Immune, inflammatory and infectious consequences of estrogen in women with cystic fibrosis

Sex differences in outcomes of people with cystic fibrosis treated with elexacaftor/tezacaftor/ivacaftor

BACKGROUND

There is a well described sex-disparity in outcomes of individuals with cystic fibrosis (CF), with females faring worse than males. Given the dramatic improvement in overall health of people with CF using CF transmembrane conductance regulator (CFTR) modulator therapy, elexacaftor/tezacaftor/ivacaftor (ETI), the sex-disparity in CF warrants re-examination.

METHODS

We evaluated the effects of ETI use by sex prior to versus after initiation of ETI by pulmonary exacerbations (PEx), percent predicted forced expiratory volume in one second (ppFEV1), presence of Pseudomonas aeruginosa in sputum cultures, and body mass index (BMI). We used univariate and multivariable longitudinal regression adjusting for key confounders, such as age, race, CFTR modulator taken prior to ETI and baseline ppFEV1.

RESULTS

We included 251 individuals started on ETI between January 2014 to September 2022. We collected data for a mean of 5.45 years pre-ETI and 2.38 years post-ETI. We found the adjusted presence of PEx decreased more in males than females pre- to post-ETI with the odds of having a PEx in males being 0.57 (43% reduction) versus females 0.75 (25% reduction) (p = 0.049). We found no statistical difference by sex for ppFEV1, presence of Pseudomonas aeruginosa or BMI pre- to post-ETI by sex.

CONCLUSION

After treatment with ETI, there was a greater decline in PEx in males versus females. Long-term impact of ETI by sex is still unknown, but we will need to seek ways to effectively tailor care for individuals with CF and consider pharmacokinetic studies of ETI comparing males to females.

Changes of androgen and corticosterone metabolites excretion and conversion in cystic fibrosis

Cystic fibrosis (CF) is a life-threatening inherited disease related to a mutation in the CFTR gene, that leads to serious health complications such as chronic pulmonary infections, pancreatic insufficiency, dysfunction of the sweat glands and reproductive system. For the first time, we have described the profile of corticosterone and androgen metabolites in urine, as well as the activity of enzymes involved in steroid genesis and metabolism in people with CF, using gas chromatography/mass spectrometry. A significant reduction in the excretion of most of the measured metabolites in CF was found. These differences were observed in the group of progestagen metabolites, as well as among metabolites of corticosterone and androgens. We revealed higher activities of 17β-hydroxysteroid dehydrogenase and 17,20-lyase in the Δ4 pathway compared with controls, what can promote the androgen synthesis through the backdoor androgen pathway. We have also found the increased conversion activity of 11-oxyganated steroids by 5a-reductase in backdoor pathway. Levels of the most potent and vital androgens (testosterone and dihydrotestosterone) are comparable in both groups. However, the excretion of dehydroepiandrosterone was lower in CF. Decreased cholesterol lipoprotein levels may contribute to limited intracellular cholesterol supply and reduced adrenal steroidogenesis in CF individuals. Changes in the activity of some steroidogenesis enzymes may suggest the presence of some peripheral adaptive mechanisms in CF to maintain androgen balance in the body despite the limited sufficiency of secretion by the adrenal cortex.

Emerging Approaches to Monitor and Modify Care in the Era of Cystic Fibrosis Transmembrane Conductance Regulators

As we characterize the clinical benefits of highly effective modulator therapy (HEMT) in the cystic fibrosis (CF) population, our paradigm for treating and monitoring disease continues to evolve. More sensitive approaches are necessary to detect early disease and clinical progression. This article reviews evolving strategies to assess disease control and progression in the HEMT era. This article also explores developments in pulmonary function monitoring, advanced respiratory imaging, tools for the collection of patient-reported outcomes, and their application to profile individual responses, guide therapeutic decisions, and improve the quality of life of people with CF.

Essential Fatty Acid Deficiency in Cystic Fibrosis Disease Progression: Role of Genotype and Sex

Adequate intake of nutrients such as essential fatty acids (EFA) are critical in cystic fibrosis (CF). The clinical course of deterioration of lung function in people with CF has been shown to relate to nutrition. Independent of the higher energy consumption and malabsorption due to pancreatic insufficiency, EFA deficiency is closely associated with the risk of pulmonary infection, the most significant pathology in CF. This review will focus on the EFA deficiency identified in people with CF, as well as the limited progress made in deciphering the exact metabolic pathways that are dysfunctional in CF. Specifically, people with CF are deficient in linoleic acid, an omega 6 fatty acid, and the ratio of arachidonic acid (omega 6 metabolite) and docosahexaenoic acid (omega 3 metabolite) is increased. Analysis of the molecular pathways in bronchial cells has identified changes in the enzymes that metabolise EFA. However, fatty acid metabolism primarily occurs in the liver, with EFA metabolism in CF liver not yet investigated, indicating that further research is required. Despite limited understanding in this area, it is well known that adequate EFA concentrations are critical to normal membrane structure and function, and thus are important to consider in disease processes. Novel insights into the relationship between CF genotype and EFA phenotype will be discussed, in addition to sex differences in EFA concentrations in people with CF. Collectively, investigating the specific effects of genotype and sex on fatty acid metabolism may provide support for the management of people with CF via personalised genotype- and sex-specific nutritional therapies.

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

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

Impact of Socioeconomic Position on Access to the U.S. Lung Transplant Waiting List in a Matched Cystic Fibrosis Cohort

Rationale: Referrals for lung transplant and transplant rates in the United States are lower than in Canada for patients with advanced cystic fibrosis (CF) lung disease. Further study of factors limiting access are needed to optimize referral and transplant for this population.Objectives: To determine the effect of socioeconomic position, while accounting for disease severity, on the likelihood of wait-listing for lung transplant in the United States.Methods: A case-control study of 3,110 patients (1,555 wait-listed, 1,555 never wait-listed) in the linked CF Foundation Patient Registry/Scientific Registry of Transplant Recipients was performed with 1:1 matching for age, forced expiratory volume in 1 second, and year. Logistic regression was performed with univariate and multivariate analyses accounting for eight clinical factors (sex, oxygen use, body mass index, hemoptysis, forced vital capacity, methicillin-resistant Staphylococcus aureus, multidrug-resistant Pseudomonas aeruginosa, and i.v. antibiotic days) and six socioeconomic factors (race, marital status, education, health insurance, median zip code income, and distance to transplant program). The CF Health Score and Socioeconomic Barrier Score were created based on summation of variables. Interactions between scores were calculated.Results: We found an inverse relationship between the probability of wait-listing and CF Health Score and Socioeconomic Barrier Score. As the CF Health Score decreased (less healthy), the probability of wait-listing increased by 69.3% from a score of 7 to 2. As the Socioeconomic Barrier Score decreased (fewer barriers), the probability of wait-listing increased by 31.7% from a score of ≥5 to 1). Regardless of illness severity, socioeconomic barriers presented an impediment to wait-listing. Individuals with higher Socioeconomic Barrier Scores accessed transplant about half as often as those with lower scores at the same level of medical severity. Analysis of interactions demonstrated a higher probability of wait-listing for individuals with moderate health severity and fewer social barriers compared with sicker individuals with more socioeconomic barriers.Conclusions: Accrual of socioeconomic barriers limits access to lung transplant irrespective of disease severity, a finding of substantial concern for patients with CF and for transplant providers. Future interventions can focus on this at-risk population early in the disease course.

A Prospective Study of the Effects of Sex Hormones on Lung Function and Inflammation in Women with Cystic Fibrosis

Rationale: Epidemiologic studies demonstrate worse outcomes in women with cystic fibrosis (CF) than men. Women are colonized earlier with respiratory pathogens and have increased rates of pulmonary exacerbations after puberty and near ovulation. The etiology of this disparity is unclear, but sex hormones may contribute to these differences.Objectives: We sought to explore whether natural hormonal fluctuations and hormonal contraception associate with changes in lung function, respiratory symptoms, or inflammatory markers.Methods: We prospectively followed women with CF who were not on hormonal contraceptives and reported regular menstrual cycles. We captured study visits at points that corresponded with menses, ovulation, and the luteal phase. A subset of subjects were subsequently placed on a standard oral estrogen/progesterone combination contraceptive pill, ethinyl estradiol/norethindrone (loestrin), and reevaluated. Measurements included lung function, symptom questionnaires, sweat tests, blood for hormone concentrations, and sputum for inflammatory markers, bacterial density, and cytology.Results: Twenty-three women participated in this study. Hormone concentrations were as expected on and off hormonal contraception. At times of peak estrogen (ovulation), there was a significant increase in sputum proinflammatory cytokines (neutrophil-free elastase) and a corresponding pattern of decrease in lung function. Proinflammatory cytokines (IL-8, TNF-α, and neutrophil-free elastase) improved when placed on hormone contraception.Conclusions: Our results show that there are potentially important fluctuations in inflammatory biomarkers in the lungs that correlate with changes in lung function in women with CF. Larger studies evaluating the impact of sex hormones on airway inflammation and immune response are necessary to better understand the clinical impact of these responses.

Sex and Gender Differences in Lung Disease

Sex differences in the anatomy and physiology of the respiratory system have been widely reported. These intrinsic sex differences have also been shown to modulate the pathophysiology, incidence, morbidity, and mortality of several lung diseases across the life span. In this chapter, we describe the epidemiology of sex differences in respiratory diseases including neonatal lung disease (respiratory distress syndrome, bronchopulmonary dysplasia) and pediatric and adult disease (including asthma, cystic fibrosis, idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease, lung cancer, lymphangioleiomyomatosis, obstructive sleep apnea, pulmonary arterial hypertension, and respiratory viral infections such as respiratory syncytial virus, influenza, and SARS-CoV-2). We also discuss the current state of research on the mechanisms underlying the observed sex differences in lung disease susceptibility and severity and the importance of considering both sex and gender variables in research studies' design and analysis.

Gender differences in bronchiectasis: a real issue?

Gender differences in chronic respiratory disease, including cystic fibrosis and non-cystic fibrosis bronchiectasis are clinically apparent and of increasing importance. Differences in disease prevalence, severity and outcome are all described, however, the precise cause of the gender dichotomy and their associated underlying mechanisms have been poorly characterised. A lack of dedicated clinical and epidemiological research focused in this area has led to a paucity of data and therefore a lack of understanding of its key drivers. Diagnosis, disease pathogenesis and treatment response are all complex but important aspects of bronchiectasis with an evident gender bias. Broadening our understanding of the interplay between microbiology, host physiology and the environment in the context of chronic lung diseases, such as bronchiectasis, is critical to unravelling mechanisms driving the observed gender differences. In this review, epidemiological, biological and environmental evidence related to gender in bronchiectasis is summarised. This illustrates gender differences as a “real issue” with the objective of mapping out a future framework upon which a gender-tailored medical approach may be incorporated into the diagnosis, monitoring and treatment of bronchiectasis.

CF and non-CF bronchiectasis are complex multifactorial chronic pulmonary diseases demonstrating gender differences in their prevalence, severity and infections, some of which are attributable to sex hormoneshttp://ow.ly/beDf30jseK4

Gender differences in outcomes of patients with cystic fibrosis

BACKGROUND

Cystic fibrosis (CF) is a common life-shortening genetic disease in which women have been described to have worse outcomes than males, particularly in response to respiratory infections with Pseudomonas aeruginosa. However, as advancements in therapies have improved life expectancy, this gender disparity has been challenged. The objective of this study is to examine whether a gender-based survival difference still exists in this population and determine the impact of common CF respiratory infections on outcomes in males versus females with CF.

METHODS

We conducted a retrospective cohort analysis of 32,766 patients from the United States Cystic Fibrosis Foundation Patient Registry over a 13-year period. Kaplan-Meier and Cox proportional hazards models were used to compare overall mortality and pathogen based survival rates in males and females.

RESULTS

Females demonstrated a decreased median life expectancy (36.0 years; 95% confidence interval [CI] 35.0-37.3) compared with men (38.7 years; 95% CI 37.8-39.6; p<0.001). Female gender proved to be a significant risk factor for death (hazard ratio 2.22, 95% CI 1.79-2.77), despite accounting for variables known to influence CF mortality. Women were also found to become colonized earlier with several bacteria and to have worse outcomes with common CF pathogens.

CONCLUSIONS

CF women continue to have a shortened life expectancy relative to men despite accounting for key CF-related comorbidities. Women also become colonized with certain common CF pathogens earlier than men and show a decreased life expectancy in the setting of respiratory infections. Explanations for this gender disparity are only beginning to be unraveled and further investigation into mechanisms is needed to help develop therapies that may narrow this gender gap.

Subcutaneous implant with etonogestrel (Implanon®) for catamenial exacerbations in a patient with cystic fibrosis: a case report

Background

Cystic Fibrosis (CF) is a genetic disease with equal prevalence across sexes. However, women present worse lung function with faster function decline, earlier onset of bacterial colonization, more frequent pulmonary exacerbations (PE), greater bronchial hyper-responsiveness, and higher mortality rates after puberty than men. The etiology of this gender disparity remains elusive but female hormones have been implicated in several studies.

Case presentation

A 20-year-old female with CF with severe recurrent PE, always related to the menstrual cycle since menarche, combined with lung function decline requiring multiple courses of intravenous antibiotics. We report the cessation of PE and recovery of pulmonary function following the insertion of a subcutaneous implant with 68 mg of etonogestrel (Implanon®, Organon Española S.A. Laboratories, Madrid, Spain).

Conclusion

Our case report supports the key role of female hormones in the development of PE and in the decline of lung function in a woman with CF. When appropriate, hormonal manipulation through contraceptive methods should be considered as potential treatment.

Long noncoding RNA are aberrantly expressed in vivo in the cystic fibrosis bronchial epithelium

Long non-coding RNAs (lncRNAs) have emerged recently as key regulatory molecules with diverse roles at almost every level of the regulation of gene expression. The roles of these RNAs in the pathogenesis of cystic fibrosis (CF); a lethal multisystem, autosomal recessive disorder have yet to be explored. Our aim was to examine the expression profile of lncRNA, in the airway epithelium of people with CF. We examined the expression of 30,586 lncRNAs by microarray (Human LncRNA Array v3.0, Arraystar, Inc.), in vivo in bronchial cells isolated from endobronchial brushings obtained from CF and non-CF individuals. In total, we identified 1,063 lncRNAs with differential expression between CF and non-CF individuals (fold change ≥3, p≤0.001). The microarray also contained probes for ∼26,109 protein coding transcripts, of which 720 were differentially expressed between CF and non-CF brush samples (fold change ≥3, p≤0.001). Confirmation of a selection of differentially expressed coding mRNA and lncRNA transcripts such as XIST and TLR8 was achieved using qRT-PCR. Gene ontology bioinformatics analysis highlighted that many processes over-represented in the CF bronchial epithelium are related to inflammation. These data show a significantly altered lncRNA and mRNA expression profile in CF bronchial cells in vivo. Dysregulation of some of these lncRNAs may play important roles in the chronic infection and inflammation that exists in the lungs of people with CF.