The Impact of Highly Effective CFTR Modulators on Growth and Nutrition Status

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.

A review of proton pump inhibitor use in cystic fibrosis and considerations for deprescribing

Use of proton-pump inhibitors (PPIs) is common among people with cystic fibrosis (pwCF) both for the management of suspected GERD, as well as pancreatic enzyme replacement therapy augmentation. Despite their use, limited data exist to demonstrate a clinically significant impact of PPIs on key endpoints in pwCF. Furthermore, the advent of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy may modify the need for use. These notions, coupled with the potential for adverse outcomes associated with long-term PPI use in pwCF, should facilitate re-evaluation of long-term PPI use in pwCF and promote potential deprescribing. Despite limited data on PPI deprescribing in pwCF, it intuitively mirrors the existing guidance in adults in the general population, but with added consideration given to tapering strategy, and monitoring for CF-specific outcomes such as nutritional and respiratory status. The development of a monitoring and re-initiation plan is key to reducing deprescribing inertia. This review aims to summarize the evidence that details the concern for long-term use of PPIs and provide CF clinicians with rationale and guidance on how to approach deprescribing in their practice.

Prevalence of psychotropic medication dispensing to people living with cystic fibrosis in Australia: 2013-2022

OBJECTIVE

People living with cystic fibrosis (PwCF) are at increased risk of mental health conditions. There is little evidence addressing psychotropic medication use in PwCF. This study aimed to estimate the dispensing prevalence of antidepressant, anxiolytic, antipsychotic, psychostimulant, and hypnotic/sedative medication in PwCF in Australia between 2013 and 2022.

METHOD

A 10% random sample of Australian Pharmaceutical Benefits Scheme data was used to identify PwCF and their medications between 2013 and 2022. Annual prevalence of psychotropic medication dispensing was estimated using a 3-year rolling average, stratified by sex, age, and medication class.

RESULTS

Psychotropic medications were dispensed to 206/478 (41.3%) PwCF. Antidepressant and anxiolytic dispensing prevalence was highest in adult females, increasing from 201 5 by 50% to their peak in 2021 (antidepressants 36.8%; anxiolytics 12.3%). Psychostimulant prevalence was highest in adolescent males and increased over three-fold during the study period from 3.6% to 13.2%. The prevalence of antipsychotic medication was lower than other classes with adult females having the highest prevalence (3.1% and 5.8% in 201 5 and 2022 respectively). Hypnotic/sedative medications remained consistently low or decreased in all groups except male children, where it increased from 0.6% to 2.8% from 201 5 to 2022.

CONCLUSION

Psychotropic medication use is higher among Australian PwCF compared to the general population, with varying prevalence across age and sex groups. This is of interest due to complexities with CF comorbidities and potential medication influences and interactions. Future studies should investigate the reasons for psychotropic use disparities within PwCF with the aim to establish targeted guidelines and optimize outcomes.

Cystic fibrosis hepatobiliary involvement: an update on imaging in diagnosis and monitoring

Analysis of the liver using imaging for persons with cystic fibrosis (CF) continues to evolve as new medical therapies are developed improving and extending life. In the 2010s, therapies targeted at modulating protein folding became available to those with CF. Therapeutic options have continued to expand, now providing both correction of protein folding and stabilization for most gene mutations that code for the CF transmembrane receptor protein (CFTR). Today, approximately 80% of persons with CF are eligible for highly effective modulator therapy. With these advancements, the impact of CF on the liver has become more complex, adding metabolism of CFTR modulators to intrinsic CF hepatobiliary involvement (CFHBI) and adding not previously appreciated vascular changes within the liver due to increased longevity in persons with CF. A combination of serum biomarkers and imaging is needed to add clarity to the diagnosis and monitoring of the severity of liver disease. A substantial portion of persons with CF will develop at least CFHBI and a subset will develop advanced cystic fibrosis-associated liver disease (aCFLD); therefore, diagnosis and monitoring need to begin in childhood. In this review, we cover the use of and need for imaging, including elastography, ultrasound, and magnetic resonance imaging (MRI), in diagnosing and monitoring CFHBI and its associated complications.

Impaired intestinal free fatty acid transport followed by chylomicron malformation, not pancreatic insufficiency, cause metabolic defects in cystic fibrosis

Intestinal disease is one of the earliest manifestations of cystic fibrosis (CF) in children and is closely tied to deficits in growth and nutrition, both of which are directly linked to future mortality. Patients are treated aggressively with pancreatic enzyme replacement therapy and a high-fat diet to circumvent fat malabsorption, but this does not reverse growth and nutritional defects. We hypothesized that defects in chylomicron production could explain why CF body weights and nutrition are so resistant to clinical treatments. We used gold standard intestinal lipid absorption and metabolism approaches, including mouse mesenteric lymph cannulation, in vivo chylomicron secretion kinetics, transmission electron microscopy, small intestinal organoids, and chylomicron metabolism assays to test this hypothesis. In mice expressing the G542X mutation in cystic fibrosis transmembrane conductance regulator (CFTR-/- mice), we find that defective FFA trafficking across the epithelium into enterocytes drives a chylomicron formation defect. Furthermore, G542X mice secrete small, triglyceride-poor chylomicrons into the lymph and blood. These defective chylomicrons are cleared into extraintestinal tissues at ∼10-fold faster than WT chylomicrons. This defect in FFA absorption resulting in dysfunctional chylomicrons cannot be explained by steatorrhea or pancreatic insufficiency and is maintained in primary small intestinal organoids treated with micellar lipids. These studies suggest that the ultrahigh-fat diet that most people with CF are counselled to follow may instead make steatorrhea and malabsorption defects worse by overloading the absorptive capacity of the CF small intestine.

Nutritional Trends in Cystic Fibrosis: Insights from the Italian Cystic Fibrosis Patient Registry

Background: Over the past decades, efforts have been made to improve the nutritional well-being of people with cystic fibrosis (pwCF). Due to the correlation observed between nutritional indices and lung function, prevailing recommendations consistently advocate for BMI percentile goals at or above the 50th percentile in pwCF. Recent global trends show a notable increase in overweight and obese statuses among pwCF. This study aims to explore the nutritional status of Italian pwCF. Methods: Data from the Italian CF Patient's Registry were analysed to assess the proportion of individuals categorized as underweight, target weight, overweight, and obese from 2010 to 2021. Patient-level comparison data from 2021 were also examined to identify the potential determinants of overweight and obesity. Results: Analysis spanning 2010 to 2021 reveals a decrease of approximately 40% in underweight status among adults, while the proportion of malnourished patients younger than 18 years remained stable. Conversely, there was a substantial increase of over 70% in overweight status and over 85% in obesity among adults, with minor fluctuations observed among children and adolescents. Patient factors associated with increased obesity incidence included age older than 45 years, male gender, pancreatic sufficiency, possession of at least one CFTR variant conferring residual function, ppFEV1 > 90, and lower prevalence of Pseudomonas aeruginosa colonization. Conclusions: Our study confirms the evolving nutritional status landscape among Italian adult pwCF, with a significant shift towards overweight and obesity over the past decade. These trends highlight the need for proactive measures within CF standards of care to adapt and address the changing needs of patients.

Ventromedial hypothalamic nucleus subset stimulates tissue thermogenesis via preoptic area outputs

OBJECTIVE

Hypothalamic signals potently stimulate energy expenditure by engaging peripheral mechanisms to restore energy homeostasis. Previous studies have identified several critical hypothalamic sites (e.g. preoptic area (POA) and ventromedial hypothalamic nucleus (VMN)) that could be part of an interconnected neurocircuit that controls tissue thermogenesis and essential for body weight control. However, the key neurocircuit that can stimulate energy expenditure has not yet been established.

METHODS

Here, we investigated the downstream mechanisms by which VMN neurons stimulate adipose tissue thermogenesis. We manipulated subsets of VMN neurons acutely as well as chronically and studied its effect on tissue thermogenesis and body weight control, using Sf1Cre and Adcyap1Cre mice and measured physiological parameters under both high-fat diet and standard chow diet conditions. To determine the node efferent to these VMN neurons, that is involved in modulating energy expenditure, we employed electrophysiology and optogenetics experiments combined with measurements using tissue-implantable temperature microchips.

RESULTS

Activation of the VMN neurons that express the steroidogenic factor 1 (Sf1; VMNSf1 neurons) reduced body weight, adiposity and increased energy expenditure in diet-induced obese mice. This function is likely mediated, at least in part, by the release of the pituitary adenylate cyclase-activating polypeptide (PACAP; encoded by the Adcyap1 gene) by the VMN neurons, since we previously demonstrated that PACAP, at the VMN, plays a key role in energy expenditure control. Thus, we then shifted focus to the subpopulation of VMNSf1 neurons that contain the neuropeptide PACAP (VMNPACAP neurons). Since the VMN neurons do not directly project to the peripheral tissues, we traced the location of the VMNPACAP neurons' efferents. We identified that VMNPACAP neurons project to and activate neurons in the caudal regions of the POA whereby these projections stimulate tissue thermogenesis in brown and beige adipose tissue. We demonstrated that selective activation of caudal POA projections from VMNPACAP neurons induces tissue thermogenesis, most potently in negative energy balance and activating these projections lead to some similar, but mostly unique, patterns of gene expression in brown and beige tissue. Finally, we demonstrated that the activation of the VMNPACAP neurons' efferents that lie at the caudal POA are necessary for inducing tissue thermogenesis in brown and beige adipose tissue.

CONCLUSIONS

These data indicate that VMNPACAP connections with the caudal POA neurons impact adipose tissue function and are important for induction of tissue thermogenesis. Our data suggests that the VMNPACAP → caudal POA neurocircuit and its components are critical for controlling energy balance by activating energy expenditure and body weight control.

Faecal lipid profile as a new marker of fat maldigestion, malabsorption and microbiota

BACKGROUND

Fat malabsorption in children with cystic fibrosis (CF) leads to poor nutritional status and altered colonic microbiota. This study aimed at establishing the faecal lipid profile in children with CF, and exploring associations between the faecal lipidome and microbiota.

METHODS

Cross-sectional observational study with children with CF and an age-matched control group. Faecal lipidome was analysed by UHLC-HRMS and microbiota profiling by 16S rRNA amplicon sequencing.

RESULTS

Among 234 identified lipid species, five lipidome clusters (LC) were obtained with significant differences in triacylglycerols (TG), diacylglycerols (DG), monoacylglycerols (MG) and fatty-acids (FA): LC1 subjects with good digestion and absorption: low TG and low MG and FA; LC2 good digestion and poor absorption: low TG and high MG and FA; LC3 Mild digestion and poor absorption: intermediate TG and high MG and FA; LC4 poor digestion and absorption: high TG and high MG and FA; LC5 outliers. Bacteroidota and Verrucomicrobiota decreased over LC1-LC4, while Proteobacteria increased. Nutritional status indicators were significantly higher in LC1 and decreased over LC2-LC4.

CONCLUSION

Assessing faecal lipidome may be relevant to determine how dietary lipids are digested and absorbed. This new evidence might be a method to support targeted nutritional interventions towards reverting fat maldigestion or malabsorption.

IMPACT

Lipidomic analysis enabled the identification of the lipid species related to maldigestion (triglycerides) or malabsorption (monoglycerides and fatty acids). Children with cystic fibrosis can be grouped depending on the faecal lipidome profile related to dietary fat maldigestion or malabsorption. The lipidome profile in faeces is related to the composition of microbiota and nutritional status indicators.

Changes in fecal lipidome after treatment with ivacaftor without changes in microbiome or bile acids

BACKGROUND

Alterations in gastrointestinal health are prominent manifestations of cystic fibrosis (CF) and can independently impact pulmonary function. Ivacaftor has been associated with robust improvements in pulmonary function and weight gain, but less is known about the impact of ivacaftor on the fecal microbiome, lipidome, and bile acids.

METHODS

Stool samples from 18 patients with CF and gating mutations (ages 6-61 years, 13 pancreatic insufficient) were analyzed for fecal microbiome and lipidome composition as well as bile acid concentrations at baseline and after 3 months of treatment with ivacaftor. Microbiome composition was also assessed in a healthy reference cohort.

RESULTS

Alpha and beta diversity of the microbiome were different between CF and reference cohort at baseline, but no treatment effect was seen in the CF cohort between baseline and 3 months. Seven lipids increased with treatment. No differences were seen in bile acid concentrations after treatment in CF. At baseline, 403 lipids and unconjugated bile acids were different between pancreatic insufficient (PI-CF) and sufficient (PS-CF) groups and 107 lipids were different between PI-CF and PS-CF after 3 months of treatment.

CONCLUSIONS

The composition and diversity of the fecal microbiome were different in CF as compared to a healthy reference, and did not change after 3 months of ivacaftor. We detected modest differences in the fecal lipidome with treatment. Differences in lipid and bile acid profiles between PS-CF and PI-CF were attenuated after 3 months of treatment.

Developing a nutrition screening tool for children with cystic fibrosis ages 0 to 2 years: Children with cystic fibrosis nutrition screening tool

BACKGROUND

For children with cystic fibrosis (CF), achieving and maintaining optimal growth by the age of 2 years is critical for future health outcomes. A standardized nutrition screening is needed to identify growth problems, enable timely interventions, and improve nutritional outcomes for children (0 to 2 years) with CF. The purpose of this study was to develop a nutrition screening tool for children (0 to 2 years) with CF to identify nutrition risk at every clinical encounter.

METHODS

A retrospective cross-sectional study was used to develop a nutrition screening tool to determine if nutrition interventions needed to change (at-risk) or continue (not at-risk). Retrospective data for pertinent nutrition factors were collected for 99 children attending an accredited CF clinic. The nutrition factors were compared to a dietitian assessment. A stepwise discriminant analysis determined weight-for-age (WFA) and weight-for-length (WFL) z-scores were significant. Then anthropometric data and corresponding dietitian assessment results were collected for children with CF attending two other accredited CF clinics (n = 29, n = 30). Discriminant analysis was used to determine sensitivity and specificity of the nutrition factors and to create a nutrition screening tool equation.

RESULTS

The nutrition screening model that included WFA z-score, LFA z-score, WFL z-score, and weight change velocity adequacy determined nutrition risk the best. The sensitivity was 89.7 %, specificity 83.2 %, NPV 93.3 %, and PPV 75.4 % for this model.

CONCLUSION

The nutrition screening tool equation developed in this study standardizes the process to identify children (0 to 2 years) with CF at nutrition risk. Further validation is needed.

Improved Nutritional Outcomes and Gastrointestinal Symptoms in Adult Cystic Fibrosis Patients Treated with Elexacaftor/Tezacaftor/Ivacaftor

INTRODUCTION

Cystic fibrosis transmembrane conductance regulator modulator therapy improves nutritional status and quality of life. Clinical trials have shown pancreatic insufficiency conversion, mostly in pediatric patients treated with ivacaftor. Studies with elexacaftor/tezacaftor/ivacaftor (ETI) in older patients have not suggested restoration of exocrine pancreas function, but quality data in adults are lacking. Our aim was to show the effect of ETI in adults with cystic fibrosis (CF) on nutritional status and digestive function. We hypothesized improvement of nutritional parameters and gastrointestinal symptoms, reduction of pancreatic enzyme replacement therapy, but uncertain improvement in exocrine pancreatic function.

METHODS

We prospectively enrolled adults with CF treated with ETI from August 2021 to June 2022. We measured anthropometric parameters, laboratory nutritional markers, change of fecal elastase, pancreatic enzymes replacement therapy needs, and gastrointestinal symptoms.

RESULTS

In the cohort of 29 patients (mean age 29.1 years), 82.8% suffered exocrine pancreatic insufficiency. After ETI, mean BMI increased by 1.20 kg/m2 (p < 0.001), mean body weight by 3.51 kg (p < 0.001), albumin by 2.81 g/L, and prealbumin by 0.06 (both p < 0.001). Only 1 patient, initially pancreatic insufficient (4.5%, p < 0.001), developed pancreatic sufficiency, indicated by increased fecal elastase from 45 μg/g to 442.1 μg/g. Mean change in lipase substitution decreased by 1,969 units/kg/day (p < 0.001) and stools frequency by 1.18 per day (p < 0.001).

CONCLUSION

Our data suggest increased nutritional parameters, lower pancreatic substitution requirements, and improved defecation in adult CF patients on ETI. Improvement in exocrine pancreatic function might be mutation-specific and needs further study.

The Changing Landscape of Treatment for Cystic Fibrosis Related Diabetes

Objective

Patients with Cystic Fibrosis related diabetes [CFRD] are treated with insulin and high calorie diets to maintain body mass. The combined CFTR modulator elexacaftor/tezacaftor/ivacaftor [ETI] decreases pulmonary exacerbations and improves nutritional status. We reviewed the effects of ETI on BMI, HbA1c and diabetes regimen in patients with CFRD over a period of three years.

Methods

Data of previously CFTR-modulator-naïve patients with CFRD and pancreatic insufficiency on ETI therapy were retrieved from an electronic health record database. Patients were followed for a mean duration of 2.7 ± 0.8 years after ETI initiation. Data pertaining to weight, BMI, HbA1c and diabetes regimen were collected at 6 months, 12 months, 2 years and at 3 years post-ETI initiation. Patients were then dichotomized based on their baseline BMI into a low BMI group and an "at target" BMI group. The effects of ETI on changes in weight, BMI, A1c and diabetes regimen were compared in both groups over a period of three years.

Results

Twenty-seven patients with CFRD (15 men/12 women), age 30.6 ± 11.5 (SD) years, BMI 22.4 ± 4.0 kg/m2, were included. Fifteen patients had low BMI (<22 kg/m2 for women, <23 kg/m2 for men) and 12 patients had at target BMI (≥22 kg/m2for women, ≥BMI 23 kg/m2 for men). Patients with low BMI had an increase in their BMI from 19.5 ± 1.7 to 21.4 ± 2.2 kg/m2 at one year (p = 0.002), and 21.8 ± 1.8 kg/m2 at three years (p = 0.004) after ETI initiation. Four patients (out of 15) in the low BMI group had achieved normal BMI by the end of study follow up. There was no change in weight in the at target BMI group. HbA1c and basal insulin requirements did not change in either group. Five patients started non-insulin therapies.

Conclusion

BMI increased after ETI therapy in CFRD patients with low BMI, but not in those with at target BMI. The use of non-insulin therapies is increasing in CFRD and should be evaluated in future studies.

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.

Impact of CFTR modulators on exercise capacity in adolescents with cystic fibrosis

Background

Exercise capacity is an independent predictor of clinical worsening in cystic fibrosis (CF). There is limited evidence of the impact of cystic fibrosis transmembrane conductance regulator (CFTR) modulators on exercise capacity in children with CF. The aim of the present study was to assess the impact of CFTR modulators on exercise capacity in a cohort of adolescents with CF.

Methods

A prospective single-centre cohort study was carried out. Cardiopulmonary exercise testing (CPET) was performed at baseline, prior to starting Symkevi or Kaftrio and between 4 and 8 months after starting treatment.

Results

19 adolescents with CF had CPET performed prior to and after CFTR modulator treatment, between December 2019 and March 2022. Breathing reserve improved in the whole cohort, with greater improvement in the modulator-naïve patients after starting treatment with Kaftrio. There was no improvement in peak oxygen uptake and anaerobic threshold after 4 to 8 months of treatment with CFTR modulators.

Conclusion

Exercise testing with CPET can be used as an additional tool to monitor response to CFTR modulators. Breathing reserve on CPET may provide a surrogate marker to monitor the improvement in CF lung disease with CFTR modulator treatment.

A Cross-Sectional Study of Pediatric Feeding Disorder in Children with Cystic Fibrosis

BACKGROUND

The exact prevalence of feeding problems in children with cystic fibrosis (CF) is unknown. Pediatric feeding disorder (PFD) encompasses poor oral intake with associated medical, nutrition, psychosocial, or feeding skill dysfunction. We hypothesized that PFD is common in CF and aimed to categorize feeding dysfunction across various domains in children with CF.

METHODS

An observational cross-sectional study was conducted in children with CF. Data collected included anthropometrics, nutrition data (including need for tube feeding/enteral nutrition [EN] or high-energy beverages, dietary diversity), feeding skills (Pediatric version of the Eating Assessment tool [pEAT]), and psychosocial function (About Your Child's Eating questionnaire [AYCE] in children 2-17 years of age/Behavioral Pediatric Feeding Assessment Scale [BPFAS] in children 12-23 months of age). PFD was defined as poor oral intake with: (a) pEAT score > 5; and/or (b) AYCE or BPFAS score > 2 standard deviation of normative controls; and/or (c) nutrition dysfunction (body mass index/weight-for-length z score < -1 and/or preference of oral high energy beverages or dependence on EN and/or decreased dietary diversity).

RESULTS

Of 103 children in the study, 62 (60.1%) had PFD, 7 children (6.8%) were malnourished, 10 needed EN (9.7%), and 30 (29.1%) needed oral high-energy beverages. Dietary diversity was decreased in 42 children (41.5%), 1 child had feeding skill dysfunction, and 11 (10.8%) met criteria for psychosocial dysfunction.

CONCLUSION

Almost 2/3rd of children with CF have PFD and many have poor dietary diversity. A significant percentage of children rely on EN and oral supplements, but psychosocial dysfunction is less prevalent.

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.

Impact of elexacaftor/tezacaftor/ivacaftor on fat-soluble vitamin levels in children with cystic fibrosis

BACKGROUND

Children with cystic fibrosis are at risk of fat-soluble vitamin deficiency. CFTR modulators positively effect nutritional status. This study aimed to assess changes in serum vitamins A, D & E after starting ETI therapy to ensure levels were not abnormally high.

METHODS

Retrospective review of annual assessment data over 3½ years, before and after starting ETI in a specialist paediatric CF centre, including vitamin levels.

RESULTS

54 eligible patients were included, aged 5-15 yrs (median age 11.5). Median time to post measurements was 171 days. Median vitamin A was increased (1.38 to 1.63 µmol/L, p<0.001). Three patients (6%) had high vitamin A post-ETI, compared with none at baseline; and 2 (4%) had low levels compared to 4 (8%) at baseline. No changes in vitamins D&E.

CONCLUSIONS

This study found increased vitamin A, sometimes to high levels. We recommend testing levels within 3 months of starting ETI.

CT imaging shows specific pancreatic abnormalities in persons with cystic fibrosis related diabetes

Cystic fibrosis related diabetes (CFRD) is observed in 20-50% of adults with cystic fibrosis (CF). Pancreas abnormalities on imaging, e.g. pancreas lipomatosis, are frequent in subjects with CF. We hypothesized that specific abnormalities may characterize patients with CFRD. We performed a retrospective study comparing the computed tomography (CT) of participants with CF with or without diabetes ("CFRD" and "CF control" groups). We classified the pancreas on imaging according to 3 categories: normal, partial lipomatosis and complete lipomatosis of the pancreas. We also assessed the presence or absence of pancreatic calcifications. Forty-one CFRD and 53 CF control participants were included. Only 2% of the patients with CFRD had a normal pancreas, as compared with 30% of the participants from the CF control group (p = 0.0016). Lipomatosis was more frequent in subjects with CFRD and was related to exocrine pancreatic insufficiency (EPI) and to severe CFTR mutations (classes I to III). Nine participants with diabetes (22%) presented with pancreatic calcifications, versus none of the control participants (p = 0.0003). In conclusion, pancreas imaging was almost always abnormal in subjects with CFRD, while it was normal in a third of the CF control subjects. Pancreatic calcifications were specific of subjects with CFRD.

Evolving Nutritional Needs in Cystic Fibrosis

The course of cystic fibrosis (CF) as a nutritional illness is diverging since the introduction of highly effective modulator therapy, leading to more heterogeneous phenotypes of the disease despite CF genetic mutations that portend worse prognosis. This may become more evident as we follow the pediatric CF population into adulthood as some highly effective modulator therapies (HEMT) are approved for those as young as 1 year old. This review will outline the current research and knowledge available in the evolving nutritional health of people with CF as it relates to the impact of HEMT on anthropometrics, body composition, and energy expenditure, exocrine and endocrine pancreatic insufficiencies (the latter resulting in CF-related diabetes), vitamin and mineral deficiencies, and nutritional health in CF as it relates to pregnancy and lung transplantation.

CFTR Modulators: Current Status and Evolving Knowledge

In the past decade, the medical management of people with cystic fibrosis (pwCF) has changed with the development of small molecules that partially restore the function of the defective CF transmembrane conductance regulator (CFTR) protein and are called CFTR modulators. Ivacaftor (IVA), a CFTR potentiator with a large effect on epithelial ion transport, was the first modulator approved in pwCF carrying gating mutations. Because IVA was unable to restore sufficient CFTR function in pwCF with other mutations, two CFTR correctors (lumacaftor and tezacaftor) were developed and used in combination with IVA in pwCF homozygous for F508del, the most common CFTR variant. However, LUM/IVA and TEZ/IVA were only moderately effective in F508del homozygous pwCF and had no efficacy in those with F508del and minimal function mutations. Elexacaftor, a second-generation corrector, was thus developed and combined to tezacaftor and ivacaftor (ELX/TEZ/IVA) to target pwCF with at least one F508del variant, corresponding to approximately 85% of pwCF. Both IVA and ELX/TEZ/IVA are considered highly effective modulator therapies (HEMTs) in eligible pwCF and are now approved for nearly 90% of the CF population over 6 years of age. HEMTs are responsible for rapid improvement in respiratory manifestations, including improvement in symptoms and lung function, and reduction in the rate of pulmonary exacerbations. The impact of HEMT on extrapulmonary manifestations of CF is less well established, although significant weight gain and improvement in quality of life have been demonstrated. Recent clinical trials and real-world studies suggest that benefits of HEMT could even prove greater when used earlier in life (i.e., in younger children and infants). This article shortly reviews the past 10 years of development and use of CFTR modulators. Effects of HEMT on extrapulmonary manifestations and on CF demographics are also discussed.

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.

Can Bioactive Food Substances Contribute to Cystic Fibrosis-Related Cardiovascular Disease Prevention?

Advances in cystic fibrosis (CF) care have significantly improved the quality of life and life expectancy of patients. Nutritional therapy based on a high-calorie, high-fat diet, antibiotics, as well as new therapies focused on CFTR modulators change the natural course of the disease. They do so by improving pulmonary function and growing BMI. However, the increased weight of such patients can lead to unwanted long-term cardiovascular effects. People with CF (pwCF) experience several cardiovascular risk factors. Such factors include a high-fat diet and increased dietary intake, altered lipid metabolism, a decrease in the level of fat-soluble antioxidants, heightened systemic inflammation, therapeutic interventions, and diabetes mellitus. PwCF must pay special attention to food and eating habits in order to maintain a nutritional status that is as close as possible to the proper physiological one. They also have to benefit from appropriate nutritional counseling, which is essential in the evolution and prognosis of the disease. Growing evidence collected in the last years shows that many bioactive food components, such as phytochemicals, polyunsaturated fatty acids, and antioxidants have favorable effects in the management of CF. An important positive effect is cardiovascular prevention. The possibility of preventing/reducing cardiovascular risk in CF patients enhances both quality of life and life expectancy in the long run.

Current and Future Therapeutic Approaches of Exocrine Pancreatic Insufficiency in Children with Cystic Fibrosis in the Era of Personalized Medicine

This review presents current updates of pancreatic enzyme replacement therapy in children with cystic fibrosis based on literature published in the last decade and some special considerations regarding pancreatic enzyme replacement therapy in the era of new therapies, such as cystic fibrosis transmembrane conductance regulator modulator therapies. Few articles evaluate the efficacy of pancreatic enzyme replacement therapy in the pediatric population, and most studies also included children and adults with cystic fibrosis. Approximately 85% of cystic fibrosis patients have exocrine pancreatic insufficiency and need pancreatic enzyme replacement therapy. Fecal elastase is the most commonly used diagnostic test for exocrine pancreatic insufficiency, although this value can fluctuate over time. While it is used as a diagnostic test, it cannot be used for monitoring the effectiveness of pancreatic enzyme replacement therapy and for adjusting doses. Pancreatic enzyme replacement therapy, the actual treatment for exocrine pancreatic insufficiency, is essential in children with cystic fibrosis to prevent malabsorption and malnutrition and needs to be urgently initiated. This therapy presents many considerations for physicians, patients, and their families, including types and timing of administration, dose monitoring, and therapy failures. Based on clinical trials, pancreatic enzyme replacement therapy is considered effective and well-tolerated in children with cystic fibrosis. An important key point in cystic fibrosis treatment is the recent hypothesis that cystic fibrosis transmembrane conductance regulator modulators could improve pancreatic function, further studies being essential. Pancreatic enzyme replacement therapy is addressed a complication of the disease (exocrine pancreatic insufficiency), while modulators target the defective cystic fibrosis transmembrane conductance regulator protein. Exocrine pancreatic insufficiency in cystic fibrosis remains an active area of research in this era of cystic fibrosis transmembrane conductance regulator modulator therapies. This new therapy could represent an example of personalized medicine in cystic fibrosis patients, with each class of modulators being addressed to patients with specific genetic mutations.

Obesity in Cystic fibrosis: prevalence, trends and associated factors data from the US cystic fibrosis foundation patient registry

Strong emphasis has been placed historically on increasing weight and improving nutritional status in cystic fibrosis patients. Due to correlation between nutritional indices (e.g. BMI) and lung function, CF Nutrition Guidelines have recommended BMI percentile goals at the 50th percentile or higher. Trends in increasing BMI across CF programs suggest significantly increasing proportions of overweight and obese status in recent years. We identify that between 2000 and 2019 there has been a relative decrease in underweight status by ∼40%, simultaneously with a > 300% increase in overweight status, and >400% increase in obesity. Patient specific factors associated with higher prevalence of obesity included age ≥46, living in a zip code where the median income was < $20,000, having at least one allele with a class IV or V mutation, a ppFEV1 >90 prescribed ivacaftor, and not prescribed pancreatic enzymes. Program specific factors were not identified.

Update on the management of vitamins and minerals in cystic fibrosis

Advancements in respiratory and nutrition management have significantly improved the survival of patients with cystic fibrosis (CF). With the availability of several nutrition interventions such as oral/enteral nutrition supplements, enteric‐coated pancreatic enzymes, and water‐miscible CF‐specific vitamin supplements, frank vitamin deficiencies—with the exception of vitamin D—are rarely encountered in current clinical practice. Whereas they were previously considered as micronutrients, our current understanding of fat‐soluble vitamins and minerals as antioxidants, immunomodulators, and disease biomarkers has been evolving. The impact of highly effective modulators on the micronutrient status of patients with CF remains elusive. This narrative review focuses on the updates on the management of fat‐soluble vitamins and other micronutrients in CF in the current era and identifies the gaps in our knowledge.

Correlates of Pancreatic Enzyme Replacement Therapy Intake in Adults with Cystic Fibrosis: Results of a Cross-Sectional Study

Most people with cystic fibrosis (pwCF) develop pancreatic insufficiency and are treated with pancreatic enzyme replacement therapy (PERT). We aimed to describe the use of PERT and assess the correlates of PERT dose in adult pwCF. In a cross-sectional study at the Copenhagen CF Centre, the participants reported PERT intake, gastrointestinal (GI) symptoms and the use of concomitant treatments. Demographic and clinical characteristics were extracted from the Danish CF Registry. We used linear regression to assess the correlates of PERT dose per kg bodyweight (U-lipase/kg). We included 120 pwCF with a median age of 32.9 years, 46% women and 72% F508delta homozygote. The PERT dose ranged from 0 to 6160 U-lipase/kg per main meal (mean 1828; SD 1115). The PERT dose was associated with participants' sex (men vs. women: 661; 95% CI: 302; 1020 U-lipase/kg), age (-16; 95% CI: -31; -1 U-lipase/kg per year) and weight (-45; 95% CI: -58; -31 U-lipase/kg per kg). Having less frequent constipation and being lung transplanted were also associated with a higher PERT dose. A third of participants did not take PERT for snacks, and this was associated with the frequency of diarrhoea. These findings indicate that PERT intake may be improved to reduce GI symptoms.

Association of Body Mass Index With Clinical Outcomes in Patients With Cystic Fibrosis: A Systematic Review and Meta-analysis

IMPORTANCE

The prevalence of overweight (body mass index [BMI] = 25-29.9 [calculated as weight in kilograms divided by height in meters squared]) and obesity (BMI ≥30) is increasing among patients with cystic fibrosis (CF). However, it is unclear whether there is a benefit associated with increasing weight compared with the reference range (ie, normal) in CF.

OBJECTIVE

To evaluate the association of altered BMI or body composition and clinical outcomes in patients with CF.

DATA SOURCES

For this systematic review and meta-analysis, the literature search was conducted November 2, 2020, of 3 databases: MEDLINE (via PubMed), Embase, and Cochrane Central Register of Controlled Trials.

STUDY SELECTION

Patients older than 2 years diagnosed with CF with altered body composition or BMI were compared with patients having the measured parameters within the reference ranges. Records were selected by title, abstract, and full text; disagreements were resolved by consensus. Cohort studies and conference abstracts were eligible; articles with no original data and case reports were excluded.

DATA EXTRACTION AND SYNTHESIS

Two authors independently extracted data, which were validated by a third author. Studies containing insufficient poolable numerical data were included in the qualitative analysis. A random-effects model was applied in all analyses.

MAIN OUTCOMES AND MEASURES

Pulmonary function, exocrine pancreatic insufficiency (PI), and CF-related diabetes (CFRD) were investigated as primary outcomes. Odds ratios (ORs) or weighted mean differences (WMDs) with 95% CIs were calculated. The hypothesis was formulated before data collection.

RESULTS

Of 10 524 records identified, 61 met the selection criteria and were included in the qualitative analysis. Of these, 17 studies were included in the quantitative synthesis. Altogether, 9114 patients were included in the systematic review and meta-analysis. Overweight (WMD, -8.36%; 95% CI, -12.74% to -3.97%) and obesity (WMD, -12.06%; 95% CI, -23.91% to -0.22%) were associated with higher forced expiratory volume in the first second of expiration compared with normal weight. The odds for CFRD and PI were more likely in patients of normal weight (OR, 1.49; 95% CI, 1.10 to 2.00) than in those who were overweight (OR, 4.40; 95% CI, 3.00 to 6.45). High heterogeneity was shown in the analysis of pulmonary function (I2 = 46.7%-85.9%).

CONCLUSIONS AND RELEVANCE

The findings of this systematic review and meta-analysis suggest that the currently recommended target BMI in patients with CF should be reconsidered. Studies with long-term follow-up are necessary to assess the possible adverse effects of higher BMI or higher fat mass in patients with CF.

Nutrition in Cystic Fibrosis—Some Notes on the Fat Recommendations

Nutrition is important in cystic fibrosis (CF) because the disease is associated with a higher energy consumption, special nutritional deficiencies, and malabsorption mainly related to pancreatic insufficiency. The clinical course with deterioration of lung function has been shown to relate to nutrition. Despite general recommendation of high energy intake, the clinical deterioration is difficult to restrain suggesting that special needs have not been identified and specified. It is well-known that the CF phenotype is associated with lipid abnormalities, especially in the essential or conditionally essential fatty acids. This review will concentrate on the qualitative aspects of fat metabolism, which has mainly been neglected in dietary fat recommendations focusing on fat quantity. For more than 60 years it has been known and confirmed that the patients have a deficiency of linoleic acid, an n-6 essential fatty acid of importance for membrane structure and function. The ratio between arachidonic acid and docosahexaenoic acid, conditionally essential fatty acids of the n-6 and n-3 series, respectively, is often increased. The recently discovered relations between the CFTR modulators and lipid metabolism raise new interests in this field and together with new technology provide possibilities to specify further specify personalized therapy.

Utilization of the Healthy Eating Index in Cystic Fibrosis

(1) Background: Malnutrition has been a hallmark of cystic fibrosis (CF) for some time, and improved nutritional status is associated with improved outcomes. While individuals with CF historically required higher caloric intake than the general population, new CF therapies and improved health in this population suggest decreased metabolic demand and prevalence of overweight and obesity have increased. This study aimed to (a) examine diet quality in a population of young adults with CF using the Healthy Eating Index, a measure of diet quality in accordance with the U.S. Dietary Guidelines for Americans and (b) evaluate and describe how subcomponents of the HEI might apply to individuals with CF (2) Methods: 3-day dietary recalls from healthy adolescents and young adults with CF were obtained and scored based on the Healthy Eating Index (3) Results: Dietary recalls from 26 (14M/12F) adolescents and young adults with CF (ages 16–23), were obtained. Individuals with CF had significantly lower HEI scores than the general population and lower individual component scores for total vegetables, greens and beans, total fruits, whole fruits, total protein, seafood and plant protein and sodium (p values < 0.01 for all). (4) Conclusion: Dietary quality was poor in these healthy adolescents and young adults with CF. Given the increased prevalence of overweight and obesity in CF, updated dietary guidance is urgently needed for this population. The Healthy Eating Index may be a valuable tool for evaluating dietary quality in CF.

Nutrition management in adults with cystic fibrosis

Cystic fibrosis (CF) is a lethal, monogenic, autosomal recessive disease with manifestations in multiple organ systems, including the lungs and gastrointestinal tract, that impact adequate nutrition. This review discusses important aspects of nutrition in adults with CF with a focus on exocrine pancreatic insufficiency, CF-related diabetes, and gastrointestinal motility, as well as how advanced lung disease, CF transmembrane conductance regulator modulators, and aging impact nutrition in CF.

What Do We Know about the Microbiome in Cystic Fibrosis? Is There a Role for Probiotics and Prebiotics?

Cystic fibrosis (CF) is a life-shortening genetic disorder that affects the cystic fibrosis transmembrane conductance regulator (CFTR) protein. In the gastrointestinal (GI) tract, CFTR dysfunction results in low intestinal pH, thick and inspissated mucus, a lack of endogenous pancreatic enzymes, and reduced motility. These mechanisms, combined with antibiotic therapies, drive GI inflammation and significant alteration of the GI microbiota (dysbiosis). Dysbiosis and inflammation are key factors in systemic inflammation and GI complications including malignancy. The following review examines the potential for probiotic and prebiotic therapies to provide clinical benefits through modulation of the microbiome. Evidence from randomised control trials suggest probiotics are likely to improve GI inflammation and reduce the incidence of CF pulmonary exacerbations. However, the highly variable, low-quality data is a barrier to the implementation of probiotics into routine CF care. Epidemiological studies and clinical trials support the potential of dietary fibre and prebiotic supplements to beneficially modulate the microbiome in gastrointestinal conditions. To date, limited evidence is available on their safety and efficacy in CF. Variable responses to probiotics and prebiotics highlight the need for personalised approaches that consider an individual’s underlying microbiota, diet, and existing medications against the backdrop of the complex nutritional needs in CF.

The Exocrine Pancreas in Cystic Fibrosis in the Era of CFTR Modulation: A Mini Review

Cystic fibrosis (CF) is a common disorder of autosomal recessive inheritance, that once conferred a life expectancy of only a few months. Over recent years, significant advances have been made to CF therapeutic approaches, changing the face of the disease, and facilitating the partial restoration of pancreatic function. This mini review summarizes the current landscape of exocrine pancreatic management in CF and explores areas for future direction and development.

Genetic Modifying Factors of Cystic Fibrosis Phenotype: A Challenge for Modern Medicine

Cystic fibrosis (CF) is a monogenic autosomal recessive disease caused by cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations. CF is characterized by a high phenotypic variability present even in patients with the same genotype. This is due to the intervention of modifier genes that interact with both the CFTR gene and environmental factors. The purpose of this review is to highlight the role of non-CFTR genetic factors (modifier genes) that contribute to phenotypic variability in CF. We analyzed literature data starting with candidate gene studies and continuing with extensive studies, such as genome-wide association studies (GWAS) and whole exome sequencing (WES). The results of both types of studies revealed that the number of modifier genes in CF patients is impressive. Their identification offers a new perspective on the pathophysiological mechanisms of the disease, paving the way for the understanding of other genetic disorders. In conclusion, in the future, genetic analysis, such as GWAS and WES, should be performed routinely. A challenge for future research is to integrate their results in the process of developing new classes of drugs, with a goal to improve the prognosis, increase life expectancy, and enhance quality of life among CF patients.