Evidence-based practice recommendations for nutrition-related management of children and adults with cystic fibrosis and pancreatic insufficiency: results of a systematic review. ACTA ACUST UNITED AC. 2008;108:832-839. [PMID: 18442507 DOI: 10.1016/j.jada.2008.02.020]

Pancreatic enzyme products: digesting the changes

OBJECTIVE

To review the pharmacology, dosage regimens, efficacy, and safety of currently marketed pancreatic enzyme products (PEPs).

DATA SOURCES

Studies were identified by PubMed (1966-January 2011), clinicaltrials.gov, fda.gov, and International Pharmaceutical Abstracts. Search terms included pancreatic enzyme, lipase, Creon, Zenpep, Pancreaze, and exocrine pancreatic insufficiency (EPI).

STUDY SELECTION AND DATA EXTRACTION

All human studies evaluating the efficacy of currently approved or potential PEPs were reviewed.

DATA SYNTHESIS

PEPs are composed of porcine lipase, amylase, and protease and are used in patients with EPI secondary to cystic fibrosis, chronic pancreatitis, and pancreatectomy. In 1938, PEPs were exempted from the Food, Drug, and Cosmetic Act of 1938 and never underwent a formal Food and Drug Administration (FDA) review process. In response to reports of treatment failures during product interchange, the FDA conducted a review of available PEP products. This review found a large variability of response between the unapproved PEP products, which resulted in the FDA requiring approval of all PEP products by April 2010. The 3 delayed-release, enteric-coated PEPs currently approved by the FDA (Creon, Zenpep, and Pancreaze) have demonstrated efficacy and safety in EPI secondary to cystic fibrosis. Creon has also demonstrated safety and efficacy in EPI secondary to chronic pancreatitis and pancreatectomy. Cost difference between the 3 products is minimal. Treatment-related adverse events in clinical studies for all PEPs were less than or similar to those with placebo.

CONCLUSIONS

At this time, Creon is an appropriate first-line agent, as it has been approved for chronic pancreatitis, pancreatectomy, and cystic fibrosis.

Mild CFTR mutations and genetic predisposition to lactase persistence in cystic fibrosis

Taking into account the reported incidence of hypolactasia in cystic fibrosis (CF) and the possible impact of milk products on nutritional status we aimed to assess the genetic predisposition to adult-type hypolactasia (ATH) and its incidence in CF. Single nucleotide polymorphism upstream of the lactase gene (LCT) was assessed in 289 CF patients. In subject with -13910C/C genotype (C/C) predisposing to ATH, hydrogen-methane breath test (BT) with lactose loading was conducted and clinical symptoms typical for lactose malabsorption were assessed. The percentage of CF patients with C/C was similar to that observed in healthy subjects (HS) (31.5 vs 32.5% ). Eleven out of 52 (24.5%) CF C/C patients had abnormal BT results. The recalculated frequency of lactose malabsorption was similar for the entire CF and HS populations (6.9 vs 7.2%). Similarly as in the control group, few CF patients have identified and linked to lactose consumption clinical symptoms. The frequency of LCT polymorphic variants in CF patients having and not having severe mutations of CFTR gene showed significant differences. The C allele was more frequent in homozygotes of the severe mutations than in patients carrying at least one mild/unknown mutation (P<0.0028) and in patients with at least one mild mutation (P < 0.0377). In conclusion, CF patients carrying mild CFTR mutations seem to have lower genetic predisposition to ATH. Lactose malabsorption due to ATH in CF is not more frequent than in the general population. Symptomatic assessment of lactose malabsorption in CF is not reliable.

Managing cystic fibrosis: strategies that increase life expectancy and improve quality of life

The survival of patients with cystic fibrosis (CF) continues to improve. The discovery and cloning of the CFTR gene more than 21 years ago led to the identification of the structure and function of the CFTR chloride channel. New therapies based on the understanding of the function of CFTR are currently under development. The better clinical status and improved survival of patients with CF is not only a result of understanding of the molecular mechanisms of CF but also a result of the development of therapeutic strategies that are based on insights into the natural course of the disease. Current CF treatments that target respiratory infections, inflammation, mucociliary clearance, and nutritional status are associated with improved pulmonary function and reduced exacerbations. Patients benefit from treatment at a specialized CF center by a multidisciplinary dedicated team with emphasis being placed on frequent visits, periodic testing, and monitoring adherence to therapy. The purpose of this review is to survey recent developments in CF care that are responsible for the improved survival and quality of life of patients with CF.

The effects of an intensive behavior and nutrition intervention compared to standard of care on weight outcomes in CF

Inadequate intake and suboptimal growth are common problems for patients with CF and a critical target for intervention. The purpose of this study was to compare the growth outcomes of children with CF who participated in a randomized clinical trial to improve energy intake and weight to children with CF receiving standard of care during the same time period. Our primary outcome was change in body mass index z-score (BMI z-score) over 2 years. An exploratory outcome was forced expiratory volume at 1-sec (FEV(1) ) over 2 years. Participants were children ages 4-12 with CF, who participated in a randomized clinical trial of behavior plus nutrition intervention versus nutrition education alone, and a matched Comparison Sample receiving standard of care drawn from the Cystic Fibrosis Foundation (CFF) Registry. Children in the Clinical Trial Group (N=67) participated in a 9-week, nutrition intervention and were followed at regular intervals (3, 6, 12, 18, and 24 months) for 2 years post-treatment to obtain anthropometric and pulmonary function data. For each child in the Comparison Sample (N=346), these measures were obtained from the CFF Registry at matching intervals for the 27-month period corresponding to the clinical trial. Over 27 months, children in the Clinical Trial Group (the combined sample of the behavior plus nutrition and the nutrition alone) demonstrated significantly less decline in BMI z-score, -0.05 (SD=0.68, CI= -0.23 to 0.13), as compared to children in the Comparison Sample, -0.21 (SD=0.67, CI= -0.31 to -0.11). No statistically significant differences were found for decline in FEV(1) between children in the Clinical Trial Group and the Comparison Sample. The key implication of these findings is that intensive behavioral and nutritional intervention is effective and needs to be adapted so that it can be broadly disseminated into clinical practice.

Trends in the use of routine therapies in cystic fibrosis: 1995-2005

Many therapies are used to treat manifestations of cystic fibrosis (CF). Trends in routine therapy use in Epidemiologic Study of Cystic Fibrosis patients were studied from 1995 to 2005. Patients (15,087) were assessed in 1995; 12,778 in 2005. Observed differences in therapy use of ≥2% were statistically significant at P < 0.001. Comparing the 1995 and 2005 populations, mean age was 13.9 versus 15.5 years; weight-for-age percentile was 30.3 versus 36.9; and mean forced expiratory volume in 1 sec (FEV(1)) was 73.7% (n = 7065) versus 78.7% (n = 7867) predicted. Use of several therapies increased, including airway clearance (69.9-89.6%), inhaled bronchodilators (72.0-84.0%), dornase alfa (44.8-67.2%), inhaled corticosteroids (16.0-49.3%), inhaled antibiotics (6.5-43.1%), oral nutritional supplements (18.3-24.5%), and insulin/oral hypoglycemic agents (4.9-10.2%). Use of mast cell stabilizers (from 22.0% to 5.3%) and oral bronchodilators (from 10.4% to 1.5%) decreased. Less dramatic changes occurred for pancreatic enzymes (92.6-91.0%), oral nonquinolone antibiotics (44.7-39.8%), oral corticosteroids (7.8-5.2%), mucolytics (4.4-2.5%), NSAIDs/high-dose ibuprofen (3.6-3.3%), enteral nutrition (5.2% vs. 8.2%), and oxygen (4.7-4.5%). Therapies not tracked in 1995 were evident in 2005, including oral macrolide antibiotics (33.8%), leukotriene inhibitors/antagonists (10.8%), and inhaled hypertonic saline (2.6%). Routine therapies were generally used more often by older patients and those with lower FEV(1). Notable increases in use of therapies, particularly of inhaled therapies, suggest that overall patient treatment burden must have risen correspondingly.

CREON (Pancrelipase Delayed-Release Capsules) for the treatment of exocrine pancreatic insufficiency

Exocrine pancreatic insufficiency (EPI) is associated with conditions including cystic fibrosis (CF), chronic pancreatitis (CP), and pancreatic surgery (PS). The symptoms include maldigestion, malnutrition, weight loss, flatulence, and steatorrhea. Pancreatic enzyme replacement therapy (PERT) is the standard treatment for EPI; it is regulated in many countries and most recently in the USA following a US FDA mandate for all PERT manufacturers to submit new drug applications. Pancrelipase delayed-release capsules (CREON®, Abbott, Marietta, GA, USA) have been available in Europe since 1984 and in the USA since 1987; a new formulation was the first PERT to gain approval in the USA in 2009. The efficacy and safety of CREON have been demonstrated in double-blind, randomized, placebo-controlled trials in patients with CF aged ≥7 years and in patients with CP or post-PS. The data consistently demonstrate significantly better fat and nitrogen absorption with CREON versus placebo, and improvements in clinical symptoms, stool frequency, and body weight. Additionally, efficacy and safety of CREON have been shown in open-label studies in young children with CF (aged 1 month to 6 years), with control of fat malabsorption and control of clinical symptoms. The most commonly reported adverse events (AEs) with PERT are gastrointestinal disorders and allergic skin reactions. In clinical studies, CREON was well tolerated with very few withdrawals due to AEs and a low frequency of AEs judged treatment related, regardless of patient age. To further support the known safety profile of PERT, all manufacturers are required to investigate risk factors for fibrosing colonopathy, a rare gastrointestinal complication of CF, and the theoretical risk of viral transmission from porcine-derived PERT products. Together, the clinical study data and wealth of clinical experience suggest that CREON is effective and safe in patients with EPI regardless of etiology, with a very favorable risk-benefit profile.

Management of pancreatic exocrine insufficiency: Australasian Pancreatic Club recommendations

Pancreatic exocrine insufficiency (PEI) occurs when the amounts of enzymes secreted into the duodenum in response to a meal are insufficient to maintain normal digestive processes. The main clinical consequence of PEI is fat maldigestion and malabsorption, resulting in steatorrhoea. Pancreatic exocrine function is commonly assessed by conducting a 3-day faecal fat test and by measuring levels of faecal elastase-1 and serum trypsinogen. Pancreatic enzyme replacement therapy is the mainstay of treatment for PEI. In adults, the initial recommended dose of pancreatic enzymes is 25,000 units of lipase per meal, titrating up to a maximum of 80,000 units of lipase per meal. In infants and children, the initial recommended dose of pancreatic enzymes is 500 units of lipase per gram of dietary fat; the maximum daily dose should not exceed 10,000 units of lipase per kilogram of bodyweight. Oral pancreatic enzymes should be taken with meals to ensure adequate mixing with the chyme. Adjunct therapy with acid-suppressing agents may be useful in patients who continue to experience symptoms of PEI despite high-dose enzyme therapy. A dietitian experienced in treating PEI should be involved in patient management. Dietary fat restriction is not recommended for patients with PEI. Patients with PEI should be encouraged to consume small, frequent meals and to abstain from alcohol. Medium-chain triglycerides do not provide any clear nutritional advantage over long-chain triglycerides, but can be trialled in patients who fail to gain or to maintain adequate bodyweight in order to increase energy intake.

TLR5 as an anti-inflammatory target and modifier gene in cystic fibrosis

New treatments are needed to improve the health of people with cystic fibrosis (CF). Reducing lung-damaging inflammation is likely to be beneficial, but specific anti-inflammatory targets have not been identified. By combining cellular immunology with a population-based genetic modifier study, we examined TLR5 as an anti-inflammatory target and modifier gene in CF. Using two pairs of human CF and control airway epithelial cells, we demonstrated that the TLR5-flagellin interaction is a major mediator of inflammation following exposure to Pseudomonas aeruginosa. To validate TLR5 as an anti-inflammatory target, we analyzed the disease modifying effects of the TLR5 c.1174C>T single nucleotide polymorphism (rs5744168) in a large cohort of CF patients (n = 2219). rs5744168 encodes a premature stop codon and the T allele is associated with a 45.5-76.3% reduction in flagellin responsiveness (p < 0.0001). To test the hypothesis that reduced TLR5 responsiveness would be associated with improved health in CF patients, we examined the relationship between rs5744168 and two clinical phenotypes: lung function and body weight. Adults with CF carrying the TLR5 premature stop codon (CT or TT genotype) had a higher body mass index than did CF patients homozygous for the fully functional allele (CC genotype) (p = 0.044); however, similar improvements in lung function associated with the T allele were not statistically significant. Although follow-up studies are needed to confirm the impact of TLR5 on nutritional status, this translational research provides evidence that genetic variation in TLR5 resulting in reduced flagellin responsiveness is associated with improved health indicators in adults with CF.

We can handle this: parents' use of religion in the first year following their child's diagnosis with cystic fibrosis

The diagnosis of a child's life-shortening disease leads many American parents to utilize religious beliefs. Models relating religious constructs to health have been proposed. Still lacking are inductive models based on parent experience. The specific aims of this study were: 1. develop a grounded theory of parental use of religion in the year after diagnosis; 2. describe whether parents understand a relationship between their religious beliefs and their follow-through with their child's at-home treatment regimen. Fifteen parent interviews were analyzed using grounded theory method. Parents used religion to make meaning of their child's cystic fibrosis (CF) diagnosis. Parents imagined God as active, benevolent, and interventionist; found hope in their beliefs; felt supported by God; and related religion to their motivation to adhere to their child's treatment plan. Religious beliefs are clinically significant in working with many parents of children recently diagnosed with CF. Interventions that improve adherence to treatment may be enhanced by including religious aspects.

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.

Metabolomic profiling reveals biochemical pathways and biomarkers associated with pathogenesis in cystic fibrosis cells

Cystic fibrosis (CF) is a life-shortening disease caused by a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. To gain an understanding of the epithelial dysfunction associated with CF mutations and discover biomarkers for therapeutics development, untargeted metabolomic analysis was performed on primary human airway epithelial cell cultures from three separate cohorts of CF patients and non-CF subjects. Statistical analysis revealed a set of reproducible and significant metabolic differences between the CF and non-CF cells. Aside from changes that were consistent with known CF effects, such as diminished cellular regulation against oxidative stress and osmotic stress, new observations on the cellular metabolism in the disease were generated. In the CF cells, the levels of various purine nucleotides, which may function to regulate cellular responses via purinergic signaling, were significantly decreased. Furthermore, CF cells exhibited reduced glucose metabolism in glycolysis, pentose phosphate pathway, and sorbitol pathway, which may further exacerbate oxidative stress and limit the epithelial cell response to environmental pressure. Taken together, these findings reveal novel metabolic abnormalities associated with the CF pathological process and identify a panel of potential biomarkers for therapeutic development using this model system.

Managing diabetes in cystic fibrosis

Cystic fibrosis related diabetes (CFRD) is the most common co-morbidity in persons with cystic fibrosis (CF). As the life expectancy of persons with CF continues to increase, the need to proactively diagnose and aggressively treat CFRD and its potential complications has become more apparent. CFRD negatively impacts lung function, growth and mortality, making its diagnosis and management crucial in a population already at high risk for early mortality. Compared to type 1 and type 2 diabetes, CFRD is a unique entity, requiring a thorough understanding of its unique pathophysiology to facilitate the creation and utilization of an effective medical treatment plan. The physiology of CFRD is complex, likely consisting of a combination of insulin deficiency, insulin resistance and a genetic predisposition towards the development of diabetes. However, the hallmark of CFRD is insulin deficiency, necessitating the use of exogenous insulin as the mainstay of therapy. Insulin administration, in combination with a multidisciplinary team of health professionals with expertise in the care of patients with CF and CFRD, is the cornerstone of the care for these patients. The goals of treatment of the CFRD population are to reverse protein catabolism, maintain a healthy weight, and reduce acute and chronic diabetes complications. Creating a partnership between the treatment team and the patient is the ideal way to accomplish these goals and is essential for successful diabetes care.

Hypoventilation syndromes

A wide variety of mechanisms can lead to the hypoventilation associated with various medical disorders, including derangements in central ventilatory control, mechanical impediments to breathing, and abnormalities in gas exchange leading to increased dead space ventilation. The pathogenesis of hypercapnia in obesity hypoventilation syndrome remains somewhat obscure, although in many patients comorbid obstructive sleep apnea appears to play an important role. Hypoventilation in neurologic or neuromuscular disorders is primarily explained by weakness of respiratory muscles, although some central nervous system diseases may affect control of breathing. In other chest wall disorders, obstructive airways disease, and cystic fibrosis, much of the pathogenesis is explained by mechanical impediments to breathing, but an element of increased dead space ventilation also often occurs. Central alveolar hypoventilation syndrome involves a genetically determined defect in central respiratory control. Treatment in all of these disorders involves coordinated management of the primary disorder (when possible) and, increasingly, the use of noninvasive positive pressure ventilation.

Treatment of pulmonary exacerbations in adult cystic fibrosis patients: a review

Cystic fibrosis (CF) is a complex multisystemic disease requiring specialized care. It is characterized by progressive pulmonary decline, with intermittent worsening of lung function, often called pulmonary exacerbations. Eighty-five percent of all deaths from CF are a result of pulmonary disease, and pulmonary exacerbations are associated with decline in lung function. Treating pulmonary exacerbations requires a multifaceted approach and includes a multidisciplinary team composed of a physician, nurse, respiratory therapist, physical therapist, and nutritionist. Recently, the Cystic Fibrosis Foundation published guidelines addressing the comprehensive treatment of pulmonary exacerbations. This article outlines the treatment goals established by these guidelines, including the evaluation and treatment of comorbid conditions (eg, CF-related diabetes) and serious complications associated with CF exacerbations (eg, pneumothorax). Proper treatment of pulmonary exacerbations in CF patients will continue to improve their health and quality of life.

Chemosensory function and food preferences of children with cystic fibrosis

A major problem for patients with cystic fibrosis (CF) is the maintenance of adequate nutrition to maintain normal growth. The hypotheses that poor nutrition could be due to smell and/or taste dysfunction has been pursued in several studies with contradictory results. None, however, investigated whether inadequate nutrition is due to CF patients having different liking for foods compared to healthy children and whether liking can be linked to specific changes in smell or taste function. Here, the relationships between food liking, BMI, and smell and taste function in 42 CF and 42 healthy 5- to 18-year olds is pursued. A three-choice 16-item odor identification test and a gustatory identification test involving five concentrations of sweet, sour, bitter, and salty tastes, were used to assess chemosensory function. Food liking was assessed using a 94-item questionnaire. Patients identified significantly fewer odors than controls (89.8% vs. 95.7% correct; P < 0.001). However, only a few patients were affected and their loss of olfactory function was not substantial and unlikely to affect their liking for foods. Taste identification was similar for the two groups (patients 92.6% vs. controls 94.2% correct). There was no correlation between age and odor identification ability, but taste performance improved with age (r = 0.39, P < 0.05), suggesting cognition was the cause. Patients liked several types of foods and high-fat foods more than the controls. Both groups had a similar liking for low-fat foods and both liked high-fat foods more than low-fat foods. No significant relationships existed between FEV(1) and smell or taste function or liking for foods, the BMI of the groups were similar and there was no relationship between BMI and smell or taste function. The results indicate that the abnormal eating behavior reported for many CF patients is not due to changes in chemosensory function which remains normal in most CF patients at least to 18 years of age.

Parents' religious coping styles in the first year after their child's cystic fibrosis diagnosis

Parents of children diagnosed with cystic fibrosis described it as "devastating." Given religion's importance to many Americans, parents may utilize religious coping. Relatively little is known about parents' use of religious coping to handle their child's illness. Interviews with 15 parents about their use of religion in the year following their child's cystic fibrosis diagnosis were coded for religious coping styles. Sixteen styles were identified. Positive religious coping styles were more frequent than negative styles (previously associated with poorer health outcomes), and occurred more frequently than in other studies. Religious coping styles used to make meaning, gain control, or seek comfort/intimacy with God were equally prevalent. The most common styles were: Pleading, Collaboration, Benevolent Religious Reappraisals, and Seeking Spiritual Support. Parents described active rather than passive coping styles. Religious coping involving religious others was rare. Clinical attention to negative religious coping may prevent it becoming chronic and negatively affecting health.

Aquaporin 1 water channel is overexpressed in the plasma membranes of pancreatic ducts in patients with autoimmune pancreatitis

Chronic pancreatitis with all kinds of etiologies is characterized by pancreatic exocrine dysfunction especially impaired fluid secretion from pancreatic ducts. However, the molecular mechanism of this impaired fluid secretion in chronic pancreatitis is largely unknown. Aquaporin water channels are intrinsic membrane proteins expressed most of the cell types which have high osmotic water permeability. Among them aquaporin 1 (AQP1) is a predominant water channel expressed in the plasma membranes of human pancreatic ducts. Exocrine function test revealed that fluid secretion was severely impaired in AIP. immunohistochemical analysis revealed that AQP1 is localized mainly in the apical and lateral membranes of small pancreatic ducts in control subjects. AQP1 expression was significantly increased in plasma membranes of pancreatic ducts in AIP. Upregulation of AQP1 expression seen in pancreatic ducts of patient with AIP may be caused by the reduced fluid secretion from the pancreas as compensation. Further study would be required to elucidate the precise molecular mechanism for the role of AQP1 in pancreatic fluid secretion from the pancreas in diseases characterized by the impaired ductal fluid secretion such as cystic fibrosis.

Incorporating genetic potential when evaluating stature in children with cystic fibrosis

OBJECTIVE

The 2002 Cystic Fibrosis Foundation (CFF) practice guidelines recommend adjusting for genetic potential when evaluating height status in children with CF. However, there is paucity of data to support this recommendation. We compared three methods of classifying short stature: unadjusted height percentile <10th, Himes adjusted height percentile <10th, and unadjusted height below the CFF target height lower bound.

PATIENTS AND METHODS

Data from 3306 children with parental heights documented in the 1986-2005 CFF Patient Registry were analyzed.

RESULTS

Mean height percentile of CF children (33rd) was lower than their parents' (mothers' 53rd, fathers' 57th), and 80% of CF children were below the average of their parental height percentiles. In children with short parents, Himes adjusted height percentile was significantly higher than unadjusted height percentile (27th vs. 8th), whereas the opposite was found in children with tall parents (Himes adjusted at 18th vs. unadjusted at 49th). Consequently, the prevalence of short stature decreased from 52% to 22% in children with short parents and increased from 8% to 34% in children with tall parents after Himes adjustment. In children with discrepant classification on short stature before and after Himes adjustment, percent predicted forced expiratory volume in one second was negatively associated with unadjusted height percentile but positively associated with Himes adjusted height percentile. In children with short parents, the CFF method underestimated the prevalence of short stature (9%) compared to the Himes method (22%).

CONCLUSION

Without adjustment of genetic potential, the prevalence of short stature is underestimated and the association between height and lung function is biased.

Improving the quality of care for patients with cystic fibrosis

PURPOSE OF REVIEW

Improvement in cystic fibrosis (CF) outcomes over the past 50 years has been dramatic. This article describes the factors that have contributed to the recent acceleration in this improvement and the important role of the Cystic Fibrosis Foundation.

RECENT FINDINGS

Initiatives to improve CF care over the past decade include the refinement of a sophisticated patient registry that allows a comparison of center processes and outcomes; development of evidence-based and consensus-based guidelines regarding standards of care; cultural transformation, including the training of care center teams in a systems-oriented approach to quality improvement; data transparency; and encouragement of a patient-centered and family-centered orientation. Cystic Fibrosis Foundation initiatives have promoted an increase in the consistent provision of evidence-based care and the promulgation of innovative, proactive therapeutic approaches. Unfortunately, so far most of these accomplishments have not been documented in peer-reviewed research articles, but rather in platform presentations at national meetings, meeting abstracts, data reports to center directors, and published reports from individual centers.

SUMMARY

While several new medications for CF lung disease have been introduced in the last decade, improvements in outcomes have been largely due to refinements in the delivery of care. At this point, the most efficient and reliably effective technique for promoting further improvement still needs to be identified. Recent discussions have centered on attempts at new innovative approaches that utilize more selective teaching of relevant systems-based quality improvement methods in the specific CF environment.

Efficacy and tolerability of a new formulation of pancrelipase delayed-release capsules in children aged 7 to 11 years with exocrine pancreatic insufficiency and cystic fibrosis: a multicenter, randomized, double-blind, placebo-controlled, two-period crossover, superiority study

BACKGROUND

Pancreatic enzyme replacement therapy (PERT) is essential for maintaining adequate nutrition in children with exocrine pancreatic insufficiency (EPI) due to cystic fibrosis (CF). The US Food and Drug Administration regulations now require all PERT products to undergo clinical efficacy and safety studies before they can be considered for marketing approval.

OBJECTIVE

This study was conducted to compare the efficacy of a new formulation of pancrelipase (pancreatin) delayed-release 12,000-lipase unit capsules with placebo in children with EPI due to CF.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled, 2-period crossover, superiority study of the new formulation of pancrelipase delayed-release 12,000-lipase unit capsules in children aged 7 to 11 years with CF and EPI. In each period, pancrelipase or identical placebo capsules were taken for 5 days. The primary outcome measure was the coefficient of fat absorption (CFA); secondary outcome measures were the coefficient of nitrogen absorption (CNA) and clinical symptoms. The latter were assessed based on patient-reported daily stool frequency, stool consistency (hard, formed/normal, soft, or watery), flatulence (none, mild, moderate, or severe), and abdominal pain (none, mild, moderate, or severe). Safety measures included vital signs, physical examinations, standard laboratory safety tests (hematology and biochemistry), and adverse events.

RESULTS

Seventeen patients were randomized to treatment and 16 completed the study; 1 patient withdrew consent during the first treatment period and was not included in the efficacy analysis. Patients' median age was 8.0 years (range, 7-11 years); 12 patients (70.6%) were male. CFA values were significantly greater for pancrelipase compared with placebo, with least squares mean (SE) values of 82.8% (2.7%) and 47.4% (2.7%), respectively (P < 0.001). The results were similar for CNA, with mean values of 80.3% (3.2%) and 45.0% (3.2%) (P < 0.001). Pancrelipase treatment had significantly greater effects on CFA and CNA in patients with a placebo CFA <50% than in those with a placebo CFA >50% (both parameters, P < 0.001 and P = 0.008, respectively). Significant improvements in stool fat, weight, and nitrogen and a significant reduction in daily stool frequency were observed with pancrelipase compared with placebo (all, P < 0.001). Symptoms of EPI were less severe and remained relatively stable during pancrelipase treatment, but worsened slightly during receipt of placebo. Treatment-emergent adverse events were reported in 5 patients (29.4%) during receipt of pancrelipase and in 9 patients (56.3%) during receipt of placebo; these were predominantly gastrointestinal events. There were no discontinuations due to treatment-emergent adverse events and no serious adverse events.

CONCLUSIONS

In this study in children with EPI due to CF, the new formulation of pancrelipase delayedrelease capsules was associated with improvements in CFA, CNA, stool properties, and EPI symptoms compared with placebo. Pancrelipase delayed-release capsules appeared to be well tolerated. ClinicalTrials.gov identifier: NCT00690820. (Clin Ther.

Developmental and psychosocial issues in CF

Cystic fibrosis (CF) is a multisystemic life-limiting genetic disorder, primarily affecting respiratory functioning. Most patients with CF are diagnosed by 2 years of age, and the current median predicted survival rate is 37.4 years old, with 95% of patients dying from complications related to pulmonary infection. Given the chronic, progressive, and disabling nature of CF, multiple treatments are prescribed, most on a daily basis. Thus, this illness requires children, with the aid of their families, to adopt multiple health-related behaviors in addition to managing more typical developmental demands. The morbidity and mortality factors pose cognitive, emotional, and behavioral challenges for many children with CF and their families. This article applies a developmental perspective to describing the psychosocial factors affecting psychological adjustment and health-related behaviors relevant to infants, preschool and school-age children, and adolescents with CF. Topics particularly pertinent to developmental periods and medical milestones are noted, with clinical implications highlighted.

Nutritional considerations in patients with cystic fibrosis

Nutritional status is strongly associated with pulmonary function and survival in cystic fibrosis patients. Attainment of a normal growth pattern in childhood and maintenance of adequate nutritional status in adulthood represent major goals of multidisciplinary cystic fibrosis centers. International guidelines on energy intake requirements, pancreatic enzyme-replacement therapy and fat-soluble vitamin supplementation are of utmost importance in daily practice. The present review summarizes the most up-to-date information on early nutritional management in newly diagnosed patients and evaluates the benefits of aggressive nutritional support, assessment of nutritional status, recommendations for nutrition-related management in pancreatic-insufficient patients and the possible therapeutic impact of fat intake modulation upon inflammatory status.

Oxandrolone Improves Height Velocity and BMI in Patients with Cystic Fibrosis

Objective. To evaluate the effectiveness of oxandrolone in improving the nutritional status and linear growth of pediatric patients with cystic fibrosis (CF). Methods. Medical records of patients with CF treated with oxandrolone were reviewed for height z score, height velocity (HV), BMI z score, weight velocity (WV), Tanner stage, pulmonary function, liver enzyme levels, and any reported adverse events. Data were compared before (pre-Ox) and after (Ox) oxandrolone using a paired t-test. Results. 5 subjects (ages 8.5–14.5 years) were treated with oxandrolone 2.5 mg daily for 8–38 months. After 8–12 months of treatment, there was a statistically significant improvement in HV (pre-Ox = 5.3 ± 1.4 cm/yr, Ox = 8.3 ± 1.2 cm/yr, P < .01) and BMI z score (pre-Ox = −0.61 ± 1.04, Ox = −0.30 ± 0.86, P = .02). Both height z score (pre-Ox = −1.64 ± 0.63, Ox = −1.30 ± 0.49, P = .057) and WV (pre-Ox = 4.2 ± 3.7 kg/yr, Ox = 6.8 ± 1.0 kg/yr, P = .072) showed beneficial trends that did not reach statistical significance. No adverse events were reported. Conclusions. In this brief clinical report, oxandrolone improved the HV and BMI z score in patients with CF. Larger studies are needed to determine if oxandrolone is an effective, safe, and affordable option to stimulate appetite, improve weight gain, and promote linear growth in patients with CF.

Risk factors associated with depressive symptoms in caregivers of children with type 1 diabetes or cystic fibrosis

OBJECTIVE

Evaluate depressive symptoms in caregivers of children with type 1 diabetes (T1D) or cystic fibrosis (CF) and identify associated risk factors.

METHODS

A total of 195 caregivers completed demographic, stress, and depressive symptoms questionnaires. Children's health status was obtained from medical records.

RESULTS

Approximately 33% of caregivers reported elevated symptoms of depression (i.e., exceeded clinical cutoff of 16 on the Center for Epidemiological Studies-Depression Scale). For caregivers of children with T1D, elevations were associated with less caregiver education, more family stress, older child age, and worse glycemic control. For caregivers of children with CF, more family stress and lack of employment outside of the home were associated with elevated depressive symptoms.

CONCLUSIONS

Many caregivers of children with T1D or CF experience depressive symptoms, although risk factors may differ in these two populations. Screening of caregiver depressive symptoms as part of routine clinic visits may provide opportunities for needed intervention.

Mealtime problems predict outcome in clinical trial to improve nutrition in children with CF

Better growth and nutritional status is strongly associated with better pulmonary function and survival in children with CF. Behavioral intervention is an efficacious treatment approach for improving calorie intake and weight gain in children with CF; and recently has been shown to facilitate maintenance of daily energy intake at 120% of the healthy population over a 2-year period. However, no study to date has examined factors that predict outcome with behavior intervention to promote weight gain in CF. The objectives of this study were to examine the influence of nutritional status, mealtime behavior problems, and maternal depressive symptoms on calorie intake and weight gain following participation in a randomized trial to improve nutritional status in cystic fibrosis. Sixty-seven children, aged 4-12 years with cystic fibrosis participated in a clinical trial targeting calorie and weight increases. Participants completed baseline measures of mealtime behavior problems, maternal depression, and fat absorption, and baseline and post-treatment caloric intake and weight. Assignment to behavioral group (R(2) change = 0.17), lower frequency of mealtime behavior problems (R(2) change = 0.11), and higher maternal depression (R(2) change = 0.06) predicted greater calorie increase baseline to post-treatment. Assignment to behavioral group (R(2) change = 0.09), higher baseline weight (R(2) change = 0.10), fat absorption (R(2) change = 0.02), and lower frequency of mealtime behavior problems (R(2) change = 0.06) predicted greater weight gain baseline to post-treatment. Less frequent mealtime behavior problems led to better calorie intake and weight gain in a 9-week clinical trial of behavior intervention and nutrition education to improve nutritional status in cystic fibrosis. The key implication from these findings is that early referral to behavioral intervention as soon as growth deficits become a concern will likely yield the best nutritional outcomes.

Nutrition Knowledge and Confidence Levels of Parents of Children With Cystic Fibrosis

Optimal growth and nutrition status predict better lung function and longevity for children with cystic fibrosis (CF). Daily nutrition therapy for children with CF requires adequate food resources, parental knowledge of nutrition and behavior management, and confidence in one’s ability to apply the skills. The Mountain West Cystic Fibrosis Consortium Questionnaire (MWCFC-Q) was designed to identify educational intervention targets to improve the growth and nutrition of children with CF. Parents of children with CF returned 305 anonymous MWCFC-Qs. Data analyzed included household food security, knowledge of nutrition and general CF therapies, and self-confidence in one’s ability to manage components of CF care. Factors associated with food insecurity were reported by 26.3% of respondents. The median accuracy for questions regarding nutrient content of commonly used foods was 71.4% and 57.9% for CF nutrition therapy. Parents’ self-confidence in overall CF management was relatively high at a mean value 8.28 ± 1.22 of 10 possible. However, mean self-confidence in the CF nutrition domain was significantly less than mean self-confidence for the CF-related tasks domain, which included chest physiotherapy and medication administration (7.75 ± 1.56, 8.62 ± 1.24, P < .001, respectively). Parental knowledge of nutrition for CF and confidence in the application of this knowledge can improve the growth and nutrition status of children with CF. Identification of food security issues may enable health care professionals to adjust nutrition interventions and direct families to appropriate food resources. The MWCFC-Q could be useful for designing and testing educational interventions for nutrition management of CF.

Diagnosing exocrine pancreatic insufficiency after surgery: when and which patients to treat

Exocrine pancreatic insufficiency (EPI) is a common problem after surgery of the pancreas and stomach. It is usually caused by inadequate pancreatic enzyme activity resulting from insufficient enzyme production, insufficient enzyme activation or disturbed enzyme deactivation. A variety of direct and indirect pancreatic function tests such as the secretin-cerulein test, the faecal elastase test and the (13)C-mixed triglyceride breath test are used to assess exocrine pancreatic function. Few studies have addressed pancreatic enzyme replacement therapy (PERT) following pancreatic surgery. These studies suggest beneficial effects of enzyme replacement after pancreatic resections. A number of studies have been performed to assess post-gastrectomy maldigestion and PERT. The treatment options remain controversial, although the published evidence is in favour of PERT leading to an overall improvement of symptoms. In conclusion, EPI following pancreatic surgery and total or partial gastrectomy remains a common clinical challenge. As a result of the lack of solid evidence, more clinical trials, particularly randomized, controlled clinical trials, are urgently needed.

Evaluation of the upper airway in children and adolescents with cystic fibrosis and obstructive sleep apnea syndrome

OBJECTIVE

Obstructive sleep apnea syndrome (OSAS) in cystic fibrosis (CF) patients may be associated with the presence of upper airway obstruction caused by chronic infection and nasal polyposis that may also contribute to OSAS severity. Our objective was to identify the profile of findings in CF and OSAS patients by performing upper airway examinations.

METHODOLOGY

Observational, cross-sectional study involving 63 children and adolescents between the ages of 2 and 14 with CF. All patients answered a questionnaire and underwent a standard otolaryngology examination, including an endoscopic nasal and nocturnal polysomnography. OSAS diagnosis was confirmed if the obstructive apnea index was >or=1.

RESULTS

OSAS was identified in 35 (55.6%) patients. The upper airway findings were evaluated using multiple correspondence factorial analysis. The OSAS group presented with overjet >2mm, enlarged pharyngeal pillars, palatine tonsils and pharyngeal tonsils hypertrophy, ogival hard palates and characteristics of chronic rhinosinusitis.

CONCLUSION

Bone and soft tissue structural alterations of the upper airway and chronic rhinosinusitis were associated with the OSAS group patients.

Cystic Fibrosis Foundation evidence-based guidelines for management of infants with cystic fibrosis

Newborn screening for cystic fibrosis (CF) offers the opportunity for early medical and nutritional intervention that can lead to improved outcomes. Management of the asymptomatic infant diagnosed with CF through newborn screening, prenatal diagnosis, or sibling screening is different from treatment of the symptomatically diagnosed individual. The focus of management is on maintaining health by preventing nutritional and respiratory complications. The CF Foundation convened a committee to develop recommendations based on a systematic review of the evidence and expert opinion. These guidelines encompass monitoring and treatment recommendations for infants diagnosed with CF and are intended to help guide families, primary care providers, and specialty care centers in the care of infants with CF.

Management of infants with cystic fibrosis: a summary of the evidence for the cystic fibrosis foundation working group on care of infants with cystic fibrosis

OBJECTIVE

To inform the development of Cystic Fibrosis (CF) Foundation guidelines on the care of infants with CF, we systematically reviewed the evidence for diagnosis and assessment of pancreatic and pulmonary disorders; management of pancreatic and pulmonary function; management of nutrition and nutritional disorders; and prevention and control of infections.

STUDY DESIGN

In May-June 2008, we searched The Cochrane Library for existing reviews; and MEDLINE, the National Guideline Clearinghouse, the CF Foundation Clinical Practice Guidelines and Consensus Statements, and the UK CF Trust for existing guidelines. MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and the Excerpta Medica Database (EMBASE) were searched for primary studies in January 2008. Bibliographies of eligible articles were searched and expert input was sought. We selected English-language articles of any study design that provided original data on any of our questions on infants up to 2 years of age.

RESULTS

We identified 14 relevant guidelines and 3 Cochrane reviews. Fifty-nine articles (55 primary studies) were included. Only four of these were randomized controlled trials. Sample sizes of infants ranged from 2 to 768 study participants; the median sample size was 24. Of our 21 review topics, 5 topics had only one study while for 5 we identified no relevant studies. We identified one or no primary studies for 20 of 32 review questions.

CONCLUSIONS

There is a paucity of evidence on the care of infants diagnosed with CF. For several of the review questions no guidelines or primary studies were identified, but for other questions, studies limited by weak design and small sample sizes were the only studies identified. With increasing numbers of infants with CF being diagnosed by newborn screening there is an opportunity to study the management of infants diagnosed with CF.

The recognition and treatment of growth disorders - a 50-year retrospective

The past 50 years have seen great progress in the understanding and treatment of classic growth disorders. Advances such as the recognition of hormone receptor defects, the development of recombinant growth hormone, and the expanding awareness of epigenetic phenomena affecting growth are among these great achievements. Yet growth failure remains a pervasive problem among children with complex health conditions, such as survivors of childhood cancers, premature infants, organ transplant recipients, and children with cystic fibrosis. The significant increases in life expectancy among these groups underscores the potential consequences of poor growth, whether due to the underlying conditions or medical treatments, as they may have long-lasting effects into adulthood. The ongoing contributions of human biologists to the study of human growth remain essential in the recognition and treatment of growth disorders, by defining normal patterns of growth and body composition, the interplay of growth and maturation, the role of environmental, behavioral and genetic factors, and the long-term consequences of growth patterns. Examples will be given based on two common genetic disorders, cystic fibrosis and sickle-cell anemia, to highlight the relationships between growth failure, survival, and malnutrition. Also, a study of bone mineral accretion in children with cystic fibrosis will illustrate the importance of understanding patterns of growth in healthy children, and their application in the diagnosis and management of children with chronic disease. These examples accentuate the need for continued participation of human biologists in the study of growth and development and the care of children.

Randomized clinical trial of behavioral intervention and nutrition education to improve caloric intake and weight in children with cystic fibrosis

OBJECTIVE

To evaluate the efficacy of a behavioral plus nutrition education intervention, Be In CHARGE!, compared with that of a nutrition education intervention alone on caloric intake and weight gain in children with cystic fibrosis and pancreatic insufficiency.

DESIGN

Randomized controlled trial.

SETTING

Cystic fibrosis centers in the eastern, midwestern, and southern United States.

PARTICIPANTS

Seventy-nine children aged 4 to 12 years below the 40th percentile for weight for age were recruited. Sixty-seven completed the intervention and 59 completed a 24-month follow-up assessment.

INTERVENTION

Comparison of a behavioral plus nutrition education intervention with a nutrition education intervention alone.

MAIN OUTCOME MEASURES

Primary outcomes were changes from pretreatment to posttreatment in caloric intake and weight gain. Secondary outcomes were changes from pretreatment to posttreatment in percentage of the estimated energy requirement and body mass index z score. These outcomes were also examined 24 months posttreatment.

RESULTS

After treatment, the behavioral plus nutrition education intervention as compared with the nutrition education intervention alone had a statistically greater average increase on the primary and secondary outcomes of caloric intake (mean, 872 vs 489 cal/d, respectively), percentage of the estimated energy requirement (mean, 148% vs 127%, respectively), weight gain (mean, 1.47 vs 0.92 kg, respectively), and body mass index z score (0.38 vs 0.18, respectively). At the 24-month follow-up, children in both conditions maintained an estimated energy requirement of around 120% and did not significantly differ on any outcomes.

CONCLUSIONS

A behavioral plus nutrition education intervention was more effective than a nutrition education intervention alone at increasing dietary intake and weight over a 9-week period. However, across the 24-month follow-up, both treatments achieved similar outcomes. Trial Registration clinicaltrials.gov Identifier: NCT00006169.

Efficacy and safety of Creon 24,000 in subjects with exocrine pancreatic insufficiency due to cystic fibrosis

BACKGROUND

Pancreatic enzyme replacement therapy is critical for adequate nutrition in cystic fibrosis (CF) patients with exocrine pancreatic insufficiency (EPI).

METHODS

This was a double-blind, randomised, placebo-controlled, two-period crossover study assessing efficacy and safety of Creon 24,000-unit capsules in CF subjects > or =12 years with EPI. Patients were randomised to one of two 5-day sequences, Creon/placebo or placebo/Creon (target dose, 4000 lipase units/g fat). Primary outcome was the coefficient of fat absorption (CFA); secondary outcomes were coefficient of nitrogen absorption (CNA), symptoms, and safety.

RESULTS

Thirty-two subjects were randomised. Mean CFA and CNA were significantly greater with Creon than placebo (CFA, 88.6% vs. 49.6%; CNA, 85.1% vs. 49.9%; p<0.001 for both). Symptoms were improved and fewer treatment-emergent adverse events were reported with Creon than placebo. One patient discontinued for weight loss unrelated to study drug.

CONCLUSIONS

This study demonstrated Creon was effective in treating EPI due to CF and was safe and well tolerated.

Nutrition management of pediatric patients who have cystic fibrosis

Since the identification of cystic fibrosis (CF) in the 1940s, nutrition care of patients who have CF has been a challenge. Through optimal caloric intake and careful management of malabsorption, patients are expected to meet genetic potential for growth. Yet factors beyond malabsorption, including nutrient activity at the cellular level, may influence growth and health. This article reviews nutrition topics frequently discussed in relationship to CF and presents intriguing new information describing nutrients currently being studied for their impact on overall health of patients who have CF.

Growth assessment of paediatric patients with CF comparing different auxologic indicators: A multicentre Italian study

OBJECTIVES

To evaluate growth in Italian patients with cystic fibrosis (CF).

PATIENTS AND METHODS

A multicentre cross-sectional study was carried out on patients with CF attending Italian reference centres. Anthropometric data were evaluated using the Centers for Disease Control and Prevention 2000 reference data. Nutritional failure was defined as height-for-age percentile (HAP) <5th (all patients); weight-for-length percentile (WLP) <10th (patients <2 years); body mass index percentile (BMIp) <15th (patients between 2 and 18 years). The risk of malnutrition (defined as HAP, WLP, and BMIp <25th) and the proportion of patients below the "BMIp goal" (BMIp > or =50th) were also evaluated. Nutritional status was evaluated in the whole population and in relation to age, sex, pancreatic insufficiency, meconium ileus, and lung function.

RESULTS

A total of 892 patients with CF (50.7% males, mean age 9.2 years, range 0.1-18 years) were enrolled. The proportion of children with HAP <5th, WLP<10th and BMIp<15th was 12.2%. 12.9%, 20.9%, respectively, and 54.4% did not fulfill the BMIp > or =50th goal. HAP <25th identified the highest proportion of children at risk of malnutrition, whereas BMIp <15th identified the highest proportion of children with nutritional failure. Whatever the criterion used to define malnutrition, the highest proportion of children with nutritional failure was found in adolescence (11-18 years). z scores for height, weight, and BMI were significantly associated with pancreatic status and lung function. Differences among centres for the auxologic parameters were not significant, except for BMIp.

CONCLUSIONS

Nutritional failure is present in a minority of Italian patients with CF, particularly during adolescence. Different auxologic indicators should be used for identifying children at risk for or with actual malnutrition.

Symposium 6: Young people, artificial nutrition and transitional care The nutritional challenges of the young adult with cystic fibrosis: transition

Cystic fibrosis (CF) is a complex multisystem disorder affecting mainly the gastrointestinal tract and respiratory system. Intestinal malabsorption occurs in approximately 90% of patients. In the past, malnutrition was an inevitable consequence of disease progression, leading to poor growth, impaired respiratory muscle function, decreased exercise tolerance and immunological impairment. A positive association between body weight and height and survival has been widely reported. The energy requirements of patients with CF vary widely and generally increase with age and disease severity. For many young adults requirements will be 120–150% of the age-related estimated average requirement. To meet these energy needs patients are encouraged to eat a high-fat high-energy diet with appropriate pancreatic enzyme supplements. Many patients are unable to achieve an adequate intake as a result of a variety of factors including chronic poor appetite, infection-related anorexia, gastro-oesophageal reflux and abdominal pain. Oral energy supplements and enteral tube feeding are widely used. Nutritional support has been shown to improve nutritional status and stabilise or slow the rate of decline in lung function. With such emphasis on nutritional intake and nutritional status throughout life, poor adherence to therapies and issues relating to body image are emerging. The median survival of patients with CF is increasing. CF is now considered a life-limiting disease of adulthood rather than a terminal childhood illness. With increased longevity new challenges are emerging that include the transition of young adults with CF to adult services, CF-related diabetes, disordered eating, osteoporosis, liver disease and transplantation.

Description of a standardized nutrition classification plan and its relation to nutritional outcomes in children with cystic fibrosis

OBJECTIVE

Better nutrition enhances lung function and increases survival for children with cystic fibrosis (CF). Therefore, we developed a standardized strategy to evaluate nutritional status and create individualized treatment plans to ensure that all patients received the same high-quality care in a busy CF Center.

METHODS

A quality improvement approach was undertaken to develop a novel nutrition classification strategy to identify and treat children with subtle manifestations of nutritional deficits in addition to those with obvious nutritional issues.

RESULTS

During the 15-month study period, the median body mass index (BMI) percentile increased from 35.2 (0-95.9) to 42.0 (0-97.7), p < .005. Additionally, the number of children with a BMI >or=50th percentile increased by 11.8%.

CONCLUSIONS

Adoption of a standardized approach to nutritional assessment and treatment led to significant improvement in nutritional outcomes of CF patients, demonstrating that systematic changes in clinical practice can improve clinical outcomes substantially over a short period of time.

Dichotomy between postprandial glucose and lipid profiles in adults with cystic fibrosis: a pilot study

BACKGROUND

Cystic fibrosis (CF) patients present a high incidence of glucose tolerance abnormalities. Altered insulin secretion combined with recommended high-fat intake could be associated with dysregulation of glucose and lipid metabolism. We examined postprandial glucose and lipid profiles during an oral glucose tolerance test (OGTT) and following a standardized high-fat test meal (TM).

METHODS

Sixteen CF patients with normal glucose tolerance (NGT) or CF-related diabetes (CFRD) and 16 controls underwent a 4 h OGTT and a TM. We then measured plasma glucose, insulin, free fatty acid (FFA) and triglyceride (TG) concentrations.

RESULTS

CF patients presented higher glucose excursion compared to controls after the OGTT and TM. However, in CF patients, this excursion was significantly reduced in both amplitude and length after the TM. The TM provoked a comparable increase in TG levels in both groups whereas they remained stable during the OGTT. FFAs were suppressed similarly in both groups after both challenges.

CONCLUSION

CF is associated with abnormal glucose excursion in the presence of relatively normal lipid excursion. The rapid normalization of glucose values after a mixed meal should be further explored and, if confirmed, might have significant implications for CFRD diagnostic.

Classification of malnutrition in cystic fibrosis: implications for evaluating and benchmarking clinical practice performance

BACKGROUND

In 2005, the Cystic Fibrosis Foundation (CFF) revised the nutrition classification guidelines to eliminate the use of percentage of ideal body weight (%IBW) to define "nutritional failure"; the CFF also recommended that children with cystic fibrosis maintain a body mass index percentile (BMIp) > or = 50th.

OBJECTIVE

We assessed the effect of the 2005 CFF nutrition classification guidelines on evaluating the performance of nutritional care practices.

DESIGN

Data from 14,702 children reported to the 2002 CFF Patient Registry were analyzed to compare malnutrition rates in 113 cystic fibrosis centers in the United States. Nutritional failure was defined according to the 2002 CFF criteria--ie, height < 5th percentile, %IBW < 90%, or BMIp < 10th. "Below BMI goal" was defined according to the 2005 CFF criterion, ie BMIp < 50th.

RESULTS

Eliminating %IBW resulted in a 6% reduction (from 33% to 27%) in the nutritional failure rate in the United States. The use of BMIp < 50th led to the classification of 57% of children as below the BMI goal. Misclassification of nutritional failure according to %IBW ranged from 1% to 16% among 113 centers and was greater in the centers with a larger proportion of tall patients. After the elimination of %IBW, one-third of centers changed to a different tertile ranking for nutritional failure rates (kappa = 0.50, moderate-to-poor agreement). More than half the centers changed to a different tertile ranking, from nutritional failure to below BMI goal (kappa = 0.22, poor agreement).

CONCLUSION

Eliminating misclassification by %IBW and implementing the new BMI goal led to profound and unequal changes in malnutrition rates across cystic fibrosis centers.