The Changing Landscape of Nutrition in Cystic Fibrosis: The Emergence of Overweight and Obesity

Sex disparities in cystic fibrosis in the era of highly effective modulator treatment

Cystic fibrosis (CF) is a genetic disorder characterized by progressive lung disease and extra-pulmonary manifestations with notable sex disparities in disease outcomes. In this review we summarize the underlying mechanisms driving this sex disparity, with a particular focus on the role of sex hormones on CF lung disease pathophysiology. We explore how the introduction of highly effective modulator therapies (HEMT) may impact sex differences in outcomes and assess whether they have the potential to close the sex gap. While treatment with HEMT has led to better outcomes in the CF population as a whole, females with CF continue to experience worse pulmonary morbidity than males. There is a need for continued research in this area, particularly into the influence and therapeutic potential of sex hormones.

The Aging Patient with Cystic Fibrosis

Cystic fibrosis (CF) is an inherited condition that leads to multiorgan dysfunction, especially in the respiratory, gastrointestinal, and reproductive tracts, with associated conditions including persistent pulmonary infection, liver disease, pancreatic insufficiency, and infertility. Historically, people with CF (pwCF) suffered a shortened lifespan due to complications of the condition, namely respiratory. The emphasis on center-based, multidisciplinary care and the widespread introduction of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy has resulted in pwCF living longer and healthier lives. Now they may encounter some of the health and social issues associated with growing older, which previously were not a typical experience for this population. In this article, we review relevant health issues for the aging CF population, including complications that arise from the condition itself, issues encountered due to treatment, and general conditions associated with aging that may manifest earlier or differently in pwCF. We discuss the recommendations for screening and treatment of relevant conditions, and considerations for the integration of healthcare professionals across disciplines into the care of this population.

A systematic review of the impact of Elexacaftor/Tezacaftor/Ivacaftor on body composition in people with cystic fibrosis

Elexacaftor/Tezacaftor/Ivacaftor (ETI) has led to improved lung function, life expectancy, and body mass index for people with Cystic Fibrosis (CF). The aim of this systematic review was to evaluate the impact that ETI has had on body composition in people with CF. A systematic review was performed using MEDLINE, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials. Quality assessment using the Joanna Briggs Institute critical appraisal tools were performed. Results were summarised narratively. Five observational cohort studies involving a total of 185 participants were reviewed. Three studies showed an increase in fat mass (7.0-8.6 kg, 13.2-14.3 kg, and 13.4-15.5 kg). Two studies reported an increase in fat-free mass (49.4-50.1 kg, 52.5-55 kg), while one reported a decrease (50.5-48.9 kg). Two studies found an increase in fat mass index (4.1-6.3 kgm/2 and 4.7-5.4 kg/m2) and fat-free mass index (17.4-17.7 kg/m2 and 18.1-18.8 kg/m2). Two studies observed an increase in percentage body fat mass (12.1-15.4% and 23.1-27.6%). Four studies were classified as low quality, while one was considered medium quality. This review suggest that commencing ETI results in changes in body composition. Firm conclusions about the type and distribution of change in body composition cannot be made due to limited studies, high heterogeneity, and methodical weaknesses. It highlights the necessity for higher quality and longer-term studies to explore the impact that ETI is having on body composition.

The overlooked factor: Sleep quality in assessing malnutrition risk and nutritional status in adolescents with cystic fibrosis

AIM

This study aimed to assess the relationship between sleep quality, malnutrition risk, and nutritional status in adolescents with cystic fibrosis(CF).

MATERIAL AND METHOD

This cross-sectional study was conducted with 55 adolescents (aged 10-18 years) diagnosed with CF. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), and malnutrition risk was evaluated based on disease-specific criteria. Nutritional status was assessed using body mass index (BMI), BMI percentiles, dietary energy intake, and food group consumption. Multiple linear regression analyses were used to determine the relationship between sleep quality, malnutrition risk, and nutritional status.

RESULTS

Among the participants, 50.9 % had poor sleep quality, and 29.1 % were classified as high-risk for malnutrition. Poor sleep quality was significantly associated with increased malnutrition risk (p < 0.05), independent of dietary energy intake and BMI percentiles. Lower BMI percentile was strongly associated with higher malnutrition risk (p < 0.001), identifying BMI as a critical predictor. Specifically, 27.3 % of participants had a BMI <10th percentile, which contributed to their classification as high-risk for malnutrition. However, dietary energy intake did not significantly predict malnutrition risk despite its relevance in dietary management.

CONCLUSION

This study emphasizes the crucial role of sleep quality in assessing malnutrition risk among adolescents with CF. Poor sleep quality was associated with higher malnutrition risk, suggesting that sleep disturbances may contribute to nutritional challenges. Sleep quality should be considered a key factor in assessing malnutrition risk among adolescents with CF and integrated into clinical practice to develop comprehensive management strategies addressing sleep disturbances and nutritional challenges, improving health outcomes.

Pilot and feasibility study of dietary composition with elexacaftor-tezacaftor-ivacaftor concentrations in people with cystic fibrosis

BACKGROUND

Nutritional support for people with cystic fibrosis (PwCF) after the implementation of novel drug therapies is shifting from managing malnutrition through a high-fat, high-calorie diet to managing emerging incidences of obesity in this population. Additionally, dietary recommendations prescribed with elexacaftor/tezacaftor/ivacaftor (ETI) recommend taking this drug with a fat-containing meal, which is variably interpreted by patients. This pilot and feasibility study was conducted to assess dietary fat intake and body composition on ETI plasma concentrations.

METHODS

Ten participants were enrolled in a 1:1 crossover design by dietary recommendations. To mimic recommendations made during routine clinical care, participants were instructed to consume either a general healthful diet (no more than 30% calories from fat) or a high-fat diet (>40% calories from fat) for a week before crossing over to the alternative diet.

RESULTS

This pilot study was acceptable to and feasible for study participants. Most participants increased fat intake calories when following a high-fat diet. Body composition measurements showed a trending correlation between lean mass and fat-free mass with ETI plasma concentrations. ETI compounds were quantified in plasma at 0 h (prior to the ETI morning dose) and 6 h after ingestion, and consuming a high-fat diet did not significantly impact ETI concentrations.

CONCLUSIONS

Consuming a higher-fat diet did not significantly impact ETI plasma concentrations, and all participants were in range for clinical effectiveness of ETI regardless of fat intake. This work provides vital pilot data to design larger studies to clarify dietary composition for optimal ETI exposure for PwCF on this therapy.

Cystic fibrosis foundation position paper: Redefining the cystic fibrosis care team

Interdisciplinary teams care for people with cystic fibrosis (pwCF) at specialized treatment centers. These teams have laid the foundation for the cystic fibrosis (CF) care model responsible for gains in health outcomes and quality of life within the CF community. However, the landscape of CF care is transforming, invigorated by new technologies, accessibility of cystic fibrosis transmembrane conductance regulator (CFTR) therapies, and increased utilization of telemedicine. In light of these advances, it is appropriate to re-evaluate the CF care team structure. This position paper offers guidance for the structure of a CF care center designed to meet the evolving needs of the CF community. Fundamental to the proposed center structure is recognition of pwCF and their families as integral members of their care teams, underpinning the necessity for shared decision making, awareness of social determinants of health, and active partnership between all healthcare professionals involved in the care of pwCF.

Heightened mitochondrial respiration in CF cells is normalised by triple CFTR modulator therapy through mechanisms involving calcium

Background

Cystic fibrosis (CF) is associated with increased resting energy expenditure. However, the introduction of elexacaftor/tezacaftor/ivacaftor (ETI) has resulted in a paradigm shift in nutritional status for many people with CF, with increase body mass index and reduction in the need for nutritional support. While these changes are likely to reflect improved clinical status and an associated downregulation of energy expenditure, they may also reflect drug-induced alterations in metabolic perturbations within CF cells. We hypothesise that some of these changes relate to normalisation of mitochondrial respiration in CF.

Methods

Using wild-type (WT) and F508del/F508del CFTR human bronchial epithelial cell lines (HBE cell lines) and baby hamster kidney (BHK) cells we examined the impact of ETI on cellular metabolism. We monitored mitochondrial respiration, using Seahorse extracellular flux assays and monitored mitochondrial reactive oxygen species (mROS) and intracellular calcium levels by flow cytometry.

Results

Increased mitochondrial respiration was found in HBE cell lines and BHK cells expressing CFTR F508del/F508del when assessing basal, maximal, spare respiratory capacities and ATP production, as well as increased mitochondrial ROS generated via forward electron transport. ETI significantly decreased basal, maximal, spare respiratory capacity and ATP production to WT levels or below. Calcium blocker, BAPTA-AM normalised mitochondrial respiration, suggesting a calcium-mediated mechanism. ETI decreased intracellular calcium levels in CF cells to the same extent as BAPTA-AM, highlighting the importance of calcium and chloride in mitochondrial respiration in CF.

Conclusions

CF cell lines exhibit increased mitochondrial respiration, which can be downregulated by ETI therapy through mechanisms involving calcium.

Is Obesity a Problem in New Cystic Fibrosis Treatments?

INTRODUCTION

Malnutrition has always been a problem in CF (cystic fibrosis) patients; however, new treatments with CFTR (cystic fibrosis transmembrane conductance regulator protein) modulators have led to weight gain, with some patients at risk of overweight and obesity.

OBJECTIVE

Our study aimed to analyze the evolution of BMI (body mass index) after one year of treatment with triple therapy and the factors associated with weight gain in CF patients undergoing treatment with triple therapy with CFTR protein modulators (ETI) (elexacaftor/tezacaftor/ivacaftor).

METHODS

We conducted a prospective, observational, longitudinal, multicenter study in patients diagnosed with cystic fibrosis, aged 18 years or older, with at least one F508del allele and who underwent ETI therapy for at least one year, from 2020 to 2023. One hundred and eight patients from two cystic fibrosis units in Spain, Princess University Hospital of Madrid (74 patients) and Central University Hospital of Asturias (HUCA) (34 patients), were included. Demographic data, anthropometric data, lung function, and exacerbations were collected, comparing the data in the previous year to the start of therapy with the results after one year of treatment. Multivariant models were developed to account for repeated weight and BMI measurements, using a mixed effects model approach and accounting for possible modifying factors Results: One hundred and eight patients were included in the study, 58 men (53.7%) and 50 women (46.3%) with a mean age of 29.5 ± 9.4 years (18-59). Patient weight and BMI were recorded at baseline and at 3-month intervals during the study period. The weight increased from 59.6 kg to 62.6 kg and BMI increased from 21.9 kg/m2 to 23.0 kg/m2 after one year of treatment (p < 0.0001 for both). The proportion of underweight individuals decreased after one year of ETI therapy, from 9.3% to 1.9%, while the proportion of overweight or obese individuals increased from 8.3% to 22.9 % at the same time (p < 0.001). In relation to exacerbations, there is a significant increase in the number of patients who did not have any exacerbations after one year of treatment, which increased from 10.2% to 46.2% (p < 0.001), while the number of patients who had >4 exacerbations decreased significantly, from 40.7% to 1.9% (p < 0.001). FEV1% (forced expiratory volume) increased from 63.9 ± 20.9 to 76.8 ± 21.4 (p < 0.001) and the VR/TLC (residual volume/total lung capacity) value decreased from 45.1 ± 10.9 to 34.9 ± 6.2 (p < 0.001). The proportion with FEV1% > 80% increased from 23.1% before ETI therapy to 49.1% one year after ETI therapy. We performed multivariate mixed models to evaluate the evolution of BMI changes with time, accounting for repeated measures and for possible modifying factors. After the introduction of the triple therapy, patients included in the study had significant weight gain during the 12 months, and when including different covariates in the multivariate mixed model, we found that lower baseline BMI, lower baseline FEV1 and FVC (forced vital capacity), and higher VR/TLC value and higher number of exacerbations were associated with higher BMI changes over the study period.

CONCLUSIONS

CF patients treated with triple therapy experience significant weight gain, increasing the proportion of overweight patients. CF patients who experienced greater weight gain were those with worse BMI at the start of treatment, as well as patients with worse lung function and a greater number of exacerbations in the year before starting ETI therapy.

Improving growth in infants with CF

Cystic fibrosis (CF) results in chronic pulmonary infections, inflammation, pancreatic insufficiency, and multiple gastrointestinal manifestations. Malnutrition and poor growth are hallmarks of CF, and strongly associated with poor outcomes. Through newborn screening, many infants can be diagnosed within a few days of life, which allows for early initiation of nutritional counseling and close clinical follow-up. Obstacles to growth for infants with CF start in utero, as newborns with CF can have a lower birth weight than the general population. Improving infant growth has been linked to improved clinical outcomes and survival. It remains a top priority and challenge for caregivers and healthcare teams. An interdisciplinary approach, including registered dietitian and social work support, is essential to optimize health for infants with CF. Remaining barriers to normalcy include deficits in linear growth, lack of accurate nutrition biomarkers, persistence of inequities related to social determinant of health, particularly in the global CF community.

Premodulator microbiome alterations associated with postmodulator growth outcomes in pediatric cystic fibrosis: Can we predict outcomes?

OBJECTIVES

The gut microbiota plays an important role in childhood growth. Our longitudinal cohort includes children with cystic fibrosis (CwCF) treated with highly effective modulator therapy. We aimed to elucidate early premodulator microbial signatures associated with postmodulator weight for CwCF later in childhood.

METHODS

Stool samples were collected from CwCF at 13 days to 60 months. Metagenomic sequencing determined differentially abundant taxa. Children with body mass index or weight for length Z-scores within 1 standard deviation of the mean (SD) were considered normal weight, those >1 SD were classified as risk of overweight while children <1 SD were considered undernourished, although no CwCF met this latter criterion here. Multivariate regression models were applied to identify significant associations between metadata and microbial taxonomic relative abundances.

RESULTS

One hundred and eighty-nine stool samples were analyzed from 39 CwCF. We identified statistically significant differences in early microbiome patterns among those at risk of being overweight compared to those who were normal weight when adjusted for age, sex, CF mutation, and early feeding method. Early microbiome was a stronger driver of growth status than current modulator use. Among those at risk of overweight, several taxa that were consistently in lower abundance included Eggerthella lentha, Ruminococcus, Bacteroides, with increase in abundance of Bacteroides stercoris.

CONCLUSIONS

The early microbiome strongly predicts growth in the setting of modulator use for CwCF and we identify microbiome signatures associated with risk of being overweight. We highlight the possibility for interventions or early alternations to nutritional guidance for prevention of comorbid complications.

Evolution of nutritional management in children with cystic fibrosis - a narrative review

Nutrition has played a central role in the management and outcomes of people with cystic fibrosis (pwCF) since the 1970s. Advances in therapies and practices in recent decades have led to a significant change in the patient landscape with dramatic improvements in life expectancy, as well as quality of life, bringing with it new issues. Historically, cystic fibrosis was a condition associated with childhood and malnutrition; however, changes in patient demographics, nutritional assessment and fundamental nutritional management have evolved, and it has become an increasingly prevalent adult disease with new nutritional challenges, including obesity. This paper aims to describe these changes and the impact and challenges they bring for those working in this field. Nutritional professionals will need to evolve, adapt and remain agile to the wider range of situations and support required for a new generation of pwCF. Specialised nutrition support will continue to be required, and it will be additionally important to improve and optimise quality of life and long-term health.

Impact of elexacaftor/tezacaftor/ivacaftor on lipid and fat-soluble vitamin levels and association with body mass index

INTRODUCTION

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators improve gastrointestinal absorption of nutrients and may result in changes in body mass index (BMI), serum lipids, and fat-soluble vitamin levels. We hypothesized that serum lipids and vitamin levels would increase with CFTR modulator therapy and that greater increase in lipids and vitamin levels would be related to greater increase in BMI.

METHODS

A retrospective study was performed to evaluate the impact of elexacaftor/tezacaftor/ivacaftor (ETI) on nutritional parameters, serum lipids, and fat-soluble vitamin levels. Pre-ETI values (<2 years prior) and post-ETI values (>1 month after) were compared. Linear regression was used to evaluate whether change in BMI is associated with the change in lipid and/or vitamin levels and whether modulator duration is associated with the degree of rise in lipid and/or vitamin levels.

RESULTS

Adults and adolescents with CF (n = 137) were evaluated before and 31-300 days after starting ETI. Median BMI (adults 21.9 vs. 23.5 kg/m2 ; adolescents 48 vs. 63 percentile) increased after initiation of ETI. Total cholesterol (126 vs. 154 mg/dL), low-density lipoprotein cholesterol (63 vs. 78 mg/dL), non-high-density lipoprotein cholesterol (84 vs. 102 mg/dL), and high density lipoprotein cholesterol (43 vs. 49 mg/dL) increased after ETI, while triglycerides and very low density lipoprotein did not change. Median values for vitamin D (34.5 vs. 38.0 ng/mL) and vitamin A (40.1 vs. 47.9 µg/dL) increased, while vitamin E did not change significantly. There was no significant correlation between BMI change or duration of modulator therapy with vitamin levels or lipid changes.

CONCLUSION

After initiation of ETI therapy, serum lipids increased in our population, but most values remained within the normal range. Vitamins A and D levels increased post-ETI and no changes were noted in vitamin E. No significant correlation between the degree of BMI change and the magnitude of increase in lipids or vitamin levels was found.

ESPEN-ESPGHAN-ECFS guideline on nutrition care for cystic fibrosis

BACKGROUND

Nutritional status is paramount in Cystic Fibrosis (CF) and is directly correlated with morbidity and mortality. The first ESPEN-ESPGHAN-ECFS guidelines on nutrition care for infants, children, and adults with CF were published in 2016. An update to these guidelines is presented.

METHODS

The study was developed by an international multidisciplinary working group in accordance with officially accepted standards. Literature since 2016 was reviewed, PICO questions were discussed and the GRADE system was utilized. Statements were discussed and submitted for on-line voting by the Working Group and by all ESPEN members.

RESULTS

The Working Group updated the nutritional guidelines including assessment and management at all ages. Supplementation of vitamins and pancreatic enzymes remains largely the same. There are expanded chapters on pregnancy, CF-related liver disease, and CF-related diabetes, bone disease, nutritional and mineral supplements, and probiotics. There are new chapters on nutrition with highly effective modulator therapies and nutrition after organ transplantation.

Parental Feeding Style, Parenting Stress, and Child Mealtime Behaviors in Cystic Fibrosis

OBJECTIVE

Nutrition and weight gain significantly contribute to overall health outcomes in children with cystic fibrosis (CF). Strong emphasis is placed on these entities by the CF team, which can cause stress for parents and impact parent and child mealtime behaviors. The current study sought to investigate the relationship between parental feeding style, parenting stress, and parent and child mealtime behaviors in families of children with CF.

METHODS

Forty-five parents of a child with CF between the ages of 2 and 10 years were recruited during a CF clinic appointment. They completed surveys assessing child mealtime behaviors, parental feeding style, and parental stress. Medical data including body mass index (BMI) were collected from the medical record.

RESULTS

There was a significant difference in behavioral feeding scores based on feeding style (F3,41 = 13.48, p <.001), with authoritarian parents reporting significantly greater mealtime behavior problems than all other parents. There was also a significant difference in parenting stress based on parental feeding style (F3,41=4.11, p <.05), with authoritarian parents showing more stress than authoritative parents (Mdiff=23.70, p <.05). Correlation analyses showed a positive relationship between behavioral feeding problems and parent stress, r(45)=0.403; p <.01.

CONCLUSIONS

Data suggest parents using an authoritarian feeding style experience more stress and behavioral feeding problems than other parents. More feeding problems were also associated with more stress. Findings help determine how pediatric psychologists can intervene to support positive parenting behaviors that reduce children's mealtime behavior problems and parental stress, thus improving health outcomes in this vulnerable population.

Standards for the care of people with cystic fibrosis; establishing and maintaining health

This is the second in a series of four papers updating the European Cystic Fibrosis Society (ECFS) standards for the care of people with CF. This paper focuses on establishing and maintaining health. The guidance is produced using an evidence-based framework and with wide stakeholder engagement, including people from the CF community. Authors provided a narrative description of their topic and statements, which were more directive. These statements were reviewed by a Delphi exercise, achieving good levels of agreement from a wide group for all statements. This guidance reinforces the importance of a multi-disciplinary CF team, but also describes developing models of care including virtual consultations. The framework for health is reinforced, including the need for a physically active lifestyle and the strict avoidance of all recreational inhalations, including e-cigarettes. Progress with cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy is reviewed, including emerging adverse events and advice for dose reduction and interruption. This paper contains guidance that is pertinent to all people with CF regardless of age and eligibility for and access to modulator therapy.

Body mass index and nutritional intake following Elexacaftor/Tezacaftor/Ivacaftor modulator therapy in adults with cystic fibrosis

BACKGROUND

Elexacaftor/Tezacaftor/Ivacaftor (ETI) modulator therapy is often associated with increased body mass index (BMI) in people with cystic fibrosis (CF). This is thought to reflect improved clinical stability and increased appetite and nutritional intake. We explored the change in BMI and nutritional intake following ETI modulator therapy in adults with CF.

METHODS

Dietary intake, measured with myfood24®, and BMI were collected from adults with CF at baseline and follow-up as part of an observational study. Changes in BMI and nutritional intake in participants who commenced ETI therapy between time points were assessed. To contextualize findings, we also assessed changes in BMI and nutritional intake between study points in a group on no modulators.

RESULTS

In the pre and post ETI threapy group (n = 40), BMI significantly increased from 23.0 kg/m2 (IQR 21.4, 25.3) at baseline to 24.6 kg/m2 (IQR 23.0, 26.7) at follow-up (p<0.001), with a median of 68 weeks between time points (range 20-94 weeks) and median duration of ETI therapy was 23 weeks (range 7-72 weeks). There was a significant decrease in energy intake from 2551 kcal/day (IQR 2107, 3115) to 2153 kcal/day (IQR 1648, 2606), p<0.001. In the no modulator group (n = 10), BMI and energy intake did not significantly change between time points (p>0.05), a median of 28 weeks apart (range 20-76 weeks).

CONCLUSIONS

These findings tentatively suggest that the increase in BMI with ETI therapy may not simply be attributable to an increase in oral intake. Further exploration into the underlying aetiology of weight gain with ETI therapy is needed.

Evolving nutritional needs, obesity, and overweight status in cystic fibrosis

PURPOSE OF REVIEW

The nutritional landscape in cystic fibrosis has shifted dramatically in the era of CFTR modulator therapy. In this review, we will critically examine the literature on overweight and obesity in CF, current nutritional care unknowns and opportunities for further investigation or adaptation in clinical care.

RECENT FINDINGS

Results of clinical trial and real-world data reflect marked improvement in nutritional status and quality of life. Clinical outcomes including CF related diabetes and CF related liver disease appear positively impacted. Secondary impacts on cardiometabolic disease have been noted, especially in association with excessive weight gain.

SUMMARY

The prior approaches to optimizing nutrition in cystic fibrosis with caloric excess can likely be safely retired for many. As modulator access expands across the lifespan, a longitudinal focus on health maintenance should be considered.

Nutritional management of people living with cystic fibrosis throughout life and disease continuum: Changing times, new challenges

Cystic fibrosis (CF) is a genetic disease caused by mutations in the gene encoding for the ion channel cystic fibrosis transmembrane conductance regulator (CFTR). The management of CF disease has evolved in recent decades from treating downstream disease manifestations affecting the airways, the lungs and the gastrointestinal system to addressing the CFTR gene defect. The advent of CFTR modulators, which correct the functionality of the defective CFTR, contributes to reshaping the landscape of CF demographics, prognosis and therapies, including nutritional management. A spectrum of clinical manifestations is emerging within the same patient population where undernutrition and nutritional deficiencies coexist with excessive weight gain and metabolic derangements. Such contrasting presentations challenge current practices, require adjustments to traditional approaches, and involve more individualised interventions. This narrative review examines the current state of knowledge on the nutritional management of people living with cystic fibrosis from early life to adulthood in the era of CFTR modulation.

A new era in cystic fibrosis care: always changing and adapting

PURPOSE OF REVIEW

This review focuses on sharing the current and changing cystic fibrosis (CF) care model. This includes changes in CF care as a chronic disease with availability of new revolutionary, highly effective therapies as well as incorporation of shared decision-making, coproduction of care, quality improvement, telemedicine, and remote patient monitoring.

RECENT FINDINGS

Changes in the CF management, the CF patient population, and CF care team are described as well as how CF care has adapted to these changes.

SUMMARY

CF is a chronic, multisystem disease requiring a large specialized multidisciplinary care team for effective treatment. With improvements in CF care and new treatments, people with CF are living longer and healthier lives. As new issues arise, the CF team needs to adapt. This was highlighted by the introduction of highly effective cystic fibrosis transmembrane conductance regulator modulator therapy, which targets the cellular defect in CF, the COVID-19 pandemic, which lead to the incorporation of telehealth and remote patient monitoring into the CF care model, and the partnering with people with CF and families through shared decision-making and coproduction.

A paradigm shift in cystic fibrosis nutritional care: Clinicians' views on the management of patients with overweight and obesity

BACKGROUND

Overweight and obesity among people with cystic fibrosis (pwCF) has become more prevalent since the widespread adoption of CF transmembrane conductance regulator (CFTR) modulator therapies and presents a new challenge for nutritional care. We aimed to explore how clinicians working in CF care approach the management of adults with overweight and obesity.

METHODS

We conducted semi-structured interviews with n = 20 clinicians (n = 6 physiotherapists, n = 6 doctors and n = 8 dietitians) working in 15 adult CF centres in the United Kingdom. The interviews explored their perspectives and current practices caring for people with CF and overweight/obesity. Data were analysed using reflexive thematic analysis.

RESULTS

Four main themes were identified: 1) challenges of raising the topic of overweight and obesity in the CF clinic (e.g., clinician-patient rapport and concerns around weight stigma); 2) the changing landscape of assessment due to CF-specific causes of weight gain: (e.g., impact of CFTR modulators and CF legacy diet) 3) presence of clinical equipoise for weight management due to the lack of CF-specific evidence on the consequences of obesity and intentional weight loss (e.g., unclear consequences on respiratory outcomes and risk of weight related co-morbidities) and 4) opportunities for a safe, effective, and acceptable weight management treatment for people with CF (e.g., working collaboratively with current multidisciplinary CF care).

CONCLUSIONS

Approaching weight management in the CF setting is complex. Trials are needed to assess the equipoise of weight management interventions in this group and CF-specific issues should be considered when developing such interventions.

Hope in Every Breath: Navigating the Therapeutic Landscape of Cystic Fibrosis

Cystic fibrosis (CF) has long posed a complex challenge to medical science. Still, the tides are turning with remarkable progress in prognosis and demographics, thanks to cutting-edge medical management and treatment breakthroughs. It affects multiple systems, necessitating a comprehensive approach to its management. This article thoroughly reviews the latest advancements in CF treatment across three key areas: respiratory care, infection prevention, and pharmacological management. In respiratory care, emphasis is placed on airway clearance therapies and nebulized saline, while infection prevention strategies encompass hand hygiene, respiratory etiquette, and environmental cleaning and disinfection. Pharmacological management explores pancreatic enzyme replacement therapy (PERT), antimicrobial treatments, cystic fibrosis transmembrane regulator (CFTR) modulators, and promising gene therapies. Patient education and support are highlighted as crucial components of effective CF management, while mental health assessments are emphasized due to CF patients' susceptibility to anxiety and depression. This review highlights the tremendous progress made in the management of CF. Integrating early detection, infection prevention, pharmacological interventions, gene therapy, and patient support is revolutionizing the care and quality of life for individuals with CF.

Cystic Fibrosis: A Review

Importance

Cystic fibrosis, a genetic disorder defined by variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, affects more than 30 000 individuals in the US and approximately 89 000 worldwide. Absent or decreased function of the CFTR protein is associated with multiorgan dysfunction and shortened life expectancy.

Observations

CFTR is an anion channel in the apical membrane of epithelial cells. Loss of function leads to obstructed exocrine glands. Of people with cystic fibrosis in the US, approximately 85.5% have the gene variant F508del. Manifestations of cystic fibrosis in patients with the F508del gene variant begin in infancy with steatorrhea, poor weight gain, and respiratory symptoms (coughing, wheezing). As people with cystic fibrosis age, chronic respiratory bacterial infections cause loss of lung function and bronchiectasis. With the availability of universal newborn screening in multiple countries including the US, many people with cystic fibrosis are asymptomatic at diagnosis. With multidisciplinary care teams that included dietitians, respiratory therapists, and social workers, treatment of cystic fibrosis can slow disease progression. Median survival has improved from 36.3 years (95% CI, 35.1-37.9) in 2006 to 53.1 years (95% CI, 51.6-54.7) in 2021. Pulmonary therapies for patients with cystic fibrosis consist of mucolytics (eg, dornase alfa), anti-inflammatories (eg, azithromycin), and antibiotics (such as tobramycin delivered by a nebulizer). Four small molecular therapies, termed CFTR modulators, that facilitate CFTR production and/or function have received regulatory approval. Examples are ivacaftor and elexacaftor-tezacaftor-ivacaftor. For example, in patients with 1 F508del variant, the combination of ivacaftor, tezacaftor, and elexacaftor improved lung function from -0.2% in the placebo group to 13.6% (difference, 13.8%; 95% CI, 12.1%-15.4%) and decreased the annualized estimated rate of pulmonary exacerbations from 0.98 to 0.37 (rate ratio, 0.37; 95% CI, 0.25-0.55). Improved respiratory function and symptoms have lasted up to 144 weeks in postapproval observational studies. An additional 177 variants are eligible for treatment with the elexacaftor-tezacaftor-ivacaftor combination.

Conclusion

Cystic fibrosis affects approximately 89 000 people worldwide and is associated with a spectrum of disease related to exocrine dysfunction, including chronic respiratory bacterial infections and reduced life expectancy. First-line pulmonary therapies consist of mucolytics, anti-inflammatories, and antibiotics, and approximately 90% of people with cystic fibrosis who are 2 years or older may benefit from a combination of ivacaftor, tezacaftor, and elexacaftor.

Cystic Fibrosis-Related Diabetes Workshop: Research Priorities Spanning Disease Pathophysiology, Diagnosis, and Outcomes

Cystic fibrosis (CF) is a recessive disorder arising from mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. CFTR is expressed in numerous tissues, with high expression in the airways, small and large intestine, pancreatic and hepatobiliary ducts, and male reproductive tract. CFTR loss in these tissues disrupts regulation of salt, bicarbonate, and water balance across their epithelia, resulting in a systemic disorder with progressive organ dysfunction and damage. Pancreatic exocrine damage ultimately manifests as pancreatic exocrine insufficiency that begins as early as infancy. Pancreatic remodeling accompanies this early damage, during which abnormal glucose tolerance can be observed in toddlers. With increasing age, however, insulin secretion defects progress such that CF-related diabetes (CFRD) occurs in 20% of teens and up to half of adults with CF. The relevance of CFRD is highlighted by its association with increased morbidity, mortality, and patient burden. While clinical research on CFRD has greatly assisted in the care of individuals with CFRD, key knowledge gaps on CFRD pathogenesis remain. Furthermore, the wide use of CFTR modulators to restore CFTR activity is changing the CFRD clinical landscape and the field's understanding of CFRD pathogenesis. For these reasons, the National Institute of Diabetes and Digestive and Kidney Diseases and the Cystic Fibrosis Foundation sponsored a CFRD Scientific Workshop, 23-25 June 2021, to define knowledge gaps and needed research areas. This article describes the findings from this workshop and plots a path for CFRD research that is needed over the next decade.

Cystic Fibrosis-Related Diabetes Workshop: Research Priorities Spanning Disease Pathophysiology, Diagnosis, and Outcomes

Cystic fibrosis (CF) is a recessive disorder arising from mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. CFTR is expressed in numerous tissues, with high expression in the airways, small and large intestine, pancreatic and hepatobiliary ducts, and male reproductive tract. CFTR loss in these tissues disrupts regulation of salt, bicarbonate, and water balance across their epithelia, resulting in a systemic disorder with progressive organ dysfunction and damage. Pancreatic exocrine damage ultimately manifests as pancreatic exocrine insufficiency that begins as early as infancy. Pancreatic remodeling accompanies this early damage, during which abnormal glucose tolerance can be observed in toddlers. With increasing age, however, insulin secretion defects progress such that CF-related diabetes (CFRD) occurs in 20% of teens and up to half of adults with CF. The relevance of CFRD is highlighted by its association with increased morbidity, mortality, and patient burden. While clinical research on CFRD has greatly assisted in the care of individuals with CFRD, key knowledge gaps on CFRD pathogenesis remain. Furthermore, the wide use of CFTR modulators to restore CFTR activity is changing the CFRD clinical landscape and the field's understanding of CFRD pathogenesis. For these reasons, the National Institute of Diabetes and Digestive and Kidney Diseases and the Cystic Fibrosis Foundation sponsored a CFRD Scientific Workshop, 23-25 June 2021, to define knowledge gaps and needed research areas. This article describes the findings from this workshop and plots a path for CFRD research that is needed over the next decade.

The impact of elexacaftor/tezacaftor/ivacaftor on body composition in a small cohort of youth with cystic fibrosis

BACKGROUND

The effects of elexacaftor-tezacaftor-ivacaftor (ETI) on body composition in people with CF (pwCF) are unknown.

METHODS

Dual-energy X-ray absorptiometry fat-free mass and fat mass adjusted for height (FMI) as well as oral glucose tolerance test derived measures of insulin secretion and sensitivity were compared before and after ETI initiation in eight pwCF.

RESULTS

Patients median age: 22 years interquartile range (IQR: 16-28), 87.5% male, median time on ETI:11 months. Weight z-score increased from -0.52 to 0.18 (p = 0.014); FMI increased from 4.12 to 6.29 (p = 0.014). Insulin secretion (C pep iAUC/Gluc iAUC) increased from 8.71 to 14.21 (p = 0.021), insulin resistance (HOMA2 IR) increased from 0.73 to 1.25 (p = 0.014) and insulin sensitivity decreased (Matsuda) 8.88 to 5.58 (p = 0.036).

CONCLUSIONS

ETI resulted in increased weight and fat mass. BMI and muscle mass did not change. Both insulin secretion and insulin resistance increased. Longer-term metabolic consequences of ETI need further investigation.

Nutritional Status and Circulating Levels of Fat-Soluble Vitamins in Cystic Fibrosis Patients: A Cohort Study and Evaluation of the Effect of CFTR Modulators

BACKGROUND

Improved therapy in CF has led to an overall improvement in nutritional status. The objectives of our study are: to cross-sectionally assess nutritional status and serum levels of fat-soluble vitamins; to retrospectively evaluate the efficacy of modulators on nutritional status and fat-soluble vitamin levels.

METHODS

In patients younger than 2 years of age, we evaluated growth, in patients aged 2-18 years, we assessed BMI z-scores, and in adults, we assessed absolute BMI values. Levels of 25(OH)D, vitamins A, and E were measured.

RESULTS

A cross-sectional analysis was conducted on 318 patients, 109 (34.3%) with pancreatic sufficiency. Only three patients were under 2 years old. In 135 patients aged 2-18 years, the median BMI z-score was 0.11, and 5 (3.7%) patients had malnutrition (z-score ≤ 2SD). In 180 adults, the median BMI was 21.8 kg/m². Overall, 15 (13.7%) males (M) and 18 (25.3%) females (F) were underweight (18 < BMI > 20); 3 (2.7%) M and 5 (7.0%) F had a BMI < 18. Suboptimal 25(OH)D levels were found in patients with pancreatic insufficiency. The prevalence of deficiency of vitamins A and E is low. After one year of treatment with modulators, the increase in BMI was more consistent (M: 1.58 ± 1.25 kg/m² F: 1.77 ± 1.21 kg/m²) in elexacaftor/tezacaftor/ivacaftor (ETI)-treated patients compared with other modulators, with a significant increase in levels of all fat-soluble vitamins.

CONCLUSIONS

Malnutrition is present in a limited number of subjects. The prevalence of subjects with suboptimal 25(OH)D levels is high. ETI showed a beneficial effect on nutritional status and circulating levels of fat-soluble vitamins.

Nutritional and metabolic management for cystic fibrosis in a post-cystic fibrosis transmembrane conductance modulator era

PURPOSE OF REVIEW

The introduction of highly effective cystic fibrosis transmembrane conductance regulator modulators has resulted in a paradigm shift towards treating underlying cause of cystic fibrosis (CF) rather than the ensuing complications. In this review, we will describe the impact of these small molecules on growth, nutrition, and metabolic status in people with CF (pwCF).

RECENT FINDING

Results of clinical trials and real world data demonstrate that these small molecules are having a significant impact of on augmenting body weight, improving nutritional status and reducing gastrointestinal symptom burden. Early treatment can also positively impact on pancreatic endocrine and exocrine function.

SUMMARY

Nutritional and metabolic management of pwCF needs to change in order to maximize long term health and avoid future complications relating to obesity and increased cardiovascular risk. Longitudinal registry studies will be key to improve our understanding of the longer-term outcome of these new therapies.

Serum kisspeptin and proopiomelanocortin in cystic fibrosis: a single study

The determination of hormonal biomarkers is of increasing interest in many diseases, including cystic fibrosis (CF). Hormones that have not been estimated and described so far in CF include kisspeptin (KISS) and proopiomelanocortin (POMC), which are involved in the regulation of many processes, including appetite and fertility. Therefore, the aim of our study was to estimate the level of KISS and POMC in sera from CF patients and to determine the correlation between these hormones and clinical parameters. For this purpose, we estimated the levels of KISS and POMC in 38 CF patients and 16 healthy participants with enzyme-linked immunosorbent assay. We found significantly reduced levels of KISS and POMC in people with CF compared to healthy subjects (1.76 ± 0.46 vs. 2.27 ± 0.56 ng/mL, p < 0.05 and 6.25 ± 4.36 vs. 14.74 ± 6.24 ng/mL, p < 0.001, respectively). Furthermore, the level of both hormones was negatively correlated with age. The hormones studied did not correlate with the results of spirometry and each other. Thus, decreased KISS and POMC levels may be associated with lower body weight and delayed puberty in patients with CF.

A Cross-Sectional Study of the Marital Attitudes of Pregnant Women at Risk for Cystic Fibrosis and Psychological Impact of Prenatal Screening

Cystic fibrosis (CF) is one of the most frequent genetic disorders in those with Northern European ancestry. Prenatal testing for cystic fibrosis may be used to plan and prepare for the birth of a child with the disease or to determine whether to terminate the pregnancy. The accessibility of prenatal detection for women with a high genetic risk of delivering a child with cystic fibrosis is determined by CF carriers and those affected by the disease. Moreover, prenatal testing for CF is mainly dependent on invasive diagnostic tests that can influence the mental health of the pregnant woman, and it is assumed that the birth of a CF child will have a serious influence on the couple's subsequent family planning and marital behavior. The purpose of this research was to examine the marital attitudes of women at risk for cystic fibrosis and the psychological effect of screening for CF among pregnant women. The study followed a cross-sectional design with five questionnaires comprising Prenatal Attachment Interview (PAI), Maternal Antenatal Attachment Scale (MAAS), Pregnancy-Related Anxiety Questionnaire (PRAQ-R2), the Prenatal Psychosocial Profile (PPP), and the Marital Intimacy Questionnaire (MIQ). A total of 84 pregnant women were included in the "carriers" group for CFTR and 91 in the "non-carrier" group. CFTR-carrier mothers were likely to be more affectionate to the fetus, with better maternal-fetal quality and intensity of attachment. The same group of pregnant women was less scared of giving birth or worried about bearing a physically or mentally handicapped child compared to women who were expecting the prenatal diagnosis test for being at risk of delivering a newborn with malformations. CFTR-carrier pregnant women did not score significantly different results in the Prenatal Psychosocial Profile regarding stress levels, social support, and self-esteem. It was also found that intimacy and consensus problems inside the marriage were significantly more often experienced by CFTR carriers. Based on the current findings, it is likely that CFTR-carrier mothers have a better perception of the possible pregnancy outcomes by knowing their abnormal gene carrier status. Therefore, the psychological impact of invasive diagnostic tests is lower in this category compared with those who are unaware of the possible pregnancy outcomes. However, we promote a future analysis for pregnant women with moderate risk of giving birth to a child with single-gene mutations such as cystic fibrosis or other congenital malformations that undergo noninvasive prenatal diagnosis tests, as they become more accurate and might cause lower pre-diagnosis stress levels.

Eating Disorders and Disordered Eating Behaviors in Cystic Fibrosis: A Neglected Issue

As with the majority of chronic diseases having specific nutrition recommendations, in cystic fibrosis (CF), the emphasis placed on patients regarding their diet and ideal body weight status often increases the risk of developing disordered eating behaviors and by inference, eating disorders (EDs). Body weight appears to be an important concern for patients with CF, with many patients struggling to lose weight. Between sexes, women appear more preoccupied with dieting compared to men, but exhibit a better body image, mainly due to their preference for a lower weight. Several comorbidities appear to change these dynamics, and visibly apparent factors, including scars, ports, and tubes, and the need for supplementary oxygen supply, may also influence body image perception. Disordered eating is usually initiated during a bout of pulmonary infection, with the patient feeling unwell to eat. Regarding the prevalence of EDs, research appears conflicting on whether it is higher among individuals with a CF diagnosis or not. As for comorbidities, anxiety and depression consist of the most common psychiatric diagnoses in CF, also greatly prevalent in EDs. Despite the plethora of studies, non-specific CF tools, small samples, and lack of data regarding important outcomes, including lung health, indicate the need for more research.