The optimal approach to nutrition and cystic fibrosis: latest evidence and recommendations

LLL 44 - Module 3: Micronutrients in Chronic disease

Micronutrients (MN), i.e. trace elements and vitamins, are essential organic molecules, which are required in the diet in relatively small amounts in any form of nutrition (oral, enteral, parenteral). The probability of MN depletion or deficiencies should be considered in all chronic illnesses, especially in those that can interfere with intake, digestion, or intestinal absorption. Low socio-economic status and food deprivation are recognized as the most prevalent reasons for MN deficiencies world-wide. Elderly multimorbid patients with multimodal therapy, as well as patients with long-lasting menu restrictions, are at high risk for both disease related malnutrition as well as multiple MN deficiencies, needing careful specific follow-up. The importance of monitoring MN blood levels along with CRP is essential for optimal care. Drug interactions are also highlighted. In patients with chronic conditions depending on medical nutrition therapy, the provision of adequate dietary reference intakes (DRI) of MN doses and monitoring of their adequacy belongs to standard of care.

The predictive role of lung clearance index on FEV1 decline in cystic fibrosis

BACKGROUND

The lung clearance index (LCI) is a sensitive lung function index that is used to detect early lung disease changes in children with cystic fibrosis (CF). This study aimed to define the predictive role of baseline LCI, along with other potential factors on the change in forced expiratory volume in one second (FEV1) during one-year follow-up in CF patients who had a percent predicted (pp) FEV1≥80.

METHODS

LCI was concurrently performed on 57 CF patients who had ppFEV1 ≥80 at month zero. The ppFEV1 decline was evaluated prospectively during the one year follow up. The primary outcome of ppFEV1 decline in the study group in one year was dichotomized according to the median value for the decline in ppFEV1, which was 3.7. The LCI value predicting ppFEV1 decline at the end of one year was calculated with receiver operating characteristic curve analysis. Regression analysis was performed. Furthermore, a decision tree was constructed using classification and regression tree methods to better define the potential effect of confounders on the ppFEV1 decline.

RESULTS

The LCI value for predicting ppFEV1 decline >3.7% at the end of one year was 8.2 (area under the curve: 0.80) Multivariable regression analysis showed that the absence of the F508del mutation in at least one allele, LCI >8.2 and initial FEV1 z-score were predictors of a ppFEV1 decline >3.7 (p<0.001). Factors altering ppFEV1 decline>3.7% at the end of one-year evaluated by decision trees were as follows: initial FEV1 z-score, type of CFTR mutation, LCI value and initial weight-for-age z-score.

CONCLUSIONS

LCI is sensitive for predicting ppFEV1 decline in patients with ppFEV1 ≥80 along with the initial FEV1-z-score and type of CFTR mutation.

Giving adolescents with cystic fibrosis a voice: Predicting cystic fibrosis nutritional adherence from their decision-making involvement

OBJECTIVE

Suboptimal nutritional adherence in adolescents with cystic fibrosis (awCF) has been associated with lower lung function. AwCF often have more independence in dietary decisions than younger children, yet little research has examined how adolescent decision-making relates to nutritional adherence. This study explored whether components of adolescent decision-making involvement facilitate enzyme and caloric adherence in awCF.

METHODS

37 families participated and completed study procedures. AwCF and caregivers completed electronic surveys, including the Decision-Making Involvement Scale (DMIS). The DMIS evaluated awCF behaviors during nutrition-related decision-making/discussions with caregivers using DMIS subscales: Child Seek (asking for help/advice from caregivers), Child Express (awCF stating opinions) and Joint/Options (awCF participating in joint decision-making or caregiver providing options). AwCF completed 2, 24-hr diet recalls via videoconferencing/phone to estimate adherence. Chart reviews collected medical information. DMIS subscales were regressed onto enzyme and caloric adherence.

RESULTS

43% of awCF met calorie recommendations; 48.6% took all enzymes as prescribed. Caloric adherence was positively correlated with adolescent- and parent-reported Child Seek (r = 0.53; r = 0.36) and adolescent-reported Joint/Options (r = 0.41). Per adolescent-report, the caloric adherence regression model was significant, with Child Seek contributing unique variance in caloric adherence (β = .62, p = .03). Parent-reported adolescent-decision-making involvement significantly predicted caloric adherence, but none of the subscales contributed unique variance. No other regressions were significant.

CONCLUSIONS

When awCF participated in nutrition-related discussions with a caregiver, especially with questions, caloric adherence was better. Future research should examine whether family factors influence these results. AwCF are encouraged to ask questions in nutrition discussions.

Standards for the care of people with cystic fibrosis (CF); recognising and addressing CF health issues

This is the third 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 recognising and addressing CF health issues. The guidance was produced with wide stakeholder engagement, including people from the CF community, using an evidence-based framework. Authors contributed sections, and summary statements which were reviewed by a Delphi consultation. Monitoring and treating airway infection, inflammation and pulmonary exacerbations remains important, despite the widespread availability of CFTR modulators and their accompanying health improvements. Extrapulmonary CF-specific health issues persist, such as diabetes, liver disease, bone disease, stones and other renal issues, and intestinal obstruction. These health issues require multidisciplinary care with input from the relevant specialists. Cancer is more common in people with CF compared to the general population, and requires regular screening. The CF life journey requires mental and emotional adaptation to psychosocial and physical challenges, with support from the CF team and the CF psychologist. This is particularly important when life gets challenging, with disease progression requiring increased treatments, breathing support and potentially transplantation. Planning for end of life remains a necessary aspect of care and should be discussed openly, honestly, with sensitivity and compassion for the person with CF and their family. CF teams should proactively recognise and address CF-specific health issues, and support mental and emotional wellbeing while accompanying people with CF and their families on their life journey.

Exocrine Pancreatic Insufficiency in Children - Challenges in Management

Cystic fibrosis (CF) is the leading etiology for exocrine pancreatic insufficiency (EPI) in children, followed by chronic pancreatitis, Shwachman-Diamond syndrome, and other genetic disorders. Management of EPI in children poses several unique challenges such as difficulties in early recognition, lack of widespread availability of diagnostic tests and limited number of pediatric-specific pancreatic centers. Pancreatic enzyme replacement therapy is the cornerstone of EPI management and in young children difficulties in administering pancreatic enzymes are frequently encountered. Patients with EPI also should be screened for fat-soluble vitamin deficiencies and receive appropriate supplementation. Among disorders with EPI in children, CF is the relatively well-studied condition, and most management recommendations for EPI in children come from expert consensus and conventional practice guidelines. The impact of EPI can be greater in children given their high metabolic demands and rapid growth. Early diagnosis and aggressive management of EPI prevent consequences of complications such as malnutrition, fat-soluble vitamin deficiencies, and poor bone health and improve outcomes. Management by multi-disciplinary team is the key to success.

Effect of oral nutritional supplements on outcomes in children presenting with, or at risk of, faltering growth in clinical settings: A systematic review and meta-analysis

This systematic review summarises evidence regarding oral nutritional supplement (ONS) use in children with, or at risk of, faltering growth (FG). Ten randomised controlled trials (RCTs), compared changes in outcomes amongst children receiving ONS versus control were included. Overall, 1116 children (weighted mean (WM) age 5 years; n658 (59%) male) were recruited, of which 585 (52%) received ONS (WM intake contribution 412 kcal, 16.3 g protein, 395 ml) for 116 days (WM). ONS use was associated with significantly greater gains in weight (mean difference (MD) 0.4 kg, 95% CI [0.36, 0.44]) and height (MD 0.3 cm, 95% CI [0.03, 0.57]), likely related to improvements in nutritional intake. Mean compliance to prescribed dose was 98%. Data suggested an association between ONS use and reduced infections. Further research is warranted to establish ONS dosage and effects upon other outcomes. This review provides evidence to support use of ONS in the management of children with, or at risk of, FG.

Intestinal Absorption of Lipids Using a Pancreatic Enzyme-Free Nutritional Supplement in Patients with Cystic Fibrosis: A Randomized, Double-Blind, Crossover Pilot Trial

Nutritional supplements for patients with exocrine pancreatic insufficiency (EPI) typically utilize pancreatic enzyme replacement therapy (PERT) which is associated with gastrointestinal side effects. We evaluated serum triglyceride levels in patients with cystic fibrosis following consumption of an enzyme-modified oil oral nutritional supplement (EMO-ONS) versus a standard triacylglycerol-based ONS product (TAG-ONS) used concomitantly with PERT and patient tolerability between the two approaches. Ten subjects with CF and EPI taking PERT were enrolled in a single-center, double-blind, cross-over proof of concept trial. Five subjects randomized to Arm 1 were administered a PERT placebo and EMO-ONS and 5 subjects in Arm 2 were administered TAG-ONS+PERT. After 4 to 14 days, subjects received the opposite ONS. Serum triglyceride levels were measured at baseline and hourly for 6 h. Following the above, subjects were randomly assigned to receive 2 daily servings of EMO-ONS+PERT placebo or TAG-ONS+PERT at home for 7-days, self-reporting gastrointestinal symptoms daily. Mean change in peak serum triglyceride levels were similar for both groups (EMO-ONS = 41.9 ± 46.7 mg/dL vs. TAG-ONS+PERT = 46.4 ± 44.1 mg/L; p = 0.85). There was no difference in mean ratio of the serum triglyceride AUC between the two groups (p = 0.58) or self-reported gastrointestinal tolerance. EMO-based products may provide a PERT-free alternative to traditional ONS products in patients with cystic fibrosis.

Cystic fibrosis newborn screening: Five-year experience from a tertiary care center

BACKGROUND

Newborn screening (NBS) for cystic fibrosis (CF) was implemented in our country on January 1, 2015, based on immunoreactive trypsinogen tests (IRT/IRT). Here, we aimed to evaluate the diagnoses of patients and follow-up process within the first 5 years of NBS from a tertiary care center.

METHODS

This retrospective cohort study was conducted on patients who were admitted to our pediatric pulmonology department for sweat test (ST) via NBS. Patients with CF with negative NBS results and those with CF with positive NBS and joined our follow-up were also investigated. Clinical outcome measures were compared between patients with CF with positive and negative NBS.

RESULTS

Six hundred sixty infants who were referred for ST via NBS were included. Across the entire study population (n = 683), 11.4% of patients had CF (14.1% of had negative NBS in this CF group). The sensitivity of NBS was found as 84.9% and the positive predictive value (PPV) was 9.4%. The median age at diagnosis was older (p < 0.001), reluctance for feeding and Pseudobartter syndrome (PBS) were significantly higher at presentation in the negative NBS group. There was no statistically significant difference between the groups regarding weight-for-age (p = 0.899) and height-for-age (p = 0.491) in the first 2 years' follow-ups.

CONCLUSIONS

Our findings showed the low sensitivity and PPV of NBS; therefore, further studies based on all patients in our country are necessary for new cut-off values. PBS and reluctance for feeding should be alarm symptoms for CF even if the infants had negative NBS. Additionally, later diagnosis of patients who had negative NBS did not affect the nutritional outcomes; we need large-scale prospective studies to optimize nutritional benefits for all infants diagnosed via NBS.

Standards of Nutritional Care for Patients with Cystic Fibrosis: A Methodological Primer and AGREE II Analysis of Guidelines

Although many Clinical Practice Guidelines (CPGs) have been published for the care of patients with Cystic Fibrosis (CF), including a variety of nutrition recommendations, the quality of these CPGs has never been evaluated. The aim of this study was to compare, review, and critically appraise CPGs for the nutritional management of CF, throughout the lifespan. We searched PubMed, Guidelines International Network (GIN), ECRI Institute, and Guidelines Central for CPGs, with information on the nutritional management of CF. Retrieved CPGs were appraised by three independent reviewers, using the Appraisal of Guidelines, Research and Evaluation II (AGREE II) instrument and checklist. A total of 22 CPGs (seven solely nutrition oriented), by 14 different publishers, were retrieved. The Thoracic Society of Australia and New Zealand CPGs scored the highest overall quality (94.4%), while the Paediatric Gastroenterology Society/Dietitians Association of Australia CPGs had the lowest score (27.8%). Great variation in AGREE II domain-specific scores was observed in all CPGs, suggesting the existence of different strengths and weaknesses. Despite the availability of several CPGs, many appear outdated, lacking rigor, transparency, applicability, and efficiency, while incorporating bias. Considering that CPGs adherence is associated with better outcomes and the need for improving life expectancy in patients with CF, the development of CPGs of better quality is deemed necessary.

Activated L-Arginine/Nitric Oxide Pathway in Pediatric Cystic Fibrosis and Its Association with Pancreatic Insufficiency, Liver Involvement and Nourishment: An Overview and New Results

Cystic fibrosis (CF; OMIM 219700) is a rare genetic disorder caused by a chloride channel defect, resulting in lung disease, pancreas insufficiency and liver impairment. Altered L-arginine (Arg)/nitric oxide (NO) metabolism has been observed in CF patients’ lungs and in connection with malnutrition. The aim of the present study was to investigate markers of the Arg/NO pathway in the plasma and urine of CF patients and to identify possible risk factors, especially associated with malnutrition. We measured the major NO metabolites nitrite and nitrate, Arg, a semi-essential amino acid and NO precursor, the NO synthesis inhibitor asymmetric dimethylarginine (ADMA) and its major urinary metabolite dimethylamine (DMA) in plasma and urine samples of 70 pediatric CF patients and 78 age-matched healthy controls. Biomarkers were determined by gas chromatography–mass spectrometry and high-performance liquid chromatography. We observed higher plasma Arg (90.3 vs. 75.6 µM, p < 0.0001), ADMA (0.62 vs. 0.57 µM, p = 0.03), Arg/ADMA ratio (148 vs. 135, p = 0.01), nitrite (2.07 vs. 1.95 µM, p = 0.03) and nitrate (43.3 vs. 33.1 µM, p < 0.001) concentrations, as well as higher urinary DMA (57.9 vs. 40.7 µM/mM creatinine, p < 0.001) and nitrate (159 vs. 115 µM/mM creatinine, p = 0.001) excretion rates in the CF patients compared to healthy controls. CF patients with pancreatic sufficiency showed plasma concentrations of the biomarkers comparable to those of healthy controls. Malnourished CF patients had lower Arg/ADMA ratios (p = 0.02), indicating a higher NO synthesis capacity in sufficiently nourished CF patients. We conclude that NO production, protein-arginine dimethylation, and ADMA metabolism is increased in pediatric CF patients. Pancreas and liver function influence Arg/NO metabolism. Good nutritional status is associated with higher NO synthesis capacity and lower protein-arginine dimethylation.

Mucoviscidosis: fisiopatología, genética, aspectos clínicos y terapéuticos

La mucoviscidosis es la enfermedad autosómica recesiva grave más frecuente que afecta a la población caucásica. En Francia, por ejemplo, la incidencia es de un caso por cada 4.500 nacimientos. Esta enfermedad se debe a mutaciones en el gen CFTR (cystic fibrosis transmembrane conductance regulator, regulador de conductancia transmembrana de la fibrosis quística), situado en el brazo largo del cromosoma 7, que codifica una proteína transmembrana implicada en la regulación del transporte transepitelial de iones cloruro (Cl–). En Francia, la mutación más frecuente (alrededor del 80% de los casos) es la deleción del aminoácido 508 (fenilalanina), denominada F508del. La ausencia o la disfunción de la proteína CFTR provoca un defecto en el transporte de Cl– y un aumento de la reabsorción de sal y agua, en particular en el epitelio bronquial, lo que conlleva una reducción del líquido de la superficie bronquial. Esta exocrinopatía generalizada conduce a la producción de «moco viscoso» (de ahí el nombre de mucoviscidosis), que obstruye varios sitios en el cuerpo, en particular el sistema respiratorio, el tracto digestivo y sus anexos (páncreas, vías biliares e hígado). La detección neonatal se ha generalizado desde 2002. La prueba del sudor es la prueba complementaria de referencia, validada por la identificación de dos mutaciones patógenas, para la confirmación del diagnóstico. El tratamiento es multidisciplinario. Se basa ante todo en la kinesiterapia respiratoria diaria y el tratamiento de las sobreinfecciones broncopulmonares, así como en las recomendaciones nutricionales con el uso de extractos pancreáticos. Es probable que el pronóstico, todavía muy desfavorable, se modifique con la llegada de terapias proteínicas o de edición de ácido ribonucleico o de gen.

Somatic growth in cystic fibrosis

PURPOSE OF REVIEW

Cystic fibrosis (CF) is commonly associated with compromised growth especially in severe cases when the pulmonary function (PFT) deteriorates. As growth optimization is an important aspect of CF management, this review will summarize the current knowledge on the prevalence of growth failure in CF patients, and focus on the mechanisms leading to poor growth, on the association of poor linear growth with reduced PFT and on recombinant human growth hormone (rhGH) therapy in CF patients.

RECENT FINDINGS

Despite the improvement in CF care in the last 2 decades, compromised linear growth is still quite prevalent. The pathophysiology of growth failure in CF is multifactorial. Malnutrition due to decreased energy intake increased energy expenditure and malabsorption of ingested nutrients secondary to pancreatic insufficiency, all probably play a major role in growth restriction. In addition, chronic inflammation characteristic of CF may contribute to growth failure via alteration in the GH-insulin-like growth factor 1 signaling and other changes in the growth plate. rhGH and new CFTR modulators may improve some growth parameters.

SUMMARY

Beyond optimizing nutrition and malabsorption, and controlling chronic inflammation, children with CF may benefit from the anabolic effects of rhGH therapy to improve their anthropometric parameters. Whether this translates into better PFT and improved long-term outcomes is yet to be determined.

Neonatal cholestasis: recent insights

Background

Neonatal physiological jaundice is a common benign condition that rarely extends behind the second week of life; however, it may interfere with the diagnosis of a pathological condition termed neonatal cholestasis (NC). The latter is a critical, uncommon problem characterized by conjugated hyperbilirubinaemia. This review aims to highlight the differences between physiological and pathological jaundice, identify different causes of NC, and provide a recent approach to diagnosis and management of this serious condition.

Main text

NC affects 1/2500 live births, resulting in life-threatening complications due to associated hepatobiliary or metabolic abnormalities. NC is rarely benign and indicates the presence of severe underlying disease. If jaundice extends more than 14 days in full-term infants or 21 days in preterm infants, the serum bilirubin level fractionated into conjugated (direct) and unconjugated (indirect) bilirubin should be measured. A stepwise diagnostic approach starts with obtaining a complete history, and a physical examination which are valuable for the rapid diagnosis of the underlying disease. The most frequently diagnosed causes of NC are biliary atresia (BA) and idiopathic neonatal hepatitis (INH). The early diagnosis of NC ensures more accurate management and better prognosis. Despite the unavailability of any specific treatments for some causes of NC, the patient can benefit from nutritional management and early medical intervention. Future research should attempt to shed light on methods of screening for NC, especially for causes that can be effectively treated either through proper nutritional support, appropriate chemotherapeutic management, or timely surgical intervention.

Conclusion

Further attention should be paid for diagnosis and treatment of NC as it may be misdiagnosed as physiological jaundice; this may delay the proper management of the underlying diseases and aggravates its complications.

Evaluating the impact of 2006 Australasian Clinical Practice Guidelines for nutrition in children with cystic fibrosis in Australia

OBJECTIVES

To determine the association between the implementation of the 2006 Australasian Clinical Practice Guidelines for Nutrition in Cystic Fibrosis (CF) and the nutritional status of children participating in the Australian Cystic Fibrosis Data Registry (ACFDR).

METHODS

This research consisted of a quantitative study using ACFDR data and a survey of clinicians and dietitians treating children with CF. Two independent cohorts of children (2-5 years and 6-11 years) were selected from ACFDR between 1998 and 2014 (N = 2304). Generalised estimating equation model was used to assess weight, height and body mass index (BMI) z-scores for each patient before and after the implementation of the nutrition guidelines. A nationwide online survey was sent to 48 clinicians to explore the enablers and barriers to implementation of the guidelines.

RESULTS

Data analysis showed significant increase (p < 0.05) in mean weight, height and BMI z-scores ranging from 0.06 to 0.18 after implementation of the guidelines in both cohorts of children. Nineteen (39%) clinicians participated in the survey. The majority of the respondents adopted the recommendations into their practice and used the guidelines as part of their professional development. Structural barriers included a lack of adequate staff resources and clinic space for consultations, inappropriate staff classification, high staff turnover and lack of mentoring support.

CONCLUSION

In children participating in the ACFDR, nutritional status improved after the implementation of the 2006 guidelines. Survey results revealed enablers and barriers to guideline implementation and will inform implementation strategies for the revised Australasian nutrition guidelines for CF, released in 2017.