Growth hormone treatment enhances nutrition and growth in children with cystic fibrosis receiving enteral nutrition

Appetite stimulants for people with cystic fibrosis

BACKGROUND

Chronic loss of appetite in cystic fibrosis concerns both individuals and families. Appetite stimulants have been used to help cystic fibrosis patients with chronic anorexia attain optimal body mass index (BMI) and nutritional status. However, these may have adverse effects on clinical status. This is an updated version of the original review.

OBJECTIVES

To systematically search for and evaluate the evidence on the beneficial effects of appetite stimulants in the management of cystic fibrosis-related anorexia and synthesise reports of any side effects.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register and online trials registries; handsearched reference lists; and contacted local and international experts to identify relevant trials. Last search of the Cystic Fibrosis Trials Register: 23 May 2022. Last search of online trial registries: 10 May 2022.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of appetite stimulants compared to placebo, control, no treatment or different appetite stimulants, or to the same appetite stimulants at different doses or regimens for at least one month in adults and children with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Review authors independently extracted data and assessed risk of bias of the included trials. We used the GRADE approach to assess the certainty of the evidence and performed meta-analyses.

MAIN RESULTS

We included four trials (70 participants) comparing appetite stimulants (cyproheptadine hydrochloride and megestrol acetate) to placebo; the numbers of adults or children within each trial were not always reported. We assessed the certainty of evidence as low due to the small number of participants, incomplete or selective outcome reporting, and unclear risk of selection bias.  Regarding our primary outcomes, a meta-analysis of two trials (42 participants) showed that appetite stimulants may produce a larger increase in weight (kg) at three months (mean difference (MD) 1.25 kg, 95% confidence interval (Cl) 0.45 to 2.05), and one trial (17 participants) showed a similar result at six months (MD 3.80 kg, 95% CI 1.27 to 6.33) (both low-certainty evidence). Results also showed that weight z score may increase with appetite stimulants compared to placebo at three months (MD 0.61, 95% CI 0.29 to 0.93; 3 studies; 40 participants; P < 0.001) and at six months (MD 0.74, 95% CI 0.26 to 1.22; 1 trial; 17 participants). There was no evidence of a difference in effect between cyproheptadine hydrochloride and megestrol acetate for either outcome.   Only one trial (25 participants) reported analysable data for body composition (BMI), with results favouring cyproheptadine hydrochloride compared to placebo; a further trial (16 participants) narratively agreed with this result. All four trials reported on lung function at durations ranging from two to nine months. Considering analysable data, two trials (42 participants) found that appetite stimulants may make little or no difference in forced expiratory volume at one second (FEV1) % predicted at three months, and one trial (17 participants) found similar results at six months. Two further three-month trials narratively agreed with these results. Limited information was reported for secondary outcomes. Two trials (23 participants) reported results showing that appetite stimulants may increase appetite compared to placebo at three months (odds ratio 45.25, 95% CI 3.57 to 573.33; low-certainty evidence).  Only one study reported on quality of life, finding that cyproheptadine reduced fatigue in two participants compared with none with placebo. One study (25 participants) found no difference in energy intake between appetite stimulant or placebo at three months. Insufficient reporting of adverse effects prevented a full determination of their impact. Two studies (33 participants) narratively reported similar requirements for additional antibiotics between appetite stimulants and placebo at three months.  AUTHORS' CONCLUSIONS: At six months in adults and children, appetite stimulants improved only two of the outcomes of this review: weight (or weight z score) and subjectively reported appetite. Insufficient reporting of side effects prevented a full determination of their impact. Whilst the data may suggest the potential use of appetite stimulants in treating anorexia in adults and children with cystic fibrosis, this is based upon low-certainty evidence from a small number of trials, therefore firm conclusions cannot be drawn. Clinicians need to be aware of the potential adverse effects of appetite stimulants and actively monitor any individuals prescribed these medications accordingly. Research is required to determine meaningful surrogate measures for appetite and to define what constitutes quality weight gain. Future trials of appetite stimulants should use a validated measure of symptoms including a disease-specific instrument for measuring poor appetite. This review highlights the need for multicentred, adequately powered, and well-designed trials to evaluate agents to safely increase appetite in people with cystic fibrosis and to establish the optimal mode of treatment.

Evaluation of growth hormone deficiency in children with cystic fibrosis

Background:

Due to chronic respiratory and gastrointestinal problems, growth failure is a common issue in patients with cystic fibrosis (CF). The present study aimed to investigate the prevalence of growth hormone deficiency (GHD) in CF children with stable gastrointestinal and respiratory conditions.

Materials and Methods:

In this study, the growth indicators of all 4–16-year-old children referred to two CF clinics were monitored over 3 years. Children without severe gastrointestinal or pulmonary symptoms with weight <3% percentile or whose height increase were two standard deviations below their expected height growth over 6 months were selected for the growth hormone (GH) stimulation test by clonidine and L-dopa test. Some of the children without CF, who were also referred for height growth disorders and matched the CF group, were considered the control group. They underwent the GH stimulation test, and the results were compared.

Results:

From 150 patients with CF, growth failure was observed in 24 patients with stable gastrointestinal and respiratory conditions; in 10 of them, the GH stimulation test was deficient. The prevalence of GHD was 6.6% in CF patients. In the control group of 30 children without CF, but with growth failure, the GH was deficient in nine cases, implying no significant difference with the case group (P = 0.37).

Conclusion:

In our study, the prevalence of GHD was 6.6% in CF patients, whereas the prevalence GHD in the normal population of childhood is <1%. Therefore, further studies should be designed to investigate the cause of GHD in CF patients.

Most Short Children with Cystic Fibrosis Do Not Catch Up by Adulthood

Poor linear growth is common in children with cystic fibrosis (CF) and predicts pulmonary status and mortality. Growth impairment develops in infancy, prior to pulmonary decline and despite aggressive nutritional measures. We hypothesized that growth restriction during early childhood in CF is associated with reduced adult height. We used the Cystic Fibrosis Foundation (CFF) patient registry to identify CF adults between 2011 and 2015 (ages 18–19 y, n = 3655) and had height for age (HFA) records between ages 2 and 4 y. We found that only 26% CF adults were ≥median HFA and 25% were <10th percentile. Between 2 and 4 years, those with height < 10th percentile had increased odds of being <10th percentile in adulthood compared to children ≥ 10th percentile (OR = 7.7). Of HFA measured between the 10th and 25th percentiles at ages 2–4, 58% were <25th percentile as adults. Only 13% between the 10th and 25th percentile HFA at age 2–4 years were >50th percentile as adults. Maximum height between ages 2 and 4 highly correlated with adult height. These results demonstrate that low early childhood CF height correlates with height in adulthood. Since linear growth correlates with lung growth, identifying both risk factors and interventions for growth failure (nutritional support, confounders of clinical care, and potential endocrine involvement) could lead to improved overall health.

Recombinant growth hormone therapy for cystic fibrosis in children and young adults

BACKGROUND

Cystic fibrosis (CF) is an inherited condition causing disease most noticeably in the lungs, digestive tract and pancreas. People with CF often have malnutrition and growth delay. Adequate nutritional supplementation does not improve growth optimally and hence an anabolic agent, recombinant human growth hormone (rhGH), has been proposed as a potential intervention. This is an update of a previously published review.

OBJECTIVES

To evaluate the effectiveness and safety of rhGH therapy in improving lung function, quality of life and clinical status of children and young adults with CF.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Date of latest search: 12 January 2021. We also searched ongoing trials registers: clinicaltrials.gov from the United States - date of latest search 19 Jun 2021; WHO International Clinical Trials Registry Platform (ICTRP) - date of latest search 05 March 2018 (not available in 2021).  We conducted a search of relevant endocrine journals and proceedings of the Endocrinology Society meetings using Web of Science, Scopus and Proceedings First. Date of latest search: 21 Jun 2021.  SELECTION CRITERIA: Randomised and quasi-randomised controlled trials of all preparations of rhGH compared to either no treatment, or placebo, or each other at any dose (high-dose and low-dose) or route and for any duration, in children or young adults (aged up to 25 years) diagnosed with CF (by sweat test or genetic testing).

DATA COLLECTION AND ANALYSIS

Two authors independently screened papers, extracted trial details and assessed their risk of bias. We assessed the quality of the evidence using the GRADE system.

MAIN RESULTS

We included eight trials (291 participants, aged between five and 23 years) in the current version of the review. Seven trials compared standard-dose rhGH (approximately 0.3 mg/kg/week) to no treatment and one three-arm trial (63 participants) compared placebo, standard-dose rhGH (0.3 mg/kg/week) and high-dose rhGH (0.5 mg/kg/week). Six trials lasted for one year and two trials for six months. We found that rhGH treatment may improve some of the pulmonary function outcomes, but there was no difference between standard and high-dose levels (low-certainty evidence, limited by inconsistency across the trials, small number of participants and short duration of therapy). The trials show evidence of improvement in the anthropometric parameters (height, weight and lean body mass) with rhGH therapy, again no differences between dose levels. We found improvement in height for all comparisons (very low- to low-certainty evidence), but improvements in weight and lean body mass were only reported for standard-dose rhGH versus no treatment (very low-certainty evidence). There is some evidence indicating a change in the level of fasting blood glucose with rhGH therapy, however, it did not cross the clinical threshold for diagnosis of diabetes in the trials of short duration (low-certainty evidence). There is low- to very low-certainty evidence for improvement of pulmonary exacerbations with no further significant adverse effects, but this is limited by the short duration of trials and the small number of participants. One small trial provided inconsistent evidence on improvement in quality of life (very low-certainty evidence). There is limited evidence from three trials in improvements in exercise capacity (low-certainty evidence). None of the trials have systematically compared the expense of therapy on overall healthcare costs.

AUTHORS' CONCLUSIONS

When compared with no treatment, rhGH therapy is effective in improving the intermediate outcomes in height, weight and lean body mass. Some measures of pulmonary function showed moderate improvement, but no consistent benefit was seen across all trials. The significant change in blood glucose levels, although not causing diabetes, emphasizes the need for careful monitoring of this adverse effect with therapy in a population predisposed to CF-related diabetes. No significant changes in quality of life, clinical status or side-effects were observed in this review due to the small number of participants. Long-term, well-designed randomised controlled trials of rhGH in individuals with CF are required prior to routine clinical use of rhGH in CF.

SFPQ rescues F508del-CFTR expression and function in cystic fibrosis bronchial epithelial cells

Cystic fibrosis (CF) occurs as a result of mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which lead to misfolding, trafficking defects, and impaired function of the CFTR protein. Splicing factor proline/glutamine-rich (SFPQ) is a multifunctional nuclear RNA-binding protein (RBP) implicated in the regulation of gene expression pathways and intracellular trafficking. Here, we investigated the role of SFPQ in the regulation of the expression and function of F508del-CFTR in CF lung epithelial cells. We find that the expression of SFPQ is reduced in F508del-CFTR CF epithelial cells compared to WT-CFTR control cells. Interestingly, the overexpression of SFPQ in CF cells increases the expression as well as rescues the function of F508del-CFTR. Further, comprehensive transcriptome analyses indicate that SFPQ plays a key role in activating the mutant F508del-CFTR by modulating several cellular signaling pathways. This is the first report on the role of SFPQ in the regulation of expression and function of F508del-CFTR in CF lung disease. Our findings provide new insights into SFPQ-mediated molecular mechanisms and point to possible novel epigenetic therapeutic targets for CF and related pulmonary diseases.

Growth failure and treatment in cystic fibrosis

Poor growth has long been a characteristic feature of cystic fibrosis (CF) and is significantly linked to lung function and overall health status. Improvements in pulmonary and nutrition care for patients with cystic fibrosis (CF) have resulted in better growth outcomes; however, height gains have not paralleled the improvements in weight in children with CF, and patients with more severe CF mutations remain significantly more affected. Many factors affect the growth hormone-IGF-1 axis and the growth plate of the long bones, including the chronic inflammatory state associated with CF. There are also increasing data on the direct effects of CFTR on bone and implications for CFTR modulators in attaining optimal growth. Treatments aimed at improving growth in CF are also reviewed here.

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.

Recombinant growth hormone therapy for cystic fibrosis in children and young adults

BACKGROUND

Cystic fibrosis (CF) is an inherited condition causing disease most noticeably in the lungs, digestive tract and pancreas. People with CF often have malnutrition and growth delay. Adequate nutritional supplementation does not improve growth optimally and hence an anabolic agent, recombinant human growth hormone (rhGH), has been proposed as a potential intervention. This is an update of a previously published review.

OBJECTIVES

To evaluate the effectiveness and safety of rhGH therapy in improving lung function, quality of life and clinical status of children and young adults with CF.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Date of latest search: 22 October 2018.We also searched ongoing trials registers in clinicaltrials.gov from the United States and WHO International Clinical Trials Registry Platform (ICTRP). Date of latest search: 05 March 2018.We conducted a search of relevant endocrine journals and proceedings of the Endocrinology Society meetings using Web of Science, Scopus and Proceedings First. Date of latest search: 04 March 2018.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of all preparations of rhGH compared to either no treatment, or placebo, or each other at any dose (high-dose and low-dose) or route and for any duration, in children or young adults (aged up to 25 years) diagnosed with CF (by sweat test or genetic testing).

DATA COLLECTION AND ANALYSIS

Two authors independently screened papers, extracted trial details and assessed their risk of bias. We assessed the quality of the evidence using the GRADE system.

MAIN RESULTS

We included eight trials (291 participants, aged between five and 23 years) in this revision of the review. Seven trials compared standard-dose rhGH (approximately 0.3 mg/kg/week) to no treatment and one three-arm trial (63 participants) compared placebo, standard-dose rhGH (0.3 mg/kg/week) and high-dose rhGH (0.5 mg/kg/week). Six trials lasted for one year and two trials for six months. We found that rhGH treatment may improve some of the pulmonary function outcomes but there was no difference between standard and high-dose levels (low-quality evidence, limited by inconsistency across the trials, small number of participants and short duration of therapy). The trials show evidence of improvement in the anthropometric parameters (height, weight and lean body mass) with rhGH therapy, again no differences between dose levels. We found improvement in height for all comparisons (very low- to low quality evidence), but improvements in weight and lean body mass were only reported for standard-dose rhGH versus no treatment (very low-quality evidence). There is some evidence indicating a change in the level of fasting blood glucose with rhGH therapy, however, it did not cross the clinical threshold for diagnosis of diabetes in the trials of short duration (low-quality evidence). There is low- to very low-quality evidence for improvement of pulmonary exacerbations with no further significant adverse effects, but this is limited by the short duration of trials and the small number of participants. One small trial provided inconsistent evidence on improvement in quality of life (very low-quality evidence). There is limited evidence from three trials in improvements in exercise capacity (low-quality evidence). None of the trials have systematically compared the expense of therapy on overall healthcare costs.

AUTHORS' CONCLUSIONS

When compared with no treatment, rhGH therapy is effective in improving the intermediate outcomes in height, weight and lean body mass. Some measures of pulmonary function showed moderate improvement, but no consistent benefit was seen across all trials. The significant change in blood glucose levels, although not causing diabetes, emphasizes the need for careful monitoring of this adverse effect with therapy in a population predisposed to CF-related diabetes. No significant changes in quality of life, clinical status or side-effects were observed in this review due to the small number of participants. Long-term, well-designed randomised controlled trials of rhGH in individuals with CF are required prior to routine clinical use of rhGH in CF.

Sleep: An underemphasized aspect of health and development in neurorehabilitation

Sleep deficiency has unique causes and implications for children with neonatal brain injury; contributing to the development or exacerbation of neurodevelopmental impairments and yet it is an underemphasized aspect of health and development. There is very little research evidence to guide the management of sleep disorders in children with cerebral palsy, a common neurodevelopmental disability of childhood. This paper is a comprehensive review and analysis of the literature regarding what is known about sleep quantity and quality in children with cerebral palsy. The specific implications for children with cerebral palsy are explored including the adverse effects of sleep deficiency on general child development, physical health and growth, and mental functioning. The consequences for the family are also discussed. Finally, the assessment and management of sleep problems are summarized to provide guidance to clinicians who work in neurodevelopmental medicine.

Quality of Reporting Nutritional Randomized Controlled Trials in Patients With Cystic Fibrosis

OBJECTIVE

Randomized controlled trials (RCTs) have a major role in the making of evidence-based guidelines. The aim of the present study was to critically appraise the RCTs that addressed nutritional interventions in patients with cystic fibrosis.

METHODS

Embase, PubMed, and the Cochrane Library were systematically searched until July 2015. Methodology and reporting of nutritional RCTs were evaluated by the Consolidated Standards of Reporting Trials (CONSORT) checklist and additional dimensions relevant to patients with CF.

RESULTS

Fifty-one RCTs were included. Full details on methods were provided in a minority of studies. The mean duration of intervention was <6 months. 56.9% of the RCTs did not define a primary outcome; 70.6% of studies did not provide details on sample size calculation; and only 31.4% reported on the subgroup or separated between important subgroups.

CONCLUSIONS

The examined RCTs were characterized by a weak methodology, a small number of patients with no sample size calculations, a relatively short intervention, and many times did not examine the outcomes that are important to the patient. Improvement over the years has been minor.

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.

Recombinant growth hormone therapy for cystic fibrosis in children and young adults

BACKGROUND

Cystic fibrosis is an inherited condition causing disease most noticeably in the lungs, digestive tract and pancreas. People with cystic fibrosis often have malnutrition and growth delay. Adequate nutritional supplementation does not improve growth optimally and hence an anabolic agent, recombinant growth hormone, has been proposed as a potential intervention.

OBJECTIVES

To evaluate the effectiveness and safety of recombinant human growth hormone therapy in improving lung function, quality of life and clinical status of children and young adults with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Date of latest search: 11 February 2015.We conducted a search of relevant endocrine journals and proceedings of the Endocrinology Society meetings using Scopus and Proceedings First. Date of latest search: 04 March 2015.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of all preparations of recombinant growth hormone compared to either no treatment, or placebo, or each other at any dose (high-dose and low-dose) or route and for any duration, in children or young adults aged up to 25 years diagnosed with cystic fibrosis (by sweat test or genetic testing).

DATA COLLECTION AND ANALYSIS

Two authors independently screened papers, extracted trial details and assessed their risk of bias.

MAIN RESULTS

Four controlled trials were included in this review (with 161 participants in total), each with an unclear risk of bias. Analysis of data obtained from these trials shows improvement in height for all comparisons, but improvements in weight and lean tissue mass were only reported in the comparison of standard dose recombinant growth hormone versus no treatment. One study showed moderate improvement at one time point in one parameter of pulmonary function tests, forced vital capacity (per cent predicted) when comparing standard dose recombinant growth hormone and no treatment, but there was no consistent benefit in lung function across all studies. Little evidence was found for improvement in quality of life. An improvement in fasting blood glucose levels was reported when comparing rhGH to placebo only. Exercise capacity improved in participants receiving standard dose recombinant growth hormone versus no treatment, but not for any other comparison. There is insufficient evidence to conclude any changes in hospitalisations, antibiotic use or significant adverse effects.

AUTHORS' CONCLUSIONS

Recombinant growth hormone therapy is effective in improving the intermediate outcomes in height, weight and lean tissue mass when compared with no treatment. One measure of pulmonary function test showed moderate improvement at a single time point, but no consistent benefit was seen across all studies. No significant changes in quality of life, clinical status or side-effects were observed in this review. Long-term, well-designed randomised controlled trials of recombinant growth hormone therapy in people with cystic fibrosis are required prior to evaluation of human growth hormone treatment for routine use.

Growth hormone improves short stature in children with Diamond-Blackfan anemia

BACKGROUND

Diamond-Blackfan anemia (DBA), an inherited marrow failure syndrome, has severe hypoplastic anemia in infancy and association with aplastic anemia, MDS/leukemia, and other malignancies. Short stature is present in most patients. Isolated cases have demonstrated improved growth on growth hormone (GH) therapy.

PROCEDURES

GH treatment data were obtained from 19 children with DBA (6 at our site and 13 from Genentech). Control data from 44 non-GH treated children were provided by Diamond Blackfan Anemia Registry. Annual growth velocity (GV) and height-for-age Z-scores (HAZ) were compared between groups and for up to 4y of GH treatment.

RESULTS

Constructed DBA-specific male and female height-for-age charts for non-GH treated patients revealed short stature compared to CDC norms. GH-treated patients had significantly lower HAZ prior to treatment initiation compared to non-GH-treated controls. Among GH-treated patients, GV significantly improved in the first two years relative to pre-treatment. HAZ significantly improved in each of 4y of GH therapy compared to baseline. After 2y of therapy, HAZ for GH-treated patients were not significantly different from controls, demonstrating successful catch-up growth.

CONCLUSIONS

GH treatment in children with DBA improves both GV and HAZ during treatment sustained for up to 4y. Very short children with DBA can be treated successfully with GH to restore stature to levels comparable to less affected patients. DBA height charts are useful tools for assessing age-specific growth in this typically short population. Careful consideration of individualized benefit of GH therapy versus risk is important in view of long-term underlying ∼5% malignancy risk in DBA.

Diagnosis and treatment of endocrine comorbidities in patients with cystic fibrosis

PURPOSE OF REVIEW

The aim of this review is to provide an update on various relevant endocrine aspects of care in adolescents and adults with cystic fibrosis.

RECENT FINDINGS

As life expectancy in cystic fibrosis has continuously improved, endocrine complications have become more apparent. The common endocrine complications include cystic fibrosis related diabetes, cystic fibrosis related bone disease, vitamin D deficiency and poor growth and pubertal development. Thyroid and adrenal disorders have also been reported, although the prevalence appears to be less common.

SUMMARY

Endocrine diseases are an increasingly recognized complication that has a significant impact on the overall health of individuals with cystic fibrosis. This review summarizes the updated screening and management of endocrine diseases in the cystic fibrosis population.

Appetite stimulants for people with cystic fibrosis

BACKGROUND

Chronic loss of appetite in cystic fibrosis concerns both individuals and families. Appetite stimulants have been used to help cystic fibrosis patients with chronic anorexia attain optimal body mass index and nutritional status. However, these may have adverse effects on clinical status.

OBJECTIVES

The aim of this review is to systematically search for and evaluate evidence on the beneficial effects of appetite stimulants in the management of CF-related anorexia and synthesize reports of any side-effects.

SEARCH METHODS

Trials were identified by searching the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register, MEDLINE, Embase, CINAHL, handsearching reference lists and contacting local and international experts.Last search of online databases: 01 April 2014.Last search of the Cystic Fibrosis Trials Register: 08 April 2014.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of appetite stimulants, compared to placebo or no treatment for at least one month in adults and children with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Authors independently extracted data and assessed the risk of bias within eligible trials. Meta-analyses were performed.

MAIN RESULTS

Three trials (total of 47 recruited patients) comparing appetite stimulants (cyproheptadine hydrochloride and megesterol acetate) to placebo were included; the numbers of adults or children within each trial were not always reported. The risk of bias of the included trials was graded as moderate.A meta-analysis of all three trials showed appetite stimulants produced a larger increase in weight z score at three months compared to placebo, mean difference 0.61 (95% confidence interval 0.29 to 0.93) (P < 0.001) (n = 40) with no evidence of a difference in effect between two different appetite stimulants. One of these trials also reported a significant weight increase with megesterol acetate compared to placebo at six months (n = 17). The three trials reported no significant differences in forced expiratory volume at one second (per cent predicted) between the appetite stimulant groups and placebo at follow up, with durations ranging from two to nine months. A meta-analysis of two trials showed a significantly higher proportion of patients reporting increased appetite, odds ratio 45.25 (95% confidence interval 3.57 to 573.33) (P = 0.003) (n = 23), but the frequency of reported side effects was undetermined.

AUTHORS' CONCLUSIONS

In the short term (six months) in adults and children, appetite stimulants improved only two of the outcomes in this review - weight (or weight z score) and appetite; and side effects were insufficiently reported to determine the full extent of their impact. Whilst the data may suggest the potential use of appetite stimulants in treating anorexia in adults and children with cystic fibrosis, this is based upon moderate quality data from a small number of trials and so this therapy cannot be conclusively recommended based upon the findings in the review. Clinicians need to be aware of the potential adverse effects of appetite stimulants and actively monitor any patients prescribed these medications accordingly.Research is needed to determine meaningful surrogate measures for appetite and define what constitutes quality weight gain. Future trials of appetite stimulants should use a validated measure of symptoms including a disease-specific instrument for measuring poor appetite. This review highlights the need for multicentred, adequately powered and well-designed trials to evaluate agents to safely increase appetite in people with cystic fibrosis and to establish the optimal mode of treatment.

Recombinant growth hormone therapy for cystic fibrosis in children and young adults

BACKGROUND

Cystic fibrosis is an inherited condition causing disease most noticeably in the lungs, digestive tract and pancreas. People with cystic fibrosis often have malnutrition and growth delay. Adequate nutritional supplementation does not improve growth optimally and hence an anabolic agent, recombinant growth hormone, has been proposed as a potential intervention.

OBJECTIVES

To evaluate the effectiveness and safety of recombinant human growth hormone therapy in improving lung function, quality of life and clinical status of children and young adults with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Date of latest search: 15 May 2013.We conducted a search of relevant endocrine journals and proceedings of the Endocrinology Society meetings using Scopus and Proceedings First. Date of latest search: 15 March 2012.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of all preparations of recombinant growth hormone compared to either no treatment, or placebo, or each other at any dose (high-dose and low-dose) or route and for any duration, in children or young adults aged up to 25 years diagnosed with cystic fibrosis (by sweat test or genetic testing).

DATA COLLECTION AND ANALYSIS

Two authors independently screened papers, extracted trial details and assessed their risk of bias.

MAIN RESULTS

Four controlled trials were included in this review (with 161 participants in total), each with an unclear risk of bias. Analysis of data obtained from these trials shows improvement in height for all comparisons, but improvements in weight and lean tissue mass were only reported in the comparison of standard dose recombinant growth hormone versus no treatment. There is moderate improvement in one parameter of pulmonary function tests, functional vital capacity (per cent predicted) when comparing standard dose recombinant growth hormone and no treatment. Little evidence was found for improvement in quality of life. An improvement in fasting blood glucose levels was reported when comparing rhGH to placebo only. Exercise capacity improved in participants receiving standard dose recombinant growth hormone versus no treatment, but not for any other comparison. There is insufficient evidence to conclude any changes in hospitalisations, antibiotic use or significant adverse effects.

AUTHORS' CONCLUSIONS

Recombinant growth hormone therapy is effective in improving the intermediate outcomes in height, weight and lean tissue mass when compared with no treatment. One measure of pulmonary function test showed moderate improvement. No significant changes in quality of life, clinical status or side-effects were observed in this review. Long-term, well-designed randomised controlled trials of recombinant growth hormone therapy in patients with cystic fibrosis are required prior to evaluation of human growth hormone treatment for routine use in patients.

Growth and growth hormone treatment in children with chronic diseases

Growth hormone has been available for treatment of various conditions for over 50 years. There have been a number of chronic disease states in which it has been used, such as chronic kidney disease, which became a US Food and Drug Administration (FDA)-approved indication in 1993. For other chronic disease states there have been clinical studies supporting its use, but they have not yet been approved as a indications by the FDA. Examples of such diseases are cystic fibrosis, chronic arthritis, short bowel syndrome, burn trauma, and hypophosphatemic rickets.

[Growth hormone in children and adolescents with cystic fibrosis]

The recombinant human growth hormone (rhGH) can improve weight gain, physical growth, clinical and lung in cystic fibrosis (CF). However, the routine use, although promising, is not established in the literature. The objective of this study was to assess the benefits of rhGH in children and adolescents with CF. We conducted a systematic review in the database PubMed, Lilacs, SciELO and Cochrane, in the period 2000-2010, using the keywords: "cystic fibrosis", "growth hormone", "children" and "adolescents". We found 77 articles and included 11 randomized controlled trials, with 290 children and adolescents with CF. The short-term use (1-24 months) of rhGH improved the height, weight, growth rate, bone mineral content and components of pulmonary function. Adverse effects, like diabetes, were not observed in the studies. The short-term use of rhGH improved growth and body composition in patients with CF.

Emerging options in growth hormone therapy: an update

Growth hormone (GH) was first used to treat a patient in 1958. For the next 25 years it was available only from cadaver sources, which was of concern because of safety considerations and short supply. In 1985, GH produced by recombinant DNA techniques became available, expanding its possible uses. Since that time there have been three indications approved by the US Food and Drug Administration (FDA) for GH-deficiency states and nine indications approved for non-GH-deficiency states. In 2003 the FDA approved GH for use in idiopathic short stature (ISS), which may indirectly cover other diagnoses that have short stature as a feature. However, coverage for GH therapy is usually more reliably obtainable for a specific indication, rather than the ISS indication. Possible future uses for GH therapy could include the treatment of syndromes such as Russell-Silver syndrome or chondrodystrophy. Other non-short-stature indications could include wound healing and burns. Other uses that have been poorly studied include aging and physical performance, in spite of the interest already shown by elite athletes in using GH. The safety profile of GH developed over the past 25 years has shown it to be a very safe hormone with few adverse events associated with it. The challenge for the future is to follow these patients into adulthood to determine whether GH therapy poses any long-term risks.

Treatment of short stature and growth hormone deficiency in children with somatotropin (rDNA origin)

Somatotropin (growth hormone, GH) of recombinant DNA origin has provided a readily available and safe drug that has greatly improved management of children and adolescents with GH deficiency (GHD) and other disorders of growth. In the US and Europe, regulatory agencies have given approval for the use of GH in children and adults who meet specific criteria. However, clinical and ethical controversies remain regarding the diagnosis of GHD, dosing of GH, duration of therapy and expected outcomes. Areas which also require consensus include management of pubertal patients, transitioning pediatric patients to adulthood, management of children with idiopathic short stature and the role of recombinant IGF-1 in treatment. Additionally, studies have demonstrated anabolic benefits of GH in children who have inflammatory-based underlying disease and efficacy of GH in overcoming growth delays in people treated chronically with corticosteroids. These areas are open for possible new uses of this drug. This review summarizes current indications for GH use in children and discusses areas of clinical debate and potential anabolic uses in chronic illness.

A roadmap to the brittle bones of cystic fibrosis

Cystic fibrosis (CF) is an autosomal recessive disorder which despite advances in medical care continues to be a life-limiting and often fatal disease. With increase in life expectancy of the CF population, bone disease has emerged as a common complication. Unlike the osteoporosis seen in postmenopausal population, bone disease in CF begins at a young age and is associated with significant morbidity due to fractures, kyphosis, increased pain, and decreased lung function. The maintenance of bone health is essential for the CF population during their lives to prevent pain and fractures but also as they approach lung transplantation since severe bone disease can lead to exclusion from lung transplantation. Early recognition, prevention, and treatment are key to maintaining optimal bone health in CF patients and often require a multidisciplinary approach. This article will review the pathophysiology, current clinical practice guidelines, and potential future therapies for treating CF-related bone disease.

Recombinant human growth hormone in the treatment of patients with cystic fibrosis

CONTEXT

Recombinant human growth hormone (rhGH) improves growth in patients with growth hormone deficiency or idiopathic short stature. Its role in patients with cystic fibrosis (CF) is unclear.

OBJECTIVE

To review the effectiveness of rhGH in the treatment of patients with CF.

METHODS

Medline and the Cochrane Central Register of Controlled Trials were searched from the earliest date through April 2010. Randomized controlled trials, observational studies, systematic reviews/meta-analyses, or case reports were included if rhGH therapy was administered to patients with CF and data on prespecified harms, intermediate outcomes, or final health outcomes were reported. When applicable, end points were pooled by using a random-effects model. The overall body of evidence was graded for each outcome as insufficient, low, moderate, or high.

RESULTS

Ten unique controlled trials (n = 312) and 8 observational studies (n = 58) were included. On quantitative synthesis of controlled trials, several markers of pulmonary function, anthropometrics, and bone mineralization were significantly improved versus control. Results of single-arm observational studies for the aforementioned outcomes were generally supportive of findings in clinical trials. There is insufficient evidence to determine the effect of rhGH on intravenous antibiotic use during therapy, pulmonary exacerbations, health-related quality-of-life, bone consequences, or total mortality, but moderate evidence suggests that rhGH therapy reduces the rate of hospitalization versus control.

CONCLUSIONS

rhGH improved almost all intermediate measures of pulmonary function, height, and weight in patients with CF. Improvements in bone mineral content are also promising. However, with the exception of hospitalizations, the benefits on final health outcomes cannot be directly determined at this time.

The long term efficacy of gastrostomy feeding in children with cystic fibrosis on anthropometric markers of nutritonal status and pulmonary function

The clinical outcomes from 14 children (7 male) with cystic fibrosis (CF) who had a gastrostomy tube inserted between January 1999 and August 2005 are presented. The mean age of gastrostomy insertion was 6.63 years. All patients had pancreatic insufficiency with mildly compromised lung function (mean FEV1 71%). Data was collected for 1 year prior and 2 years post commencement of gastrostomy feeding. Subjects experienced a significant decline in both weight and height for the 12 months prior to enteral feeding. There was a significant improvement in some anthropometric parameters but not respiratory function in the first 12 months of feeding which then plateau during the second year. These results also highlight the benefit of using height and weight Z scores rather than the measuring of the BMI as an indicator of nutritional change in children with CF.

Insulin-like growth factor-I levels predict weight, height and protein catabolism in children and adolescents with cystic fibrosis

Multiple reports have demonstrated the benefit of growth hormone (GH) treatment in children with cystic fibrosis (CF) and previous studies have demonstrated low to normal insulin-like growth factor-I (IGF-I) levels in these patients. Most biological effects of GH are mediated by IGF-I; however, the relationship between height, weight and rate of growth has not been systematically studied in CF. We conducted a retrospective analysis of 52 patients (including control volunteers with CF) who had participated in previous studies of GH treatment to determine the relationship between levels of IGF-I and growth in children with CF. In a subset of these patients, we also evaluated the relationship between protein catabolism and IGF-I. Baseline IGF-I levels and IGF-I z-scores were correlated with same day measures of height, weight, height and weight z-scores. In a subset of patients, IGF-I levels were also correlated with leucine rate of appearance (a measure of protein catabolism). IGF-I levels were obtained every six months during our studies and were correlated with same day height, weight and protein turnover. Height and weight velocity were calculated every six months from study baseline and were correlated with IGF-I levels. In all patients, whether treated with GH or controls, we found a positive linear correlation between IGF-I levels and height (r = 0.66, p < 0.0001) and weight (r = 0.61, p < 0.0001), as well as height and weight velocity. There was also a strong relationship between leucine rate of appearance and IGF-I. These results suggest a strong correlation between IGF-I and height, weight and protein catabolism and emphasize the need to normalize IGF-I levels in children with cystic fibrosis.

Murine model for cystic fibrosis bone disease demonstrates osteopenia and sex-related differences in bone formation

As the incidence of cystic fibrosis (CF) bone disease is increasing, we analyzed CF transmembrane conductance regulator (CFTR) deficient mice (CF mice) to gain pathogenic insights. In these studies comparing adult (14 wk) CF and C57BL/6J mice, both bone length and total area were decreased in CF mice. Metaphyseal trabecular and cortical density were also decreased, as well as diaphyseal cortical and total density. Trabecular bone volume was diminished in CF mice. Female CF mice revealed decreased trabecular width and number compared with C57BL/6J, whereas males demonstrated no difference in trabecular number. Female CF mice had reduced mineralizing surface and bone formation rates. Conversely, male CF mice had increased mineralizing surface, mineral apposition, and bone formation rates compared with C57BL/6J males. Bone formation rate was greater in males compared with female CF mice. Smaller bones with decreased density in CF, despite absent differences in osteoblast and osteoclast surfaces, suggest CF transmembrane conductance regulator influences bone cell activity rather than number. Differences in bone formation rate in CF mice are suggestive of inadequate bone formation in females but increased bone formation in males. This proanabolic observation in male CF mice is consistent with other clinical sex differences in CF.

Growth and nutrition disorders in children with cerebral palsy

Growth and nutrition disorders are common secondary health conditions in children with cerebral palsy (CP). Poor growth and malnutrition in CP merit study because of their impact on health, including psychological and physiological function, healthcare utilization, societal participation, motor function, and survival. Understanding the etiology of poor growth has led to a variety of interventions to improve growth. One of the major causes of poor growth, malnutrition, is the best-studied contributor to poor growth; scientific evidence regarding malnutrition has contributed to improvements in clinical management and, in turn, survival over the last 20 years. Increased recognition and understanding of neurological, endocrinological, and environmental factors have begun to shape care for children with CP, as well. The investigation of these factors relies on advances made in the assessment methods available to address the challenges inherent in measuring growth in children with CP. Descriptive growth charts and norms of body composition provide information that may help clinicians to interpret growth and intervene to improve growth and nutrition in children with CP. Linking growth to measures of health will be necessary to develop growth standards for children with CP in order to optimize health and well-being.

[Growth hormone therapy for children with chronic diseases]

Growth disorders are commonly observed in children suffering from chronic diseases. The pathogenesis of growth failure is multifactorial. In chronic inflammatory diseases such as juvenile idiopathic arthritis and inflammatory bowel disease, growth is also affected by pro-inflammatory cytokines. Patients with chronic diseases might also become growth hormone (GH) deficient. However, normal or increased GH secretion with reduced plasma concentrations of insulin-like growth factor-I indicate a degree of GH insensitivity in some patients. Growth damage can increase with specific treatments, especially if glucocorticoids are used. GH therapy has been used to reduce the consequences of the disease and long-term steroid therapy in these patients. In this review, it is reported the encouraging results of GH treatment in growth-retarded children with chronic diseases, both in well defined indications as well in situations still under investigation.

Appetite stimulants use in cystic fibrosis

Cystic fibrosis (CF) is an autosomal recessive disease. It affects multiple body organs. The lungs and pancreas are the most affected which results in progressive lung damage and pancreatic insufficiency. Due to the disease process, CF patients require significantly higher caloric intake than recommended for other individuals. The nutritional goal for CF patients is to achieve normal growth and development and, once genetic potential is reached, to maintain good nutritional status throughout life. Evidence has shown that lung function is closely associated with nutritional status in CF and that nutritional status is an independent predictor of survival. Most CF patients are on a high calorie diet to help achieve normal growth and development and maintain good lung function. Inadequate caloric intake in CF can lead to malnutrition. Malnutrition in CF requires careful, multidisciplinary history taking, physical exam, and overall patient/family assessment. Only by determining the actual cause of the malnutrition can appropriate and safe therapies be used to treat it. Appetite stimulants, although efficacious in treating malnutrition in CF, should only be prescribed if decreased food intake secondary to inadequate appetite is the principal cause of the malnutrition and all other contributing factors have been assessed, ruled-out or treated. In this review, we attempted to summarize the use of several appetite stimulants used in CF and other diseases to improve appetite and maximize caloric intake.

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.

A multicenter, randomized, double-blind, placebo-controlled trial to evaluate the metabolic and respiratory effects of growth hormone in children with cystic fibrosis

OBJECTIVE

Positive effects of growth hormone therapy on growth, nutritional status, and lung function have been observed in patients with cystic fibrosis, but the current evidence is based on unblinded studies that involved a small number of patients. This trial was designed as a multicenter, randomized, placebo-controlled, double-blind study to assess the efficacy and safety of 2 dosages of growth hormone in cystic fibrosis.

METHODS

Sixty-three dystrophic patients with cystic fibrosis were randomly assigned for 24 weeks to 1 of 3 treatment arms: growth hormone dosage of 0.11 IU/kg body weight per day, growth hormone dosage of 0.21 IU/kg body weight per day, or placebo. The 24-week double-blind period was followed by an open treatment period of 24 weeks. The primary outcome measure was the change in forced expiratory volume in 1 second in percentage predicted from baseline. Secondary outcome measures were changes in height, weight, and exercise tolerance.

RESULTS

Height, growth velocity, and growth factors (insulin-like growth factor 1 and insulin-like growth factor-binding protein 3) increased significantly in both treatment groups, whereas weight gain did not differ between the growth hormone groups and placebo. A trend toward improvement in absolute forced vital capacity was observed in patients who received the higher growth hormone dosage, whereas forced expiratory volume in 1 second did not change significantly with growth hormone treatment. Maximal oxygen uptake during peak exercise increased significantly in treated patients. There were no significant differences in the frequency or severity of adverse effects or in the incidence of abnormalities in glucose metabolism.

CONCLUSIONS

These data suggest that in the group investigated, growth hormone therapy was well tolerated and had positive metabolic effects but did not result in short-term improvement of lung function in patients with cystic fibrosis.

Twenty years of recombinant human growth hormone in children: relevance to pediatric care providers

Recombinant human growth hormone has revolutionized the management of children and adolescents with growth hormone deficiency and other growth disorders, but clinical and ethical controversies remain regarding diagnostic approach, optimal recombinant human growth hormone dose and duration, and expected outcomes. Management of pubertal and transitioning patients with growth hormone deficiency has also commanded increased attention. Recent clinical studies that demonstrate the positive health benefits of recombinant human growth hormone in children with cystic fibrosis, inflammatory bowel disease, and juvenile rheumatoid arthritis have not yet clarified issues about patient selection and appropriate long-term use. An understanding of current recombinant human growth hormone indications and controversies can facilitate patient evaluation and expedite referral for potential treatment. This review summarizes current indications for recombinant human growth hormone use, discusses clinical challenges, and provides recommendations for pediatricians caring for children who may be appropriate candidates for recombinant human growth hormone therapy.

Update on maintaining bone health in cystic fibrosis

PURPOSE OF REVIEW

The high prevalence of decreased bone density in adults with cystic fibrosis is now well recognized, and guidelines for screening and treatment of cystic fibrosis-related bone disease have recently been published. This review summarizes the current best practices for optimizing bone health in cystic fibrosis and highlight recent findings that provide insight into the etiology of cystic fibrosis-related bone disease.

RECENT FINDINGS

Recent research suggests that cystic fibrosis-related bone disease actually starts during childhood, when individuals with cystic fibrosis fail to demonstrate normal bone calcium accretion. The failure to reach peak bone mass is made worse by increased osteoclast activity and bone resorption. This combination results in decreased bone density and an increased risk of fracture. Recent clinical studies suggest that multiple contributing factors need to be addressed in cystic fibrosis to optimize bone health: malnutrition, vitamin and mineral malabsorption, recurrent infections, inadequate sex hormones, and lack of exercise. Oral bisphosphonates have been demonstrated to be effective in cystic fibrosis and should be used when osteoporosis or progressive osteopenia is present.

SUMMARY

Research suggests cystic fibrosis-related bone disease actually begins during childhood, and guidelines now exist to aid in identifying and treating those with decreased bone density.