Cystic fibrosis: what to expect now in the early adult years

Routine spirometry in cystic fibrosis patients: impact on pulmonary exacerbation diagnosis and FEV1 decline

OBJECTIVE

Pulmonary disease in cystic fibrosis (CF) is characterised by recurrent episodes of pulmonary exacerbations (PExs), with acute and long-term declines in lung function (FEV1). The study sought to determine whether routine spirometry increases the frequency of PEx diagnosis, resulting in benefits to long-term pulmonary function.

METHODS

CF patients in the 5- to 18-year age bracket were followed for 1 year, during which they underwent spirometry before every medical visit. The main variables were the frequency of PEx diagnosis and use of antibiotics; the use of spirometry as a criterion for PEx diagnosis (a decline ≥ 10% in baseline FEV1); and median percent predicted FEV1 over time. The data were compared with those for the previous 24-month period, when spirometry was performed electively every 6 months.

RESULTS

The study included 80 CF patients. PExs were diagnosed in 27.5% of the visits, with a mean frequency of 1.44 PExs per patient/year in 2014 vs. 0.88 PExs per patient/year in 2012 (p = 0.0001) and 1.15 PExs per patient/year in 2013 (p = 0.05). FEV1 was used as a diagnostic feature in 83.5% of PExs. In 21.9% of PExs, the decision to initiate antibiotics was solely based on an acute decline in FEV1. The median percent predicted FEV1 during the follow-up year was 85.7%, being 78.5% in 2013 and 76.8% in 2012 (p > 0.05). The median percent predicted FEV1 remained above 80% during the two years after the study.

CONCLUSIONS

Routine spirometry is associated with higher rates of diagnosis and treatment of PExs, possibly impacting long-term pulmonary function.

The negative impact of chronic rhinosinusitis on the health-related quality of life among adult patients with cystic fibrosis

BACKGROUND

With improved survival in cystic fibrosis (CF) patients, it is crucial to evaluate the impact of chronic co-morbidities such as chronic rhinosinusitis (CRS). The objectives were 1) To determine the prevalence of CRS with a large series of CF patients 2) To evaluate the impact of CRS on the Health-Related Quality of Life (HRQoL) of CF patients and 3) To compare CRS-specific, CF-specific and general HRQoL instruments.

METHODS

Consecutive CF patients from the Toronto Adult Cystic Fibrosis Centre were recruited between March 2018 and January 2020. Participants completed the 22-Item Nasal Outcome Test (SNOT-22), Cystic Fibrosis Questionnaire-Revised for adolescents and adults over 14 years of age (CFQ-R), Cystic Fibrosis Quality of Life Evaluative Self-administered Test (CF-QUEST) and the 36-Item Short Form Survey (SF-36). HRQoL scores were correlated using Spearman's correlation coefficients.

RESULTS

Out of 195 patients eligible for analysis, the prevalence of CRS with positive endoscopic findings was 42.6% (95% confidence interval: 35.5-49.8%). CRS patients reported significantly lower HRQoL with higher SNOT-22 scores and lower scores in the respiratory domain of CFQ-R and physical health domains of CF-QUEST and SF-36. The physical (ρ= -0.63) and mental (ρ= -0.66) domains of SF-36 and CF-QUEST (ρ= -0.76) had a strong correlation with SNOT-22. Higher scores of SNOT-22 nasal subdomains correlated with lower scores of SF-36, CFQ-R and CF-QUEST.

CONCLUSION

CRS is a prevalent co-morbidity of CF patients, which significantly reduces HRQoL. SNOT-22, CFQ-R, CF-QUEST and SF-36 were strongly correlated. Severity of sinonasal symptoms have a strong correlation with HRQoL in CF patients.

Accuracy of the ActivPAL and Fitbit Charge 2 in measuring step count in Cystic Fibrosis

BACKGROUND

Physical activity (PA) is important in Cystic Fibrosis (CF) management. Fitness wearables are becoming increasingly popular as measurement tools of PA; however, the accuracy of these devices should first be evaluated.

OBJECTIVE

The purpose of this study was to assess the accuracy of the ActivPAL and Fitbit Charge 2 as a measure of step count in Cystic Fibrosis.

METHODS

Twenty-one participants were recruited from an adult CF Center in Ireland for a single session of testing. Participants walked for 5 min at five pre-determined speeds in a controlled testing environment (2, 2.5, 3, 3.5 and 4 miles per hour on a treadmill) and at three self-selected speeds in a corridor (slow, medium, and fast). They concurrently wore an accelerometer (ActivPAL) and fitness wearable (Fitbit Charge 2), and both were compared to visual observations. Step count is the outcome being assessed.

RESULTS

The ActivPAL under-estimated step count by 0.63% across treadmill speeds and 1.1% across self-selected walking speeds. The Fitbit Charge 2 underestimated the step count by 2.97% across treadmill speeds and by 6.3% across self-selected walking speeds. Very strong correlations were found between the ActivPAL and visual observations (r: 0.93 to 0.99), while the Fitbit Charge 2 ranged from weak to very strong correlations when compared to visual observations (r: 0.34 to 0.84).

CONCLUSION

The ActivPAL and Fitbit Charge 2 demonstrated acceptable validity for step count measurement in CF. These devices can be used for tracking PA during interventions in people with CF.

A longitudinal assessment of non-invasive biomarkers to diagnose and predict cystic fibrosis-associated liver disease

BACKGROUND & AIMS

A practical, inexpensive, and non-invasive biomarker of liver fibrosis is needed as a reliable screening test for cystic fibrosis-associated liver disease (CFLD). Studies have shown the utility of AST to Platelet Ratio Index (APRI), fibrosis index based on 4 factors (FIB-4), and gamma-glutamyl transferase (GGT) as good biomarkers for identifying CFLD. The goal of the study was to evaluate the effectiveness of APRI, FIB-4, AST/ALT ratio, platelet count, GGT, and GGT platelet ratio (GPR) in predicting CFLD development.

METHODS

Data was collected from CF Foundation Patient Registry for patients aged 3-21 years at Johns Hopkins from January 1, 2002 to December 31, 2014. Collected data included demographic characteristics, presence of splenomegaly, hepatomegaly, ascites, and variceal bleeding, AST, ALT, GGT, platelet count, and FEV₁. The sensitivity and specificity of each biomarker were analyzed and reported by the area under receiver operating characteristic (AUROC) curve.

RESULTS

By the end of the study, 144 "healthy" CF, 12 CFLD, 19 CF-associated pulmonary disease (CFPD), and 4 CFLD with CFPD cases were identified. APRI scores were higher in CFLD, 0.85 versus 0.28 in "healthy" CF and 0.23 in CFPD groups (p<0.001). GPR had the highest AUROC curve at 0.91.

CONCLUSIONS

GPR, GGT, APRI score, and platelet count were potentially useful biomarkers while FIB-4 did not predict CFLD development. Cost-effectiveness studies are needed to analyze the utility of these biomarkers in clinical practice.

Cystic fibrosis-associated liver disease in children

As improvements in nutritional and pulmonary care increase the life expectancy of cystic fibrosis (CF) patients, CF-associated liver disease (CFLD) is emerging as a cause of mortality. CFLD is the third leading cause of death in CF patients. We performed a search on PubMed and Google Scholar for published articles on CFLD. We reviewed the articles found in the literature search and gave priority to recent publications and studies with larger sample sizes. The prevalence of CFLD in the CF population is around 23% with a range of 2-62% and that prevalence increases linearly with age from 3.7% at age 5 to 32.2% at age 30. CFLD can present clinically in various ways such as hepatomegaly, variceal hemorrhage, persistent elevation of liver enzymes, and micro-gallbladder. Due to the focal nature of fibrosis in majority cases of CFLD, liver biopsies are sparsely performed for diagnosis or the marker of liver fibrosis. Although the mechanism of CFLD development is still unknown, many potential factors are reported. Some mutations of CFTR such as having a homozygous F508del mutation has been reported to increase the risk of developing CFLD and its severity. Having the SERPINA1 Z allele, a history of pancreatic insufficiency, a history meconium ileus, CF-related diabetes, or being male increases the risk of developing CFLD. Environmental factors do not appear to have significant effect on modulating CFLD development. Ursodeoxycholic acid is commonly used to treat or prevent CFLD, but the efficacy of this treatment is questionable.

Pulmonary function patterns and their association with genotype and phenotype in adult cystic fibrosis patients

Background: While cystic fibrosis (CF) lung disease is generally considered to be an obstructive disorder, other pulmonary function patterns (PFP) may occur. Furthermore, little is known about possible associations between PFP and genotype or phenotypical characteristics. Methods: Cross-sectional study including CF patients aged 16 years or more, identifying different PFP and exploring associations between PFP and genotype or phenotypical characteristics. Results: Obstructive PFP was most prevalent in our population (n = 80), comprising obstructive lung disease (62.5%), small airway (obstructive) disease (11.2%), and mixed obstructive-restrictive disorder (1.3%). However, one in four adult CF patients did not show any obstruction at all: normal (13.7%) or restrictive (8.8%) lung disease and isolated diffusion disorder (2.5%). Obstructive PFP was associated with a greater proportion of CF-related diabetes mellitus (CFRD) (P = 0.04), Pseudomonas aeruginosa colonization (P = 0.02) and frequent exacerbators (P = 0.04). We observed no association between PFP and genotype. Conclusions: Obstructive PFP remains the most common pulmonary function pattern in adult CF and is associated with CFRD, Pseudomonas aeruginosa colonization and frequent exacerbators.

Controlled evaluation of a transition clinic for Dutch young people with cystic fibrosis

BACKGROUND

Transition clinics (TCs) are advocated as best practice to support young people with cystic fibrosis (CF) during transition to adulthood and adult care. We aimed to research the functioning of a TC for young people with CF compared with direct hand-over care and to evaluate whether those treated at the TC have better transfer experiences and outcomes compared with the control group.

METHODS

Mixed-methods retrospective controlled design, including interviews with professionals, observations of clinics, chart reviews (at four measurement moments), and patient surveys. Qualitative data analysis focused on organization and daily routines, and barriers and facilitators experienced. Young people's transfer experiences, self-management, health care use, and clinical outcomes were assessed quantitatively.

RESULTS

The most notable feature distinguishing the TC and direct hand-over care comprised joint consultations between pediatric and adult care professionals in the former. A transition coordinator was considered essential for the success of the TC. The main barriers were lack of time, planning, and reimbursement issues. Young people treated at the TC tended to have better transfer experiences and were more satisfied. They reported significantly more trust in their adult care professionals. Their self-management-related outcomes were less favorable.

CONCLUSIONS

The TC had several perceived benefits and showed positive trends in transfer experiences and satisfaction, but no differences in health-related outcomes. Structured preparation of young people, joint consultations with pediatric and adult care professionals, and better coordination were perceived as facilitating elements. Further improvement demands solutions for organizational and financial barriers, and better embedding of self-management interventions in CF care.

Interventions for promoting participation in shared decision-making for children and adolescents with cystic fibrosis

BACKGROUND

Shared decision-making is important in child and adolescent healthcare because there is growing international recognition of children and young people's rights to be included in decisions that affect them. In order for young people to participate effectively in shared decision-making they need to develop the skills of engagement with healthcare professionals and confidence in interacting with them. They also need to learn how to manage their condition and treatments on their own when they move into adulthood. Children and young people who participate in shared decision-making in healthcare are likely to be more informed, feel more prepared, and experience less anxiety about the unknown. Significant improvements in cystic fibrosis (CF) survival over recent decades, due to improved therapies and better management of care, means that young people with CF are routinely transitioning to adult healthcare where increasing emphasis on self-management brings greater complexity in decision-making. We need to know what interventions are effective in promoting shared decision-making for young people with CF.

OBJECTIVES

To assess the effectiveness of interventions that promote participation in shared decision-making for children and adolescents (aged between four and 18 years) with CF.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearches of journals and conference abstract books. We also searched the reference lists of articles and reviews addressing shared decision-making.Date of most recent search: 12 March 2019.We searched PubMed, CINAHL (EBSCO), Embase (Elsevier), PsycINFO (EBSCO), WHO ICTRP, ASSIA (ProQuest), ERIC (ProQuest), ProQuest Dissertations and Theses, and ClinicalTrials.gov. We contacted study authors with published relevant research in shared decision-making for adults to ask if they were aware of any published or ongoing studies on the promotion of the intervention for children or adolescents (or both) with CF.Date of most recent search: 19 March 2019.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) (but not cross-over RCTs) of interventions promoting shared decision-making for children and adolescents with CF aged between four and 18 years, such as information provision, booklets, two-way interaction, checking understanding (by the participant), preparation to participate in a healthcare decision, decision-aids, and training interventions or educational programs. We planned to include interventions aimed at children or adolescents (or both), parents or healthcare professionals or any combination of these groups provided that the focus was aimed at promoting shared decision-making for children and adolescents with CF.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed papers identified in the searches.

MAIN RESULTS

No eligible RCTs were identified for inclusion in this systematic review.

AUTHORS' CONCLUSIONS

We were unable to identify RCTs with evidence which would support healthcare policy-making and practice related to implementation of shared decision-making for children and adolescents (aged between four and 18 years) with CF). We hope that having identified this gap in research, awareness will increase amongst researchers of the need to design high-quality shared decision-making interventions for young people with CF, perhaps adapted from existing models for adults, and to test these interventions and children's preferences in RCTs. It is also important to target health professionals with evidence-based education programmes on shared decision-making and a need for international consensus on addressing the variability in education programmes.

The emerging burden of liver disease in cystic fibrosis patients: A UK nationwide study

Objective

Cystic fibrosis associated liver disease (CFLD) is the third largest cause of mortality in CF. Our aim was to define the burden of CFLD in the UK using national registry data and identify risk factors for progressive disease.

Methods

A longitudinal population-based cohort study was conducted. Cases were defined as all patients with CFLD identified from the UK CF Registry, 2008–2013 (n = 3417). Denominator data were derived from the entire UK CF Registry. The burden of CFLD was characterised. Regression analysis was undertaken to identify risk factors for cirrhosis and progression.

Results

Prevalence of CFLD increased from 203.4 to 228.3 per 1000 patients during 2008–2013. Mortality in CF patients with CFLD was more than double those without; cirrhotic patients had higher all-cause mortality (HR 1.54, 95% CI 1.09 to 2.18, p = 0.015). Median recorded age of cirrhosis diagnosis was 19 (range 5–53) years. Male sex, Pseudomonas airway infection and CF related diabetes were independent risk factors for cirrhosis. Ursodeoxycholic acid use was associated with prolonged survival in patients without cirrhosis.

Conclusions

This study highlights an important changing disease burden of CFLD. The prevalence is slowly increasing and, importantly, the disease is not just being diagnosed in childhood. Although the role of ursodeoxycholic acid remains controversial, this study identified a positive association with survival.

Novel Guanidine Compound against Multidrug-Resistant Cystic Fibrosis-Associated Bacterial Species

Chronic pulmonary infection is a hallmark of lung disease in cystic fibrosis (CF). Infections dominated by non-fermentative Gram-negative bacilli are particularly difficult to treat and highlight an urgent need for the development of new class of agents to combat these infections. In this work, a small library comprising thiourea and guanidine derivatives with low molecular weight was designed; these derivatives were studied as antimicrobial agents against Gram-positive, Gram-negative, and a panel of drug-resistant clinical isolates recovered from patients with CF. One novel compound, a guanidine derivative bearing adamantane-1-carbonyl and 2-bromo-4,6-difluouro-phenyl substituents (H-BDF), showed potent bactericidal activity against the strains tested, at levels generally higher than those exhibited by tobramycin, ceftazimide and meropenem. The role that different substituents exert in the antimicrobial activity has been determined, highlighting the importance of the halo-phenyl group in the guanidine moiety. The new compound displays low levels of cytotoxicity against THP-1 and A549 cells with a selective index (SI) > 8 (patent application PCT/IB2017/054870, August 2017). Taken together, our results indicate that H-BDF can be considered as a promising antimicrobial agent.

The experience of men and women with cystic fibrosis who have become a parent: A qualitative study

AIMS AND OBJECTIVES

To explore the experiences of men and women with cystic fibrosis in becoming parents.

BACKGROUND

As lifespan for people with cystic fibrosis increases, and reproductive technology advances, having a child of their own becomes a possibility.

DESIGN

This study used a phenomenological framework.

METHODS

Seven Australian adults with cystic fibrosis were invited to describe their experiences of becoming parents in the context of a semi-structured interview. Analysis of the data involved highlighting recurrent phrases and isolating emergent themes.

RESULTS

Two overarching themes characterised the participants' experience: Counting the cost, as they recalled Concentric communication and Pathways to pregnancy; and Living the dream, as they cast a retrospective view over this, their major achievement, in the light of their Reaction: a dream comes true, Coping: a question of balance, Conjecture: the future redefined and Confidence: recalibrating.

CONCLUSIONS

While advances in cystic fibrosis care and reproductive technology have increased the possibility of individuals with cystic fibrosis becoming parents, the passage to becoming a parent is a complex process.

RELEVANCE TO CLINICAL PRACTICE

These findings can inform health professionals to support the adaptive work necessary for families that include members with cystic fibrosis. A contemporary understanding of this phenomenon is necessary for facilitating clinically relevant communication.

Burkholderia cepacia complex and limited cutaneous vasculitis in patients with cystic fibrosis: a case series

There is a high association of reactive skin presentations, mainly limited cutaneous vasculitis in patients with cystic fibrosis and Burkholderia cepcia complex chronic infection. This may be due to raised levels of circulating inflammatory mediators.

Factors associated with changes in health-related quality of life in children with cystic fibrosis during 1-year follow-up

There are limited data on health-related quality of life (HRQoL) changes over time in children with cystic fibrosis (CF). We investigated associations between clinical and treatment variables with changes in HRQoL during 1 year. Forty-nine children with CF aged 6-18 years were followed in this multicentre, observational cohort study during 1 year. HRQoL was measured by the validated disease specific cystic fibrosis questionnaire-revised (CFQ-R). The CFQ-R total score as well as most domain scores improved significantly (8.0 points and [3.3-31.7] points respectively) during the one-year follow-up. Age at baseline demonstrated a strong longitudinal association with the change of CFQ-R total score (2.853 points decrease of CFQ-R total score per year increase in age) and several domain scores. Below 12 years of age, CFQ-R total score improved in most children, whereas a deterioration was observed in most children above 12 years. The number of PEx was associated with an increase of treatment burden score (4.466 points decrease per extra PEx).

CONCLUSION

In the group as a whole, HRQoL improved significantly over time. However, changes over time were significantly influenced by age: below 12 years of age, HRQoL improved in most patients whereas a deterioration was observed in most children >12 years. Strategies how to preserve or ideally to improve HRQoL in adolescence should be developed. What is known: • Quality of life in patient with CF is diminished • Although CF is a chronic disease, longitudinal data on QoL in children with CF are scarce. What is new: • Below 12 years of age, quality of life improved in most children during the 1-year follow-up whereas a deterioration in quality of life was observed in most children above 12 years. • the treatment burden score of QoL correlated with the exacerbation rate.

Microbiome in the pathogenesis of cystic fibrosis and lung transplant-related disease

Significant advances in culture-independent methods have expanded our knowledge about the diversity of the lung microbial environment. Complex microorganisms and microbial communities can now be identified in the distal airways in a variety of respiratory diseases, including cystic fibrosis (CF) and the posttransplantation lung. Although there are significant methodologic concerns about sampling the lung microbiome, several studies have now shown that the microbiome of the lower respiratory tract is distinct from the upper airway. CF is a disease characterized by chronic airway infections that lead to significant morbidity and mortality. Traditional culture-dependent methods have identified a select group of pathogens that cause exacerbations in CF, but studies using bacterial 16S rRNA gene-based microarrays have shown that the CF microbiome is an intricate and dynamic bacterial ecosystem, which influences both host immune health and disease pathogenesis. These microbial communities can shift with external influences, including antibiotic exposure. In addition, there have been a number of studies suggesting a link between the gut microbiome and respiratory health in CF. Compared with CF, there is significantly less knowledge about the microbiome of the transplanted lung. Risk factors for bronchiolitis obliterans syndrome, one of the leading causes of death, include microbial infections. Lung transplant patients have a unique lung microbiome that is different than the pretransplanted microbiome and changes with time. Understanding the host-pathogen interactions in these diseases may suggest targeted therapies and improve long-term survival in these patients.

Contraceptive safety among women with cystic fibrosis: a systematic review

BACKGROUND

With dramatic improvements in life expectancy for cystic fibrosis (CF) patients, contraception for women with CF has become an important issue. There are theoretical concerns that hormonal contraceptive use among women with CF may impact disease severity or risk for other adverse health outcomes, including thrombosis and poor bone health, as well as concerns that malabsorption or altered drug metabolism might impact contraceptive effectiveness.

OBJECTIVE

To evaluate evidence on the safety and effectiveness of contraceptive methods among women with CF.

SEARCH STRATEGY

We searched the PubMed database for all articles published from database inception through October 2015.

SELECTION CRITERIA

We included studies that examined measures of disease severity, other health outcomes or indicators of contraceptive effectiveness among women with CF initiating or continuing a contraceptive method.

RESULTS

Seven studies met our inclusion criteria. Three observational studies of fair to poor quality suggest that use of oral contraceptives (OCs) does not negatively impact CF disease severity, defined as changes in pulmonary function, number of exacerbations or need for intravenous antibiotics. Three small studies of poor quality reported on contraceptive failure among women with CF using combined hormonal contraceptives (combined OCs, patch or ring). One pregnancy was reported in a patch user out of 43 hormonal contraceptive users across all studies. One pharmacokinetic study reported that women with CF achieve steroid hormone plasma concentrations similar to healthy women after ingestion of combined OCs.

CONCLUSIONS

Limited evidence suggests that hormonal contraceptive use does not negatively impact disease severity among women with CF and that hormonal contraceptive effectiveness is not impaired by CF. Studies were limited by small sample sizes and short duration of follow-up. No studies examined the effect of hormonal contraception on thrombosis or bone health among women with CF.

Vitamin D3 supplementation among adult patients with cystic fibrosis

BACKGROUND & AIMS

Vitamin D (Vit D) deficiency in cystic fibrosis (CF) is partially secondary to exocrine pancreatic insufficiency. Our aim was to establish a Vit D₃ supplementation protocol that will increase 25(OH)D to the recommended level (30 ng/mL).

METHODS

Retrospective study of 200 patients (≥18 years) conducted from February 2007 to June 2014 at the CF clinic of the Centre Hospitalier de l'Université de Montréal. Vit D₃ supplementation protocol was 1600 IU/day or 10,000 IU/week during the summer (May 1st to October 31st) and 3200 IU/day or 20,000 IU/week during the winter (November 1st to April 30th), in addition to the 1200 IU/day included in multivitamins.

RESULTS

Significant increase in serum 25(OH)D levels from baseline (25.9 ± 10.3 ng/mL) to follow-up (37.0 ± 11.4 ng/mL) (P ≤ 0.001). At follow-up, increased doses during the winter improved serum 25(OH)D levels to a degree comparable to the summer.

CONCLUSIONS

This supplementation protocol is efficient and needs to be tested in other CF adult cohorts and correlated to potential health benefit measurements.

Evaluating outpatient transition clinics: a mixed-methods study protocol

INTRODUCTION

To support young people in their transition to adulthood and transfer to adult care, a number of interventions have been developed. One particularly important intervention is the transition clinic (TC), where paediatric and adult providers collaborate. TCs are often advocated as best practices in transition care for young people with chronic conditions, but little is known about TC models and effects. The proposed study aims to gain insight into the added value of a TC compared with usual care (without a TC).

METHODS AND ANALYSIS

We propose a mixed-methods study with a retrospective controlled design consisting of semistructured interviews among healthcare professionals, observations of consultations with young people, chart reviews of young people transferred 2-4 years prior to data collection and questionnaires among the young people included in the chart reviews. Qualitative data will be analysed through thematic analysis and results will provide insights into structures and daily routines of TCs, and experienced barriers and facilitators in transitional care. Quantitatively, within-group differences on clinical outcomes and healthcare use will be studied over the four measurement moments. Subsequently, comparisons will be made between intervention and control groups on all outcomes at all measurement moments. Primary outcomes are 'no-show after transfer' (process outcome) and 'experiences and satisfaction with the transfer' (patient-reported outcome). Secondary outcomes consider clinical outcomes, healthcare usage, self-management outcomes and perceived quality of care.

ETHICS

The Medical Ethical Committee of the Erasmus Medical Centre approved the study protocol (MEC-2014-246).

DISSEMINATION

Study results will be disseminated through peer-reviewed journals and conferences. The study started in September 2014 and will continue until December 2016. The same study design will be used in a national study in 20 diabetes settings (2016-2018).

Comparative genomics of non-pseudomonal bacterial species colonising paediatric cystic fibrosis patients

The genetic disorder cystic fibrosis is a life-limiting condition affecting ∼70,000 people worldwide. Targeted, early, treatment of the dominant infecting species, Pseudomonas aeruginosa, has improved patient outcomes; however, there is concern that other species are now stepping in to take its place. In addition, the necessarily long-term antibiotic therapy received by these patients may be providing a suitable environment for the emergence of antibiotic resistance. To investigate these issues, we employed whole-genome sequencing of 28 non-Pseudomonas bacterial strains isolated from three paediatric patients. We did not find any trend of increasing antibiotic resistance (either by mutation or lateral gene transfer) in these isolates in comparison with other examples of the same species. In addition, each isolate contained a virulence gene repertoire that was similar to other examples of the relevant species. These results support the impaired clearance of the CF lung not demanding extensive virulence for survival in this habitat. By analysing serial isolates of the same species we uncovered several examples of strain persistence. The same strain of Staphylococcus aureus persisted for nearly a year, despite administration of antibiotics to which it was shown to be sensitive. This is consistent with previous studies showing antibiotic therapy to be inadequate in cystic fibrosis patients, which may also explain the lack of increasing antibiotic resistance over time. Serial isolates of two naturally multi-drug resistant organisms, Achromobacter xylosoxidans and Stenotrophomonas maltophilia, revealed that while all S. maltophilia strains were unique, A. xylosoxidans persisted for nearly five years, making this a species of particular concern. The data generated by this study will assist in developing an understanding of the non-Pseudomonas species associated with cystic fibrosis.

Generation of Distal Airway Epithelium from Multipotent Human Foregut Stem Cells

Collectively, lung diseases are one of the largest causes of premature death worldwide and represent a major focus in the field of regenerative medicine. Despite significant progress, only few stem cell platforms are currently available for cell-based therapy, disease modeling, and drug screening in the context of pulmonary disorders. Human foregut stem cells (hFSCs) represent an advantageous progenitor cell type that can be used to amplify large quantities of cells for regenerative medicine applications and can be derived from any human pluripotent stem cell line. Here, we further demonstrate the application of hFSCs by generating a near homogeneous population of early pulmonary endoderm cells coexpressing NKX2.1 and FOXP2. These progenitors are then able to form cells that are representative of distal airway epithelium that express NKX2.1, GATA6, and cystic fibrosis transmembrane conductance regulator (CFTR) and secrete SFTPC. This culture system can be applied to hFSCs carrying the CFTR mutation Δf508, enabling the development of an in vitro model for cystic fibrosis. This platform is compatible with drug screening and functional validations of small molecules, which can reverse the phenotype associated with CFTR mutation. This is the first demonstration that multipotent endoderm stem cells can differentiate not only into both liver and pancreatic cells but also into lung endoderm. Furthermore, our study establishes a new approach for the generation of functional lung cells that can be used for disease modeling as well as for drug screening and the study of lung development.

Lung transplantation for cystic fibrosis: results, indications, complications, and controversies

Survival in patients with cystic fibrosis (CF) has improved dramatically over the past 30 to 40 years, with mean survival now approximately 40 years. Nonetheless, progressive respiratory insufficiency remains the major cause of mortality in CF patients, and lung transplantation (LT) is eventually required. Timing of listing for LT is critical, because up to 25 to 41% of CF patients have died while awaiting LT. Globally, approximately 16.4% of lung transplants are performed in adults with CF. Survival rates for LT recipients with CF are superior to other indications, yet LT is associated with substantial morbidity and mortality (∼50% at 5-year survival rates). Myriad complications of LT include allograft failure (acute or chronic), opportunistic infections, and complications of chronic immunosuppressive medications (including malignancy). Determining which patients are candidates for LT is difficult, and survival benefit remains uncertain. In this review, we discuss when LT should be considered, criteria for identifying candidates, contraindications to LT, results post-LT, and specific complications that may be associated with LT. Infectious complications that may complicate CF (particularly Burkholderia cepacia spp., opportunistic fungi, and nontuberculous mycobacteria) are discussed.

Inflammation, oxidative stress, and cardiovascular disease risk factors in adults with cystic fibrosis

Cystic fibrosis (CF) represents one of a number of localized lung and non-lung diseases with an intense chronic inflammatory component associated with evidence of systemic oxidative stress. Many of these chronic inflammatory diseases are accompanied by an array of atherosclerotic processes and cardiovascular disease (CVD), another condition strongly related to inflammation and oxidative stress. As a consequence of a dramatic increase in long-lived patients with CF in recent decades, the specter of CVD must be considered in these patients who are now reaching middle age and beyond. Buttressed by recent data documenting that CF patients exhibit evidence of endothelial dysfunction, a recognized precursor of atherosclerosis and CVD, the spectrum of risk factors for CVD in CF is reviewed here. Epidemiological data further characterizing the presence and extent of atherogenic processes in CF patients would seem important to obtain. Such studies should further inform and offer mechanistic insights into how other chronic inflammatory diseases potentiate the processes leading to CVDs.

Medication beliefs mediate between depressive symptoms and medication adherence in cystic fibrosis

OBJECTIVE

Depression is a known barrier to regimen adherence for chronic conditions. Despite elevated depression rates and complex regimens for people with cystic fibrosis (CF), little is known about associations between depressive symptoms and CF adherence. One possibility is that depressive symptoms distort beliefs about medications, which may influence adherence.

METHOD

Adolescents and adults (N = 128; mean age = 29 ± 11 years, range = 16-63, 93% Caucasian) with CF reported on depressive symptoms and medication beliefs (self-efficacy, motivation, perceived importance, and outcome expectancies related to taking medications). Medication adherence was assessed objectively through pharmacy refill data. Cross-sectional structural equation models evaluated medication beliefs as a mediator between depressive symptoms and medication adherence.

RESULTS

Twenty-three percent of participants exceeded clinical cutoffs for depressive symptoms. Participants took less than half of prescribed pulmonary medications (mean adherence rate = 44.4 ± 26.7%). Depressive symptoms were correlated with adherence (r = -.22, p < .05), and medication beliefs (b = -0.13, 95% CI [-0.24, -0.03]) significantly mediated this relation. Higher depressive symptoms were associated with less positive medication beliefs (b = -0.27, p < .01), which were associated with lower medication adherence (b = 0.49, p < .01).

CONCLUSIONS

Depressive symptoms are related to beliefs about and adherence to CF medications. Monitoring depressive symptoms and medication beliefs in routine CF care may help identify risks for nonadherence and facilitate interventions to reduce depression, adaptive medication beliefs, and ultimately improve adherence and CF management. (PsycINFO Database Record

The clinical significance of the gut microbiota in cystic fibrosis and the potential for dietary therapies

Cystic fibrosis (CF) is characterised by many comorbidities related to aberrant mucosa and chronic inflammation in the respiratory and digestive systems. The intestinal mucosa serves as the primary interface between the gut microbiota and endocrine, neural and immune systems. There is emerging evidence that aberrant intestinal mucosa in CF may associate with an altered gut microbiota. Compared to healthy subjects, the overall bacterial abundance and species richness seems to be reduced in CF, accompanied by a trend in suppression of Firmicutes and Bacteroidetes spp. and an augmentation of potentially pathogenic species. There is also some concordance of gut and respiratory microbiotas in CF infants over time. The clinical significance of these observations awaits investigation. The gut microbiota have some potential in CF management by affecting inflammatory and immune responses, and influencing aberrant mucosa. As an important modifiable factor, diet therapies such as probiotics and prebiotics have shown initial promise in improving CF related conditions associated with chronic inflammation. More studies are needed to confirm this, as well as the efficacy of other dietary strategies such as modulating dietary fat and indigestible carbohydrate. Similarly, dietary modification of gut microbiota to optimise nutritional status in CF may be feasible, although more CF-specific studies are warranted.

Bisphosphonates for osteoporosis in people with cystic fibrosis

BACKGROUND

Osteoporosis is a bone mineralisation disorder occurring in about one third of adults with cystic fibrosis. Bisphosphonates can increase bone mineral density and decrease the risk of new fractures in post-menopausal women and people receiving long-term oral corticosteroids.

OBJECTIVES

To assess the effects of bisphosphonates on the frequency of fractures, bone mineral density, quality of life, adverse events, trial withdrawals, and survival in people with cystic fibrosis.

SEARCH METHODS

We searched the Cystic Fibrosis and Genetic Disorders Group Trials Register of references (identified from electronic database searches and handsearches of journals and abstract books) on 13 January 2014.Additional searches of PubMed were performed on 13 January 2014.

SELECTION CRITERIA

Randomised controlled trials of at least six months duration studying bisphosphonates in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials and extracted data. Trial investigators were contacted to obtain missing data.

MAIN RESULTS

Nine trials were identified and seven (with a total of 237 adult participants) were included.Data were combined (when available) from six included studies in participants without a lung transplant. Data showed that there was no significant reduction in fractures between treatment and control groups at 12 months, odds ratio 0.72 (95% confidence interval 0.13 to 3.80). No fractures were reported in studies with follow-up at 24 months. However, in patients taking bisphosphonates after six months the percentage change in bone mineral density increased at the lumbar spine, mean difference 4.61 (95% confidence interval 3.90 to 5.32) and at the hip or femur, mean difference 3.35 (95% confidence interval 1.63 to 5.07); but did not significantly change at the distal forearm, mean difference -0.49 (95% confidence interval -2.42 to 1.45). In patients taking bisphosphonates, at 12 months the percentage change in bone mineral density increased at the lumbar spine, mean difference 6.10 (95% confidence interval 5.10 to 7.10) and at the hip or femur, mean difference 4.35 (95% confidence interval 2.99 to 5.70). At 24 months, in patients treated with bisphosphonates the percentage change in bone mineral density also increased at the lumbar spine, mean difference 5.49 (95% confidence interval 4.38 to 6.60) and at the hip or femur, mean difference 6.05 (95% confidence interval 3.74 to 8.36). There was clinical heterogeneity between studies and not all studies reported all outcomes. Bone pain was the most common adverse event with intravenous agents. Flu-like symptoms were also increased in those taking bisphosphonates.In participants with a lung transplant (one study), intravenous pamidronate did not change the number of new fractures. At axial sites, bone mineral density increased with treatment compared to controls: percentage change in bone mineral density at lumbar spine, mean difference 6.20 (95% confidence interval 4.28 to 8.12); and femur mean difference 7.90 (95% confidence interval 5.78 to 10.02).

AUTHORS' CONCLUSIONS

Oral and intravenous bisphosphonates increase bone mineral density in people with cystic fibrosis. Severe bone pain and flu-like symptoms may occur with intravenous agents. Additional trials are needed to determine if bone pain is more common or severe (or both) with the more potent zoledronate and if corticosteroids ameliorate or prevent these adverse events. Additional trials are also required to further assess gastrointestinal adverse effects associated with oral bisphosphonates. Trials in larger populations are needed to determine effects on fracture rate and survival.

Quantifying insulin sensitivity and entero-insular responsiveness to hyper- and hypoglycemia in ferrets

Ferrets are an important emerging model of cystic fibrosis related diabetes. However, there is little documented experience in the use of advanced techniques to quantify aspects of diabetes pathophysiology in the ferret. Glycemic clamps are the gold standard technique to assess both insulin sensitivity and insulin secretion in humans and animal models of diabetes. We therefore sought to develop techniques for glycemic clamps in ferrets. To assess insulin sensitivity, we performed euglycemic hyperinsulinemic clamps in 5–6 week old ferrets in the anesthetized and conscious states. To assess insulin secretion, we performed hyperglycemic clamps in conscious ferrets. To evaluate responsiveness of ferret islet and entero-insular hormones to low glucose, a portion of the hyperglycemic clamps were followed by a hypoglycemic clamp. The euglycemic hyperinsulinemic clamps demonstrated insulin responsiveness in ferrets similar to that previously observed in humans and rats. The anesthetic isoflurane induced marked insulin resistance, whereas lipid emulsion induced mild insulin resistance. In conscious ferrets, glucose appearance was largely suppressed at 4 mU/kg/min insulin infusion, whereas glucose disposal was progressively increased at 4 and 20 mU/kg/min insulin. Hyperglycemic clamp induced first phase insulin secretion. Hypoglycemia induced a rapid diminishment of insulin, as well as a rise in glucagon and pancreatic polypeptide levels. The incretins GLP-1 and GIP were affected minimally by hyperglycemic and hypoglycemic clamp. These techniques will prove useful in better defining the pathophysiology in ferrets with cystic fibrosis related diabetes.