Perimenstrual alterations in type-1/type-2 cytokine balance of normal women

Long-term space missions' effects on the human organism: what we do know and what requires further research

Space has always fascinated people. Many years have passed since the first spaceflight, and in addition to the enormous technological progress, the level of understanding of human physiology in space is also increasing. The presented paper aims to summarize the recent research findings on the influence of the space environment (microgravity, pressure differences, cosmic radiation, etc.) on the human body systems during short-term and long-term space missions. The review also presents the biggest challenges and problems that must be solved in order to extend safely the time of human stay in space. In the era of increasing engineering capabilities, plans to colonize other planets, and the growing interest in commercial space flights, the most topical issues of modern medicine seems to be understanding the effects of long-term stay in space, and finding solutions to minimize the harmful effects of the space environment on the human body.

Sex bias in lymphocytes: Implications for autoimmune diseases

Autoimmune diseases are characterized by a significant sex dimorphism, with women showing increased susceptibility to disease. This is, at least in part, due to sex-dependent differences in the immune system that are influenced by the complex interplay between sex hormones and sex chromosomes, with contribution from sociological factors, diet and gut microbiota. Sex differences are evident in the number and function of lymphocyte populations. Women mount a stronger pro-inflammatory response than males, with increased lymphocyte proliferation, activation and pro-inflammatory cytokine production, whereas men display expanded regulatory cell subsets. Ageing alters the immune landscape of men and women in differing ways, resulting in changes in autoimmune disease susceptibility. Here we review the current literature on sex differences in lymphocyte function, the factors that influence this, and the implications for autoimmune disease. We propose that improved understanding of sex bias in lymphocyte function can provide sex-specific tailoring of treatment strategies for better management of autoimmune 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.

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).

17β-Estradiol Promotes Proinflammatory and Procoagulatory Phenotype of Innate Immune Cells in the Presence of Antiphospholipid Antibodies

Antiphospholipid syndrome (APS) is the most common cause of acquired thrombophilia and recurrent spontaneous miscarriages associated with extended persistence of antiphospholipid antibodies (aPL). How circulating aPL and high-17β-estradiol (E2) environment contribute to the pregnancy complications in APS is poorly defined. Therefore, we aimed to analyse whether E2 could be responsible for the immune cell hyperactivation in aPL- positive (lupus anticoagulant, anti-cardiolipin, anti-β2-glycoprotein) in women. For this, peripheral blood mononuclear cells (PBMCs) from 14 aPL- positive and 13 aPL- negative women were cultured in the presence or absence of E2, LPS or E2+LPS and cell immunophenotype and cytokine release were analysed. In the aPL+ group, E2 presence markedly increased the percentage of NK cells positive for CD69 (p < 0.05), monocytes positive for tissue factor (TF, CD142) (p < 0.05), and B cells expressing PD-L1 (p < 0.05), as well as the elevated production of IL-1β comparing to aPL- women (p < 0.01). Regardless of aPL positivity, E2 augmented the procoagulatory response elicited by LPS in monocytes. Our findings show the ability of E2 to promote proinflammatory and procoagulatory phenotype of innate immune cells in individuals with aPL positivity. Our data highlights the significant impact of female hormones on the activation of immune cells in the presence of aPL.

17β-Estradiol affects lung function and inflammation following ozone exposure in a sex-specific manner

Inflammatory lung diseases affect men and women disproportionately, suggesting that fluctuations of circulating hormone levels mediate inflammatory responses. Studies have shown that ozone exposure contributes to lung injury and impairment of innate immunity with differential effects in men and women. Here, we hypothesized that 17β-estradiol enhances inflammation and airway hyperresponsiveness (AHR), triggered by ozone exposure, in the female lung. We performed gonadectomy and hormone treatment (17β-estradiol, 2 wk) in C57BL/6J female and male mice and exposed animals to 1 ppm of ozone or filtered air for 3 h. Twenty-four hours later, we tested lung function, inflammatory gene expression, and changes in bronchoalveolar lavage fluid (BALF). We found increased AHR and expression of inflammatory genes after ozone exposure. These changes were higher in females and were affected by gonadectomy and 17β-estradiol treatment in a sex-specific manner. Gonadectomized male mice displayed higher AHR and inflammatory gene expression than controls exposed to ozone; 17β-estradiol treatment did not affect this response. In females, ovariectomy reduced ozone-induced AHR, which was restored by 17β-estradiol treatment. Ozone exposure also increased BALF lipocalin-2, which was reduced in both male and female gonadectomized mice. Treatment with 17β-estradiol increased lipocalin-2 levels in females but lowered them in males. Gonadectomy also reduced ozone-induced expression of lung IL-6 and macrophage inflammatory protein-3 in females, which was restored by treatment with 17β-estradiol. Together, these results indicate that 17β-estradiol increases ozone-induced inflammation and AHR in females but not in males. Future studies examining diseases associated with air pollution exposure should consider the patient's sex and hormonal status.

Decreased circulating urokinase plasminogen activator receptor (uPAR) concentration in acute episodes of bipolar disorder; could it be a reflection of axonal injury?

INTRODUCTION

In recent years, the role of inflammation in the pathogenesis of Bipolar Disorder (BD) has been studied thoroughly. Urokinase-type plasminogen activator receptor (uPAR) is one of the molecules, whose concentration is of predictive value with regards to an ongoing inflammation and tissue regeneration, and it is hypothesized that it may also be altered in Bipolar Disorder. In this study, it is aimed to compare the levels of serum soluble uPAR during the manic, depressive and euthymic states of cases diagnosed with bipolar disorder, with healthy individuals.

MATERIALS AND METHODS

Forty-four BD patients at manic state (BD-m), 35 BD patients at depressive state (BD-d), 42 euthymic patients (BD-e) and 41 healthy controls (HC) who were similar with the diseased subjects regarding age and smoking status included in the study. Serum soluble uPAR levels of patients and healthy controls were measured.

RESULTS

The main finding of our study is that serum soluble uPAR levels are lower in patients diagnosed with BD either in depressive (BD-d) or in manic state (BD-m) than in BD patients in euthymic state (BD-e) or in healthy controls (HC). There was no significant difference in serum soluble uPAR concentrations between BD-m and BD-d s or between BD-e and HC with regards to serum soluble uPAR concentrations.

CONCLUSIONS

Urokinase-type plasminogen (uPA) is a molecule which is an element of uPAR system and the molecules collectively take role in inflammation, tissue regeneration and axonal regeneration within the Central Nervous System (CNS). It has previously suggested in some studies that there may be a decrease in axonal density or axonal dysfunction in CNS in bipolar individuals. Accordingly, one may say that the low concentrations of soluble uPAR measured in our bipolar patients either at depressive or at manic state is due to the diminished regulatory role of soluble uPAR on axonal regeneration in CNS of BD cases.

Partnered sexual activity moderates menstrual cycle-related changes in inflammation markers in healthy women: an exploratory observational study

OBJECTIVE

To examine differences in inflammation markers in sexually active versus abstinent women and observe changes in inflammation markers across the menstrual cycle. Cycle-related immune fluctuations may have evolved to reduce interference with conception. If so, reproductively active (i.e., sexually active) women should show the most variability in cytokine expression.

DESIGN

Participants provided serum samples at menses and ovulation (from which cytokines were assayed) and saliva samples at menses and during follicular, ovulation, and luteal phases (from which C-reactive protein [CRP] was assayed). Participants self-reported intercourse frequency during the study.

SETTING

Academic research laboratory.

PATIENT(S)

Thirty-two healthy, naturally cycling premenopausal women (sexually active, n = 15; abstinent, n = 17).

INTERVENTION(S)

Observational study.

MAIN OUTCOME MEASURE(S)

Levels of proinflammatory cytokines (interleukin-6 [IL-6], interferon γ [IFN-γ], tumor necrosis factor-α [TNF-α]), an anti-inflammatory cytokine (interleukin-4 [IL-4]), and a marker of total inflammation (CRP).

RESULT(S)

Sexually active women had higher levels of all of the immune markers measured, including both pro- and anti-inflammatory cytokines, than abstinent women. Relative to sexually active women, abstinent women had less change across the menstrual cycle in levels of CRP. Among sexually active women, higher intercourse frequency predicted greater midcycle decreases in CRP, IL-6, and IFN-γ and midcycle increases in IL-4.

CONCLUSION(S)

Sexual activity may stimulate a complex interaction between pro- and anti-inflammatory cytokines that subsequently drives midcycle declines in inflammation.

A new childhood asthma phenotype: obese with early menarche

Three concomitant phenomena occur in the later years of childhood: increases in the incidence of asthma, obesity and early menarche. This article is an overview of the current epidemiologic, basic, genetic and epigenetic evidence about this relationship. As a consequence we propose that obese girls who have an early menarche (≤ 11 years of age) constitute a new asthma phenotype in childhood. Future studies need to be carried out in order to find the best control and treatment of this new asthma phenotype.

Questions relating to premenstrual asthma

The study of asthma in fertile women needs to consider its potentially recurrent exacerbation in a specific phase of the menstrual cycle. Premenstrual asthma (PMA) refers to the deterioration of asthma in some women of fertile age during the premenstrual phase. Prevalence varies considerably according to studies (11%-47.44%) mainly because there is no standardized definition of the illness. There is a possible link between PMA and premenstrual syndrome, which is a set of physical and psychic manifestations that occur in some fertile women during the same premenstrual phase. This relation has been widely studied but there are still several unknowns. PMA etiopathogeny is not known. It involves possible causes such as hormonal variations in the premenstrual phase, the coexistence of atopy, variations during the cycle in substances related to inflammation, like LTC4 leukotrienes, catecholamines, E2 and F2α prostaglandins and certain cytokines. Also considered are psychological factors related to this phase of the menstrual cycle, a high susceptibility to infection or increased bronchial hyperreactivity prior to menstruation. Yet no factor fully explains its etiology, consequently no specific treatment exists. Researchers have investigated hormones, anti-leukotrienes, prostaglandin synthesis inhibitors, diuretics, phytoestrogens and alternative therapies, but none has been shown to be effective.

Hormonal contraceptives and asthma in women of reproductive age: analysis of data from serial national Scottish Health Surveys

OBJECTIVES

Sex steroid hormones may explain known gender-related variations in asthma prevalence and clinical manifestation. We investigated the relationship between use of hormonal contraceptives and asthma in women, and assessed evidence of biological interaction between use of hormonal contraceptives and body mass index in this relationship.

DESIGN

Population-based analysis using data from serial (i.e. 2003, 2008 and 2010) Scottish Health Surveys.

SETTING

Random samples of the Scottish general population.

PARTICIPANTS

A total of 3257 non-pregnant, 16-45-year-old women.

EXPOSURE

Current use of hormonal contraceptives.

MAIN OUTCOME MEASURES

Self-reported current physician-diagnosed asthma, current wheezing symptoms, wheezing attacks and treatment for asthma or wheeze.

RESULTS

Women comprising 30.9% (95% confidence interval 29.3-32.5) were currently using any hormonal contraceptive and current physician-diagnosed asthma was present in 6.5% (95% confidence interval 5.7-7.4). Use of any hormonal contraceptive was associated with reduced risk of current physician-diagnosed asthma (odds ratio 0.68; 95% confidence interval 0.47-0.98) and receiving ≥3 asthma care episodes (odds ratio 0.45; 95% confidence interval 0.25-0.82), but the evidence was equivocal for wheezing attacks. Use of hormonal contraceptives among overweight or obese women was non-statistically significantly associated with asthma, but there was 42-135% increased risk in overweight and obese non-contraceptive using women.

CONCLUSIONS

Use of hormonal contraceptives may reduce asthma exacerbations and number of care episodes. Overweight and obese non-contraceptive-using women may be at increased risk of asthma. Prospective studies are now needed to confirm these findings. Both oestrogen and progesterone may stimulate smooth airway muscle function and inhibit the activities of TH2 responses. Future studies should investigate these underlying mechanisms.

The effect of oral contraceptives on current wheezing in young women

BACKGROUND

Emerging evidence suggests that sex steroid hormones may influence respiratory symptoms. The existing literature about the role of oral contraceptive pill (OCP) on respiratory disease is scarce and conflicting especially during the adolescent period. In this study, we aimed to investigate the effect of OCPs on current wheezing among adolescents and young adults.

METHODS

A questionnaire was administered face-to-face to adolescents and young women by a physician. The questionnaire included ISAAC survey-comprised questions on ever wheezing, current wheezing, allergic diseases, smoking history (active or passive), and family history of allergic diseases and questions on OCP usage status. The effect of OCPs on wheezing was evaluated by logistic regression analysis.

RESULTS

A total of 487 subjects aged between 11.3 and 25.6years participated in the study and 196 (40.2%) reported that they had used OCPs. 7.4% of the participants had physician-diagnosed asthma and 10.3% of them were active smokers. It was detected that OCPs were associated with increased risk for current wheezing (odds ratio, 2.36; 95% CI, 1.25-4.47 adjusted for asthma and current smoker) and this risk was related with the usage during the past year.

CONCLUSION

Young women taking oral contraceptives had a higher rate of current wheezing, suggesting that sex steroids may be of importance for respiratory health.

Premenstrual asthma and leukotriene variations in the menstrual cycle

BACKGROUND

Several authors have reported an increase in leukotriene C4 in the premenstrual phase in women with severe premenstrual asthma, indicating that antileukotrienes could be used in treatment.

OBJECTIVE

To analyse the role of leukotrienes in premenstrual asthma.

METHODS

A questionnaire on respiratory symptoms and peak flow during one complete menstrual cycle was given to women of fertile age to define them as asthmatics who suffered from premenstrual asthma or not. Premenstrual asthma (PMA) was defined as a clinical or functional deterioration (≥20%) in the premenstrual phase compared with the preovulatory phase. Blood samples to measure leukotriene C4 were taken during the preovulatory and premenstrual phases.

RESULTS

Blood samples were taken in 62 asthmatic women, 34 of whom (54.3%) presented PMA criteria, all with a premenstrual deterioration of between 20 and 40%. There was no difference in leukotriene C4 levels between the preovulatory and premenstrual phases in the women who suffered from PMA (1.50ng/mL vs. 1.31ng/mL; p=0.32) and those who did not (1.40ng/mL vs. 1.29ng/mL; p=0.62). Neither were there any differences in leukotriene levels between women with or without PMA. The results were similar for each category of asthma severity.

CONCLUSIONS

Our data show that leukotriene C4 does not appear to be involved in the pathogenesis of premenstrual asthma, or support the use of anti-leukotrienes in the specific treatment of premenstrual asthma, at least in women with a moderate premenstrual deterioration. No differences appeared in any of the categories of asthma severity.

Smoking habit, immune suppression, oral contraceptive use, and hormone replacement therapy use and cervical carcinogenesis: a review of the literature

High-risk human papillomaviruses (HPVs) are involved in the etiopathogenesis of cervical intraepithelial neoplasia (CIN) and cervical cancer. After taking HPV into account, smoking habit appears to be the most significant environmental risk factor, and the risk of this malignancy increases significantly with intensity and duration of smoking. Women with human immunodeficiency virus (HIV) infection experience a higher incidence of CIN and invasive cervical cancer. Among HIV+ women, the highly active antiretroviral therapy increases the regression rate of CIN, but the majority of these lesions do not regress to normal. As far as oral contraceptives (OCs), a systematic review of 28 studies found that, compared with never pill users, the relative risk (RR) of cervical cancer increased with increasing duration of OC use. The results were similar for squamous cell carcinoma and adenocarcinoma, and the RRs decreased after pill discontinuation. However, by weighing risks and benefits, the World Health Organization does not recommend any change in OC practice. There is no correlation between hormone replacement therapy and cervical cancer. Experimental data have shown that estradiol and progesterone can modulate the host immune response to HPV16. Prophylactic vaccination in conjunction with cervical screening is the best prevention strategy for cervical cancer.

Premenstrual asthma and atopy markers

BACKGROUND

The frequency of atopy in women with premenstrual asthma (PMA) and its possible effect on the premenstrual exacerbation of asthma are unknown.

OBJECTIVE

To analyze the relation between atopy markers (total IgE, Phadiatop, and specific IgE) and PMA.

METHODS

Asthmatic women of reproductive age completed a questionnaire about respiratory symptoms and recorded peak flow during an entire menstrual cycle to be classified as asthmatic patients with or without PMA. Their asthma severity was graded according to the 2005 Global Initiative for Asthma scale. PMA was defined as a clinical or functional exacerbation (>or=20%) in the premenstrual phase compared with the preovulatory phase. Blood tests for several atopy markers were conducted for: total IgE and screening for aeroallergens (Phadiatop) and specific IgE.

RESULTS

Blood determinations were performed in 59 asthmatic women, of whom 31 (53%) had PMA. Twenty-six patients with PMA (84%) and 12 without PMA (43%) had total IgE values greater than 100 kU/L (P=.001). Twenty-one patients with PMA (68%) and 14 without PMA (50%) tested positive for Phadiatop (P=.17). Those who were positive for Phadiatop were also tested for specific IgE. No relation was found between specific IgE and PMA; values for ryegrass (63%), olive (60%), and Dermatophagoides pteronyssinus (54%) exceeded 0.35 kU/L.

CONCLUSIONS

PMA seems to be closely linked to total IgE levels but not to specific allergens. The atopy affects the clinical manifestations of PMA in women of reproductive age.

Progesterone and 17beta-estradiol enhance regulatory responses to human papillomavirus type 16 virus-like particles in peripheral blood mononuclear cells from healthy women

Human papillomavirus (HPV) virus-like particle (VLP) vaccines are highly effective at preventing viral infections and the development of precancerous lesions through the induction of high-titer neutralizing antibodies and strong cell-mediated immune responses. Women taking combined oral contraceptives (COCs), however, show large variabilities in the magnitudes of their antibody responses. The goal of the present study was to determine the effects of 17beta-estradiol (E2) and progesterone (P4) alone and in combination on the cellular immune response to HPV type 16 (HPV-16) VLPs in vitro. Peripheral blood mononuclear cells (PBMCs) from healthy donor women were stimulated in vitro with HPV-16 VLPs (2.5 microg/ml) in the presence of E2 and P4 administered either alone or in combination; and lymphoproliferation, cytokine production, transcription factor expression, and steroid hormone receptor expression were analyzed. HPV-16 VLPs significantly increased the levels of lymphoproliferation, proinflammatory cytokine (gamma interferon [IFN-gamma], interleukin-1beta [IL-1beta], IL-2, IL-6, IL-8, IL-12p70, IL-17, tumor necrosis factor alpha [TNF-alpha]) production, anti-inflammatory cytokine (IL-1ra, IL-10) production, and the expression of Eralpha and Erbeta but decreased the levels of Foxp3 expression and production of transforming growth factor beta (TGF-beta). Exposure of PBMCs to E2 and P4 either alone or in combination significantly decreased the levels of lymphoproliferation and production of proinflammatory cytokines (IFN-gamma, IL-12p70, TNF-alpha) but increased the levels of production of IL-10 and TGF-beta and the expression of Foxp3 in response to HPV-16 VLPs. Treatment of cells with biologically relevant concentrations of sex steroid hormones suppressed the inflammatory response and enhanced the regulatory response to HPV-16 VLPs, which may have implications for predicting the long-term efficacy of HPV vaccines, adverse events, and cross-protection among women taking COCs.

Cellular recruitment and cytokine generation in a rat model of allergic lung inflammation are differentially modulated by progesterone and estradiol

We evaluated the role of estradiol and progesterone in allergic lung inflammation. Rats were ovariectomized (Ovx) and, 7 days later, were sensitized with ovalbumin (OA) and challenged after 2 wk with inhaled OA; experiments were performed 1 day thereafter. Ovx-allergic rats showed reduced cell recruitment into the bronchoalveolar lavage (BAL) fluid relative to sham-Ovx allergic rats, as was observed in intact allergic rats treated with ICI-182,780. Estradiol increased the number of cells in the BAL of Ovx-allergic rats, whereas progesterone induced an additional reduction. Cells of BAL and bone marrow (BM) of Ovx-allergic rats released elevated amounts of IL-10 and reduced IL-1beta and TNF-alpha. BM cells of Ovx-allergic rats released increased amounts of IL-10 and lower amounts of IL-4. Estradiol treatment of Ovx-allergic rats decreased the release of IL-10 but increased that of IL-4 by BM cells. Estradiol also caused an increased release of IL-1beta and TNF-alpha by BAL cells. Progesterone significantly increased the release of IL-10, IL-1beta, and TNF-alpha by BAL cells and augmented that of IL-4 by BM cells. Degranulation of bronchial mast cells from Ovx rats was reduced after in vitro challenge, an effect reverted by estradiol but not by progesterone. We suggest that the serum estradiol-to-progesterone ratio might drive cellular recruitment, modulating the pulmonary allergy and profile of release of anti-inflammatory or inflammatory cytokines. The existence of such dual hormonal effects suggests that the hormone therapy of asthmatic postmenopausal women and of those suffering of premenstrual asthma should take into account the possibility of worsening the pulmonary conditions.

Endogenous and exogenous sex steroid hormones and asthma and wheeze in young women

BACKGROUND

Emerging evidence suggests that both endogenous and exogenous sex steroid hormones may influence the occurrence of asthma and wheeze among women.

OBJECTIVE

We investigated the associations between exogenous sex hormone (oral contraceptive [OC]) use and wheezing in young women with and without asthma history. To investigate the role of endogenous sex hormones, we examined the association between age at menarche and the development of asthma after puberty.

METHODS

We conducted a study among 905 women who had undergone menarche. Subjects were between 13 and 28 years of age and had participated in the Children's Health Study.

RESULTS

In women without asthma, OC use was associated with higher risk of current wheeze (odds ratio [OR], 1.75; 95% CI, 1.15-2.65). In contrast, OC use was associated with a markedly reduced prevalence of current wheeze in women with a history of asthma (OR, 0.18; 95% CI, 0.06-0.56; P value for interaction = .003). These associations showed significant trends with duration of OC use. Age at menarche was associated with new-onset asthma after puberty. Compared with women who had menarche after age 12 years, women with menarche before age 12 years had a 2.08-fold (95% CI, 1.05-4.12) higher risk of asthma after puberty.

CONCLUSION

Both endogenous and exogenous sex steroid hormones affect asthma and wheeze occurrences in young women.

CLINICAL IMPLICATIONS

Because women have higher asthma risk after puberty, and OC use is common among young women, clinicians may inform women with asthma about the potential effects of OC on asthma-related respiratory symptoms.

Sex hormones and the immune response in humans

In addition to their effects on sexual differentiation and reproduction, sex hormones appear to influence the immune system. This results in a sexual dimorphism in the immune response in humans: for instance, females produce more vigorous cellular and more vigorous humoral immune reactions, are more resistant to certain infections, and suffer a higher incidence of autoimmune diseases. Disease expression is also affected by the reproductive status of the female. As sex steroids--estrogens, progesterone and testosterone--differ between gender and within different reproductive stages, a lot of research has focussed on the effects of sex hormones on immune responses. Although there is also a vast literature on the effects of sex hormones on immune responses in animals, in this review we will focus on the most intriguing effects and mechanisms by which sex hormones affect different components of the immune system in humans.

Bronchiectasis: sex and gender considerations

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

The relationship of sex to asthma prevalence, health care utilization, and medications in a large managed care organization

BACKGROUND

Age-related sex differences in asthma hospitalizations and emergency department (ED) visits have been reported, but relationships of these differences to disease prevalence and outpatient management have not been defined.

OBJECTIVE

To define the relationships of sex to asthma-related health care utilization and medications, accounting for age-related differences in asthma prevalence.

METHODS

Computerized data from Southern California Kaiser-Permanente were used to identify asthmatic patients, aged 2 to 64 years, enrolled continuously during 1999 and 2000. Age-specific asthma prevalence in 1999 was calculated to identify ages of male or female predominance. Males and females were compared with regard to asthma-related health care utilization outcomes (outpatient clinic visits, ED visits, and hospitalizations) and medication use (beta-agonists, inhaled steroids, and oral steroids). Hospitalizations, ED visits, and oral steroid use were considered markers of disease severity.

RESULTS

Of the 60,694 subjects, the female-male prevalence ratio was approximately 35:65 at each age between 2 and 13 years, it was inverse (65:35) between the ages of 23 and 64 years, and prevalences were relatively similar at the ages of 14 to 22 years. In patients aged 2 to 13 years, most utilization and medication variables were significantly greater in males (P < .01). Females aged 14 to 22 years had more outpatient and ED visits and used more oral steroids than males. In patients aged 23 to 64 years, all utilization variables were significantly greater in females, except beta-agonist use and mean inhaled steroid dispensings.

CONCLUSIONS

Asthma utilization and severity appear greater in males aged 2 to 13 years, somewhat greater in females aged 14 to 22 years, and definitely greater in females aged 23 to 64 years. The mechanisms for these striking sex differences merit further investigation.

Perimenstrual asthma: a syndrome without known cause or cure

Perimenstrual worsening of asthma has been documented in 30% to 40% of asthmatic women. This increase in symptoms has been backed up by increased health care use perimenstrually, as well as by cyclic variation in peak expiratory flows. The cause of perimenstrual asthma (PMA) remains unclear. Fluctuations in hormone levels, their ratios, or both are a plausible explanation but have not been demonstrated with any consistency. Influences of sex hormones on inflammation is an area of future research, as are hormone-induced changes in smooth muscle function and beta-adrenergic receptors, prostaglandin levels, and fluid retention in the bronchial mucosa. In the light of the high prevalence of PMA, it is difficult to understand why there has been no randomized controlled trial of hormone therapy. Nevertheless, several case reports have suggested beneficial effects of estrogens, progestins, and their combination. In light of these positive case reports, well-designed, double-blind studies of sufficient sample size should now be performed to give treatment of PMA an evidence base.

Invited review: gender issues related to spaceflight: a NASA perspective

This minireview provides an overview of known and potential gender differences in physiological responses to spaceflight. The paper covers cardiovascular and exercise physiology, barophysiology and decompression sickness, renal stone risk, immunology, neurovestibular and sensorimotor function, nutrition, pharmacotherapeutics, and reproduction. Potential health and functional impacts associated with the various physiological changes during spaceflight are discussed, and areas needing additional research are highlighted. Historically, studies of physiological responses to microgravity have not been aimed at examining gender-specific differences in the astronaut population. Insufficient data exist in most of the discipline areas at this time to draw valid conclusions about gender-specific differences in astronauts, in part due to the small ratio of women to men. The only astronaut health issue for which a large enough data set exists to allow valid conclusions to be drawn about gender differences is orthostatic intolerance following shuttle missions, in which women have a significantly higher incidence of presyncope during stand tests than do men. The most common observation across disciplines is that individual differences in physiological responses within genders are usually as large as, or larger than, differences between genders. Individual characteristics usually outweigh gender differences per se.