosis, treatment, and management of asthma in female patients are quite challenging. However, there is hitherto no comprehensive and standardized guidance for female patients with asthma.

Methods

Corresponding search strategies were determined based on clinical concerns regarding female asthma. Search terms included "sex hormones and lung development", "sex hormone changes and asthma", "hormones and asthma immune response", "women, asthma", "children, asthma", "puberty, asthma", "menstruation, asthma", "pregnancy, asthma", "lactation, asthma", "menopause, asthma", "obesity, asthma", and "women, refractory, severe asthma". Literature was retrieved from PubMed/Medline, Embase, Cochrane Library, China Biology Medicine disc, China National Knowledge Infrastructure, Wanfang Data with the search date of July 30, 2022 as the last day. This consensus used the Grading of Recommendations Assessment, Development, and Evaluation to evaluate the strength of recommendation and quality of evidence.

Results

We collected basic research results and clinical evidence-based medical data and reviewed the effects of sex hormones, classical genetics, and epigenetics on the clinical presentation and treatment response of female patients with asthma under different environmental effects. Based on that, we formulated this expert consensus on the management of female asthma throughout the life cycle.

Conclusions

This expert consensus on the management of asthma in women throughout the life cycle provides diagnosis, treatment, and research reference for clinical and basic medical practitioners.

Age at menarche and asthma onset among US girls and women: findings from NHANES, 2001-2018

PURPOSE

To quantitatively estimate the association of age at menarche with the risk of childhood- and adult-onset asthma separately.

METHODS

A retrospective cohort study of 24,282 US girls and women was conducted using continuous National Health and Nutrition Examination Survey (NHANES) data from 2001 to 2018, and Cox proportional hazards regression models with censoring ages of 19 and 79 years were employed to separately estimate hazard ratios of childhood- and adult-onset asthma associated with age at menarche.

RESULTS

Each one-year increase in age at menarche was significantly associated with a 16% (hazard ratio [HR] = 0.84; 95% confidence interval [CI]: 0.77-0.91) decrease in the risk of childhood-onset asthma. Compared with age at menarche of 12-14 years, we observed a 56% (HR = 1.56; 95% CI: 1.19-2.04) increased risk of childhood-onset asthma for early menarche (age at menarche < 12 years) and a 40% (HR = 0.60; 95% CI: 0.32-1.10) decreased risk for late menarche (age at menarche ≥ 15 years). No significant association was noted between age at menarche and adult-onset asthma.

CONCLUSIONS

Early menarche may represent a risk factor for childhood-onset asthma, which indicates the need for timely and effective management of individuals with early menarche to prevent asthma.

Sex steroid hormones and allergic diseases in children: a pilot birth cohort study in the Japan Environment and Children's Study cohort

BACKGROUND

Numerous studies suggest that sex steroids might play a role in sex disparity observed in allergic diseases in adults. However, whether sex hormones influence allergic diseases in children remains unclear. The aim of the present study was to examine the association of sex steroid hormones with allergic disease in Japanese children.

METHODS

The present cross-sectional study included 145 6-year-old children participating in a pilot birth cohort study in the Japan Environment and Children's Study. Data on allergic diseases were obtained from questionnaires, and serum levels of sex steroid hormones and allergen-specific IgE were measured. Logistic regression was performed to evaluate the association of sex hormones with allergic diseases.

RESULTS

After adjusted sex, amount of body fat at 6 years, parental history of allergic disease, and exposure to tobacco smoke, serum dehydroepiandrosterone sulfate level was significantly associated with reduced odds of any allergic disease (adjusted odds ratio, 0.58; 95% confidence interval, 0.36-0.93; P = 0.024) and serum follicle-stimulating hormone level was significantly associated with increased odds of any allergic disease (adjusted odds ratio, 2.04; 95% confidence interval, 1.01-4.11, P = 0.046). Dehydroepiandrosterone sulfate level showed a significant association with number of allergic diseases.

CONCLUSIONS

The current study findings suggest that sex hormones may play an important role in the development of allergic diseases in prepubertal children.

Exogenous female sex steroid hormones and new-onset asthma in women: a matched case-control study

BACKGROUND

Evidence on the role of exogenous female sex steroid hormones in asthma development in women remains conflicting. We sought to quantify the potential causal role of hormonal contraceptives and menopausal hormone therapy (MHT) in the development of asthma in women.

METHODS

We conducted a matched case-control study based on the West Sweden Asthma Study, nested in a representative cohort of 15,003 women aged 16-75 years, with 8-year follow-up (2008-2016). Data were analyzed using Frequentist and Bayesian conditional logistic regression models.

RESULTS

We included 114 cases and 717 controls. In Frequentist analysis, the odds ratio (OR) for new-onset asthma with ever use of hormonal contraceptives was 2.13 (95% confidence interval [CI] 1.03-4.38). Subgroup analyses showed that the OR increased consistently with older baseline age. The OR for new-onset asthma with ever MHT use among menopausal women was 1.17 (95% CI 0.49-2.82). In Bayesian analysis, the ORs for ever use of hormonal contraceptives and MHT were, respectively, 1.11 (95% posterior interval [PI] 0.79-1.55) and 1.18 (95% PI 0.92-1.52). The respective probability of each OR being larger than 1 was 72.3% and 90.6%.

CONCLUSIONS

Although use of hormonal contraceptives was associated with an increased risk of asthma, this may be explained by selection of women by baseline asthma status, given the upward trend in the effect estimate with older age. This indicates that use of hormonal contraceptives may in fact decrease asthma risk in women. Use of MHT may increase asthma risk in menopausal women.

Low levels of endogenous anabolic androgenic steroids in females with severe asthma taking corticosteroids

Rationale

Patients with severe asthma are dependent upon treatment with high doses of inhaled corticosteroids (ICS) and often also oral corticosteroids (OCS). The extent of endogenous androgenic anabolic steroid (EAAS) suppression in asthma has not previously been described in detail. The objective of the present study was to measure urinary concentrations of EAAS in relation to exogenous corticosteroid exposure.

Methods

Urine collected at baseline in the U-BIOPRED (Unbiased Biomarkers for the Prediction of Respiratory Disease outcomes) study of severe adult asthmatics (SA, n=408) was analysed by quantitative mass spectrometry. Data were compared to that of mild-to-moderate asthmatics (MMA, n=70) and healthy subjects (HC, n=98) from the same study.

Measurements and main results

The concentrations of urinary endogenous steroid metabolites were substantially lower in SA than in MMA or HC. These differences were more pronounced in SA patients with detectable urinary OCS metabolites. Their dehydroepiandrosterone sulfate (DHEA-S) concentrations were <5% of those in HC, and cortisol concentrations were below the detection limit in 75% of females and 82% of males. The concentrations of EAAS in OCS-positive patients, as well as patients on high-dose ICS only, were more suppressed in females than males (p<0.05). Low levels of DHEA were associated with features of more severe disease and were more prevalent in females (p<0.05). The association between low EAAS and corticosteroid treatment was replicated in 289 of the SA patients at follow-up after 12-18 months.

Conclusion

The pronounced suppression of endogenous anabolic androgens in females might contribute to sex differences regarding the prevalence of severe asthma.

A Review of the Epigenetic Clock: Emerging Biomarkers for Asthma and Allergic Disease

DNA methylation (DNAm) is a dynamic, age-dependent epigenetic modification that can be used to study interactions between genetic and environmental factors. Environmental exposures during critical periods of growth and development may alter DNAm patterns, leading to increased susceptibility to diseases such as asthma and allergies. One method to study the role of DNAm is the epigenetic clock-an algorithm that uses DNAm levels at select age-informative Cytosine-phosphate-Guanine (CpG) dinucleotides to predict epigenetic age (EA). The difference between EA and calendar age (CA) is termed epigenetic age acceleration (EAA) and reveals information about the biological capacity of an individual. Associations between EAA and disease susceptibility have been demonstrated for a variety of age-related conditions and, more recently, phenotypes such as asthma and allergic diseases, which often begin in childhood and progress throughout the lifespan. In this review, we explore different epigenetic clocks and how they have been applied, particularly as related to childhood asthma. We delve into how in utero and early life exposures (e.g., smoking, air pollution, maternal BMI) result in methylation changes. Furthermore, we explore the potential for EAA to be used as a biomarker for asthma and allergic diseases and identify areas for further study.

Addressing sex and gender to improve asthma management

Sex (whether one is 'male' or 'female', based on biological characteristics) and gender (defined by socially constructed roles and behaviors) influence asthma diagnosis and management. For example, women generally report more severe asthma symptoms than men; men and women are exposed to different asthma-causing triggers; men tend to be more physically active than women. Furthermore, implicit, often unintended gender bias by healthcare professionals (HCPs) is widespread, and may result in delayed asthma diagnosis, which can be greater in women than men. The sex and gender of the HCP can also impact asthma management. Pregnancy, menstruation, and menopause can all affect asthma in several ways and may be associated with poor asthma control. This review provides guidance for considering sex- and gender-associated impacts on asthma diagnosis and management and offers possible approaches to support HCPs in providing personalized asthma care for all patients, regardless of their sex or gender.

Allergenicity Alleviation of Bee Pollen by Enzymatic Hydrolysis: Regulation in Mice Allergic Mediators, Metabolism, and Gut Microbiota

Bee pollen as a nutrient-rich functional food has been considered for use as an adjuvant for chronic disease therapy. However, bee pollen can trigger food-borne allergies, causing a great concern to food safety. Our previous study demonstrated that the combined use of cellulase, pectinase and papain can hydrolyze allergens into peptides and amino acids, resulting in reduced allergenicity of bee pollen based on in vitro assays. Herein, we aimed to further explore the mechanisms behind allergenicity alleviation of enzyme-treated bee pollen through a BALB/c mouse model. Results showed that the enzyme-treated bee pollen could mitigate mice scratching frequency, ameliorate histopathological injury, decrease serum IgE level, and regulate bioamine production. Moreover, enzyme-treated bee pollen can modulate metabolic pathways and gut microbiota composition in mice, further supporting the alleviatory allergenicity of enzyme-treated bee pollen. The findings could provide a foundation for further development and utilization of hypoallergenic bee pollen products.

Paediatric asthma and non-allergic comorbidities: A review of current risk and proposed mechanisms

It is increasingly recognized that children with asthma are at a higher risk of other non-allergic concurrent diseases than the non-asthma population. A plethora of recent research has reported on these comorbidities and progress has been made in understanding the mechanisms for comorbidity. The goal of this review was to assess the most recent evidence (2016-2021) on the extent of common comorbidities (obesity, depression and anxiety, neurodevelopmental disorders, sleep disorders and autoimmune diseases) and the latest mechanistic research, highlighting knowledge gaps requiring further investigation. We found that the majority of recent studies from around the world demonstrate that children with asthma are at an increased risk of having at least one of the studied comorbidities. A range of potential mechanisms were identified including common early life risk factors, common genetic factors, causal relationships, asthma medication and embryologic origins. Studies varied in their selection of population, asthma definition and outcome definitions. Next, steps in future studies should include using objective measures of asthma, such as lung function and immunological data, as well as investigating asthma phenotypes and endotypes. Larger complex genetic analyses are needed, including genome-wide association studies, gene expression-functional as well as pathway analyses or Mendelian randomization techniques; and identification of gene-environment interactions, such as epi-genetic studies or twin analyses, including omics and early life exposure data. Importantly, research should have relevance to clinical and public health translation including clinical practice, asthma management guidelines and intervention studies aimed at reducing comorbidities.

Sex Plays a Multifaceted Role in Asthma Pathogenesis

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

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.

Time-Specific Factors Influencing the Development of Asthma in Children

Susceptibility to asthma is complex and heterogeneous, as it involves both genetic and environmental insults (pre- and post-birth) acting in a critical window of development in early life. According to the Developmental Origins of Health and Disease, several factors, both harmful and protective, such as nutrition, diseases, drugs, microbiome, and stressors, interact with genotypic variation to change the capacity of the organism to successfully adapt and grow in later life. In this review, we aim to provide the latest evidence about predictive risk and protective factors for developing asthma in different stages of life, from the fetal period to adolescence, in order to develop strategic preventive and therapeutic interventions to predict and improve health later in life. Our study shows that for some risk factors, such as exposure to cigarette smoke, environmental pollutants, and family history of asthma, the evidence in favor of a strong association of those factors with the development of asthma is solid and widely shared. Similarly, the clear benefits of some protective factors were shown, providing new insights into primary prevention. On the contrary, further longitudinal studies are required, as some points in the literature remain controversial and a source of debate.

Lung Function Variation during the Estrus Cycle of Mares Affected by Severe Asthma

Simple Summary

The estrus cycle and sex hormones influence asthma development and severity in humans, but whether the same is occurring in the asthma of horses is unknown. Severe equine asthma (SEA) is characterized by breathing difficulty, even at rest, and although it can be controlled by management and medication, it remains incurable. Stabling and hay feeding are the main contributors to disease exacerbation, but other factors could possibly alter the respiratory compromise. Therefore, the objective of this study was to evaluate the effects of the estrus cycle on airway dysfunction in five mares affected by SEA by assessing the lung function during the follicular and luteal phases of the reproductive cycle. The inspiratory obstruction improved during the luteal phase and the variation in progesterone and the dominant follicle size correlated with lung function parameters, suggesting a role for sex hormones in asthma pathophysiology. This first description of the estrus cycle’s modulation of airway obstruction in horses supports further studies to uncover the effects of sex hormones in asthma in horses and humans.

Abstract

While the prevalence of asthma is higher in boys than in girls during childhood, this tendency reverses at puberty, suggesting an effect of sex hormones on the disease pathophysiology. Fluctuations of asthma severity concurring with the estrus cycle are reported in women, but this phenomenon has never been investigated in mares to date. The objective of this exploratory study was to determine whether the estrus cycle modulates airway obstruction in severe equine asthma (SEA). Five mares with SEA during exacerbation of the disease were studied. The whole breath, expiratory and inspiratory resistance, and reactance were compared during the follicular and luteal phases of the estrus cycle. The reproductive tract was evaluated by rectal palpation, ultrasound, and serum progesterone levels. The inspiratory resistance and reactance improved during the luteal phase of the estrus cycle, and variation in progesterone levels and the dominant follicle size correlated with several lung function parameters. The fluctuation of airway dysfunction during the estrus cycle is noteworthy as deterioration of the disease could perhaps be expected and prevented by horse owners and veterinarians. Further studies are required to determine if the equine species could be a suitable model to evaluate the effects of sex hormones on asthma.

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.

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.

Genetic overlap analysis of endometriosis and asthma identifies shared loci implicating sex hormones and thyroid signalling pathways

STUDY QUESTION

Is there a shared genetic or causal association of endometriosis with asthma or what biological mechanisms may underlie their potential relationships?

SUMMARY ANSWER

Our results confirm a significant but non-causal association of endometriosis with asthma implicating shared genetic susceptibility and biological pathways in the mechanisms of the disorders, and potentially, their co-occurrence.

WHAT IS KNOWN ALREADY

Some observational studies have reported a pattern of co-occurring relationship between endometriosis and asthma; however, there is conflicting evidence and the aetiology, as well as the underlying mechanisms of the relationship, remain unclear.

STUDY DESIGN, SIZE, DURATION

We applied multiple statistical genetic approaches in the analysis of well-powered, genome-wide association study (GWAS) summary data to comprehensively assess the relationship of endometriosis with asthma. Endometriosis GWAS from the International Endogene Consortium (IEC, 17 054 cases and 191 858 controls) and asthma GWAS from the United Kingdom Biobank (UKB, 26 332 cases and 375 505 controls) were analysed. Additional asthma data from the Trans-National Asthma Genetic Consortium (TAGC, 19 954 cases and 107 715 controls) were utilized for replication testing.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We assessed single-nucleotide polymorphism (SNP)-level genetic overlap and correlation between endometriosis and asthma using SNP effect concordance analysis (SECA) and linkage disequilibrium score regression analysis (LDSC) methods, respectively. GWAS meta-analysis, colocalization (GWAS-PW), gene-based and pathway-based functional enrichment analysis methods were applied, respectively, to identify SNP loci, genomic regions, genes and biological pathways shared by endometriosis and asthma. Potential causal associations between endometriosis and asthma were assessed using Mendelian randomization (MR) methods.

MAIN RESULTS AND THE ROLE OF CHANCE

SECA revealed significant concordance of SNP risk effects across the IEC endometriosis and the UKB asthma GWAS. Also, LDSC analysis found a positive and significant genetic correlation (rG = 0.16, P = 2.01 × 10-6) between the two traits. GWAS meta-analysis of the IEC endometriosis and UKB asthma GWAS identified 14 genome-wide significant (Pmeta-analysis < 5.0 × 10-8) independent loci, five of which are putatively novel. Three of these loci were consistently replicated using TAGC asthma GWAS and reinforced in colocalization and gene-based analyses. Additional shared genomic regions were identified in the colocalization analysis. MR found no evidence of a significant causal association between endometriosis and asthma. However, combining gene-based association results across the GWAS for endometriosis and asthma, we identified 17 shared genes with a genome-wide significant Fisher's combined P-value (FCPgene) <2.73 × 10-6. Additional analyses (independent gene-based analysis) replicated evidence of gene-level genetic overlap between endometriosis and asthma. Biological mechanisms including 'thyroid hormone signalling', 'abnormality of immune system physiology', 'androgen biosynthetic process' and 'brain-derived neurotrophic factor signalling pathway', among others, were significantly enriched for endometriosis and asthma in a pathway-based analysis.

LARGE SCALE DATA

The GWAS for endometriosis data were sourced from the International Endogen Consortium (IEC) and can be accessed by contacting the consortium. The GWAS data for asthma are freely available online at Lee Lab (https://www.leelabsg.org/resources) and from the Trans-National Asthma Genetic Consortium (TAGC).

LIMITATIONS, REASONS FOR CAUTION

Given we analysed GWAS datasets from mainly European populations, our results may not be generalizable to other ancestries.

WIDER IMPLICATIONS OF THE FINDINGS

This study provides novel insights into mechanisms underpinning endometriosis and asthma, and potentially their observed relationship. Findings support a co-occurring relationship of endometriosis with asthma largely due to shared genetic components. Agents targeting 'selective androgen receptor modulators' may be therapeutically relevant in both disorders. Moreover, SNPs, loci, genes and biological pathways identified in our study provide potential targets for further investigation in endometriosis and asthma.

STUDY FUNDING/COMPETING INTEREST(S)

National Health and Medical Research Council (NHMRC) of Australia (241,944, 339,462, 389,927, 389,875, 389,891, 389,892, 389,938, 443,036, 442,915, 442,981, 496,610, 496,739, 552,485, 552,498, 1,026,033 and 1,050,208), Wellcome Trust (awards 076113 and 085475) and the Lundbeck Foundation (R102-A9118 and R155-2014-1724). All researchers had full independence from the funders. Authors do not have any conflict of interest.

Population-based study of the association between asthma and exogenous female sex hormone use

OBJECTIVES

Several studies have suggested the influence of exogenous hormones on asthma, but the results are still conflicting. Moreover, there has been little associated research on Asian population. This study aimed to assess the association between use of exogenous female sex hormones and asthma in Korean women.

DESIGN

Korea National Health and Nutrition Examination Survey (KNHANES) is a nationwide programme to assess national health and nutritional status in Korea. A population-based study was conducted to analyse the relationship between self-reported asthma and exogenous hormones using the KNHANES between 2007 and 2012.

PARTICIPANTS

The study sample included 6874 premenopausal and 4912 postmenopausal women aged 30-65.

OUTCOME MEASURES

KNHANES data comprised health interviews and physical examinations. Questionnaires regarding asthma, reproductive factors and exogenous hormones were included.

RESULTS

Among postmenopausal women, 3.4% reported doctor-diagnosed asthma. Hormone replacement therapy (HRT) was associated with increased odds of doctor-diagnosed asthma (OR 1.56; 95% CI 1.04 to 2.35), while the association between HRT and wheeze in the last 1 year was not significant (OR 1.37; 95% CI 0.95 to 1.96). In premenopausal women, the prevalence of asthma was 2.3%. Use of oral contraceptives (OCs) was associated with an increased odds of doctor-diagnosed asthma (OR 1.67; 95% CI 1.01 to 2.76) and wheeze in the last 1 year (OR 1.88; 95% CI 1.31 to 2.69). These associations were dominant among non-obese women (body mass index <25 kg/m²; OR 2.36; 95% CI 1.34 to 4.17 for asthma and OR 2.15; 95% CI 1.43 to 3.23 for wheeze).

CONCLUSIONS

HRT and OCs were associated with increased asthma in postmenopausal and premenopausal women, respectively. The association between OC use and asthma was strong in non-obese premenopausal women.

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.

Menopausal hormone therapy and women's health: An umbrella review

BACKGROUND

There remains uncertainty about the impact of menopausal hormone therapy (MHT) on women's health. A systematic, comprehensive assessment of the effects on multiple outcomes is lacking. We conducted an umbrella review to comprehensively summarize evidence on the benefits and harms of MHT across diverse health outcomes.

METHODS AND FINDINGS

We searched MEDLINE, EMBASE, and 10 other databases from inception to November 26, 2017, updated on December 17, 2020, to identify systematic reviews or meta-analyses of randomized controlled trials (RCTs) and observational studies investigating effects of MHT, including estrogen-alone therapy (ET) and estrogen plus progestin therapy (EPT), in perimenopausal or postmenopausal women in all countries and settings. All health outcomes in previous systematic reviews were included, including menopausal symptoms, surrogate endpoints, biomarkers, various morbidity outcomes, and mortality. Two investigators independently extracted data and assessed methodological quality of systematic reviews using the updated 16-item AMSTAR 2 instrument. Random-effects robust variance estimation was used to combine effect estimates, and 95% prediction intervals (PIs) were calculated whenever possible. We used the term MHT to encompass ET and EPT, and results are presented for MHT for each outcome, unless otherwise indicated. Sixty systematic reviews were included, involving 102 meta-analyses of RCTs and 38 of observational studies, with 102 unique outcomes. The overall quality of included systematic reviews was moderate to poor. In meta-analyses of RCTs, MHT was beneficial for vasomotor symptoms (frequency: 9 trials, 1,104 women, risk ratio [RR] 0.43, 95% CI 0.33 to 0.57, p < 0.001; severity: 7 trials, 503 women, RR 0.29, 95% CI 0.17 to 0.50, p = 0.002) and all fracture (30 trials, 43,188 women, RR 0.72, 95% CI 0.62 to 0.84, p = 0.002, 95% PI 0.58 to 0.87), as well as vaginal atrophy (intravaginal ET), sexual function, vertebral and nonvertebral fracture, diabetes mellitus, cardiovascular mortality (ET), and colorectal cancer (EPT), but harmful for stroke (17 trials, 37,272 women, RR 1.17, 95% CI 1.05 to 1.29, p = 0.027) and venous thromboembolism (23 trials, 42,292 women, RR 1.60, 95% CI 0.99 to 2.58, p = 0.052, 95% PI 1.03 to 2.99), as well as cardiovascular disease incidence and recurrence, cerebrovascular disease, nonfatal stroke, deep vein thrombosis, gallbladder disease requiring surgery, and lung cancer mortality (EPT). In meta-analyses of observational studies, MHT was associated with decreased risks of cataract, glioma, and esophageal, gastric, and colorectal cancer, but increased risks of pulmonary embolism, cholelithiasis, asthma, meningioma, and thyroid, breast, and ovarian cancer. ET and EPT had opposite effects for endometrial cancer, endometrial hyperplasia, and Alzheimer disease. The major limitations include the inability to address the varying effects of MHT by type, dose, formulation, duration of use, route of administration, and age of initiation and to take into account the quality of individual studies included in the systematic reviews. The study protocol is publicly available on PROSPERO (CRD42017083412).

CONCLUSIONS

MHT has a complex balance of benefits and harms on multiple health outcomes. Some effects differ qualitatively between ET and EPT. The quality of available evidence is only moderate to poor.

Sex, Cells, and Asthma

There are marked sex differences in asthma prevalence and severity. Sex hormones play a central role in these sex biases and directly interact with multiple key cells involved in the pathogenesis of asthma. Here we review the known effects of estrogen, progesterone, and testosterone on airway epithelial cells, airway smooth muscle cells, the mononuclear phagocyte system, innate lymphoid cells, eosinophils, mast cells, T cells, and B cells, all in the context of asthma. Furthermore, we explore unresolved clinical questions, such as the role of sex hormones in the link between asthma and obesity.

Care of the Transgender Patient with a Pulmonary Complaint

Individuals who identify with a gender not typically associated with their sex assigned at birth are a growing population worldwide. Guidelines to help healthcare providers navigate the care of gender minorities (GMs) are often aimed at primary care providers and may be too general for subspecialists. Pulmonologists may see GM individuals for a variety of reasons, and no reference exists that contains relevant information about GM-specific care, including unique conditions to consider. A systematic review was completed to identify unique characteristics in caring for GM patients with a pulmonary complaint.

Long-term prognosis of new adult-onset asthma in obese patients

Background

Obesity has been associated with poor outcomes of asthma in cross-sectional studies, but long-term effect of obesity on asthma remains unknown.

Aims

To study the effects of obesity, found at the time of diagnosis of adult-onset asthma, on 12-year prognosis by focusing on oral corticosteroid (OCS) use and respiratory-related hospital admissions.

Methods

Patients diagnosed with adult-onset asthma (n=203) were divided into three categories based on diagnostic body mass index (BMI) (<25 kg·m⁻², 25–29.9 kg·m⁻², ≥30 kg·m⁻²) and followed for 12 years as part of the Seinäjoki Adult Asthma Study. Self-reported and dispensed OCS were assessed for the 12-year period. Data on hospital admissions were analysed based on medical records.

Results

12 years after diagnosis, 86% of the patients who were obese (BMI ≥30 kg·m⁻²) at diagnosis remained obese. During the follow-up, no difference was found in weight gain between the BMI categories. During the 12-year follow-up, patients obese at diagnosis reported more frequent use of OCS courses (46.9% versus 23.1%, p=0.028), were dispensed OCS more often (81.6% versus 56.9%, p=0.014) and at higher doses (median 1350 (interquartile range 280–3180) mg versus 600 (0–1650) mg prednisolone, p=0.010) compared to normal-weight patients. Furthermore, patients who were obese had more often one or more respiratory-related hospitalisations compared to normal-weight patients (38.8% versus 16.9%, p=0.033). In multivariate logistic regression analyses, obesity predicted OCS use and hospital admissions.

Conclusions

In adult-onset asthma, patients obese at diagnosis mostly remained obese at long-term and had more exacerbations and respiratory-related hospital admissions compared to normal-weight patients during 12-year follow-up. Weight loss should be a priority in their treatment to prevent this outcome.

Obese patients with new adult-onset asthma often remain obese in the long-term and have more exacerbations and respiratory-related hospital admissions during follow-up. High priority should be given to weight loss during treatment to prevent this outcome.https://bit.ly/2G5HtRZ

Hormone Replacement Therapy and Risk of Severe Asthma Exacerbation in Perimenopausal and Postmenopausal Women: 17-Year National Cohort Study

BACKGROUND

The impact of hormone replacement therapy (HRT) on clinical outcomes in menopausal women is uncertain.

OBJECTIVE

To investigate the association between use of HRT and severe asthma exacerbation in perimenopausal and postmenopausal women with asthma.

METHODS

We used the Optimum Patient Care Research Database, a population-based longitudinal primary care database in the United Kingdom, to construct a 17-year (January 1, 2000, to December 31, 2016) cohort of perimenopausal and postmenopausal (46-70 years, N = 31,656) women. We defined use of HRT, its subtypes, and duration of HRT use. Severe asthma exacerbation was defined as an asthma-related hospitalization, emergency department visits due to asthma, and/or prescription of oral corticosteroids. Analyses were undertaken using multilevel mixed-effects Poisson regression.

RESULTS

At baseline, 22% of women were using any HRT, 11% combined HRT, and 11% estrogen-only HRT. Previous, but not current, use of any (incidence rate ratio [IRR]: 1.24, 95% confidence interval [CI]: 1.22-1.26), combined (IRR: 1.28, 95% CI: 1.25-1.31), and estrogen-only HRT (IRR: 1.18, 95% CI: 1.14-1.21), and longer duration (1-2 years: IRR: 1.16, 95% CI: 1.13-1.19; 3-4 years: IRR: 1.43, 95% CI: 1.38-1.48; 5+ years: IRR: 1.32, 95% CI: 1.28-1.36) of HRT use were associated with increased risk of severe asthma exacerbation compared with nonuse. The risk estimates were greater among lean women (body mass index [BMI] <25 kg/m²) than among heavier women (BMI 25-29.9 kg/m² and ≥30 kg/m²) and higher among smokers than nonsmokers.

CONCLUSION

Use of HRT and subtypes, particularly previous, but not current, use and use for more than 2 years, is associated with an increased risk of severe asthma exacerbation in perimenopausal/postmenopausal women with established asthma. Lean women and smokers are at greater risk than heavier women and nonsmokers, respectively.

Trends in School Attendance for Low-Income Children with Chronic Health Conditions: Results from a Randomized Controlled Trial

BACKGROUND

In this study, we aimed to determine how school attendance changed over time for children on Medicaid with chronic health conditions enrolled in a comprehensive care coordination program called Coordinated HEalthcare for Complex Kids (CHECK).

METHODS

Medicaid beneficiaries from one managed care organization were randomized into 2 arms: CHECK program services or usual care. The final sample was 1322.

RESULTS

The mean age was 10.9 (SD = 3.7) years old and children were mostly non-Hispanic Black (62.6%) or Hispanic (34.9%). The median school attendance at baseline was 94.9% (IQR 88.9, 97.9); over one-fourth of children (28.4%) were chronically absent. School attendance was not associated with race/ethnicity, risk level, and health condition. In a model including a significant time/grade interaction, school attendance increased over time for children in pre-kindergarten (OR = 1.52, 95% CI: 1.38, 1.68; p < .001) and kindergarten to 5th grade (OR = 1.21, 95% CI: 1.17, 1.26; p < .001), and decreased for children in 6th to 8th grade (OR = 0.80, 95% CI: 0.77, 0.83; p < .001). No differences were seen in school attendance or chronic absenteeism associated with enrollment in the CHECK program.

CONCLUSIONS

School attendance improved for most of the low-income children with chronic health conditions in our cohort, except for children in middle school.

Hormone replacement therapy and asthma onset in menopausal women: National cohort study

BACKGROUND

There is uncertainty about the role of hormonal replacement therapy (HRT) in the development of asthma.

OBJECTIVE

We investigated whether use of HRT and duration of use was associated with risk of development of asthma in perimenopausal and postmenopausal women.

METHODS

We constructed a 17-year (from January 1, 2000, to December 31, 2016) open cohort of 353,173 women (aged 46-70 years) from the Optimum Patient Care Database, a longitudinal primary care database from across the United Kingdom. HRT use, subtypes, and duration of use; confounding variables; and asthma onset were defined by using the Read Clinical Classification System. We fitted multilevel Cox regression models to estimate hazard ratios (HRs) with 95% CIs.

RESULTS

During the 17-year follow-up (1,340,423 person years), 7,614 new asthma cases occurred, giving an incidence rate of 5.7 (95% CI = 5.5-5.8) per 1,000 person years. Compared with nonuse of HRT, previous use of any (HR = 0.83; 95% CI = 0.76-0.88), estrogen-only (HR = 0.89; 95% CI = 0.84-0.95), or combined estrogen and progestogen (HR = 0.82; 95% CI = 0.76-0.88) HRT was associated with a reduced risk of asthma onset. This was also the case with current use of any (HR = 0.79; 95% CI = 0.74-0.85), estrogen-only (HR = 0.80; 95% CI = 0.73-0.87), and combined estrogen and progestogen (HR = 0.78; 95% CI = 0.70-0.87) HRT. Longer duration of HRT use (1-2 years [HR = 0.93; 95% CI = 0.87-0.99]; 3-4 years [HR = 0.77; 95% CI = 0.70-0.84]; and ≥5 years [HR = 0.71; 95% CI = 0.64-0.78]) was associated with a dose-response reduced risk of asthma onset.

CONCLUSION

We found that HRT was associated with a reduced risk of development of late onset asthma in menopausal women. Further cohort studies are needed to confirm these findings.

Hormonal contraception and the risk of severe asthma exacerbation: 17-year population-based cohort study

BACKGROUND

Longitudinal studies investigating impact of exogenous sex steroids on clinical outcomes of asthma in women are lacking. We investigated the association between use of hormonal contraceptives and risk of severe asthma exacerbation in reproductive-age women with asthma.

METHODS

We used the Optimum Patient Care Research Database, a population-based, longitudinal, anonymised primary care database in the UK, to construct a 17-year (1 January 2000-31 December 2016) retrospective cohort of reproductive-age (16-45 years, n=83 084) women with asthma. Using Read codes, we defined use, subtypes and duration of use of hormonal contraceptives. Severe asthma exacerbation was defined according to recommendations of the European Respiratory Society/American Thoracic Society as asthma-related hospitalisation, accident and emergency department visits due to asthma and/or oral corticosteroid prescriptions. Analyses were done using multilevel mixed-effects Poisson regression with QR decomposition.

RESULTS

The 17-year follow-up resulted in 456 803 person-years of follow-up time. At baseline, 34% of women were using any hormonal contraceptives, 25% combined (oestrogen/progestogen) and 9% progestogen-only contraceptives. Previous (incidence rate ratio (IRR) 0.94, 95% CI 0.92 to 0.97) and current (IRR 0.96, 95% CI 0.94 to 0.98) use of any, previous (IRR 0.92, 95% CI 0.87 to 0.97) and current use of combined (IRR 0.93, 95% CI 0.91 to 0.96) and longer duration of use (3-4 years: IRR 0.94, 95% CI 0.92 to 0.97; 5+ years: IRR 0.91, 95% CI 0.89 to 0.93) of hormonal contraceptives, but not progestogen-only contraceptives, were associated with reduced risk of severe asthma exacerbation compared with non-use.

CONCLUSIONS

Use of hormonal contraceptives may reduce the risk of severe asthma exacerbation in reproductive-age women. Mechanistic studies investigating the biological basis for the influence of hormonal contraceptives on clinical outcomes of asthma in women are required.

PROTOCOL REGISTRATION NUMBER

European Union electronic Register of Post-Authorisation Studies (EUPAS22967).

Advances in understanding and reducing the burden of severe asthma in children

Severe asthma in children is rare, accounting for only a small proportion of childhood asthma. After addressing modifiable factors such as adherence to treatment, comorbidities, and adverse exposures, children whose disease is not well controlled on high doses of medication form a heterogeneous group of severe asthma phenotypes. Over the past decade, considerable advances have been made in understanding the pathophysiology of severe therapy-resistant asthma in children. However, asthma attacks and hospital admissions are frequent and mortality is still unacceptably high. Strategies to modify the natural history of asthma, prevent severe exacerbations, and prevent lung function decline are needed. Mechanistic studies have led to the development of several biologics targeting type 2 inflammation. This growing pipeline has the potential to reduce the burden of severe asthma; however, detailed assessment and characterisation of each child with seemingly severe asthma is necessary so that the most effective and appropriate management strategy can be implemented. Risk stratification, remote monitoring, and the integration of multiple data sources could help to tailor management for the individual child with severe asthma.

Serum free testosterone and asthma, asthma hospitalisations and lung function in British adults

OBJECTIVE

We examined the relation between serum-free testosterone and asthma, wheeze, asthma hospitalisations and lung function in older adults.

DESIGN

Cross-sectional study.

SETTING

UK.

PARTICIPANTS

256 419 adults aged 40 to 69 years, recruited from 2006 to 2010.

MAIN OUTCOME MEASURES

Multivariable logistic or linear regression was used for the analysis of free testosterone and physician-diagnosed asthma, current wheeze, asthma hospitalisations and lung function measures, which was adjusted for serum estradiol, smoking status and other covariates.

RESULTS

Free testosterone levels above the lowest quartile (Q1) were significantly associated with lower odds of asthma in both women (adjusted OR (aOR) for Q4 (the highest quartile) versus Q1=0.67, 95% CI=0.64 to 0.71) and men (aOR for Q4 versus Q1=0.87, 95% CI=0.82 to 0.91). Among subjects with asthma, free testosterone levels above Q1 were significantly associated with lower odds of current wheeze in women (aOR range=0.78 to 0.87), and free testosterone levels in Q4 were associated with lower odds of current wheeze in men (aOR for Q4 versus Q1=0.86, 95% CI=0.77 to 0.95). Among women with asthma, free testosterone levels in Q4 were also associated with lower odds of ≥1 asthma hospitalisation. Among men, free testosterone was positively associated with FEV₁ and FVC. Among women, free testosterone was negatively and weakly associated with FVC.

CONCLUSION

In a large study of British adults, elevated free testosterone levels are associated with lower odds of asthma and current wheeze in women and men, lower odds of asthma hospitalisations in women, and higher FEV₁ and FVC in men. DISSEMINATION TO PARTICIPANTS, AND RELATED PATIENT AND PUBLIC COMMUNITIES: The results of the study will be linked to the UK Biobank website.

Asthma in Menopausal Women: Clinical and Functional Particularities

BACKGROUND

Hormonal changes in women, especially at menopausal transition, may have significant consequences on respiratory function. This issue in asthmatic patients is more frequent, more severe, and less controlled after menopause. Tunisian data regarding this issue are limited; therefore, we assessed the clinical and functional particularities of asthma at menopausal transition.

MATERIALS AND METHODS

This descriptive-analytical study was performed for two years (2016-2017) on 82 asthmatic women followed up in the pulmonology department of Charles Nicolle hospital of Tunis. According to hormonal status, two groups were defined: G1 (menopausal patients) and G2 (non-menopausal patients). Asthma control and severity of asthma as well as other variables including gender, age, body mass index (BMI), comorbidities, allergenic status, spirometry results, health care use in the past 12 months, and prescribed medications were evaluated.

RESULTS

The mean age of patients was 50 years and half of them (60%) were menopausal women. Allergy was the most common cause of asthma (82%). A mean of 2.3 exacerbations per patient was recorded. Asthma was well controlled in 58% of patients and was moderate to severe in 80% of them. Menopausal asthmatic women had more comorbidities (p=0.006), particularly arterial hypertension (p<0.0001). Atopy was more common in non-menopausal women and they were all allergic (p=0.01). Menopausal asthmatic patients had more airflow obstruction with lower forced expiratory volume 1 and forced vital capacity (p<0.0001). They also had more exacerbations (p<0.0001) with lower PaO2 (p=0.006). Univariate analysis showed that menopause was a predictive factor of severity (p=0.01) and bad control of asthma (p=0.03). Multivariate analysis confirmed that menopause was a predictor of severity (p=0.01; OR=5.02, IC [1.36-18.46]) but not control of asthma despite the tendency to significance (p=0.07).

CONCLUSION

Our results confirm that menopause is a factor influencing the control and severity of asthma.

Associations between prenatal exposure to DDT and DDE and allergy symptoms and diagnoses in the Venda Health Examination of Mothers, Babies and their Environment (VHEMBE), South Africa

Dichlorodiphenyl trichloroethane (DDT) is an organochlorine insecticide that is banned internationally except for use as part of Indoor Residual Spraying (IRS) programs to control malaria. Although animal studies show that DDT and its breakdown product dichlorodiphenyl dichloroethylene (DDE) affect the immune system and may cause allergies, no studies have examined this question in populations where IRS is conducted. The aim of our study was to investigate whether prenatal exposure to DDT and DDE is associated with allergy symptoms and diagnose among South African children living in an area where IRS is conducted. To accomplish this aim, we used data from the Venda Health Examination of Mothers, Babies and their Environment (VHEMBE), an ongoing birth cohort study of 752 children born between 2012 and 2013 in the rural Vhembe district of Limpopo, South Africa. We measured maternal peripartum serum concentrations of DDT and DDE, and administered a questionnaire to the caregivers of 658 children aged 3.5 years to collect information on allergy symptoms and diagnoses as well as potential confounders using validated instruments. Using multiple logistic regression models, we found positive associations between DDT and DDE serum concentrations and most of the allergy symptoms and diagnoses. Maternal DDT (Odds Ratio [OR] = 1.5 per 10-fold increase, 95% Confidence interval, CI = 1.0, 2.3) and DDE (OR = 1.4, 95% CI = 0.8, 2.4) serum concentrations were most strongly associated with caregiver report of wheezing or whistling in the chest. Concentrations of DDT and/or DDE were also associated with increased odds of children's chests sounding wheezy during or after exercise, itchy rashes coming and going for at least six months, diagnosis of food allergy, and diagnosis of dust or dust mites allergy but confidence intervals crossed the null. Results suggest that prenatal exposure to DDT, and possibly DDE, is associated with elevated odds of wheezing among children from an IRS area.

Hormonal contraceptives and onset of asthma in reproductive-age women: Population-based cohort study

BACKGROUND

Despite well-described sex differences in asthma incidence, there remains uncertainty about the role of female sex hormones in the development of asthma.

OBJECTIVE

We sought to investigate whether hormonal contraceptive use, its subtypes, and duration of use were associated with new-onset asthma in reproductive-age women.

METHODS

Using the Optimum Patient Care Research Database, a UK national primary care database, we constructed an open cohort of 16- to 45-year-old women (N = 564,896) followed for up to 17 years (ie, January 1, 2000, to December 31, 2016). We fitted multilevel Cox regression models to analyze the data.

RESULTS

At baseline, 26% of women were using any hormonal contraceptives. During follow-up (3,597,146 person-years), 25,288 women developed asthma, an incidence rate of 7.0 (95% CI, 6.9-7.1) per 1000 person-years. Compared with nonuse, previous use of any hormonal contraceptives (hazard ratio [HR], 0.70; 95% CI, 0.68-0.72), combined (HR, 0.70; 95% CI, 0.68-0.72), and progestogen-only therapy (HR, 0.70; 95% CI, 0.67-0.74) was associated with reduced risk of new-onset asthma. For current use, the estimates were as follows: any (HR, 0.63; 95% CI, 0.61-0.65), combined (HR, 0.65; 95% CI, 0.62-0.67), and progestogen-only therapy (HR, 0.59; 95% CI, 0.56-0.62). Longer duration of use (1-2 years: HR, 0.83; 95% CI, 0.81-0.86; 3-4 years: HR, 0.64; 95% CI, 0.61-0.67; 5+ years: HR, 0.46; 95% CI, 0.44-0.49) was associated with a lower risk of asthma onset than nonuse.

CONCLUSIONS

Hormonal contraceptive use was associated with reduced risk of new-onset asthma in women of reproductive age. Mechanistic investigations to uncover the biological processes for these observations are required. Clinical trials investigating the safety and effectiveness of hormonal contraceptives for primary prevention of asthma will be helpful to confirm these results.

Timing of Maternal Asthma Diagnosis in Relation to Adverse Perinatal Outcomes

BACKGROUND

It is unclear if asthma diagnosed during pregnancy puts the fetus at a higher risk of poor perinatal outcomes than pre-existing asthma.

OBJECTIVE

To assess if the risks of prematurity, major malformations, and small-for-gestational age (SGA) are higher in women with asthma diagnosed during versus pre-pregnancy.

METHODS

We retrospectively analyzed a cohort of pregnant women aged ≥15 years with and without incident asthma, constructed from health administrative databases. Follow-up began 24 months before pregnancy onset (cohort entry) and ended at delivery. Incident asthma was defined as a first diagnosis among those without asthma in the 8 years before cohort entry. Time was classified into pre-pregnancy and each trimester until delivery. We fit inverse probability weighted Poisson models to estimate marginal relative risks (RRs) for prematurity (delivery <37th week), major malformations, and SGA (birth weight <10th percentile) comparing women with and without asthma, assessing the asthma timing of diagnosis interaction term via a Wald test.

RESULTS

In a cohort of 122,880 deliveries, the increased risk of prematurity, but not SGA, due to incident asthma was higher in those diagnosed during the second (RR, 1.34; 95% confidence interval [CI], 1.08-1.65; Wald P = .05) and third (RR, 1.93; 95% CI, 1.62-2.29; Wald P < .01) trimesters relative to pre-pregnancy (RR, 1.06; 95% CI, 0.98-1.15). A trend toward an increased risk of major malformations was observed in those diagnosed during the first trimester (RR, 1.18; 95% CI, 0.94-1.49; Wald P = .15) than pre-pregnancy (RR, 0.99; 95% CI, 0.92-1.07).

CONCLUSIONS

Asthma diagnosed during, versus before, pregnancy was associated with a greater prematurity risk, suggesting an important role of preconception and prenatal screening.

Sex Steroid Hormones and Asthma in a Nationwide Study of U.S. Adults

Rationale: Women have a higher burden of asthma than men. Although sex hormones may explain sex differences in asthma, their role is unclear.Objectives: To examine sex hormone levels and asthma in adults.Methods: Cross-sectional study of serum levels of free testosterone and estradiol and current asthma in 7,615 adults (3,953 men and 3,662 women) aged 18-79 years who participated in the 2013-2014 and 2015-2016 U.S. National Health and Nutrition Examination Survey. Logistic regression was used for the multivariable analysis of sex hormones and current asthma, which was conducted separately in women and men.Measurements and Main Results: Free testosterone levels in the fourth quartile were associated with lower odds of current asthma in women (odds ratio [OR] for the fourth quartile [Q4] vs. Q1, 0.56; 95% confidence interval [CI], 0.39-0.80). Given an interaction between obesity and sex hormones on current asthma, we stratified the analysis by obesity. In this analysis, elevated free testosterone (OR for Q4 vs. Q1, 0.59; 95% CI, 0.37-0.91) and estradiol (OR for Q4 vs. Q1, 0.43; 95% CI, 0.23-0.78) levels were associated with reduced odds of current asthma in obese women, and an elevated serum estradiol was associated with lower odds of current asthma in nonobese men (OR for Q4 vs. Q1, 0.44; 95% CI, 0.21-0.90).Conclusions: Our findings suggest that sex hormones play a role in known sex differences in asthma in adults. Moreover, our results suggest that obesity modifies the effects of sex hormones on asthma in adults.

Asthma and/or hay fever as predictors of fertility/impaired fecundity in U.S. women: National Survey of Family Growth

This study addresses whether asthma and/or hay fever predict fertility and impaired fecundity. The lifetime number of pregnancies (fertility) and spontaneous pregnancy losses (impaired fecundity) in 10,847 women representative of the U.S. population 15 to 44 years of age with histories of diagnosed asthma and/or hay fever are analyzed in the 1995 National Survey of Family Growth using multivariable Poisson regression with multiple covariates and adjustments for complex sampling. Smokers have significantly increased fertility compared to nonsmokers. Smokers with asthma only have significantly increased fertility compared to other smokers. Higher fertility is associated with impaired fecundity (ectopic pregnancy, miscarriage, stillbirth). Women with asthma (with and without hay fever) have significantly higher pregnancy losses than women without asthma. With increasing number of pregnancies, smokers have increased pregnancy losses compared to nonsmokers. Smokers, especially those with asthma only, have increased fertility and require special attention as to their family planning needs, reproductive health, and smoking cessation. Women with asthma, regardless of number of pregnancies, and smokers with higher numbers of pregnancies have high risk pregnancies that require optimal asthma/medical management prenatally and throughout pregnancy. Whether a proinflammatory asthma endotype underlies both the increased fertility and impaired fecundity associated with age and smoking is discussed.

Novel Insights on Sex-Related Differences in Asthma

PURPOSE OF REVIEW

Asthma, a common respiratory disease that affects about 10% of the US population, represents a significant public health issue. In the last decade, cumulative evidence has demonstrated sex disparities in asthma, including significant differences in epidemiology, clinical presentation, response to therapies, and health outcomes. Understanding sex-related differences in asthma enables clinicians to provide personalized asthma care and improve asthma outcome.

RECENT FINDINGS

Recent studies on sex-related differences in asthma inform us on mechanism underlying asthma pathogenesis across all age groups. Sex hormones directly modulate immune pathways crucial in asthma pathogenesis and affect individual's response to environmental triggers and medications, such as leukokotriene inhibitors. Not surprisingly, the use of external sex hormone supplementations appears to modulate asthma risk. Identification of sex-specific asthma risk loci through genome-wide association studies also provides supporting evidence on sex-related differences in asthma. There is an interaction between sex and obesity, an interaction that could place females at higher risk for systemic inflammation and, consequently, asthma. In this article, we review epidemiological and clinical studies on sex-related differences in asthma, with a special focus on the role of sex hormones, including hormonal therapies and the asthma-obesity interaction.

Advances in asthma, asthma-COPD overlap, and related biologics in 2018

Over the past year, numerous important advances in our understanding of multiple aspects of asthma, ranging from disease pathogenesis to epidemiology to therapeutics, have been reported. This review is a compilation of highlights from articles published largely in the Journal of Allergy and Clinical Immunology and supplemented by articles published elsewhere that have substantially advanced the fields of asthma, chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap and biologic therapies for these disorders. The intention of this article is not to provide a comprehensive review but rather to focus on several areas that have developed quickly and/or received extensive attention from our readers.

Factors related to changes in the asthma male: female ratio by age in 403 Mexican counties

BACKGROUND

Asthma is more frequent in males during childhood and in females after adolescence, which has been attributed to changes in sexual hormones levels.

OBJECTIVE

We explored changes of the asthma male: female ratio (AMFR) by age group in a large population (nationwide), and its ecological association (at county level) with some medical, geographical, or sociodemographic factors.

METHODS

Registries of the largest medical institution in Mexico (∼37.5 million subjects assigned to a family physician) were analyzed and the AMFR calculated using asthma incidences.

RESULTS

In boys, asthma incidence peaked at 0 to 4 years and progressively decreased, reaching a plateau in adulthood. In girls, asthma incidence showed a bimodal pattern, with maximal rates at 0 to 4 years old, and again at 50 to 54 years old. In the ecological analysis performed in more than 400 counties, the AMFR in adults (≥15 years old) inversely correlated with population density (r = -0.256) and altitude (r = -0.144), and directly correlated with acute respiratory tract infections (ARTI, r = 0.215), diabetes (r = 0.186), marginalization (r = 0.179), pneumonias (r = 0.166), and mean maximal temperature (r = 0.142), all with P < .01. In the multiple linear regression, only population density (P < .001) and ARTI (P = .006) remained statistically significant in the final model.

CONCLUSION

Asthma incidence in males and females did not match the expected sexual hormones variations, and other factors such as population density and ARTI also influenced the AMFR. These findings challenge the traditional belief that sexual hormones are major determinants of the AMFR.

A review on the pathophysiology of asthma remission

Asthma is a chronic respiratory condition, which is highly prevalent worldwide. Although no cure is currently available, it is well recognized that some asthma patients can spontaneously enter remission of the disease later in life. Asthma remission is characterized by absence of symptoms and lack of asthma-medication use. Subjects in asthma remission can be divided into two groups: those in clinical remission and those in complete remission. In clinical asthma remission, subjects still have a degree of lung functional impairment or bronchial hyperresponsiveness, while in complete asthma remission, these features are no longer present. Over longer periods, the latter group is less likely to relapse. This remission group is of great scientific interest due to the higher potential to find biomarkers or biological pathways that elicit or are associated with asthma remission. Despite the fact that the definition of asthma remission varies between studies, some factors are reproducibly observed to be associated with remitted asthma. Among these are lower levels of inflammatory markers, which are lowest in complete remission. Additionally, in both groups some degree of airway remodeling is present. Still, the pathological disease state of asthma remission has been poorly investigated. Future research should focus on at least two aspects: further characterisation of the small airways and airway walls in order to determine histologically true remission, and more thorough biological pathway analyses to explore triggers that elicit this phenomenon. Ultimately, this will result in pharmacological targets that provide the potential to steer the course of asthma towards remission.

Severe Asthma-Perspectives From Adult and Pediatric Pulmonology

Both adults and children with severe asthma represent a small proportion of the asthma population; however, they consume disproportionate resources. For both groups it is important to confirm the diagnosis of severe asthma and ensure that modifiable factors such as adherence have, as far as possible, been addressed. Most children can be controlled on inhaled corticosteroids and long term oral corticosteroid use is rare, in contrast to adults where steroid related morbidity accounts for a large proportion of the costs of severe asthma. Atopic sensitization is very common in children with severe asthma as are other atopic conditions such as allergic rhinitis and hay fever which can impact on asthma control. In adults, the role of allergic driven disease, even in those with co-existent evidence of sensitization, is unclear. There is currently an exciting pipeline of novel biologicals, particularly directed at Type 2 inflammation, which afford the possibility of improved asthma control and reduced treatment side effects for people with asthma. However, not all drugs will work for all patients and accurate phenotyping is essential. In adults the terms T2 high and T2 low asthma have been coined to describe groups of patients based on the presence/absence of eosinophilic inflammation and T-helper 2 (TH₂) cytokines. Bronchoscopic studies in children with severe asthma have demonstrated that these children are predominantly eosinophilic but the cytokine patterns do not fit the T2 high paradigm suggesting other steroid resistant pathways are driving the eosinophilic inflammation. It remains to be seen whether treatments developed for adult severe asthma will be effective in children and which biomarkers will predict response.