Does puberty interfere with asthma?

Sex Differences in Chronic Cough Epidemiology: The Korean Cough Study Group

BACKGROUND

Chronic cough is a common symptom encountered by healthcare practitioners. The global prevalence of chronic cough is 9.6%, with a female predominance. The aim of our study is to reveal the sex differences in prevalence and severity of chronic cough in South Korea, stratified by age and etiology.

METHODS

This study included adult patients with chronic cough who were recruited from 19 respiratory centers in South Korea. Patients completed the cough numeric rating scale (NRS) and COugh Assessment Test (COAT) questionnaire to assess the severity and multidimensional impact of cough.

RESULTS

Among the 625 patients, 419 (67.0%) were females, with a male-to-female ratio of 1:2.03. The mean age was 49.4 years, and the median duration of cough was 12 weeks. The mean NRS and COAT scores were 5.5 ± 1.8 and 9.5 ± 3.6, respectively. Female patients were older (45.3 ± 15.4 vs. 51.6 ± 15.2, P < 0.001) and more likely to have asthma/cough variant asthma (CVA) (26.7% vs. 40.8%, P = 0.001) than male patients. There was no difference in the duration or severity of cough between sexes, regardless of the cause. The male-to-female ratio was lower for upper airway cough syndrome (UACS), asthma/CVA, and gastro-esophageal reflux disease (GERD), but not for eosinophilic bronchitis (EB) or unexplained cough. The mean age of female patients was higher in UACS and asthma/CVA, but not in EB, GERD, or unexplained cough. The majority (24.2%) fell within the age category of 50s. The proportion of females with cough increased with age, with a significant rise in the 50s, 60s, and 70-89 age groups. The severity of cough decreased in the 50s, 60s, and 70-89 age groups, with no significant sex differences within the same age group.

CONCLUSION

The sex disparities in prevalence and severity of cough varied significantly depending on the age category and etiology. Understanding the specific sex-based difference could enhance comprehension of cough-related pathophysiology and treatment strategies.

Sex Hormones and Lung Inflammation

Inflammation is a characteristic marker in numerous lung disorders. Several immune cells, such as macrophages, dendritic cells, eosinophils, as well as T and B lymphocytes, synthetize and release cytokines involved in the inflammatory process. Gender differences in the incidence and severity of inflammatory lung ailments including asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis (PF), lung cancer (LC), and infectious related illnesses have been reported. Moreover, the effects of sex hormones on both androgens and estrogens, such as testosterone (TES) and 17β-estradiol (E2), driving characteristic inflammatory patterns in those lung inflammatory diseases have been investigated. In general, androgens seem to display anti-inflammatory actions, whereas estrogens produce pro-inflammatory effects. For instance, androgens regulate negatively inflammation in asthma by targeting type 2 innate lymphoid cells (ILC2s) and T-helper (Th)-2 cells to attenuate interleukin (IL)-17A-mediated responses and leukotriene (LT) biosynthesis pathway. Estrogens may promote neutrophilic inflammation in subjects with asthma and COPD. Moreover, the activation of estrogen receptors might induce tumorigenesis. In this chapter, we summarize the most recent advances in the functional roles and associated signaling pathways of inflammatory cellular responses in asthma, COPD, PF, LC, and newly occurring COVID-19 disease. We also meticulously deliberate the influence of sex steroids on the development and progress of these common and severe lung diseases.

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.

Asthma phenotypes and endotypes in childhood

Asthma is a very heterogeneous disease and since early childhood many classifications have been proposed according to phenotype and endotype. The phenotype includes the clinical features of asthma such as age of onset, triggers, comorbidities, response to treatment and evolution over time. The endotype is more difficult to define, includes the underlying immunopathological mechanisms of the disease and requires reliable biomarkers. A deep knowledge of phenotype and endotype of the patient may guide a tailored therapeutic approach. In this review the main phenotypes and endotypes of asthma acknowledged in children will be discussed.

Testosterone augments β2 adrenergic receptor genomic transcription increasing salbutamol relaxation in airway smooth muscle

Androgens in asthmatic men may be linked to asthma severity, acting via nongenomic and genomic effects. This ailment affects boys more than girls during infancy, and this proportion reverses in puberty. Plasmatic androgen concentration in young men increases at this age and might be related to lower asthma symptoms. Nongenomic actions occur in a brief period and are independent of the androgen receptor (AR), while genomic effects depend on AR, take hours-days and are modified by transcription or protein synthesis inhibitors. Guinea pig tracheas chronic incubation with testosterone (TES, 40 nM, 48 h) potentiates salbutamol-induced relaxation, an effect that was reversed by flutamide, not observed when tissues were pre-incubated with TES-bovine serum albumin (TES-BSA) nor when tissues were preincubated with TES for 15-60 min. In tracheal myocytes, TES chronic incubation increases salbutamol-induced K⁺ currents (IK⁺), an effect that was also reversed by flutamide, actinomycin D and cycloheximide and not seen with TES-BSA. The increment in IK⁺ was blocked by 4-aminopyridine and iberiotoxin, indicating that delayed rectifier K⁺ and high-conductance Ca²⁺ activated K⁺ channels were involved in the TES potentiation effect. Immunofluorescence studies showed that chronic TES augmented the β₂ adrenergic receptor (β₂-AR) expression in ASM and this finding was corroborated by q-PCR and Western blot assays. β₂-AR affinity for salbutamol after TES incubation was increased. In conclusion, chronic exposure to physiological TES concentration of the guinea pig ASM promotes β₂-AR upregulation favoring β₂ adrenergic responses and probably limiting the severity of the asthmatic exacerbations in teenage boys and men.

5α-dihydrotestosterone abrogates sex bias in asthma like features in the mouse

Androgen levels inversely correlate with the incidence, susceptibility and severity of asthma. However, whether male sex hormones such as 5α-dihydrotestosterone (DHT) have beneficial effects on asthma symptoms and/or could affect asthma susceptibility have not been investigated. DHT administration to female mice, during the sensitization phase, abrogates the sex bias in bronchial hyperreactivity. This effect correlates with inhibition of leukotriene biosynthesis in the lung. DHT significantly inhibits also other asthma-like features such as airway hyperplasia and mucus production in sensitized female mice. Conversely, DHT does not affect plasma IgE levels as well as CD3⁺CD4⁺ IL-4⁺ cell and IgE⁺c-Kit⁺ cell infiltration within the lung but prevents pulmonary mast cell activation. The in vitro study on RBL-2H3 cells confirms that DHT inhibits mast cell degranulation. In conclusion, our data demonstrate that immunomodulatory effects of DHT on mast cell activation prevent the translation of allergen sensitization into clinical manifestation of asthma.

Androgens are effective bronchodilators with anti-inflammatory properties: A potential alternative for asthma therapy

Changes in plasma androgen levels in asthmatic men may be linked to asthma severity, seemingly acting through nongenomic and genomic effects. Nongenomic effects include rapid relaxation of carbachol or antigenic challenge pre-contracted guinea pig airway smooth muscle (ASM) in vitro: testosterone (TES) blocks l-type voltage dependent Ca²⁺ channels, stored operated Ca²⁺ channels, inositol 1,4,5-trisphosphate receptors and promotes prostaglandin E₂ biosynthesis. In ASM at rest, TES lowers basal intracellular Ca²⁺ concentration and tension, maintaining a proper airway patency keeping steady smooth muscle tension and basal intracellular Ca²⁺ concentration at rest. Moreover, the bronchospasm in sensitized guinea-pigs was ablated by dehydroepiandrosterone (DHEA), a precursor of steroids, TES and its metabolites 5α- and 5β-dihydrotestosterone (DHT). On the other hand, genomic effects related to androgens' anti-inflammatory properties in asthma have been recently studied. Briefly, TES negatively regulates type 2 immune response sustained by CD4+ Th2 and group 2 innate lymphoid cells, diminishing allergic airway inflammation in males. Also, novel findings establish that TES decreases interleukin (IL)-17A protein expression produced by CD4+ Th17 cells and therefore neutrophilic airway inflammation. Clearly, DHEA, TES or its 5β-reduced metabolite that possesses minimal androgenic effect, might have potential therapeutic capacities in the treatment of severe asthma via mechanisms distinct from corticosteroid treatment.

The Association Between Female Smoking and Childhood Asthma Prevalence-A Study Based on Aggregative Data

Aims: Socioeconomic and environmental factors influence childhood asthma prevalence across the world. In-depth epidemiological research is necessary to determine the association between asthma prevalence and socio-environmental conditions, and to develop public health strategies to protect the asthmatic children against the environmental precipitators. Our research was based on aggregative data and sought to compare the asthma prevalence between children of two different age-groups across the world and to identify the association among the key socio-environmental conditions with increased childhood asthma prevalence.

Method: We included forty countries with available data on various socio-environmental conditions (2014–2015). Childhood asthma prevalence of two different age groups (6–7 and 13–14 years) were obtained from global asthma report 2014. Because of significant diversities, the selected countries were divided into two groups based on human developmental index (HDI), a well-recognized parameter to estimate the overall socioeconomic status of a country. Robust linear regression was conducted using childhood asthma prevalence as the dependent variable and female smoking prevalence, tertiary school enrollment (TSE), PM₁₀ (particulate matter ≤10 μm in diameter) and gross domestic product (GDP) as predictors.

Results: Asthma prevalence was not different between two age groups. Among all predictors, only female smoking prevalence (reflecting maternal smoking) was associated with asthma prevalence in the countries with lower socio-economic conditions (HDI), but not in the higher HDI group. The results were unchanged even after randomization.

Conclusions: Childhood asthma prevalence did not change significantly with age. Female smoking may have a positive correlation with childhood asthma prevalence in lower HDI countries.

Testosterone induces hyporesponsiveness by interfering with IP3 receptors in guinea pig airway smooth muscle

Asthma symptoms have been associated with sex steroids. During childhood, this illness seems more frequent in boys than in girls and this tendency reverts in puberty when it is more severe in women. Testosterone (TES), at supraphysiological concentrations, relaxed pre-contracted airway smooth muscle, but its effects at physiological concentrations have not been thoroughly studied. We explored this possibility in guinea pig tracheal smooth muscle. In myocytes TES (10 nM) abolished carbachol (CCh)-induced intracellular Ca2+ concentration ([Ca2+]i) increment. Ca2+ responses to ATP were partially modified by TES while histamine's were not. These results indicate that inositol 1,4,5-trisphosphate (IP3) signaling pathway might be involved. Photolysis of caged-IP3 increased [Ca2+]i and TES abolished this effect. TES diminished reactivity of the smooth muscle to CCh and this effect was non-genomic since it was unchanged by flutamide. In tracheal smooth muscle, mRNA for each IP3 receptor (ITPR) isoform was found and, by immunofluorescence, ITPR1 and ITPR3 seems to be the main isoforms observed while ITPR2 was less prominent. Comparing the amino acid sequence of ITPR1 and the sequence of the TES binding site on the androgen receptor, we found that they share a short sequence. This domain could be responsible for the TES binding to the ITPR1 and probably for its blocking effect. We conclude that TES modifies ITPR1 function in airway smooth muscle, turning this tissue less reactive to contractile agonists that act through PLCβ-IP3 signaling cascade. These results might be related to the low asthma prevalence in males from puberty to adulthood.

Sex-Specific Asthma Phenotypes, Inflammatory Patterns, and Asthma Control in a Cluster Analysis

BACKGROUND

Asthma is a heterogeneous disease with complex mechanisms and involves many risk factors and in vivo cellular molecules. It is notable that sex differences may have a potential effect on asthma phenotype.

OBJECTIVE

To identify sex-specific phenotypes and health outcomes of asthma.

METHODS

We conducted the Taiwanese Adult Asthma Cohorts study to enroll female (n = 421) and male (n = 299) adult patients with stable asthma. Eight variables were selected by a factor analysis. We further performed a 2-step sensitivity cluster analysis to classify asthma clusters. The risks of asthma-related outcomes among the clusters were assessed using simple logistic regressions.

RESULTS

Three different clusters were identified in males and females. In the female clusters, atopy/eosinophil-predominant (cluster 2), and obesity/neutrophil-predominant pattern (cluster 3) had more than a 2-fold risk of asthma exacerbations (odds ratio, 2.51; 95% CI, 1.12-5.59 and odds ratio, 2.22; 95% CI, 1.01-4.93). In the male clusters, current smoker/neutrophilic atopic cluster (cluster 5) and ex-smoker/eosinophil-predominant or mixed inflammatory pattern (cluster 6) also had a higher risk of asthma exacerbations.

CONCLUSIONS

This study identified heterogeneous characteristics between sexes. In females, the analysis showed atopy with eosinophil-predominant and obese with neutrophil-predominant inflammation. Two distinct asthma phenotypes were found in current and ex-smokers in males. Understanding asthma phenotypes and explaining the potentially biological pathways have become important.

Co-occurrence of migraine and atopy in children and adolescents: myth or a casual relationship?

PURPOSE OF REVIEW

To clarify the causal relationship between migraine and atopic disorders in children and adolescents.

RECENT FINDINGS

Migraine headache and atopic disorders including asthma are both common functional syndromes of childhood in which nature of the relationship is still debated. Attacks may induce in both disorders upon exposure to potential triggers in genetically susceptible individuals. Clinical phenotype manifests by temporary dysfunction of target tissue mediated by inflammation triggered by specific agents. Clinical features also change after puberty because of the partial effect of female sex hormones on the process. Appropriate definition of the syndrome and differentiating from other disorders are necessary not only for correct diagnosis, but also for planning of management strategies in children. Allergic rhinosinusitis needs to be differentiated from migraine even in experienced clinics. Questioning the presence of cranial autonomic symptoms is important clue in the differential diagnosis. Atopic disorder screening is particularly required in the diagnosis of migraine in childhood and adolescents. The link between both disorders of childhood seems to be far from a coincidence and some common inflammatory mechanisms are shared.

SUMMARY

On the basis of clinical features, laboratory findings and some practical clues in children, accurate diagnosis of migraine and atopic disorders are very critical for physicians, pediatricians and algologists.

Gender aspects and influence of hormones on bronchial asthma - Secondary publication and update

There is good evidence for gender-specific differences in asthma regarding all affected areas, from intra- to extra-cellular mediators to the whole organ structure und functioning of the lung. These result from complex, in parts synergistic, in other parts opposing, effects - especially of female sex hormones, and rather protective effects of male hormones against asthma, which include effects on the cellular immune system. Additionally, there are gender differences of sociocultural origin, regarding presentation, doctor's diagnosis and treatment of asthma symptoms, as well as the undertaken coping strategies concerning the female or male patient's complaints. Taking into account gender-specific differences in asthma would contribute to improved individual diagnosis and therapies.

Clinical phenotypes in asthma during childhood

Asthma is a heterogeneous disease characterized by numerous phenotypes relating to age of onset, triggers, comorbidities, severity (assessed by multiple exacerbations, lung function pattern) and finally the inflammatory cells involved in the pathophysiologic pathway. These phenotypes can vary over time in relation to changes in the principal triggers involved in the aetiology of the disease. Nevertheless, in a patient with multiple allergies and early-onset disease (defined as multiple sensitizations and allergic comorbidities), the prognosis of asthma is poor with a high risk of persistence and severity of the disease during childhood. Future research will focus on classifying phenotypes into groups based on pathophysiologic mechanisms (endotypes) and the biomarkers attached to these endotypes, which could predict prognosis and lead to targeted therapy. Currently, these biomarkers are related to inflammatory cells associated with the asthma endotype, essentially eosinophils and neutrophils (and related cytokines) attached to Th-2 and non Th-1 pathways, respectively. The most severe asthma (refractory asthma) is linked to neutrophil-derived inflammation (frequently associated with female sex, obesity and possibly disorganized airway microbiota) encountered in very young children or teenagers. Severe asthma is also linked to or a marked eosinophil inflammatory process (frequently associated with multiple atopy and, more rarely, with non-atopic hypereosinophilic asthma in children) and frequently encountered in teenagers. Severe phenotypes of asthma could also play a role in the origin of chronic obstructive pulmonary disease in adult life.

Sex discordance in asthma and wheeze prevalence in two longitudinal cohorts

Sex discordance in asthma prevalence has been previously reported, with higher prevalence in males before puberty, and in females after puberty; the adolescent "switch". However, cross-sectional studies have suggested a narrowing of this discordance in recent decades. We used a combination of cross-sectional and longitudinal modelling to examine sex differences in asthma, wheeze and longitudinal wheezing phenotypes in two UK birth cohorts, the Avon Longitudinal Study of Parents and Children (ALSPAC; born 1991-92 with data from age 0-18 years) and the Millennium Cohort Study (MCS; born 2000-02 with data from age 3-10 years). We derived measures of asthma and wheeze from questionnaires completed by mothers and cohort children. Previously-derived ALSPAC wheezing phenotype models were applied to MCS. Males had a higher prevalence of asthma at 10.7 years in ALSPAC (OR 1.45 95%CI: 1.26, 1.66 n = 7778 for current asthma) and MCS (OR 1.42 95%CI: 1.29, 1.56 n = 6726 for asthma ever) compared to females, decreasing in ALSPAC after puberty (OR 0.94 95%CI: 0.79, 1.11 n = 5023 for current asthma at 16.5 years). In longitudinal models using restricted cubic splines, males had a clear excess for asthma in the last 12 months and wheeze in the last 12 months up until 16.5 years of age in ALSPAC. Males had an increased risk of all derived longitudinal wheezing phenotypes in MCS when compared to never wheeze and no evidence of being at lower risk of late wheeze when compared to early wheeze. By comparing data in two large, contemporary cohorts we have shown the persistence of sex discordance in childhood asthma, with no evidence that the sex discordance is narrowing in recent cohorts.

Sex steroids effects on guinea pig airway smooth muscle tone and intracellular Ca2+ basal levels

Testosterone (TES), other androgens and female sex steroids induce non-genomic rapid relaxing effects in airway smooth muscle (ASM). In guinea pig ASM, basal tension was relaxed by dehydroepiandrosterone (DHEA) and TES; 17β-estradiol (E2) had a small effect. Blockers of L-type voltage dependent Ca²⁺ channel (L-VDCC, D-600) and store operated Ca²⁺ channel (SOC, 2-APB) also relaxed the basal tone. In tracheal myocytes, DHEA and TES diminished intracellular basal Ca²⁺ concentrations (_b[Ca²⁺]_i) as D-600+2-APB but to a higher extend. TES after D-600+2APB or Pyr3, a blocker of canonical transient receptor potential 3 (TRPC3), further decreased _b[Ca²⁺]_i rendering this response equal to TES alone. With indomethacin, the _b[Ca²⁺]_i decrease induced by the blockade of L-VDCC and TRPC3 was not changed by the addition of TES. PGE₂ or forskolin addition after D600+2-APB, decreased _b[Ca²⁺]_i resembling TES response. An adenylate cyclase inhibitor followed by D-600+2-APB lowered _b[Ca²⁺]_i, TES showed no further effect. Carbachol-induced [Ca²⁺]i increment was reduced by TES or DHEA. 17β-estradiol diminished KCl-induced contraction and, in tracheal myocytes, the voltage-dependent inward Ca²⁺ current.

CONCLUSION

DHEA and TES diminish ASM tone and _b[Ca²⁺]i by blocking L-VDCC and probably a constitutively active TRPC3, and by PGE₂ synthesis. E2 lowers ASM basal tone by blocking only L-VDCC.

Sex differences in child and adolescent physical morbidity: cohort study

BACKGROUND

Evidence on sex differences in physical morbidity in childhood and adolescence is based largely on studies employing single/few physical morbidity measures and different informants. We describe sex differences in a wide range of parent/carer-reported physical morbidity measures between ages 4 and 13 years to determine evidence for a generalised pattern of an emerging/increasing female 'excess'.

METHODS

Parents/carers (approximately 90% mothers) of the population-based UK ALSPAC cohort provided data on general health, physical conditions/symptoms and infections in their child approximately annually between ages 4 and 13. Logistic regression analyses determined the odds of each morbidity measure being reported in respect of females (vs males) at each age and the sex-by-age interaction, to investigate any changing sex difference with age.

RESULTS

Six measures (general health past year/month, high temperature, rash, eye and ear infections) demonstrated an emerging female 'excess', and six (earache, stomach-ache, headache, lice/scabies, cold sores, urinary infections) an increasing female 'excess'; one (breathlessness) showed a disappearing male 'excess'. Just two showed either an emerging or increasing male 'excess'. Most changes were evident during childhood (prepuberty). Six measures showed consistent female 'excesses' and four consistent male 'excesses'. Few measures showed no sex differences throughout this period of childhood/early adolescence.

CONCLUSION

Sex differences are evident for a wide range of parent-reported physical morbidity measures in childhood and early adolescence. Far more measures showed an emerging/increasing female 'excess' than an emerging/increasing male 'excess'. Further studies are required to examine whether patterns differ across sociodemographic/cultural groups, and to explain this generalised pattern.

Prenatal exposure to selenium may protect against wheezing in children by the age of 3

Introduction

It has been suggested that human in utero exposure to heavy metals such as selenium can reduce the prevalence of childhood asthma and allergic diseases. However, data on this topic are scarce. The objective of the present study was to assess the putative associations between maternal selenium level during pregnancy and the risk of asthma, wheezing, allergic rhinitis, and atopic dermatitis in children from the EDEN birth cohort by the age of 1 and 3 years.

Methods

Plasma selenium concentrations were measured in maternal blood during mid‐pregnancy (24–28 weeks of gestation) in 861 mothers. Cohort children were followed up from birth to 3 years using health questionnaires filled out by the parents for asthma, wheezing, allergic rhinitis, and atopic dermatitis. Maternal plasma selenium was related to the childhood outcomes by the age of 1 and 3 years.

Results

Our results showed a significant negative association between a high maternal plasma selenium level during pregnancy and the risk of wheezing in the child by the age of 1 and 3 years. However, maternal plasma selenium during pregnancy was not associated with the prevalence of asthma, allergic rhinitis or atopic dermatitis.

Conclusions

The results of this study suggest that the level of fetal exposure to maternal selenium could have an influence on the risk of wheezing in infancy and potentially on the risk of developing asthma later in life.

Sex hormones and systemic inflammation are modulators of the obese-asthma phenotype

BACKGROUND

Both systemic inflammation and sex hormones have been proposed as potential mediators of the obese-asthma phenotype. The aim of this study was to examine the associations between sex hormones, oral contraceptive pill (OCP) use, systemic inflammation and airway inflammation in adults with asthma.

METHODS

Obese (n = 39) and nonobese (n = 42) females and obese (n = 24) and nonobese (n = 25) males with asthma were recruited. Females were further categorized as reproductive-aged (<50 years old; n = 36) or older (>50 years old; n = 45). Thirteen (36.1%) reproductive-aged females were using the OCP. Participants had induced sputum cell counts measured and blood analysed for sex hormones and inflammatory markers.

RESULTS

Obese reproductive-aged females had higher sputum %neutrophils than nonobese reproductive-aged females (45.4 ± 24.3% vs 27.5 ± 17.5%, P = 0.016); however, there was no difference in sputum neutrophils in obese compared with nonobese males (P = 0.620) or older females (P = 0.087). Multiple linear regression analysis found testosterone and OCP use to be negative predictors of sputum %neutrophils, while C-reactive protein and IL-6 were positive predictors of sputum %neutrophils. BMI and age were not significant predictors in the multivariate model. Reproductive-aged females using the OCP had significantly lower sputum %neutrophils than those not using the OCP (23.2 ± 12.6% vs 42.1 ± 23.8%, P = 0.015).

CONCLUSIONS

This study suggests that sex hormones and systemic inflammation may be mediating the obese-asthma phenotype. The observation that OCP use was associated with lower sputum %neutrophils in reproductive-aged females warrants further investigation.

Natural progression of childhood asthma symptoms and strong influence of sex and puberty

RATIONALE

Asthma prevalence, onset, remission and relapse, and healthcare use have been intensively studied. However, asthma symptom progression through childhood and adolescence has not been well studied, in part due to the challenges in obtaining consistent and robust long-term follow-up data on a large series of subjects with asthma.

OBJECTIVES

To use the asthma diary symptom data of the Childhood Asthma Management Program placebo group (5 yr, 418 subjects, and total 564,518 records) to establish sex-specific high-resolution time courses of the natural progression of asthma symptoms through childhood and adolescence.

METHODS

We used the asthma diary symptom code as a measure of daily disease severity. Annual records of Tanner stage were used to determine the influence of puberty on severity. A data alignment technique was used to derive 13-year time courses of mean symptoms and mean Tanner stage.

MEASUREMENTS AND MAIN RESULTS

Data analyses showed three age- and sex-related phases of asthma symptom progression: Phase 1 (ages 5 and 6 yr)-greater severity in boys; Phase 2 (ages 7 to 9 yr)-no sex difference in severity; and Phase 3 (age 10-17 yr)-greater severity in girls. The continuous decline of symptoms in both sexes stops abruptly at the onset of puberty.

CONCLUSIONS

The severity of asthma symptoms varies through childhood and adolescence, and patterns differ by sex. Puberty has a strong influence on symptom progression in both sexes. Progression of symptoms is a distinct aspect of asthma epidemiology.

Sex steroid signaling: implications for lung diseases

There is increasing recognition that sex hormones (estrogen, progesterone, and testosterone) have biological and pathophysiological actions in peripheral, non-reproductive organs, including the lung. Clinically, sex differences in the incidence, morbidity and mortality of lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, lung cancer and pulmonary hypertension have been noted, although intrinsic sex differences vs. the roles of sex steroids are still not well-understood. Accordingly, it becomes important to ask the following questions: 1) Which sex steroids are involved? 2) How do they affect different components of the lung under normal circumstances? 3) How does sex steroid signaling change in or contribute to lung disease, and in this regard, are sex steroids detrimental or beneficial? As our understanding of sex steroid signaling in the lung improves, it is important to consider whether such information can be used to develop new therapeutic strategies to target lung diseases, perhaps in both sexes or in a sex-specific manner. In this review, we focus on the basics of sex steroid signaling, and the current state of knowledge regarding how they influence structure and function of specific lung components across the life span and in the context of some important lung diseases. We then summarize the potential for sex steroids as useful biomarkers and therapeutic targets in these lung diseases as a basis for future translational research in the area of gender and individualized medicine.

Androgens are bronchoactive drugs that act by relaxing airway smooth muscle and preventing bronchospasm

Changes in the androgen levels in asthmatic men may be associated with the severity of asthma. Androgens induce a nongenomic relaxation in airway smooth muscle, but the underlying mechanisms remain unclear. The aim of this study was to investigate the potential bronchorelaxing action of testosterone (TES) and its metabolites (5α- and 5β-dihydrotestosterone (DHT). A preventive effect on ovalbumin (OVA)-induced bronchospasm was observed in sensitized guinea pigs for each androgen. Androgens were studied in response to bronchoconstrictors: carbachol (CCh) and KCl in isolated trachea rings with and without epithelium from non-sensitized and sensitized animals as well as on OVA-induced contraction. Androgens concentration-dependently abolished the contraction in response to CCh, KCl, and OVA. There were significant differences in the sensitivity to the relaxation induced by each androgen. 5β-DHT was more potent for relaxing KCl-induced contraction, while TES and 5α-DHT were more potent for CCh- and OVA-induced contraction. No differences were found in preparations with and without epithelium or in the presence of a nitric oxide (NO) synthase inhibitor or an inhibitor of K(+) channels. These data indicate the absence of involvement of the epithelium-, NO- and K(+) channels-dependent pathway in androgen-induced relaxation. However, in dissociated tracheal myocytes loaded with the calcium-binding fluorescent dye Fura -2, physiological concentrations of androgens decreased the KCl-induced [Ca(2+)]i increment. 5β-DHT was the most potent at decreasing KCl-induced [Ca(2+)]i increment and preventing bronchospasm. We suggest that androgen-induced brochorelaxation was mediated via decreased Ca(2+) influx through L-type Ca(2+)channels but additional Ca(2+) entry blockade may be involved. Molecular changes in androgen structure may determine its preferential site of action.

Effects and mechanism of dehydroepiandrosterone on epithelial-mesenchymal transition in bronchial epithelial cells

BACKGROUND

Chronic persistent asthma is characterized by airway remodeling, in which epithelial-mesenchymal transition (EMT) may play a significant role. Dehydroepiandrosterone (DHEA), a steroid hormone and testosterone analog, is considered as an important immunomodulating hormone. However, its role in EMT remains unclear. We sought to investigate whether transforming growth factor-β1 (TGF-β1) stimulates human bronchial epithelial cells (16HBE-14o) to undergo EMT, and whether this transition can be abrogated by DHEA.

METHODS

The 16HBE-14o cells were stimulated with 5 ng/ml TGF-β1 for 3 days to induce EMT, with or without DHEA pretreatment, and assayed for epithelial or mesenchymal markers using Western Blot. The involvement of phosphoinositide 3-kinase (PI3K) -mediated signaling pathway was also evaluated, the epithelial cells were also incubated with pharmacological approaches (agonists and antagonists of Akt, LY294002 or IGF-1) or flutamide, the antagonist of androgen receptor. Results were analyzed using nonparametric statistical tests.

RESULTS

Our data demonstrate that treatment of 16HBE-14o cells with TGF-β1 for 3 days induced EMT as reflected by conversion to the spindle-like morphology, loss of E-cadherin, and acquisition of a-smooth muscle actin (a-SMA). Pretreatment of 16HBE-14o cells with DHEA preserved the epithelial-like morphology, restored the expression of E-cadherin, and abolished the activation of a-SMA, and this effect is a PI3K-dependent mechanism.

CONCLUSION

Our results indicate that TGF-β1 induces EMT in a PI3K-dependent manner in 16HBE-14o cells. DHEA inhibits the bronchial epithelial to mesenchymal transition via the inhibition of PI3K/Akt-dependent signal pathway stimulated by TGF-β1. Therefore, DHEA may be a useful therapy for asthma.

Nongenomic bronchodilating action elicited by dehydroepiandrosterone (DHEA) in a guinea pig asthma model

Primates secrete large amounts of the precursor steroid dehydroepiandrosterone (DHEA); in humans, its levels are low during childhood and start declining after the fourth decade. It has been postulated that the progressive decline in DHEA levels may be related with the severity of asthma associated with age. To determine whether DHEA may regulate the airway smooth muscle (ASM) activity, isolated tracheal rings with and without epithelium from male guinea pigs were isometrically recorded to characterize the response of ASM to DHEA at different concentrations on KCl- and carbachol (CCh)-induced contraction as well as on ovalbumin (OVA)-induced contraction in sensitized guinea pigs. Additionally, we used barometric plethysmography in sensitized guinea pigs in order to compare changes of the lung resistance increased by the antigen challenge to OVA in the absence and presence of different doses of DHEA. DHEA concentration-dependently abolished the contraction to KCl, CCh and OVA, and no differences were found in preparations with and without epithelium. DHEA-induced relaxation was not modified by the suppression of protein synthesis or transcription, pharmacological inhibition of nitric oxide (NO) synthase, nor by antagonist of β2-adrenergic receptors or an inhibitor of the 3β-HSD enzyme. Likewise, Ca(2+)-induced contraction in Ca(2+)-free depolarized tissues was antagonized by DHEA, and the contraction to the L-type voltage-dependent calcium channel activator (Bay K 8644) was inhibited by DHEA. Furthermore, DHEA prevented OVA-induced increases in lung resistance. These results indicate that DHEA-induced relaxation in ASM is a nongenomic (membrane) action and is not produced after its bioconversion. The data suggest that DHEA-induced relaxation is an epithelium- and NO-independent mechanism that involves a blockade of voltage-dependent calcium channels and possible non-selective cation channels.

How robust is the evidence of an emerging or increasing female excess in physical morbidity between childhood and adolescence? Results of a systematic literature review and meta-analyses

For asthma and psychological morbidity, it is well established that higher prevalence among males in childhood is replaced by higher prevalence among females by adolescence. This review investigates whether there is evidence for a similar emerging female ‘excess’ in relation to a broad range of physical morbidity measures. Establishing whether this pattern is generalised or health outcome-specific will further understandings of the aetiology of gender differences in health. Databases (Medline; Embase; CINAHL; PsycINFO; ERIC) were searched for English language studies (published 1992–2010) presenting physical morbidity prevalence data for males and females, for at least two age-bands within the age-range 4–17 years. A three-stage screening process (initial sifting; detailed inspection; extraction of full papers), was followed by study quality appraisals. Of 11 245 identified studies, 41 met the inclusion criteria. Most (n = 31) presented self-report survey data (five longitudinal, 26 cross-sectional); 10 presented routinely collected data (GP/hospital statistics). Extracted data, supplemented by additional data obtained from authors of the included studies, were used to calculate odds ratios of a female excess, or female:male incident rate ratios as appropriate. To test whether these changed with age, the values were logged and regressed on age in random effects meta-regressions. These showed strongest evidence of an emerging/increasing female excess for self-reported measures of headache, abdominal pain, tiredness, migraine and self-assessed health. Type 1 diabetes and epilepsy, based on routinely collected data, did not show a significant emerging/increasing female excess. For most physical morbidity measures reviewed, the evidence broadly points towards an emerging/increasing female excess during the transition to adolescence, although results varied by morbidity measure and study design, and suggest that this may occur at a younger age than previously thought.

Feasibility and preliminary outcomes of a school-based intervention for inner-city, ethnic minority adolescents with undiagnosed asthma

OBJECTIVE

To describe and test the feasibility of asthma self-management for adolescents with undiagnosed asthma (ASMA-Undx), an 8-week school-based intervention for urban adolescents comprised of three group and five individual coaching sessions, and academic detailing for their primary care providers (PCPs).

METHODS

Thirty high school students (mean age 15.9; 92% female; 72% Latino/a) who reported symptoms of persistent asthma, but no diagnosis were randomized to ASMA-Undx or a no-treatment control group. Interviews were conducted pre- and post-intervention.

RESULTS

All intervention students participated in the three group sessions; 64% received all five individual coaching sessions. Academic detailing telephone calls made by a pediatric pulmonologist reached 83% of the students' PCPs. Relative to controls, a significantly greater proportion of ASMA-Undx students were diagnosed (79% versus 6%, respectively), and prescribed asthma medication (57% versus 6%, respectively). Barriers to diagnosis and treatment included students' and parents' lack of knowledge about asthma.

CONCLUSION

ASMA-Undx is a feasible and promising intervention to assist urban adolescents with undiagnosed asthma obtain a diagnosis and treatment.

PRACTICE IMPLICATIONS

ASMA-Undx has the potential to reach many adolescents because it is school-based. It can serve as a model for interventions targeting other pediatric illnesses.

Gender differences in perception of dyspnea, assessment of control, and quality of life in asthma

BACKGROUND

There is limited information on the inter-relationship between gender, perception of dyspnoea and health-related quality of life (HRQoL) in asthma.

METHODS

In a cross-sectional study in an out-patient setting, 85 patients with bronchial asthma, 41 males and 44 females, underwent spirometry and were administered the following instruments to measure asthma control, HRQoL and dyspnoea : (a) Asthma control questionnaire (ACQ), (b) Asthma Quality of Life questionnaire (AQLQ), (c) Baseline dyspnoea index (BDI) questionnaire and Oxygen Cost Diagram (OCD).

RESULTS

Overall, male patients had greater airways obstruction but reported similar level of asthma control as females. Among patients with mild persistent asthma, females had a poorer level of control. The BDI and the OCD scores were significantly lower in female patients indicating greater dyspnoea and they also had a poorer quality of life especially in the symptoms and emotional domains of the AQLQ. After adjusting for the severity of airways obstruction in multivariate analysis, female gender and a poorer quality of life were independent predictors of increased perception of dyspnoea.

CONCLUSIONS

Female patients with asthma are likely to have a greater perception of dyspnoea, report a poorer control and have a poorer quality of life as compared to males. Female gender and a poorer quality of life are independent predictors of increased perception of dyspnoea in asthmatics.

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.

Do low testosterone levels contribute to the pathogenesis of asthma?

Asthma is a chronic inflammatory airway disorder that causes respiratory hypersensitivity and intermittent obstruction. Airway hyperresponsiveness to both specific and nonspecific stimuli is the hallmark of asthma. Although genetic susceptibility and airway inflammation are believed to play fundamental roles, etiology of asthma is unknown. In most cases, the treatment of asthma focuses on control of factors contributing to asthma severity and pharmacologic therapy including bronchodilator and anti-inflammatory agents. The prevalence of reported asthma is greater in prepubertal boys, with a change to a female predominance after puberty. Many epidemiological studies also suggest that women are at increased risk of developing adult-onset asthma and also suffer from more severe disease than men. This strongly suggests an important role for sex hormones in asthma. Previous articles provided us that, testosterone and/or its metabolites maintain the physiological balance of autoimmunity and protective immunity by preserving the number of regulatory cells. Testosterone is an immunosuppressant and is likely to be protective against immunological and inflammatory processes that trigger asthma. We hypothesized that the testosterone or selective androgen receptor modulators would have beneficial effects on asthma and could decrease the risk of asthmatic attacks.

The prevalence of asthma and COPD in Italy: a practice-based study

We conducted a population-based cross-sectional epidemiologic survey of asthma and COPD in an adult representative national sample using information obtained from the Health Search Database owned by the Italian College of General Practitioners. General Practitioners who had a list of patient population of 909,638 individuals (429,962 men and 479,676 women; man/woman ratio [M/WR]: 0.89) ≥ 14 years old at the end of December 2009 were selected to be representatives of the whole Italian population. Cases of asthma and COPD were identified on the basis of the ICD-9 codes. The total sample included 55,500 (6.10% of the entire population; 5.49% of men and 6.64% of women; M/WR: 0.74) subjects suffering from asthma and 25,762 (2.83% of the entire population; 3.51% of men and 2.23% of women; M/WR: 1.41) subjects suffering from COPD. The asthma/COPD ratio in general population was 2.16. The odds ratio (OR) was chosen because asthma and COPD had a prevalence less than 10%. The OR of developing asthma decreased with age both in men and women, but in the first group of age (15-34 years) it was higher in men vs. women (1.69 vs. 1.00) although it became lower than 1 from 35 years old and up in men and from 75 years old and up in women. On the contrary, the OR of developing COPD became higher than 1 from 55 years old and up both in men and in women and progressively increased with age (in the group 75-84 years, it was 6.16 in men and 4.07 in women, respectively).

Clinical implications of serum retinol-binding protein 4 in asthmatic children

Recently the prevalence of both asthma and obesity have increased substantially in many countries. The aim of this study was to evaluate the role of retinol-binding protein (RBP) 4 in childhood asthma and its association with atopy markers, pulmonary function, and bronchial hyperresponsiveness in relation to obesity. We studied 160 children between the ages 6 to 10 yr, including 122 asthmatics and 38 controls. The body mass index, pulmonary function tests, and methacholine challenge tests were measured on the same day. Total eosinophil count, serum total IgE, serum eosinophil cationic protein, and serum RBP4 were measured in all subjects. There was no difference in serum RBP4 levels between the asthmatics and the control group. In all subjects or subgroups, serum RBP4 was not associated with total eosinophil count, serum total IgE, serum eosinophil cationic protein, or PC(20). There was no relationship between serum RBP4 and pulmonary function in female asthmatics. Forced expiratory volume in 1 second/forced vital capacity (FVC) and forced expiratory flow between 25% and 75% of FVC contributed to serum RBP4 in male asthmatics. Our findings show an association between RBP4 and pulmonary function in prepubertal male asthmatics. This relationship may indirectly affect the high prevalence of childhood asthma in males.

Risk factors of adverse reactions to food in German adults

BACKGROUND

Allergic diseases have been increasing during the last decades. Previous studies suggest an impact of a variety of risk factors on the prevalence of food hypersensitivity.

OBJECTIVE

Data of a cross-sectional population-based survey were analysed to study the prevalence of food hypersensitivity in females and males adjusted for age and education.

METHODS

A population aged 18-79 years from a representative, randomly sampled survey studying 13,300 inhabitants from Germany (Berlin) was analysed. The Berlin study data were weighted with regard to age, sex, education and allergic diseases such as atopic dermatitis, rhinoconjunctivitis and asthma. Instruments for evaluation included mailed questionnaires, structured telephone interviews, physical examinations, detection of total IgE, skin prick tests and double-blind, placebo-controlled food challenge tests (DBPCFC).

RESULTS

Three thousand two hundred and twenty-seven questionnaires were evaluated. The data show a significantly higher risk of self-reported symptoms in the female group, among persons with higher education and in the age group of 18-39 years. Among individuals with clinical symptoms, females were at lower risk of having positive skin prick tests [aOR=0.32; 95% CI (0.21-0.50); P<0.01] and having a raised total IgE [aOR=0.37; 95% CI (0.24-0.56); P<0.01], but showed a higher risk of non-IgE and IgE-mediated food hypersensitivity [aOR=2.27; 95% CI (1.31-3.93); P<0.01] than males. Based on weighted data, the point prevalence of adverse reactions to food resulted in 3.3% [95% CI (2.4-4.5%)] for women and 1.8% [95% CI (1.2-2.7%)] for men after DBPCFC.

CONCLUSION

From a general population survey conducted in Germany, we determined that women are at greater risk of having symptoms of food allergy and also at greater risk of having DBPCFC-confirmed symptomatic food allergy. However, among individuals with symptoms of food allergy, men have a higher prevalence of food-specific IgE-sensitization and of raised total IgE than women.

It's all about sex: gender, lung development and lung disease

Accumulating evidence suggests that gender affects the incidence, susceptibility and severity of several lung diseases. Gender also influences lung development and physiology. Data from both human and animal studies indicate that sex hormones might contribute to disease pathogenesis or serve as protective factors, depending on the disease involved. In this review, the influence of gender and sex hormones on lung development and pathology will be discussed, with specific emphasis on pulmonary fibrosis, asthma and cancer.

Primary prevention of asthma: age and sex influence sensitivity to allergen-induced airway inflammation and contribute to asthma heterogeneity in Guinea pigs

BACKGROUND

Limiting allergen exposure in the sensitization phase has been proposed as a means of primary prevention of asthma, but its effectiveness is debated.

HYPOTHESIS

Primary prevention of asthma is more effective in limiting asthma symptoms in young guinea pigs compared with adults, whether males or females.

METHODS

The following experimental groups were used: young/young, sensitized and challenged before sexual maturity; young/adult, sensitized young and challenged after sexual maturity; adult/adult, sensitized and challenged after sexual maturity. Males and females were sensitized intraperitoneally with varying doses of ovalbumin (OVA) and challenged intratracheally with a constant OVA dose. Cellular infiltration into lung and lavage fluid as well as airway hyperresponsiveness to intravenous methacholine was determined 24 h later.

RESULTS

In unsensitized animals, density of resident inflammatory cells as well as baseline pulmonary function differed with age and sex. Maximum OVA-induced eosinophilia in females occurred at a lower sensitizing dose of OVA than in males, and the slopes of the dose-response relationship differed significantly between sexes. Young females had more pronounced increases in eosinophils compared with some adult treatment groups. The concentrations of OVA-specific antibodies were not directly related to differences in cellular infiltration. Airway hyperresponsiveness to methacholine challenge was observed in all treatment groups.

CONCLUSION

Young animals require major reductions in allergen exposure compared with adults to effectively limit airway inflammation in primary prevention. Heterogeneity of asthma symptoms seen with age and sex suggests that primary prevention by limiting allergen exposure or treatment with anti-inflammatory or bronchodilator drugs may be more effective strategies for specific age and gender populations.

Therapeutic implications of sex differences in asthma and atopy

Clear sex differences exist in asthma and atopy with a preponderance of boys before puberty. There is a reversal of this sex ratio during puberty with girls having more asthma and atopy throughout the reproductive years. Elucidating the reasons for the switch in the sex ratio should provide fresh insights into asthma and atopy with a real prospect of novel therapies for these troublesome diseases. The challenge is to match the epidemiology and physiology with the accumulating scientific knowledge on gender differences in immune responses. Hormonal changes have been implicated in the reversal of the sex ratio. Testosterone is an immunosuppressant and is likely to be protective, while female sex steroids are proinflammatory and will increase the susceptibility to atopy. Modified so as to be non-virilising/feminising, sex steroids could therefore play a useful part in modulating the immunological and inflammatory processes that underlie asthma and other allergic disorders, complementing the currently used glucocorticoid derived steroids.

Prevalence of bronchial asthma and association with environmental tobacco smoke exposure in adolescent school children in Chandigarh, north India

Prevalence of asthma and its association with environmental tobacco smoke (ETS) exposure were examined among adolescent schoolchildren in Chandigarh, India. Using a previously standardized questionnaire, data from 9090 students in the 9- to 20-year age range were analyzed. There were 4367 (48%) boys, in whom the observed prevalence of asthma was 2.6%. Among 4723 (52%) girls, asthma was present in 90 (1.9%) students. Presence of one or more respiratory symptoms was reported by 31% students. More students with asthma had either parents or other family members smoking at home as compared to nonasthmatics (41% vs. 28%, p<0.0001). The odds ratio for being asthmatic for patients exposed to ETS compared to those not exposed to ETS was 1.78 (95% confidence interval 1.33-2.31). ETS was also positively associated with prevalence of all the respiratory symptoms, with odds ratios varying between 1.6 and 2.25.

Th1 and Th2 cytokine responses to academic stress

Predominant Th2 profiles are associated with the worsening of asthma, and stress is speculated to induce a Th2 profile. The goals of this study were to examine the responses of the cytokines Th1 (IFN-gamma and IL-2) and Th2 (IL-4, IL-5, and IL-6) to a stressor and to look at the relationships between cytokine and psychological responses. Twenty-four students with and without a history of asthma completed questionnaires and gave blood samples during nonexam and exam periods. Cytokines were measured by ELISA from supernatants of stimulated mononuclear cells (MNC) and whole blood. During examinations, there were a significant decrease in IL-2 and a significant increase in IL-6 production (both cultures) and a significant decrease in IFN-gamma production (MNC cultures). Baseline IL-2 levels showed significant negative correlations with several stress and mood scores. Findings of this study indicate a down-regulation of Th1 and a selective up-regulation of Th2 cytokines during a stressful exposure.

Puberty and prognosis of asthma and bronchial hyper-reactivity

It is a commonly held view that pediatric asthma frequently abates during puberty. However, little data are available that associate the stage of puberty with the prognosis of asthma and bronchial hyper-reactivity (BHR). In this study, 155 children with active asthma at 10 years of age (60 girls [38.70%], 95 boys [61.3%]) were followed-up until they reached 14 years of age. The stage of puberty was assessed by parental questionnaire; in addition, serum 3-alpha-androstanediolglucuronide, as an endocrinological marker for peripheral androgen status, was measured in 107 subjects. Persistence of asthma was determined via questionnaire, lung function testing, and bronchial provocation (hyperventilation of cold, dry air). At 14 years of age, 73.3% of girls were reported to have had menarche and 40.8% of boys a voice change, and only 35.5% of the subjects had experienced acute asthma symptoms during the last 12 months, with an almost unchanged gender ratio (19 girls [34.5%], 36 boys [65.5%]) vs. that recorded at 10 years of age. The level of androstanediolglucuronide was higher in the children who reported puberty (mean+/-SD): 3.03+/-2.13 nmol/l vs. 1.89+/-1.26 nmol/l, p = 0.003. No statistically significant relationship was found between the reported signs of late puberty and loss of asthma or BHR. Likewise, no significant association was found between asthma persistence and the level of androstanediolglucuronide (2.39+/-1.75 nmol/l vs. 2.44+/-1.82 nmol/l, p = 0.84), or BHR and the level of androstanediolglucuronide (3.02+/-1.97 nmol/l vs. 2.28+/-1.67 nmol/l, p = 0.13), at 14 years of age, in girls or boys. At 14 years of age, no change in the gender ratio of children with active asthma had occurred. These results may indicate that the change in gender predominance of asthma through the second decade of life is not caused by increased loss of established asthma in boys between 10 and 14 years of age.

[Effects of inhaled glucocorticoids effects on the body composition in children with moderate asthma]

BACKGROUND

To assess anthropometric variables and body composition in children with moderate asthma.

SUBJECTS AND METHOD

Cross-sectional study of two homogeneous cohorts. Group 1 (study group): 84 children with moderate asthma treated with inhaled budesonide for al least 12 months; group 2 (control group): 89 healthy children. Body measurements were studied by bioelectrical impedance.

RESULTS

Males with moderate asthma showed lower values for fat-free mass and total body water. Data corrected for weight rendered no statistically significant differences.

CONCLUSIONS

Male children with moderate asthma show a lower fast-free mass.