Growth in prepubertal children with cystic fibrosis, homozygous for the Delta F508 mutation

Trends in Growth and Maturation in Children with Cystic Fibrosis Throughout Nine Decades

Since cystic fibrosis (CF) was first described in 1938, there have been many discoveries and innovations in the field, each having a profound impact on survival, growth and quality of life. For example, the introduction of enteric-coated pancreatic enzyme microspheres increased fat absorption and improved nutritional status. Early detection of CF through newborn screening facilitated prompt nutritional intervention for infants at high risk of malnutrition. Use of anti-pseudomonal therapy, such as inhaled tobramycin, increased weight gain and pulmonary function in addition to reducing pulmonary exacerbations. Similarly, DNAse and hypertonic saline improved pulmonary function and reduced exacerbations. The identification of the CFTR gene and its protein product were fundamental in understanding the pathophysiology of CF and paved the way for advances in both diagnosis and management. In fact, CFTR modulator therapies have revolutionized the care for individuals with CF. Here, we examine the impact of these interventions on the nutritional status, growth and pubertal maturation of children and adolescents with CF.

Academy of Nutrition and Dietetics: 2020 Cystic Fibrosis Evidence Analysis Center Evidence-Based Nutrition Practice Guideline

The Academy of Nutrition and Dietetics Evidence Analysis Center conducted a systematic review of the literature to develop an evidence-based practice guideline for primary nutrition issues in cystic fibrosis (CF). This guideline is designed to complement and build upon existing evidence-based CF nutrition guidelines. The objective of this guideline was to provide recommendations for registered dietitian nutritionists in the United States delivering medical nutrition therapy to individuals with CF and their families that fill gaps in current evidence-based guidelines on topics that are crucial in order to improve health and prevent disease progression. This guideline provides 28 nutrition recommendations to guide medical nutrition therapy, including nutrition screening, nutrition assessment, and dietary intake. For topics outside the scope of this guideline, practitioners are referred to external, evidence-based recommendations. The CF landscape is evolving rapidly with breakthroughs in cystic fibrosis transmembrane regulator modulators changing CF at a cellular level. Medical nutrition therapy for individuals with CF from infancy through advanced age requires novel and individualized approaches. The Academy Evidence Analysis Library CF guidelines provide a framework for expanding upon current knowledge to determine effective nutrition strategies for individuals with CF through long and healthy futures.

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.

Growth and the Growth Hormone-Insulin Like Growth Factor 1 Axis in Children With Chronic Inflammation: Current Evidence, Gaps in Knowledge, and Future Directions

Growth failure is frequently encountered in children with chronic inflammatory conditions like juvenile idiopathic arthritis, inflammatory bowel disease, and cystic fibrosis. Delayed puberty and attenuated pubertal growth spurt are often seen during adolescence. The underlying inflammatory state mediated by proinflammatory cytokines, prolonged use of glucocorticoid, and suboptimal nutrition contribute to growth failure and pubertal abnormalities. These factors can impair growth by their effects on the GH-IGF axis and also directly at the level of the growth plate via alterations in chondrogenesis and local growth factor signaling. Recent studies on the impact of cytokines and glucocorticoid on the growth plate further advanced our understanding of growth failure in chronic disease and provided a biological rationale of growth promotion. Targeting cytokines using biological therapy may lead to improvement of growth in some of these children, but approximately one-third continue to grow slowly. There is increasing evidence that the use of relatively high-dose recombinant human GH may lead to partial catch-up growth in chronic inflammatory conditions, although long-term follow-up data are currently limited. In this review, we comprehensively review the growth abnormalities in children with juvenile idiopathic arthritis, inflammatory bowel disease, and cystic fibrosis, systemic abnormalities of the GH-IGF axis, and growth plate perturbations. We also systematically reviewed all the current published studies of recombinant human GH in these conditions and discussed the role of recombinant human IGF-1.

Nutrional status and dietary factors in cystic fibrosis patients with delta F508 mutation

Objective To examine the association between nutritional status and dietary factors in children and adolescents with cystic fibrosis that are carriers of delta F508 mutation. Methods Cross-sectional study of cystic fibrosis children and adolescents. Nutritional status (body mass index percentile) and dietary intake (3-day diet records presented as a percentage of estimated energy requirement) were assessed. Results Thirty six patients (median of 8.6; interquartile range 6.8-12.5 years; 50% male). The Poisson regression analysis showed that the carriers for delta F508 mutation had 60% lower prevalence ratio of body mass index ≥25° (PR=0.4; 95%IC=0.2-0.8) and 90% lower prevalence ratio (PR=0.1; confidence interval 95%IC=0.02-0.3) of ≥150% of estimated energy requirement when compared with non-delta F508 mutation carriers. The model was adjusted for lung function, estimated energy requirement, and body mass index. Conclusion Carriers for delta F508 mutation showed lower body mass index percentile and lower daily caloric consumption when compared with patients without this mutation.

Growth and long-term lung function in cystic fibrosis: a longitudinal study of patients diagnosed by neonatal screening

OBJECTIVE

So far there is no long-term analysis relating the achievement of growth milestones (such as prepubertal and pubertal take-off and peak velocity) to the course of respiratory function from childhood to adulthood in cystic fibrosis. This study was designed to evaluate linear growth and severity of lung disease, find a correlation between growth and disease severity throughout childhood.

PATIENTS

One hundred sixty-three patients from one center were selected according to: diagnosis by neonatal screening, complete follow-up available (four height measurements/year) until the age of 20, respiratory tests available from the age of 5-6 years until adulthood, lung transplantation, or death. Disease was classified as mild or severe according to FEV(1) (group 1 and group 2). A third group of patients (group 3) consisted of those who died or underwent lung transplantation before the age of 18.

METHODS

Individual growth profiles were fitted with a seven-constant nonlinear growth function. A multivariate linear model was fitted, with gender and severity of disease as covariates, and age, height, and height velocity at growth milestones as dependent variables. Data were compared with those of the normal Italian population.

RESULTS

Lung disease severity correlates with delayed prepubertal and pubertal growth milestones. Peak height velocities were significantly reduced in relation to the severity of the disease.

CONCLUSIONS

Patients with severe forms of cystic fibrosis exhibit reduced growth velocity values at an early age, before a clear decline in pulmonary function.

Late consequences of chronic pediatric illness

There are many challenges in coping with and adapting to life with a chronic disease, and increased survival cannot be assumed to be associated with increased quality of life. A recent systematic review shows there is wide variation in outcomes depending on the definitions and measurements used to estimate the prevalence of chronic health conditions, making the impact of disability on children's health and social functioning difficult to assess; various authors have called for an international consensus about the conceptual definition of chronic health conditions in childhood. It frequently is difficult to determine if problems in psychosocial functioning are caused by the underlying illness, by treatment, or by the resultant effects of either illness or treatment on physical growth or cognitive development. Assessment and treatment of mental health should be an integral component of the comprehensive care of chronically ill children and adolescents. Transition of care is an important process that addresses significant changes from child-oriented to adult-oriented care. Adults who have chronic health conditions should continue to be evaluated periodically for late consequences of the childhood illness and early medical care, and attention should be paid to their ongoing psychosocial, psychiatric, educational, and vocational needs.