Short-term clinical, nutritional, and functional effects of continuous elemental enteral alimentation in children with cystic fibrosis

Nutritional Care in Children with Cystic Fibrosis

Patients with cystic fibrosis (CF) are prone to malnutrition and growth failure, mostly due to malabsorption caused by the derangement in the chloride transport across epithelial surfaces. Thus, optimal nutritional care and support should be an integral part of the management of the disease, with the aim of ameliorating clinical outcomes and life expectancy. In this report, we analyzed the nutrition support across the different ages, in patients with CF, with a focus on the relationships with growth, nutritional status, disease outcomes and the use of the CF transmembrane conductance regulator (CFTR) modulators. The nutrition support goal in CF care should begin as early as possible after diagnosis and include the achievement of an optimal nutritional status to support the growth stages and puberty development in children, that will further support the maintenance of an optimal nutritional status in adult life. The cornerstone of nutrition in patients with CF is a high calorie, high-fat diet, in conjunction with a better control of malabsorption due to pancreatic enzyme replacement therapy, and attention to the adequate supplementation of fat-soluble vitamins. When the oral caloric intake is not enough for reaching the anthropometric nutritional goals, supplemental enteral feeding should be initiated to improve growth and the nutritional status. In the last decade, the therapeutic possibilities towards CF have grown in a consistent way. The positive effects of CFTR modulators on nutritional status mainly consist in the improvement in weight gain and BMI, both in children and adults, and in an amelioration in terms of the pulmonary function and reduction of exacerbations. Several challenges need to be overcome with the development of new drugs, to transform CF from a fatal disease to a treatable chronic disease with specialized multidisciplinary care.

Brazilian Guidelines for Nutrition in Cystic Fibrosis

OBJECTIVE

To develop a scientific consensus on nutrition in cystic fibrosis.

METHODS

Sixteen coordinators elaborated relevant questions on nutritional therapy in cystic fibrosis, which were divided into six sections: nutritional assessment, nutritional recommendations, nutritional intervention, dietary counseling, special situations and enzyme replacement, and gastrointestinal manifestations. Two to three specialists in the field were responsible for each section and obtaining answers formulated based on standardized bibliographic searches. The available literature was searched in the PubMed®/MEDLINE database, after training and standardization of search strategies, to write the best level of evidence for the questions elaborated. Issues related to disagreement were discussed until a consensus was reached among specialists, based on the current scientific literature.

RESULTS

Forty-two questions were prepared and objectively answered, resulting in a consensus of nutritional therapy in cystic fibrosis.

CONCLUSION

This work enabled establishing a scientific consensus for nutritional treatment of cystic fibrosis patients.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when oral dietary and supplement intake has failed to achieve an adequate nutritional status. The use of this method of feeding is assessed on an individual basis taking into consideration the patients age and clinical status. This is a final update of a previously published review.

OBJECTIVES

To examine the evidence that in people with cystic fibrosis, supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also contacted the companies that market enteral feeds and reviewed their databases.Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 10 July 2019.Date of the most recent hand search of PubMed: 26 October 2018.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

The searches identified 44 trials; however, none were eligible for inclusion in this review.

MAIN RESULTS

There are no trials included in this review.

AUTHORS' CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are expensive and may have a negative effect on self-esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement; but, efficacy has not been fully assessed by randomised controlled trials. It is acknowledged, however, that performing a randomised controlled trial would be difficult due to the ethics of withholding an intervention in a group of people whose nutritional status necessitates it.

Enteral tube feeding for individuals with cystic fibrosis: Cystic Fibrosis Foundation evidence-informed guidelines

Nutrition is integral to the care of individuals with cystic fibrosis (CF). Better nutritional status is associated with improved pulmonary function. In some individuals with CF, enteral tube feeding can be useful in achieving optimal nutritional status. Current nutrition guidelines do not include detailed recommendations for enteral tube feeding. The Cystic Fibrosis Foundation convened an expert panel to develop enteral tube feeding recommendations based on a systematic review of the evidence and expert opinion. These guidelines address when to consider enteral tube feeding, assessment of confounding causes of poor nutrition in CF, preparation of the patient for placement of the enteral feeding tube, management of the tube after placement and education about enteral feeding. These recommendations are intended to guide the CF care team, individuals with CF, and their families through the enteral tube feeding process.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when oral dietary and supplement intake has failed to achieve an adequate nutritional status. The use of this method of feeding is assessed on an individual basis taking into consideration the patients age and clinical status.

OBJECTIVES

To examine the evidence that in people with cystic fibrosis, supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also contacted the companies that market enteral feeds and reviewed their databases.Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 13 February 2015.Date of the most recent hand search of PubMed and conference abstract books: 13 February 2015.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

The searches identified 38 trials; however, none were eligible for inclusion in this review.

MAIN RESULTS

There are no trials included in this review.

AUTHORS' CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are expensive and may have a negative effect on self-esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement; but, efficacy has not been fully assessed by randomised controlled trials. It is acknowledged, however, that performing a randomised controlled trial would be difficult due to the ethics of withholding an intervention in a group of patients whose nutritional status necessitates it.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when oral dietary and supplement intake has failed to achieve an adequate nutritional status. The use of this method of feeding is assessed on an individual basis taking into consideration the patients age and clinical status.

OBJECTIVES

To examine the evidence that in people with cystic fibrosis, supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also contacted the companies that market enteral feeds and reviewed their databases.Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 03 September 2012.Date of the most recent hand search of PubMed and conference abstract books: 15 June 2012.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Thirty-one trials were identified by the searches; however, none were eligible for inclusion in this review.

MAIN RESULTS

There are no trials included in this review.

AUTHORS' CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are expensive and may have a negative effect on self-esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement; but, efficacy has not been fully assessed by randomised controlled trials. It is acknowledged, however, that performing a randomised controlled trial would be difficult due to the ethics of withholding an intervention in a group of patients whose nutritional status necessitates it.

Successful prolonged use of recombinant human insulin-like growth factor-1 in a child with cystic fibrosis

Growth failure is a common and complicated process in children with cystic fibrosis (CF). Growth hormone, which is becoming a more commonly used agent in such patients, has demonstrated beneficial effects aside from increased growth velocity. Recently, insulin-like growth factor-1 has gained significant attention in the understanding of growth failure in children with CF. We report the successful prolonged use of recombinant human insulin-like growth factor-1 in an adolescent boy with CF, who demonstrated significant clinical benefits from the therapy.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when weight for height percentage is less than 85%, when there has been weight loss for longer than a two-month period or when there has been no weight gain for two to three months (under five years old) or for six months (over five years old).

OBJECTIVES

To examine the evidence that in people with cystic fibrosis supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH STRATEGY

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also contacted the companies that market enteral feeds and reviewed their databases. Date of the most recent search of the Group's Cystic Fibrosis Trials Register: November 2007.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Thirteen trials were identified by the search; however, none were eligible for inclusion in this review.

MAIN RESULTS

There are no trials included in this review.

AUTHORS' CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are invasive, expensive, and may have a negative effect on self-esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement and it is disappointing that their efficacy has not been fully assessed by randomised controlled trials. With the more frequent recommendations to use enteral tube feeding as an early rather than a late intervention, this systematic review identifies the need for a multicentre, randomised controlled trial assessing both efficacy and possible adverse effects of enteral tube feeding in cystic fibrosis. There are no trials included in the review and we have not identified any relevant trials up to November 2007. We therefore do not plan to update this review until new trials are published.

Evaluation of arm anthropometry for assessing pediatric body composition: evidence from healthy and sick children

Arm anthropometry is used as a proxy of body composition in clinical and field research but its validity has not been established in children. To address this issue, mid-upper arm circumference (MUAC) and triceps skinfold thickness (TS) were measured in 110 healthy children aged 4.4-13.9 y (55 boys) and 49 cystic fibrosis (CF) patients aged 8.1-13.4 y (22 boys). Reference values were arm and whole-body fat mass (FM) and fat-free mass (FFM) measured by dual x-ray absorptiometry and four-component model, respectively. Arm fat area (AFA), MUAC, and TS correlated well with arm FM (r = 0.84-0.92) and total FM (r = 0.78-0.92). Arm muscle area (AMA) and MUAC correlated well with arm FFM (r = 0.68-0.82) and total FFM (r = 0.60-0.86). After adjusting for age, sex, and height, arm anthropometry correlated strongly with FM but weakly with FFM. AFA, MUAC, and TS explained 67, 63, and 61% of variability in total FM in healthy children and 70, 72, and 63% in CF. AMA and MUAC explained only 24 and 16% of variability in total FFM in healthy children and 33 and 28% in CF. Arm anthropometry is useful for predicting FM and ranking healthy children and patients for fatness. It has poorer success in predicting regional or total FFM.

Pathogenesis of malnutrition in cystic fibrosis, and its treatment

PATHOGENESIS

We have developed a model of the pathogenesis of malnutrition in cystic fibrosis. It consists of the relationship between nutrient balance and nutrient requirement. The validation has been conducted with respect to energy, but the same general principals can be applied to any nutrient. A patient with CF either loses weight or fails to grow normally if their absorbed energy intake is less than their total daily energy expenditure. Multiple factors have the potential to contribute to reduced energy intake including, anorexia, gastroeosophageal (GE) reflux leading to vomiting and hence food loss, as well as maldigestion. Another more recently recognized source of energy loss, is glucosuria as a result of CF related diabetes (CFRD). Conversely, lung inflammation appears to be related to increases in resting metabolic rate (RMR). Acute exacerbations of the chronic lung disease increases RMR which returns to a basal level some weeks after the inflammation is treated. In clinically stable patients with CF, RMR rises in a quadratic fashion as lung function falls. When FEV(1)is >85% predicted RMR is not different from controls, but it rises in a curvilinear fashion as FEV(1)falls. Initially it appears that patients adapt to their increased RMR by reducing their activity so their total daily energy expenditure (TDEE) is often no higher than controls. But this is by no means always the case. Furthermore good lung care requires CF patients to be involved in aerobic activities, hence their TDEE would rise. Although there has been considerable interest as to whether the genetic defect has an energy wasting effect, it appears genetic factors have little or no effect on RMR.

TREATMENT

This starts with making an energy diagnosis. First, a 3 day faecal fat balance study is conducted. This provides information with regard to intake as well as to maldigestion. In addition a history of GE reflux is sought, since it can readily be treated with H(2)-blockers. If significant fat malabsorption exists, efforts are made to improve pancreatic enzyme dose and function. The possibility of CFRD also needs to be considered. We measure the RMR of the patient using open circuit indirect calorimetry. Recommendations for diet therapy are based on estimated TDEE, which is determined from RMR taking into account faecal losses. Diet therapy places the emphasis on increasing the fat content of the diet. We have conducted a study to determine whether or not oral supplements help increase TDEE and they did not; they merely replaced food energy. Conversely, nocturnal gastrostomy supplemental feeding, while reducing voluntary food energy intake by about 20%, does result in a significant increase in total daily energy intake. Our target is to achieve a completely normal nutritional status. Long term follow-up of these patients has shown significantly better survival in patients who achieve normal nutritional status. The advent of lung transplantation has added another dimension. In our experience, following a successful lung transplant, most patients no longer need their supplemental gastrostomy feeding.

SUMMARY

Our clinic policy is to encourage a high fat diet (35-40% total energy) and our patients grow normally in height and weight until their lung disease deteriorates significantly. Patients who develop a negative energy balance seldom if ever respond to diet therapy and hence are candidates for supplemental nocturnal gastrostomy feeds. Gastrostomy fed patients constitute 3 to 5% of our total CF population of approximately 590 patients.

Longitudinal relationship among growth, nutritional status, and pulmonary function in children with cystic fibrosis: analysis of the Cystic Fibrosis Foundation National CF Patient Registry

OBJECTIVE

To determine prospectively the relationship among growth, nutritional status, and pulmonary function over a 4-year period in a large cohort of children with cystic fibrosis (CF).

STUDY DESIGN

CF Foundation National CF Patient Registry data collected from 1991 to 1995 for 968 children (507 male) aged 5 to 8 years with pancreatic insufficiency and forced expiratory volume in 1 second within 60% to 140% of predicted values (FEV(1)%) were analyzed longitudinally. Variables hypothesized to affect FEV(1)% included age, sex, z scores for height, weight, percent of height-appropriate body weight, and annual number of days hospitalized.

RESULTS

The significant decline in FEV(1)% was curvilinear and dependent on baseline FEV(1)%; children with initial FEV(1)% > or = 90 declined 2.6 U/y more than those with initial FEV(1)% <90. Boys gained but girls declined in z scores for height. Girls decreased in z scores for weight at a greater rate than boys. The z scores for weight and percent of height-appropriate body weight were significantly associated with longitudinal changes in FEV(1)%, after adjustment was done for hospitalizations.

CONCLUSIONS

Growth, nutritional status, and pulmonary function are not stable in prepubertal children with CF and pancreatic insufficiency. Important sex-related differences in growth occur before puberty. Growth and nutritional status are associated with changes in FEV(1)%, suggesting that nutritional intervention may slow the decline in pulmonary function in children with CF.

Randomized, double-blind, placebo-controlled pilot trial of megestrol acetate in malnourished children with cystic fibrosis

BACKGROUND

Undernutrition is common in patients with cystic fibrosis (CF). Nutritional rehabilitation has been shown to improve linear growth, pulmonary function, well-being, and resistance to infection in this population. The purpose of this study was to determine whether the administration of megestrol acetate (MA) induces weight gain in malnourished patients with CF, and to assess the composition of weight gain.

METHODS

In a randomized, placebo-controlled, double-blind, crossover study, 12 children with CF received MA (10 mg/kg/d) or placebo for 12 weeks, followed by a 12-week washout period, then the alternative treatment. Anthropometrics, caloric intake, and clinical assessment were obtained every 6 weeks; pulmonary function tests, biochemistry, hematology, cortisol, growth hormone, insulin, C-peptide, insulin-like growth factor-1, insulin-like growth factor binding protein-3, and dual-energy x-ray absorptiometry scans were obtained every 12 weeks.

RESULTS

Six children did not complete the study, three for reasons unrelated to the study, two because they developed diabetes while receiving MA, and one who had glucose intolerance while receiving the placebo. Average weight gain was 3.05 kg in the MA group and 0.3 kg in the placebo group. The change in weight z score was +0.76 in the MA group and -0.05 in the placebo group. The change in height z score was -0.06 in the MA group and +0.06 in the placebo group. Lean body mass and body fat increased by 1507 g and 1192 g respectively in the MA group. Pulmonary function tests improved in the MA group; serum cortisol levels decreased. Side effects included glucosuria, insomnia, hyperactivity, and irritability.

CONCLUSIONS

Weight, body fat, and lean body mass increased and pulmonary function improved in the children with CF given MA. Adrenal suppression, glucose intolerance, and diabetes are side effects.

Nutrition and lung function in cystic fibrosis patients: review

Complex interactions between nutrition, skeletal and respiratory muscle function and energy expenditure in cystic fibrosis patients exist. Malnutrition significantly contributes to muscle weakness in patients with chronic obstructive pulmonary disease of the adult or in cystic fibrosis in childhood. Together with a measurable increase in resting energy expenditure the malnutrition, as a consequence of pancreatic insufficiency, leads to pulmonary deterioration. Whether pulmonary disease, pancreatic insufficiency, increased energy expenditure or insufficient intake of nutrition are the starters for the destructive circle or whether the basic defect is responsible for some of the components interacting with each other remains to be determined.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when weight for height percentage is less than 85%, when there has been weight loss for greater than a two month period or when there has been no weight gain for two to three months (under five years old) or for six months (over five years old).

OBJECTIVES

To examine the evidence that in patients with cystic fibrosis supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH STRATEGY

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group specialised register and contacted the companies which market enteral feeds and reviewed their databases. Date of the most recent search of the Group's specialised register: November 1999.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in patients with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

There are no trials included in this review.

MAIN RESULTS

There are no trials included in this review.

REVIEWER'S CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in patients with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are invasive, expensive, and may have a negative effect on self esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement and it is disappointing that their efficacy has not been fully assessed by randomised controlled trials. With the more frequent recommendations to use enteral tube feeding as an early rather than a late intervention, this systematic review identifies the need for a multi-centre randomised controlled trial assessing both efficacy and possible adverse effects of enteral tube feeding in cystic fibrosis.

Pancreatic enzyme replacement therapy in cystic fibrosis: Australian guidelines. Pediatric Gastroenterological Society and the Dietitians Association of Australia

Pancreatic enzyme replacement therapy (PERT) is a major factor associated with achieving optimum growth and nutritional status in cystic fibrosis (CF) patients with pancreatic insufficiency and consequent malabsorption. Currently in Australian CF clinics policies for the usage of PERT vary considerably. This paper highlights the current issues related to fat absorption and use of PERT in CF. It also provides evidence to support the recommendation of a PERT dose based on a standard ratio of lipase units per gram of dietary fat consumed for individual patients. A consistent approach to PERT doses will facilitate identification of patients whose PERT intake increases their risk of fibrosing colonopathy and for whom gastroenterological review is warranted. Recent reports indicate that PERT intake can be reduced with a secondary improvement in growth and nutrition status as a consequence of increased dietetic input. These Australian guidelines for the judicious use of PERT in CF should lead not only to a refinement in nutritional management of patients with CF but should also facilitate an improvement in compliance with therapy due to sophistication in patient education materials. The Australian guidelines for the use of PERT in CF if correctly applied, will also provide patients and their families with a better understanding of the relationship between PERT and nutritional status.

Cystic fibrosis: nutritional consequences and management

Malnutrition is an adverse prognostic factor in cystic fibrosis, influencing the course of pulmonary disease and correlating inversely with survival. A positive energy balance between energy intake and the combination of total energy expenditure, energy losses and growth-related energy cost is essential to maintain normal nutritional status. Before starting nutritional supplementation, it is important to rule out pathological conditions that may have a deleterious effect on nutritional status: persistent exocrine pancreatic insufficiency, chronic bacterial pulmonary colonization, impaired glucose tolerance, specific nutritional deficits and associated disorders leading to a decrease of energy intake. Several methods are available, ranging from boosted oral nutrition to behavioural intervention, oral supplementation, enteral nutrition and, rarely, parenteral nutrition. The use of elemental nutrients for either oral supplementation or enteral nutrition seems of no nutritional benefit and is more expensive than conventional polymeric nutrients. Provided that the goals of the nutritional supplementation are fulfilled, simpler is often better.

Nutrition intervention for weight gain in cystic fibrosis: a meta analysis

OBJECTIVES

A meta analysis of the literature on treatment approaches to malnutrition in cystic fibrosis (CF) was conducted to evaluate the effectiveness of oral supplementation, enteral nutrition, parenteral nutrition, and behavioral intervention on weight gain before and after treatment.

STUDY DESIGN

Eighteen studies were reviewed: four behavioral, six supplement, five enteral nutrition, and three parenteral nutrition.

RESULTS

The weighted effect size for weight gain was large for each intervention: 1.51 behavioral, 1.62 oral, 1.78 enteral, and 2.20 parenteral intervention. All interventions produced a large effect for weight gain in patients with CF. A univariate analysis of variance indicated no significant difference among the four interventions, F(3, 17) = 0.87, p > 0.05. Effect size for calorie intake was also evaluated when data were available (N = 7 studies), yielding a sample size of three behavioral, two enteral, and two oral supplement studies. Analysis of variance indicated a significant effect for treatment, F(2,4) = 13.34, p < 0.05, with post hoc analysis indicating that the behavioral intervention had a greater effect size for calorie intake than oral supplement.

CONCLUSIONS

All interventions were effective in producing weight gain in patients with CF. Behavioral intervention appeared to be as effective in improving weight gain in patients with CF as more invasive medical procedures. These findings support continued research on nutrition intervention with patients with CF including controlled clinical trials of the interventions and long-term follow-up on the impact of nutrition on disease progression.

Enteral nutrition for patients with cystic fibrosis: comparison of a semi-elemental and nonelemental formula

OBJECTIVE

To determine whether differences in tolerance and absorption of fat and nitrogen exist between a semi-elemental nutritional formula without enzyme replacement and a nonelemental formula with enzyme replacement.

STUDY DESIGN

Sixteen patients (eight girls and eight boys) with cystic fibrosis, 4 to 20 years of age (12+/-1.3, mean +/- SEM), who were pancreatic insufficient completed two 6-day regimens of nocturnal continuous enteral feedings offered in random order. Forty-four percent of the total daily energy was consumed as enteral tube feedings, and the remaining oral dietary intake remained constant throughout the study. Seventy-two-hour fecal collections from each study period were analyzed for total fat, long-chain fatty acids (LCFAs), medium-chain fatty acids (MCFAs), and nitrogen.

RESULTS

Fat absorption was 80.2%+/-2.9% and 82.3%+/-3.1% (p = 0.58) for the semi-elemental and nonelemental formulas, respectively. Similarly, the coefficient of absorption of LCFAs was 69.5%+/-4.5% and 79.6%+/-3.4% (p = 0.30) for the semi-elemental and nonelemental formulas. Malabsorption of MCFAs contributed minimally to total fat malabsorption. There was no difference between formulas for MCFA or for nitrogen absorption, 83.7%+/-1.9% and 87.4%+/-1.4%, p = 0.48. All patients tolerated all feedings, and weight gained was 1.8+/-0.3 kg with no difference in weight gain between the trials.

CONCLUSION

A nonelemental formula, with enzyme replacement, is absorbed as well as a predigested formula in patients with CF who are pancreatic insufficient.

Long-term survival and nutritional data in patients with cystic fibrosis treated in a Danish centre

BACKGROUND

Adequate nutrition and optimal treatment of bronchopulmonary infections are both of critical importance in maintaining the health of patients with cystic fibrosis. The cystic fibrosis centre in Copenhagen has followed a regimen of very early and aggressive antimicrobial treatment, especially against Pseudomonas aeruginosa infection. An unrestricted diet of low fat and high protein without hyperalimentation was recommended before 1985 which was then changed to a high fat, high calorie intake.

METHODS

The overall impact of the treatment regimen was evaluated by a cross sectional analysis of all 223 patients who attended the centre in 1989. Growth and nutritional parameters were combined with lung function parameters and with a retrospective analysis of chronic P aeruginosa infection and its duration. Survival curves for all 313 patients treated at the centre since 1949 were calculated.

RESULTS

All the patients with cystic fibrosis had normal height, although the final height was achieved a little later than in healthy controls. Body weight was lower than normal in males above 15 and in females above 10 years of age. The body mass index (BMI), which was approximately 98% of normal in the younger patients, declined to 90% in adult men and to 83% in adult women with cystic fibrosis, and was strongly correlated with lung function parameters. In 1989 the median age of survival of all patients treated in the centre since 1949 was 30 years (32 years in males and 29 years in females).

CONCLUSIONS

The overall treatment regimen in the cystic fibrosis centre in Copenhagen is associated with growth and survival rates that are at least equal to those in other cystic fibrosis centres in other countries.

Behavioral intervention to improve calorie intake of children with cystic fibrosis: treatment versus wait list control

Changes in calorie intake and weight gain were evaluated in five children with cystic fibrosis (CF) who received behavioral intervention and four children with CF who served as wait list controls. The behavioral intervention was a 6-week group treatment that provided nutritional education plus management strategies aimed at mealtime behaviors that parents find most problematic. The control group was identified prospectively and was evaluated on all dependent measures at the same points in time pre- and posttreatment as the intervention group. Difference scores on calorie intake and weight gain from pre- to posttreatment were compared between groups using t tests for independent samples. The behavioral intervention group increased their calorie intake by 1,032 calories per day, while the control group's intake increased only 244 calories per day from pre- to posttreatment [t(6) = 2.826, p = 0.03]. The intervention group also gained significantly more weight (1.7 kg) than the control group (0 kg) over the 6 weeks of treatment [t(7) = 2.588, p = 0.03] and demonstrated catchup growth for weight, as indicated by improved weight Z scores (-1.18 to -0.738). The control group showed a decline in weight Z scores over this same time period (-1.715 to -1.76). One month posttreatment, the intervention was replicated with two of the four children from the control group. Improved calorie intake and weight gain pre- to posttreatment were again found in these children. At 3- and 6-month follow-up study of children receiving intervention, maintenance of calorie intake and weight gain was confirmed. No changes were found on pulmonary functioning, resting energy expenditure, or activity level pre- to posttreatment. This form of early intervention appears to be promising in improving nutritional status and needs to be investigated over a longer period of time to evaluate the effects of treatment gains on the disease process.

Dietary intakes of young children with cystic fibrosis: is there a difference?

Caloric intakes of preadolescent and adolescent girls and boys with cystic fibrosis (CF) were compared in order to evaluate the possibility that poor caloric intake contributes to poor nutritional status and high mortality among girls with CF. Fifty-six CF patients (26 girls and 30 boys), 10-15 years old, completed a 3-day food record, answered a short questionnaire, and underwent anthropometric and pulmonary function assessment. The mean ages of the girls and boys were similar, but the height and weight percentiles of the girls were lower than those of the boys (p = 0.02). Mean caloric intakes were no different (116% and 112% of the recommended nutrient intake in the girls and boys, respectively). Nutritional status, as determined by weight as a percentage of ideal weight for height, mean triceps skinfold thickness, and midarm muscle circumference, was normal and similar in both sexes. Most girls and boys with CF in this study had an appropriate perception of their body weight. Pulmonary function tests suggested mild lung disease with no significant difference between girls and boys (forced expiratory volume in 1 s of 82.2% and 79.8% of predicted values, respectively). The similar nutritional and pulmonary status of the girls and boys with CF in this age group is in contrast to previous reports. This finding may be the result of our policy, introduced > 15 years ago, of expecting normal growth, by paying close attention to enzyme therapy and encouraging high energy intake from the time of diagnosis. It remains to be seen whether boys and girls continue to maintain similar nutritional and pulmonary status at a later age and whether both sexes experience a similar mortality rate as they age.

Prolonged parenteral nutrition for cystic fibrosis patients

To evaluate the clinical impact of prolonged parenteral nutritional (PN) therapy on patients with advanced cystic fibrosis, we conducted a retrospective chart review of 25 cystic fibrosis patients who underwent prolonged PN (median course 295 days) at our institution between August 1988 and May 1992. The patients' survival status, change in percentage of ideal body weight, need for ongoing nutritional intervention, pulmonary function test changes, i.v. antibiotic use, and complication rates were assessed. Patients gained significant weight while receiving PN, but they lost weight when PN was discontinued. PN did not clearly improve pulmonary status. IV antibiotic therapy nearly doubled during PN. Central venous catheter sepsis rates rose from 1.29 to 3.45 per 1000 catheter days during PN therapy. In conclusion, prolonged PN promotes weight gain in cystic fibrosis patients with severe disease; however, the effect is transient and involves a significantly increased risk of sepsis.

Resting energy expenditures measured by indirect calorimetry are higher in preadolescent children with cystic fibrosis than expenditures calculated from prediction equations

OBJECTIVE

This study compared measured resting energy expenditures to resting energy expenditures calculated using Harris-Benedict equations (HBEs) and the Cystic Fibrosis Consensus Committee equations (CFCCEs).

DESIGN

We studied 31 preadolescent boys and girls with cystic fibrosis who ranged in age from 3.25 to 12.75 years old. The patients were afebrile and not in pulmonary distress. Measured resting energy expenditures were determined using a portable metabolic measurement cart with fully automated calibration and data management. The measured resting energy expenditures obtained were compared with values obtained using HBEs and CFCCEs.

RESULTS

For each patient, the measured resting energy expenditure value was above the predicted resting energy expenditure values derived from HBEs (P < or = .0001) and CFCCEs (P < or = .01).

APPLICATIONS

The HBEs and the CFCCEs underestimated the energy expenditures of the study population by 13% and 8%, respectively. These findings support the usefulness of the measurement of energy expenditures in determining the energy needs of preadolescent patients with cystic fibrosis. In clinical practice, the resting energy expenditures would be multiplied by activity coefficients to determine the total daily energy expenditures of this population.

Protein-energy malnutrition in cystic fibrosis patients

Protein-energy malnutrition with associated specific nutrient deficiencies is an important feature of cystic fibrosis and has been recognized as a poor prognostic factor. Therefore, the nutritional status of cystic fibrosis patients has to be evaluated regularly by diet diaries, clinical evaluation, anthropometry and more sophisticated methods, such as bioelectrical impedance analysis. Nutritional management, including nutritional rehabilitation programmes, of cystic fibrosis patients is well established today. Consequently, protein-energy malnutrition is no longer acceptable in cystic fibrosis patients, except perhaps in end-stage disease when lung transplantation is not considered.

Cost-benefit analysis of a national screening programme for cystic fibrosis in an Israeli population

The recently acquired ability to identify 97% of CF carriers in an Israeli Ashkenazi population, prompts an evaluation of a nationwide screening programme. In 1993, the programme would first screen and counsel 9,261 parents, then 396 spouses of carrier parents and finally screen 16.5 fetuses where both parents are carriers. Assuming 92% of screened parents choose abortion of fetus screened positive, 2.33 cases of CF will be prevented in 1993 at a direct cost of $781,000. The $326,000 direct costs of preventing a CF case, exceed the lifetime excess direct costs per case of $297,000. However, benefits of screening also accrue to subsequent pregnancies, resulting in a direct benefit ($14.45 million) to cost ($10.39 million) ratio of 1.39/1 for the period 1993-2032. When benefits and costs resulting from mortality changes, work absences and transport costs are included, the benefit ($15.95 million) to cost ($13.88 million) ratio falls to 1.15/1. Benefit-cost ratios are lower for other ethnic groups in Israel, due to lower carrier rates and lower mutation detection abilities. A CF screening programme will increase the freedom of individuals choice, but should be carried out carefully in order to minimize stigmatization and even discrimination against CF carriers.

Management dilemmas in the individual with cystic fibrosis and diabetes

As their life expectancy has improved, patients with cystic fibrosis (CF) have experienced an increasing incidence of diabetes. Hyperglycemia may adversely influence weight, pulmonary function, and development of microvascular complications. Strict control of blood glucose has not universally been sought, however. A program of multiple daily insulin injections and self-monitoring of blood glucose with an aim of normoglycemia is described in this article. The typical cystic fibrosis diet is variable in quantity and features a preponderance of simple carbohydrates; this is contrary to the usual diabetes meal plan. We describe the use of a flexible meal-planning system to establish individualized carbohydrate targets with specific insulin boluses titrated to each meal to control postprandial blood glucose excursions. Records of 22 patients followed for more than 1 year are reviewed. Mean (+/- standard error of the mean) glycosylated hemoglobin was reduced from 11.3 +/- 3.1% (at baseline) to 8.1 +/- 1.8% (at 1 year). Mean percent of ideal body weight also increased from 95.4 +/- 15.2 to 100 +/- 17.1. We conclude that strict metabolic control is an attainable goal in patients with cystic fibrosis and is associated with positive weight gain.

The nutritional consequences of gastrointestinal disease in adolescence

The growth spurt of adolescence, during which body weight nearly doubles and height increases by 16%, demands an increased delivery of nutrients by the gastrointestinal tract. Chronic disorders of digestion and absorption at this age, therefore have a potentially profound effect upon growth, skeletal maturation and sexual development. Moreover, the emotional climate of adolescence, which requires affiliation with peer groups, and a distancing from authority figures such as doctors and parents, is often associated with a deterioration in drug and dietary compliance and with erratic clinic attendance. Nutritional problems in adolescent patients with Crohn's disease, cystic fibrosis and coeliac disease are the most common. About one third of adolescents with Crohn's disease experience growth failure and delayed sexual development, probably as a consequence of long-term undernutrition. There is a strong argument for the care of these patients being in the hands of paediatric gastroenterologists. Enteral nutrition, often administered overnight, is successful in inducing catch-up growth, and reducing steroid dosage, although resection of diseased gut is often followed by good growth, and surgery should not be overlooked. Cystic fibrosis in adolescence is commonly complicated by protein-energy malnutrition. Pathogenesis includes anorexia, maldigestion and an increase in resting energy expenditure. Malnutrition has been treated by a number of enteral regimens. In general, there is no place for repeated, short-term interventions of less than 6 months. Long-term studies have all shown good nutritional repletion and growth, but results with respect to improved respiratory function are conflicting. More prospective control trials are needed before the precise indications for enteral nutrition in cystic fibrosis can be accurately defined. Once started it is difficult to stop, although preoperative treatment of patients awaiting heart-lung transplantation seems entirely appropriate. The major problem in the management of coeliac disease in adolescence is dietary compliance. Even those patients who claim to have good dietary compliance often have jejunal biopsy evidence of gluten ingestion and tend to be underweight. This is particularly worrying, as after 5 years adherence to a gluten free diet, the increased risk of gastrointestinal malignancy appears to return to normal.

Current issues in the nutritional management of children with cystic fibrosis

Recent evidence suggests that malnutrition has a negative impact on pulmonary function in children with cystic fibrosis. In the past, dietary management has aimed at high energy low fat intake, but this has recently been shown to fall far short of the 120-150% of the recommended daily allowance for energy cystic fibrosis patients require. This paper outlines the current principles of nutritional management for children with cystic fibrosis. These include a high energy, high fat containing diet (within limits of individual tolerance); high carbohydrate intake; high salt intake; replacement of fat-soluble vitamins; appropriate use of pancreatic enzyme preparations; and supplemental feeding when indicated. It is vital that a nutrition education programme be established for each child and his or her family so that the emphasis shifts from treatment of malnutrition to prevention. The long-term aim must be to promote an independent, healthy lifestyle which incorporates good nutrition and other healthy pursuits such as exercise.

Supplemental nasogastric feeding in cystic fibrosis patients during treatment for acute exacerbation of chest disease

The use of overnight, nasogastric, nutritional supplementation during hospitalization of children with cystic fibrosis (CF) receiving antibiotic therapy for acute exacerbations of respiratory disease was evaluated in 11 children (mean age = 7.75 years). Supplementary feeding significantly increased inpatient energy intake from 116 +/- 30% to 165 +/- 30% (P less than 0.001) of recommended dietary allowance with minimal effect on oral intake. It also resulted in significantly improved weight gains but neither increased energy intakes nor weights were sustained at short-term (mean = 5.7 weeks) or long-term (mean = 21.6 weeks) follow-up. The notion that short bursts of nasogastric feeding for inpatients with CF improve growth status is not supported. However, the study did show that treatment of chest infections alone does not positively affect spontaneous oral energy intake.

Fat intake is low in cystic fibrosis despite unrestricted dietary practices

A prospective study of caloric intake and specific nutrient composition was performed in 64 cystic fibrosis patients aged 0.3 to 18 yr. Linear regressions and multiple stepwise regressions revealed no significant correlations between any individual dietary parameter and age, height, weight, percentile of weight or height, Shwachman Score, and pulmonary parameters. The caloric intake varied widely in individual patients and in different age groups. Despite unrestrictive dietary practices, the fat intake (33.7% +/- 8) was below that recommended for these linoleate deficient patients.

Home teaching of nocturnal nasogastric feeding

Nocturnal nasogastric feeding (NGF) supplementation is an effective means of supplying calories to children with chronic diseases which may impair caloric and nutritional intake. Herein, we describe our experience with 18 patients who were taught NGF. They were divided into two groups: one group was instructed in the hospital which is the typical situation, whereas the second group was instructed at home. No complications were associated with NGF taught either at home or in the hospital. Our experience, therefore, indicates that nocturnal NGF can be successfully taught at home.

A comparison of survival, growth, and pulmonary function in patients with cystic fibrosis in Boston and Toronto

Two cystic fibrosis (CF) clinic populations of similar size and age distribution were compared with respect to growth, pulmonary function, and survival. Height and weight measurements were made on 499 patients in Boston (mean +/- SD age 15.9 +/- 9.6, range 1 month to 45 years) and on 534 patients in Toronto (mean +/- SD age 15.2 +/- 8.3, range 1 month to 43 years). Males constituted 57% in the Boston group, 58% in Toronto. Pulmonary function test results were recorded for 64% of the Boston patients and 77% of the Toronto patients. Survival curves for the period 1972-1981 generated by the CF Patient Registry were compared. Patients in Boston tended to be shorter than patients in Toronto. This pattern was seen in both sexes in the 10-20 year age groups. Toronto males also weighed more than Boston males. Mean forced expiratory volume in one second (FEV1) was not different in Boston and Toronto CF patients whether expressed as a percent of predicted or in litres by age groups. Median age of survival in Boston was 21 years, in Toronto 30, the two curves showing a marked separation from age 10. Although progressive pulmonary disease is the major cause of mortality in cystic fibrosis, the differences in growth and survival in these two patient groups, with very similar age-specific pulmonary function, suggest further examination of nutritional guidance and intervention in CF, especially regarding the traditional restriction of dietary fat.

Permanent enteral feeding in cystic fibrosis: advantages of a replaceable jejunostomy tube

A feeding jejunostomy constructed by the Witzel technique has been used to supplement 12 wasted patients with cystic fibrosis during 260 patient months. None of the patients has stopped the nocturnal feeding once started on the program. The preferred tube was the Entriflex enteral feeding tube, which, when placed without internal fixation, could be easily changed as necessary. There have been no major complications. Minor complications include tube blockage, dislodgement, local infection, and leakage around the tube causing granuloma formation. We have not lost the use of any of the jejunostomies because of inability to replace the tube when it has been dislodged.

Effect of dietary fat and residues on fecal loss of sterols and on their microbial degradation in cystic fibrosis

Although various etiologic factors have been implicated, the mechanism responsible for bile acid malabsorption in CF remains unknown. Eight CF children studied twice on a normal diet supplemented with pancreatic enzymes and once during a one-month period of Vivonex administered by continuous nasogastric infusion were compared to age-matched controls. On the fat and residue-free elemental diet, there was a modest decrease in steatorrhea and no change in the daily excretion of nitrogen and neutral sterols. However, normalization of bile acid output (485.6 +/- 65.0 to 160.6 +/- 29.2 mg/24 hr) to control levels (150.2 +/- 60.7) was noted. Diminished microbial degradation of both neutral and acidic sterols and a smaller amount of bile acids adsorbed to decreased residues were also found. The data do not support the possibility of a bile acid ileal transport defect and suggest that the most important single factor responsible for the intraluminal sequestration of bile acids in CF is dietary residues. Because of significant ongoing losses of nitrogen and lipids, pancreatic enzymes should be given to CF patients on elemental diets.

Modulation of human erythrocyte shape and fatty acids by diet

A semi-synthetic diet (Vivonex) was administered via nasogastric tube to three cystic fibrosis patients with pancreatic exocrine deficiency for 14 days to gain weight. Dietary essential fatty acids were provided as safflower oil, which constituted 1.3% of total calories. Plasma and red blood cells were analyzed for the content and composition of lipids at the start of the diet and at days 7 and 14 of the dietary period, and the results were correlated with the morphology of the cells. Feeding Vivonex to the patients led to an essential fatty acid deficiency, which was manifested in a 50% decrease in the linoleic acid content of the phosphatidylcholine of plasma and red blood cells at days 7 and 14 and in a 20% decrease in the linoleic acid content of red cell phosphatidylethanolamine at day 14. There was no significant alteration in the levels or composition of the other phospholipid classes and in the free cholesterol/phospholipid ratio. The decrease in the linoleic acid content of the erythrocytes was accompanied by a dramatic increase in the proportion of cells as echinocytes. We conclude that restricted linoleic acid availability in cystic fibrosis patients causes a change in red blood cell shape either directly by decreasing the linoleoylphosphatidylcholine content of the membrane or indirectly by affecting enzyme activity.

Supplemental parenteral nutrition in cystic fibrosis

The efficacy and safety of short-term supplemental peripheral hyperalimentation (PH) was evaluated in 15 hospitalized cystic fibrosis (CF) patients who exhibited varying degrees of pulmonary disease severity and nutritional impairment. An average of 1000 supplemental calories/day were administered intravenously for a 2- to 3-week period to patients being treated with parenteral antibiotics for exacerbation of their pulmonary disease. Eleven of 15 patients responded with a weight gain of greater than 2.0 kg and showed continued weight gain and stabilized pulmonary status for the 6- to 12-month follow-up period; two patients showed dramatic reversal of poor weight gain and growth following PH. Total calorie intake (oral + PH) equaled 141 +/- 40% of the recommended dietary allowances (RDA) in responders, with 45 +/- 12% RDA contributed by PH, in contrast to 68 +/- 20% of the RDA for total calories with 31 +/- 13% supplied using PH achieved in the nonresponders. Linoleic acid deficiency was documented in these patients (linoleic acid level as a percent of total fatty acid = 21.9% +/- 1.41 SEM vs 31.8% +/- 1.16 SEM in normal controls), and all seven patients achieved normalization of linoleic acid level after PH. Prior assessment of nutritional status (anthropometric measurements) or of severity of pulmonary disease (NIH clinical score) did not allow prediction of response to PH. No complications resulted from administration of PH to these hospitalized CF patients.

Chronic jejunostomy feeding with a non-elemental formula in undernourished patients with cystic fibrosis

Ten patients with cystic fibrosis, moderate to severe lung disease (forced expiratory flow % predicted 26.0, 15.7 [SD]), and undernutrition resistant to oral supplementation have been treated for 10 to 36 months with night-time feeds of a non-elemental formula given via a jejunostomy. All patients gained some weight and showed a significant increase in weight for height (change % wt/ht 8.1, 6.0 [SD] and mid-arm muscle circumference (change MAMC % standard 6.2, 5.7 [SD]). Although the forced expiratory flow indicated progression of the small airways disease during the period of feeding, the forced vital capacity did not significantly decline. In nine patients improvement in % wt/ht was maintained. One patient tolerated the feeding poorly and died of severe pulmonary disease after 10 months. The non-elemental formula used cost less than half that of an elemental formula. The jejunostomy tubes were unobtrusive and secured with only a small transparent dressing, which facilitated replacement. No serious complications resulted from jejunostomy feeding.

Tube feeding of infants and children

Advances in tube feeding methods, equipment, and formulas have helped to make this form of nutritional support appropriate for and well tolerated by children with a wide variety of clinical problems. This article describes advances in the field of enteral feeding and discusses the management of common problems associated with this technique.