Effect of an organized lipid matrix on lipid absorption and clinical outcomes in patients with cystic fibrosis

Fat malabsorption in short bowel syndrome: A review of pathophysiology and management

Fat malabsorption is central to the pathophysiology of short bowel syndrome (SBS). It occurs in patients with insufficient intestinal surface area and/or function to maintain metabolic and growth demands. Rapid intestinal transit and impaired bile acid recycling further contribute to fat malabsorption. A significant portion of patients require parenteral nutrition (PN) for their survival but may develop sepsis and liver dysfunction as a result. Despite advancements in the treatment of SBS, fat malabsorption remains a chronic issue for this vulnerable patient population. Peer-reviewed literature was assessed on the topic of fat malabsorption in SBS. Current management of patients with SBS involves dietary considerations, PN management, antidiarrheals, glucagon-like peptide 2 agonists, and multidisciplinary teams. Clinical trials have focused on improving intestinal fat absorption by facilitating fat digestion with pancreatic enzymes. Targeting fat malabsorption in SBS is a potential pathway to improving lifestyle and reducing morbidity and mortality in this rare disease.

Updates in Nutrition Management of Cystic Fibrosis in the Highly Effective Modulator Era

Attainment and maintenance of good nutrition has been an important aspect of management in cystic fibrosis (CF) for decades. In the era of highly effective modulator therapy for CF, the quality of the nutrients we recommend is increasingly important. Our therapy must support our patients' health for many years beyond what we previously thought. Preventing cardiovascular disease, reducing hyperlipidemia, and optimizing lean body mass for active, longer lives now join the long-standing goal of promoting lung function through nutrition. This chapter summarizes recent developments in nutrition in people with CF, with an eye to the evolution of our practice.

Improved residual fat malabsorption and growth in children with cystic fibrosis treated with a novel oral structured lipid supplement: A randomized controlled trial

Background

In the primary analysis of a 12-month double-blind randomized active placebo-controlled trial, treatment of children with cystic fibrosis (CF) and pancreatic insufficiency (PI) with a readily absorbable structured lipid (Encala™, Envara Health, Wayne, PA) was safe, well-tolerated and improved dietary fat absorption (stool coefficient of fat absorption [CFA]), growth, and plasma fatty acids (FA).

Objective

To determine if the Encala™ treatment effect varied by severity of baseline fat malabsorption.

Methods

Subjects (n = 66, 10.5±3.0 yrs, 39% female) with baseline CFA who completed a three-month treatment with Encala™ or a calorie and macronutrient-matched placebo were included in this subgroup analysis. Subjects were categorized by median baseline CFA: low CFA (<88%) and high CFA (≥88%). At baseline and 3-month evaluations, CFA (72-hour stool, weighed food record) and height (HAZ), weight (WAZ) and BMI (BMIZ) Z-scores were calculated. Fasting plasma fatty acid (FA) concentrations were also measured.

Results

Subjects in the low CFA subgroup had significantly improved CFA (+7.5±7.2%, mean 86.3±6.7, p = 0.002), and reduced stool fat loss (-5.7±7.2 g/24 hours) following three months of Encala^TM treatment. These subjects also had increased plasma linoleic acid (+20%), α-linolenic acid (+56%), and total FA (+20%) (p≤0.005 for all) concentrations and improvements in HAZ (0.06±0.08), WAZ (0.17±0.16), and BMIZ (0.20±0.25) (p≤0.002 for all). CFA and FA were unchanged with placebo in the low CFA group, with some WAZ increases (0.14±0.24, p = 0.02). High CFA subjects (both placebo and Encala™ groups) had improvements in WAZ and some FA.

Conclusions

Subjects with CF, PI and more severe fat malabsorption experienced greater improvements in CFA, FA and growth after three months of Encala™ treatment. Encala™ was safe, well-tolerated and efficacious in patients with CF and PI with residual fat malabsorption and improved dietary energy absorption, weight gain and FA status in this at-risk group.

Monoacylglycerol Form of Omega-3s Improves Its Bioavailability in Humans Compared to Other Forms

Numerous benefits are attributed to omega-3 fatty acids (OM3) especially in cardiovascular health. However, bioavailability and clinical efficacy depend on numerous factors, including OM3 form, food matrix effects (especially the lipid content of the diet), and metabolic capacity. Here, we show in humans that a "pre-digested" OM3-sn-1(3)-monoacylglycerol lipid structure (OM3-MAG) has a significantly greater absorption at high therapeutic doses (2.9 g/day) than the most commonly OM3-ethyl ester (3.1 g/day) form (used for the treatment of hypertriglyceridemia), and a comparable profile to other pre-digested OM3 free fatty acids (OM3-FFA) structure (3.2 g/day). Nutritional supplement doses of MAG resulted in similar increases in OM3 blood level, compared to OM3 triacylglycerols (OM3-TAG) supplements in obese subjects (1.2 g/day) under low fat diet, and in children with cystic fibrosis (1.0 g/day). These results suggest that both forms of pre-digested OM3-MAG and OM3-FFA are effectively absorbed and re-incorporated effectively into triacylglycerols inside the enterocytes, before being exported into the chylomicrons lipid transport system. The pre-digested OM3-MAG might provide a more effective therapy in severe cardiovascular conditions where high doses of OM3 are required and a low-fat diet is indicated, which limited digestive lipase activity.

Antioxidant Micronutrients and Essential Fatty Acids Supplementation on Cystic Fibrosis Outcomes: A Systematic Review

BACKGROUND

Antioxidant micronutrients and essential fatty acids supplementation intake appears to have a protective effect in some diseases such as cardiovascular disease, cancer, and asthma.

OBJECTIVE

The aim of this study was to perform a systematic review to evaluate the effects of these nutrients on nutritional and clinical outcomes of patients with cystic fibrosis (CF).

METHODS

This is a systematic review of randomized clinical trials (RCTs) in CF. MEDLINE (via PubMed), Embase, and Scopus databases were searched for RCTs published from 1948 through February 2019. Two investigators independently reviewed the titles and abstracts and then extracted the data from the included studies using a standardized predesigned form. Two reviewers independently performed the quality assessment of the RCTs according to the Cochrane risk of bias tools.

RESULTS

A total of 4,792 studies were identified, and 23 were eligible (8 antioxidant micronutrient and 15 essential fatty acids). The interventions found were beta-carotene, zinc, magnesium, multivitamin, docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), linoleic acid and lipid matrix with choline supplementation. A significant improvement was observed in: (a) pulmonary function with magnesium (n=1) and essential fatty acids (n=2) supplementation; (b) less pulmonary exacerbations with beta-carotene (n=1), zinc (n=1), antioxidant-enriched multivitamin (n=1) and essential fatty acids (n=2) supplementation. One study with antioxidant-enriched multivitamin and four studies with EPA/DHA supplementation reported significant reductions in inflammatory markers. Nutritional status was not modified by antioxidants supplementation in any of the studies, while in five studies there was an improvement with fatty acids supplementation. The risk of bias of the majority of the parallel studies was high.

CONCLUSIONS

The benefits of antioxidants or DHA/EPA supplementation for CF, although observed in some studies, are not consistent enough to recommend routine use of these supplements. The mechanisms of action of these nutrients, dose levels and timing should be further explored in future studies.

Adherence to Nutritional Supplementation in Cystic Fibrosis

PURPOSE

The purpose of this study was to examine patterns of adherence to a novel dietary supplement in pediatric cystic fibrosis. Adherence to dietary supplementation in cystic fibrosis is challenging, and examination of patterns of adherence behavior over time is needed to better characterize subgroups of patients who need self-management support.

DESIGN AND METHODS

We prospectively examined adherence to Lym-X-Sorb™ (LXS), an organized lipid matrix dietary supplementation for patients with cystic fibrosis (CF) and pancreatic insufficiency (PI), over a 12-month period. Adherence for participants aged 5-17 years with CF and PI (N = 109) was monitored monthly via supplement packet counts. Group-based trajectory modeling was employed to examine patterns in adherence behavior over time.

RESULTS

Four distinct trajectories best characterized adherence in this sample, with 18% of participants demonstrating near perfect adherence, 42% demonstrating good adherence (at or above 80%), 16% demonstrating poor adherence that declined over time, and 24% demonstrating significant non-adherence (< 30%).

CONCLUSIONS

Some patients with CF and PI who are prescribed nutritional supplements will require intensive, individualized behavioral intervention to enhance adherence. Identifying patients who will have difficulty adhering to dietary interventions may result in better treatment-to-patient matching and improved adherence promotion efforts.

PRACTICE IMPLICATIONS

Assessment of adherence to dietary supplementation over time can identify patients at risk for continued difficulty with self-management and provide opportunities for early intervention.

Oral calorie supplements for cystic fibrosis

BACKGROUND

Poor nutrition occurs frequently in people with cystic fibrosis and is associated with other adverse outcomes. Oral calorie supplements are used to increase total daily calorie intake and improve weight gain. However, they are expensive and there are concerns they may reduce the amount of food eaten and not improve overall energy intake. This is an update of a previously published review.

OBJECTIVES

To establish whether in people with cystic fibrosis, oral calorie supplements: increase daily calorie intake; and improve overall nutritional intake, nutritional indices, lung function, survival and quality of life. To assess adverse effects associated with using these supplements.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register comprising references from comprehensive electronic database searches, handsearches of relevant journals and abstract books of conference proceedings. We contacted companies marketing oral calorie supplements.Last search: 18 October 2016.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing use of oral calorie supplements for at least one month to increase calorie intake with no specific intervention or additional nutritional advice in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

We independently selected the included trials, assessed risk of bias and extracted data. We contacted the authors of included trials and obtained additional information for two trials.

MAIN RESULTS

We identified 21 trials and included three, reporting results from 131 participants lasting between three months and one year. Two trials compared supplements to additional nutritional advice and one to no intervention. Two of the included trials recruited only children. In one trial the risk of bias was low across all domains, in a second trial the risk of bias was largely unclear and in the third mainly low. Blinding of participants was unclear in two of the trials. Also, in one trial the clinical condition of groups appeared to be unevenly balanced at baseline and in another trial there were concerns surrounding allocation concealment. There were no significant differences between people receiving supplements or dietary advice alone for change in weight, height, body mass index, z score or other indices of nutrition or growth. Changes in weight (kg) at three, six and 12 months respectively were: mean difference (MD) 0.32 (95% confidence interval (CI) -0.09 to 0.72); MD 0.47 (95% CI -0.07 to 1.02 ); and MD 0.16 (-0.68 to 1.00). Total calorie intake was greater in people taking supplements at 12 months, MD 265.70 (95% CI 42.94 to 488.46). There were no significant differences between the groups for anthropometric measures of body composition, lung function, gastro-intestinal adverse effects or activity levels. Moderate quality evidence exists for the outcomes of changes in weight and height and low quality evidence exists for the outcomes of change in total calories, total fat and total protein intake as results are applicable only to children between the ages of 2 and 15 years and many post-treatment diet diaries were not returned. Evidence for the rate of adverse events in the treatment groups was extremely limited and judged to be of very low quality AUTHORS' CONCLUSIONS: Oral calorie supplements do not confer any additional benefit in the nutritional management of moderately malnourished children with cystic fibrosis over and above the use of dietary advice and monitoring alone. While nutritional supplements may be used, they should not be regarded as essential. Further randomised controlled trials are needed to establish the role of short-term oral protein energy supplements in people with cystic fibrosis and acute weight loss and also for the long-term nutritional management of adults with cystic fibrosis or advanced lung disease, or both.

Determinants of Serum Glycerophospholipid Fatty Acids in Cystic Fibrosis

The etiology of altered blood fatty acid (FA) composition in cystic fibrosis (CF) is understood only partially. We aimed to investigate the determinants of serum glycerophospholipids’ FAs in CF with regard to the highest number of FAs and in the largest cohort to date. The study comprised 172 CF patients and 30 healthy subjects (HS). We assessed Fas’ profile (gas chromatography/mass spectrometry), CF transmembrane conductance regulator (CFTR) genotype, spirometry, fecal elastase-1, body height and weight Z-scores, liver disease, diabetes and colonization by Pseudomonas aeruginosa. The amounts of saturated FAs (C14:0, C16:0) and monounsaturated FAs (C16:1n-7, C18:1n-9, C20:1n-9, C20:3n-9) were significantly higher in CF patients than in HS. C18:3n-6, C20:3n-6 and C22:4n-6 levels were also higher in CF, but C18:2n-6, C20:2n-6 and C20:4n-6, as well as C22:6n-3, were lower. In a multiple regression analysis, levels of seven FAs were predicted by various sets of factors that included age, genotype, forced expiratory volume in one second, pancreatic status and diabetes. FA composition abnormalities are highly prevalent in CF patients. They seem to be caused by both metabolic disturbances and independent clinical risk factors. Further research into the influence of CFTR mutations on fat metabolism and desaturases’ activity is warranted.

Effect of Oral Lipid Matrix Supplement on Fat Absorption in Cystic Fibrosis: A Randomized Placebo-Controlled Trial

Pancreatic enzyme therapy does not normalize dietary fat absorption in patients with cystic fibrosis and pancreatic insufficiency. Efficacy of LYM-X-SORB (LXS), an easily absorbable lipid matrix that enhances fat absorption, was evaluated in a 12-month randomized, double-blinded, placebo-controlled trial with plasma fatty acids (FA) and coefficient of fat absorption (CFA) outcomes. A total of 110 subjects (age 10.4 ± 3.0 years) were randomized. Total FA increased with LXS at 3 and 12 months (+1.58, +1.14 mmol/L) and not with placebo (P = 0.046). With LXS, linoleic acid (LA) increased at 3 and 12 months (+298, +175 nmol/mL, P ≤ 0.046), with a 6% increase in CFA (P < 0.01). LA increase was significant in LXS versus placebo (445 vs 42 nmol/mL, P = 0.038). Increased FA and LA predicted increased body mass index Z scores. In summary, the LXS treatment improved dietary fat absorption compared with placebo as indicated by plasma FA and LA and was associated with better growth status.

Choline Supplementation With a Structured Lipid in Children With Cystic Fibrosis: A Randomized Placebo-Controlled Trial

BACKGROUND

Choline depletion is seen in cystic fibrosis (CF) and pancreatic insufficiency in spite of enzyme treatment and may result in liver, fatty acid, and muscle abnormalities. This study evaluated the efficacy and safety of an easily absorbed choline-rich structured lipid (LYM-X-SORB™ [LXS]) to improve choline status.

METHODS

Children with CF and pancreatic insufficiency were randomized to LXS or placebo in a 12-month double blind trial. Dietary choline intake, plasma cholines, plasma and fecal phospholipids, coefficient of fat absorption, pulmonary function, growth status, body composition, and safety measures were assessed. Magnetic resonance spectroscopy for calf muscle choline and liver fat were assessed in a subgroup and compared with a healthy comparison group matched for age, sex, and body size.

RESULTS

A total of 110 subjects were enrolled (age 10.4 ± 3.0 years). Baseline dietary choline, 88% recommended, increased 3-fold in the LXS group. Plasma choline, betaine, and dimethylglycine increased in the LXS but not placebo (P = 0.007). Plasma lysophosphatidylcholine and phosphatidylcholine increased, and fecal phosphatidylcholine/phosphatidylethanolamine ratio decreased (P ≤ 0.05) in LXS only, accompanied by a 6% coefficient of fat absorption increase (P = 0.001). Children with CF had higher liver fat than healthy children and depleted calf muscle choline at baseline. Muscle choline concentration increased in LXS and was associated with improvement in plasma choline status. No relevant changes in safety measures were evident.

CONCLUSIONS

LXS had improved choline intake, plasma choline status, and muscle choline stores compared with placebo group. The choline-rich supplement was safe, accepted by participants, and improved choline status in children with CF.

Choline supplementation alters some amino acid concentrations with no change in homocysteine in children with cystic fibrosis and pancreatic insufficiency

The present study determined the plasma amino acid status in children with cystic fibrosis (CF) and pancreatic insufficiency (PI) in the modern medical and nutritional care setting and investigated the effect of choline supplementation on amino acid status. A total of 110 children aged 5 to 18 years with CF and PI were randomized to receive choline-enriched structured lipid (LYM-X-SORB) or placebo with similar energy and fat content. Plasma amino acids were measured at baseline and 3 and 12 months. We hypothesized that choline supplementation would result in lower plasma homocysteine concentrations in children with CF. At baseline, dietary protein intake was high and the amino acid profile was within laboratory reference ranges in most participants. Alanine and cysteine were elevated in 24% and 36% of participants, respectively. Children with baseline alanine above reference range had improved weight, body mass index, and fat-free mass. Low homocysteine was found in 62% of children 11 years and older. After 3 and 12 months, there was no effect of choline supplementation on methionine or homocysteine status. Compared with placebo, choline supplementation resulted in increased glycine and decreased threonine, histidine, valine, and total branch chained amino acids at 12 months. In conclusion, daily choline supplementation with LYM-X-SORB did not alter methionine-homocysteine metabolism but did result in alterations in other amino acids in children with CF and PI.

Oral protein calorie supplementation for children with chronic disease

BACKGROUND

Poor growth and nutritional status are common in children with chronic diseases. Oral protein calorie supplements are used to improve nutritional status in these children. These expensive products may be associated with some adverse effects, e.g. the development of inappropriate eating behaviour patterns. This is a new update of a Cochrane review last updated in 2009.

OBJECTIVES

To examine evidence that in children with chronic disease, oral protein calorie supplements alter daily nutrient intake, nutritional indices, survival and quality of life and are associated with adverse effects, e.g. diarrhoea, vomiting, reduced appetite, glucose intolerance, bloating and eating behaviour problems.

SEARCH METHODS

Trials of oral protein calorie supplements in children with chronic diseases were identified through comprehensive electronic database searches, handsearching relevant journals and abstract books of conference proceedings. Companies marketing these products were also contacted.Most recent search of the Group's Trials Register: 24 February 2015.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing oral protein calorie supplements for at least one month to increase calorie intake with existing conventional therapy (including advice on improving nutritional intake from food or no specific intervention) in children with chronic disease.

DATA COLLECTION AND ANALYSIS

We independently assessed the outcomes: indices of nutrition and growth; anthropometric measures of body composition; calorie and nutrient intake (total from oral protein calorie supplements and food); eating behaviour; compliance; quality of life; specific adverse effects; disease severity scores; and mortality; we also assessed the risk of bias in the included trials.

MAIN RESULTS

Four studies (187 children) met the inclusion criteria. Three studies were carried out in children with cystic fibrosis and one study included children with paediatric malignant disease. Overall there was a low risk of bias for blinding and incomplete outcome data.Two studies had a high risk of bias for allocation concealment. Few statistical differences were found in the outcomes we assessed between treatment and control groups, except change in total energy intake at six and 12 months, mean difference 304.86 kcal per day (95% confidence interval 5.62 to 604.10) and mean difference 265.70 kcal per day (95% confidence interval 42.94 to 485.46), respectively. However, these were based on the analysis of just 58 children in only one study. Only two chronic diseases were included in these analyses, cystic fibrosis and paediatric malignant disease. No other studies were identified which assessed the effectiveness of oral protein calorie supplements in children with other chronic diseases.

AUTHORS' CONCLUSIONS

Oral protein calorie supplements are widely used to improve the nutritional status of children with a number of chronic diseases. We identified a small number of studies assessing these products in children with cystic fibrosis and paediatric malignant disease, but were unable to draw any conclusions based on the limited data extracted. We recommend a series of large, randomised controlled trials be undertaken investigating the use of these products in children with different chronic diseases. Until further data are available, we suggest these products are used with caution.

Oral calorie supplements for cystic fibrosis

BACKGROUND

Poor nutrition occurs frequently in people with cystic fibrosis (CF) and is associated with other adverse outcomes. Oral calorie supplements are used to increase total daily calorie intake and improve weight gain. However, they are expensive and there are concerns they may reduce the amount of food eaten and not improve overall energy intake.

OBJECTIVES

To establish whether in people with CF, oral calorie supplements: increase daily calorie intake; and improve overall nutritional intake, nutritional indices, lung function, survival and quality of life. To assess adverse effects associated with using these supplements.

SEARCH METHODS

We searched the Cochrane CF Trials Register comprising references from comprehensive electronic database searches, handsearches of relevant journals and abstract books of conference proceedings. We contacted companies marketing oral calorie supplements.Last search: 03 July 2014.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing use of oral calorie supplements for at least one month to increase calorie intake with no specific intervention or additional nutritional advice in people with CF.

DATA COLLECTION AND ANALYSIS

We independently selected the included trials, assessed risk of bias and extracted data. We contacted the authors of included trials and obtained additional information for two trials.

MAIN RESULTS

We identified 21 trials and included three, reporting results from 131 participants lasting between three months and one year. Two trials compared supplements to additional nutritional advice and one to no intervention. Two of the included trials recruited only children. In one trial the risk of bias was low across all domains, in a second trial the risk of bias was largely unclear and in the third mainly low. Blinding of participants was unclear in two of the trials. Also, in one trial the clinical condition of groups appeared to be unevenly balanced at baseline and in another trial there were concerns surrounding allocation concealment. There were no significant differences between people receiving supplements or dietary advice alone for change in weight, height, body mass index, z score or other indices of nutrition or growth. Changes in weight (kg) at three, six and twelve months respectively were: MD 0.32 (95% CI -0.09 to 0.72); MD 0.47 (95% CI -0.07 to 1.02 ); and MD 0.16 (-0.68 to 1.00). Total calorie intake was greater in people taking supplements at 12 months, MD 265.70 (95% CI 42.94 to 488.46). There were no significant differences between the groups for anthropometric measures of body composition, lung function, gastrointestinal adverse effects or activity levels.

AUTHORS' CONCLUSIONS

Oral calorie supplements do not confer any additional benefit in the nutritional management of moderately malnourished children with CF over and above the use of dietary advice and monitoring alone. While nutritional supplements may be used, they should not be regarded as essential. Further randomised controlled trials are needed to establish the role of short-term oral protein energy supplements in people with CF and acute weight loss and also for the long-term nutritional management of adults with CF or advanced lung disease, or both.

Effect of a dietary intervention on growth and energy expenditure in children with cystic fibrosis

BACKGROUND

The study aim was to determine the effect of a dietary intervention on growth, body composition and resting energy expenditure (REE) in children with cystic fibrosis (CF) and pancreatic insufficiency (PI) in a randomized, double blind, placebo-controlled trial.

METHODS

Subjects (5 to 17 yrs) participated in a 12-month trial of the organized lipid matrix LYM-X-SORB™ (LXS) vs. placebo dietary supplements with similar calories, total fat and fatty acids. Dietary intake was assessed using 3-day weighed food records. Height (HAZ), weight (WAZ), BMI (BMIZ), mid-upper arm muscle (UAMAZ) and fat area (UAFAZ) Z-scores were calculated. Fat mass (FM) and fat-free mass (FFM) were obtained by whole body DXA. REE (kcal/d) was evaluated by indirect calorimetry at baseline, 3 and 12 months and %REE calculated using Schofield equations. No growth or REE differences were observed between LXS and placebo groups so data were pooled for analysis.

RESULTS

63 children (57% males, age 10.6 ± 2.9 yr, 43% receiving LXS) completed REE measurements. Caloric intake increased from a median of 2502 [1478, 4909] to 2616 [1660, 4125] kcal/d at 12 months. HAZ, WAZ and UAMAZ increased (p < 0.05) over 12 months. Mean REE was 109 ± 8% predicted at baseline and 107 ± 9% at 12 months (p < 0.05). REE (kcal/d) adjusted for FFM and FM decreased over 12 months ([mean ± SE] -31 ± 12 kcals, p < 0.01), significant only in males (-49 ± 16 kcals, p < 0.01).

CONCLUSIONS

Over a 12 month nutrition intervention with either LXS or placebo, the growth status, muscle stores and REE improved. Sustained increased energy intake improved energy metabolism, growth and nutritional status in school age children with CF, PI and mild lung disease.

Vitamin B(12) status in children with cystic fibrosis and pancreatic insufficiency

OBJECTIVES

Unexpectedly high serum B12 concentrations were noted in most study subjects with cystic fibrosis (CF) and pancreatic insufficiency (PI) participating in a nutrition intervention at the baseline evaluation. The objectives of this study were to determine dietary, supplement-based, and enzyme-based B12 intake, serum B12 concentrations, and predictors of vitamin B12 status in children with CF and PI.

STUDY DESIGN

Serum B12 status was assessed in subjects (5-18 years) and categorized as elevated (serum B12 above reference range for age and sex [Hi-B12]) or within reference range (serum B12 within reference range for age and sex) for age and sex. Serum homocysteine, plasma B6, red blood cell folate, height, weight, and body mass index z scores, pulmonary function, energy, and dietary and supplement-based vitamin intake were assessed.

RESULTS

A total of 106 subjects, mean age 10.4 ± 3.0 years, participated in the study. Median serum B12 was 1083 pg/mL, with 56% in the Hi-B12 group. Dietary and supplement-based B12 intakes were both high representing 376% and 667% recommended dietary allowance (RDA), respectively. The Hi-B12 group had significantly greater supplement-based B12 intake than the serum B12 within reference range for age and sex group (1000% vs 583% RDA, P < 0.001). Multiple logistic regression analysis showed that high supplement-based B12 intake and age >12 years increased the risk of Hi-B12, whereas higher forced expiratory volume at 1 second (FEV1) decreased the risk (pseudo-R = 0.18, P < 0.001).

CONCLUSIONS

Serum B12 was elevated in the majority of children with CF and PI. Supplement-based B12 intake was 6 to 10 times the RDA, and strongly predicted elevated serum B12 status. The health consequences of lifelong high supplement-based B12 intake and high serum B12 are unknown and require further study, as does the inversed correlation between serum B12 and forced expiratory volume at 1 second.

Fat-soluble vitamins in cystic fibrosis and pancreatic insufficiency: efficacy of a nutrition intervention

OBJECTIVES

The aim of the study was to assess the impact of LYM-X-SORB (LXS), an organized lipid matrix that has been shown to be absorbable without pancreatic enzyme therapy on fat-soluble vitamin status in children with cystic fibrosis (CF) and pancreatic insufficiency (PI).

METHODS

Children with CF and PI were randomized to daily LXS or an isocaloric placebo comparison supplement for 12 months. Serum vitamins A (retinol), D (25-hydroxyvitamin D[25D]), E (α-tocopherol, α-tocopherol:cholesterol ratio), and K (percentage of undercarboxylated osteocalcin [%ucOC] and plasma proteins induced by vitamin K absence factor II [PIVKA II]) were assessed at baseline and 12 months. Dietary intake was determined using 3-day weighed food records and supplemental vitamin intake by a comprehensive questionnaire.

RESULTS

A total of 58 subjects (32 boys, age 10.3 ± 2.9 years [mean ± standard deviation]) with complete serum vitamin, dietary and supplemental vitamin data were analyzed. After adjusting for dietary and supplemental vitamin intake, serum retinol increased 3.0 ± 1.4 μg/dL (coefficient ± standard error) (adjusted R2 = 0.02, P = 0.03) and vitamin K status improved as demonstrated by a decreased percentage of undercarboxylated osteocalcin of -6.0% ± 1.6% by 12 months (adjusted R2 = 0.15, P < 0.001). These changes occurred in both the LXS and placebo comparison groups. No changes in serum 25D or α-tocopherol were detected. Both nutrition interventions increased caloric intake a mean of 83 ± 666 kcal/day by 12 months.

CONCLUSIONS

Vitamins A and K status improved, whereas vitamins D and E status was unchanged during 12 months of LXS and isocaloric placebo comparison supplement in children with CF and PI.

Study design considerations for evaluating the efficacy and safety of pancreatic enzyme replacement therapy in patients with cystic fibrosis

In 2006, the US FDA issued a 'Guidance for Industry' regarding submission of New Drug Applications for pancreatic enzyme replacement therapy (PERT) products. Five oral delayed-release PERT products have been approved by the FDA, and several others are under development and/ or evaluation for New Drug Application submission. We present in this paper recommendations of the Cystic Fibrosis Foundation's Cystic Fibrosis (CF) Therapeutics Development Network and Data Safety Monitoring Board regarding study design considerations for evaluating PERT products in patients with CF. Careful attention to study design and accuracy of the outcome measures has confirmed our understanding of the efficacy and safety of PERT for the treatment of exocrine pancreatic insufficiency of CF.

Oral calorie supplements for cystic fibrosis

BACKGROUND

Poor nutrition occurs frequently in people with cystic fibrosis (CF) and is associated with other adverse outcomes. Oral calorie supplements are used to increase total daily calorie intake and improve weight gain. However, they are expensive and there are concerns they may reduce the amount of food eaten and not improve overall energy intake.

OBJECTIVES

To establish whether in people with CF, oral calorie supplements: increase daily calorie intake; and improve overall nutritional intake, nutritional indices, lung function, survival and quality of life. To assess adverse effects associated with using these supplements.

SEARCH METHODS

We searched the Cochrane CF Trials Register comprising references from comprehensive electronic database searches, handsearches of relevant journals and abstract books of conference proceedings. We contacted companies marketing oral calorie supplements.Last search: 19 July 2012.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing use of oral calorie supplements for at least one month to increase calorie intake with no specific intervention or additional nutritional advice in people with CF.

DATA COLLECTION AND ANALYSIS

We independently selected the included trials, assessed risk of bias and extracted data. We contacted the authors of included trials and obtained additional information for two trials.

MAIN RESULTS

We identified 21 trials and included three, reporting results from 131 participants. There were no significant differences between people receiving supplements or dietary advice alone for change in weight, height, body mass index, z score or other indices of nutrition or growth. Changes in weight (kg) at three, six and twelve months respectively were: MD 0.32 (95% CI -0.09 to 0.72); MD 0.47 (95% CI -0.07 to 1.02 ); and MD 0.16 (-0.68 to 1.00). Total calorie intake was greater in people taking supplements at 12 months, MD 265.70 (95% CI 42.94 to 488.46). There were no significant differences between the groups for anthropometric measures of body composition, lung function, gastrointestinal adverse effects or activity levels.

AUTHORS' CONCLUSIONS

Oral calorie supplements do not confer any additional benefit in the nutritional management of moderately malnourished children with CF over and above the use of dietary advice and monitoring alone. While nutritional supplements may be used, they should not be regarded as essential. Further randomised controlled trials are needed to establish the role of short-term oral protein energy supplements in people with CF and acute weight loss and also for the long-term nutritional management of adults with CF or advanced lung disease, or both.

In vitro cytotoxic activity of cationic paclitaxel nanoparticles on MDR-3T3 cells

Cationic paclitaxel nanoparticles were developed and the possible delivery mechanism was explored by cellular uptake studies. In vitro cytotoxicity of paclitaxel-loaded nanoparticles was evaluated with NIH-3T3 cells and multidrug resistant MDR-3T3 cells (with active P-glycoprotein). The IC(50)s of paclitaxel nanoparticles, liposomal paclitaxel, and Taxol((R)) on NIH-3T3 cells were 0.7 microg/mL, 3.0 microg/mL, and 3.6 microg/mL, respectively, and on MDR-3T3 cells changed to 1.4 microg/mL, 4.4 microg/mL, and 7.3 microg/mL respectively. After addition of verapamil (nonspecific P-glycoprotein inhibition), the IC(50)s on MDR-3T3 cells changed to 0.3 microg/mL, 0.7 microg/mL, and 1.5 microg/mL, respectively. The cellular uptake study of NBD-DOPE labeled nanoparticles by MDR-3T3 cells showed more cellular associated fluorescence than neutral liposomes (EPC/cholesterol). The cellular uptake was not affected by verapamil. Fluorescent nanoparticle-encapsulated 10-nonyl bromide acridine orange also demonstrated an enhanced uptake compared to neutral liposomes. The cellular uptake was increased after verapamil's addition. The cellular uptake of formulations with increased positive charges and the competition of free cationic lipid GL89 demonstrated that the positive charge of the particles enhanced the cellular uptake. In conclusion, although the cationic paclitaxel nanoparticle is susceptible to P-glycoprotein efflux, it is still a promising delivery system for paclitaxel, because of enhanced uptake, which resulted in significantly increased cytotoxicity.

Fatty acid metabolism in cystic fibrosis

Despite identification twenty years ago of the gene responsible for cystic fibrosis transmembrane conductance regulator (CFTR), the protein defective in cystic fibrosis (CF), research of this monogenetic disease has not provided an explanation for the divergent symptoms, and a treatment breakthrough is still awaited. This review discusses different aspects of disturbances in lipid metabolism seen in CF. These include increased release of arachidonic acid (AA) from cell membrane phospholipids and a low status of linoleic and docosahexaenoic acids. Recent research has explored more complicated lipid associations. Disturbances in annexins and ceramides might act in concert to explain the impact on inflammation and AA release. The connections to CFTR and between the disturbances in essential fatty acid metabolism are reviewed. The metabolic interactions, some of which might be compensating, possibly explain the difficulties in understanding the fatty acid disturbances in relation to different symptoms and their relation to the defective CFTR.

Dislipidemia relacionada à fibrose cística

Esse artigo tem por objetivo rever o conhecimento atual sobre a fisiopatologia, o diagnóstico e a abordagem da dislipidemia relacionada à fibrose cística (DFC). A pesquisa bibliográfica utilizou os bancos de dados Medline e Literatura Latino-Americana e do Caribe em Ciências da Saúde (1987-2007), selecionando os artigos mais relevantes sobre o tema. A DFC é caracterizada por hipertrigliceridemia e/ou hipocolesterolemia e deficiência de ácidos graxos essenciais. Seus principais fatores de risco são: insuficiência pancreática, dieta rica em carboidratos, hepatopatias, estado inflamatório e corticoterapia. Não existem recomendações específicas sobre a triagem, que habitualmente é realizada a partir do diagnóstico e, em intervalos regulares, com maior freqüência, nos indivíduos pertencentes aos grupos de risco. O tratamento inclui: dieta balanceada, reposição de micronutrientes, vitaminas e fibras, além de exercício físico regular de acordo com a tolerância individual. Na grande maioria dos casos, a hipertrigliceridemia da DFC não atinge valores que indiquem o uso de hipolipemiantes. Conclui-se que existem poucos trabalhos na literatura sobre a freqüência, etiologia e manejo da DFC. A recomendações preventivas e terapêuticas para a hipertrigliceridemia são extrapoladas de diretrizes para indivíduos sem fibrose cística. Mais pesquisas são necessárias para investigar a associação da deficiência de ácidos graxos essenciais com a fisiopatologia da fibrose cística. Como a hipertrigliceridemia é um importante fator de risco para doença arterial coronariana, estudos prospectivos irão contribuir para o melhor entendimento da história natural dessa complicação bem como definir maneiras de preveni-la e tratá-la.

Improved Oral Delivery of N-(4-Hydroxyphenyl)Retinamide with a Novel LYM-X-SORB Organized Lipid Complex

PURPOSE

Fenretinide [N-(4-hydroxyphenyl)retinamide (4-HPR)] is a cytotoxic retinoid that suffers from a wide interpatient variation in bioavailability when delivered orally in a corn oil capsule. The poor bioavailability of the capsule formulation may have limited responses in clinical trials, and the large capsules are not suitable for young children. To support the hypothesis that a novel organized lipid matrix, LYM-X-SORB, can increase the oral bioavailability of fenretinide, fenretinide in LYM-X-SORB matrix and in a powderized LYM-X-SORB formulation was delivered to mice.

EXPERIMENTAL DESIGN

Fenretinide was delivered orally to mice as the contents of the corn oil capsule, in LYM-X-SORB matrix (4-HPR/LYM-X-SORB matrix) or in a LYM-X-SORB matrix powderized with sugar and flour (4-HPR/LYM-X-SORB oral powder). Levels of 4-HPR, and its principal metabolite, N-(4-methoxyphenyl)retinamide, were assayed in plasma and tissues.

RESULTS

In a dose-responsive manner, from 120 to 360 mg/kg/d, delivery to mice of 4-HPR in LYM-X-SORB matrix, or as 4-HPR/LYM-X-SORB oral powder, increased 4-HPR plasma levels up to 4-fold (P<0.01) and increased tissue levels up to 7-fold (P<0.01) compared with similar doses of 4-HPR delivered using capsule contents. Metabolite [N-(4-methoxyphenyl)retinamide] levels mirrored 4-HPR levels. Two human neuroblastoma murine xenograft models showed increased survival (P<0.03), when treated with 4-HPR/LYM-X-SORB oral powder, confirming the bioactivity of the formulation.

CONCLUSIONS

4-HPR/LYM-X-SORB oral powder is a novel, oral drug delivery formulation, suitable for pediatric use, which warrants further development for the delivery of fenretinide in the treatment of cancer. A phase I clinical trial in pediatric neuroblastoma is in progress.

Serum phospholipid fatty acid profile and dietary intake in an adult Mediterranean population with cystic fibrosis

The relative importance of the usual diet in serum phospholipids in subjects with cystic fibrosis (CF) has been poorly studied. To compare the fatty acid profile in serum phospholipids from adult CF subjects with that of healthy subjects, and determine the role of the normal diet in this profile, we studied thirty-seven adult CF subjects with stable pulmonary disease and thirty-seven healthy controls matched for age, sex and nutritional status. A dietary questionnaire was obtained, anthropometric data were recorded, and the fatty acid profile measured by GLC. Compared with the controls, the percentages of myristic, palmitoleic and stearic acids and total MUFA were significantly higher in the CF group, and DHA, linoleic acid, total PUFA and n−6 fatty acids were significantly lower in the CF group. The CF subjects with worse pulmonary function and with pancreatic insufficiency had significantly lower levels of linoleic and n−6 fatty acids. The total energy intake was significantly higher in the CF subjects, although the energy distribution in the CF subjects and the controls was not different for the carbohydrates, lipids and proteins. No differences were detected in fat intake for MUFA (51 (sd 4) v. 52 (sd 4) %) or saturated fatty acids (33·5 (sd 5) v. 31·2 (sd 3·8) %), but the PUFA were slightly lower in the CF subjects (15·4 (sd 4·5) v. 17·4 (sd 4·2) %; P=0·02). The usual dietary intake of fatty acids by adult CF subjects does not appear to explain the difference in the fatty acid profile compared with controls. This suggests an abnormal fatty acid metabolism in CF subjects.

Oral calorie supplements for cystic fibrosis

BACKGROUND

Poor nutrition occurs frequently in people with cystic fibrosis (CF) and is associated with other adverse outcomes. Oral calorie supplements are used to increase total daily calorie intake and improve weight gain. However, they are expensive and there are concerns they may reduce the amount of food eaten and not improve overall energy intake.

OBJECTIVES

To establish whether in people with CF, oral calorie supplements: increase daily calorie intake; and improve overall nutritional intake, nutritional indices, lung function, survival and quality of life. To assess adverse effects associated with using these supplements.

SEARCH STRATEGY

We searched the Cochrane CF Trials Register comprising references from comprehensive electronic database searches, handsearches of relevant journals and abstract books of conference proceedings. We contacted companies marketing oral calorie supplements. Last search: October 2006.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing use of oral calorie supplements for at least one month to increase calorie intake with no specific intervention or additional nutritional advice in people with CF.

DATA COLLECTION AND ANALYSIS

We independently selected the included trials, assessed methodological quality and extracted data. We contacted the authors of included trials and for two trials obtained additional information.

MAIN RESULTS

Eighteen trials were identified and three, reporting results from 131 participants, were included. There were no significant differences between people receiving supplements or dietary advice alone for change in weight, height, body mass index, z score or other indices of nutrition or growth. Changes in weight (kg) at three, six and twelve months respectively were: WMD 0.32 (95% CI -0.09 to 0.72); WMD 0.47 (95% CI -0.07 to 1.02 ); and WMD 0.16 (-0.68 to 1.00). Total calorie intake was greater in people taking supplements at 12 months, WMD 265.70 (95% CI 42.94 to 488.46). There were no significant differences between the groups for anthropometric measures of body composition, lung function, gastrointestinal adverse effects or activity levels.

AUTHORS' CONCLUSIONS

Oral calorie supplements do not confer any additional benefit in the nutritional management of moderately malnourished children with CF over and above the use of dietary advice and monitoring alone. While nutritional supplements may be used, they should not be regarded as essential. Further randomised controlled trials are needed to establish the role of oral protein energy supplements for the short-term in people with CF and acute weight loss and also for the long-term nutritional management of adults with CF or advanced lung disease, or both.

An overview of monitoring and supplementation of omega 3 fatty acids in cystic fibrosis

Essential fatty acid deficiency has been increasingly reported in patients with cystic fibrosis. The purpose of this work is to critically summarize previous data on fatty acid status and omega3 supplementation in cystic fibrosis. Although the reported abnormalities differ from study to study, the two most consistent features appeared to be reduced circulating levels of linoleic acid and docosahexaenoic acid (DHA). On the assumption that the fatty acid composition of erythrocyte cell membranes may be similar to that of other organs, it seems appropriate to monitor the phospholipid profile from erythrocyte membranes together with circulating blood levels. Formulations containing widely variable DHA doses, ranging from 300 mg to 5 g per day, have been administered to patients with cystic fibrosis with discrepant outcomes. Randomized controlled trials are needed in order to draw firm conclusions on the therapeutic effect of omega3 fatty acid supplementation in cystic fibrosis.

Mechanisms of lipid malabsorption in Cystic Fibrosis: the impact of essential fatty acids deficiency

Transport mechanisms, whereby alimentary lipids are digested and packaged into small emulsion particles that enter intestinal cells to be translocated to the plasma in the form of chylomicrons, are impaired in cystic fibrosis. The purpose of this paper is to focus on defects that are related to intraluminal and intracellular events in this life-limiting genetic disorder. Specific evidence is presented to highlight the relationship between fat malabsorption and essential fatty acid deficiency commonly found in patients with cystic fibrosis that are often related to the genotype. Given the interdependency of pulmonary disease, pancreatic insufficiency and nutritional status, greater attention should be paid to the optimal correction of fat malabsorption and essential fatty acid deficiency in order to improve the quality of life and extend the life span of patients with cystic fibrosis.

Essential fatty acids and their derivatives

PURPOSE OF REVIEW

This review will address recent research in metabolism of essential fatty acids and their long chain derivatives. Our main focus will be the association between essential fatty acid status and various disease states, as well as the effects of supplementation with essential fatty acids or their derivatives on a number of clinical outcomes.

RECENT FINDINGS

There have been several papers over the last few years that show links between supplementation with fish oil (n-3 polyunsaturated fatty acids) and cardiovascular disease. Recent data suggest that the use of fish oil (containing n-3 fatty acids) in a variety of disorders such as cystic fibrosis, coronary disease and in the prevention of sudden death is beneficial. Several papers show reductions in systemic markers of inflammation. More widespread use of essential fatty acid derivatives in infant formula can certainly be questioned on the basis of the recent data. Fewer benefits are seen with ingestion of the essential fatty acids themselves, likely related to limited conversion to their long chain derivatives in humans.

SUMMARY

Derivatives of essential fatty acids have the potential to modify a number of disease states, either ingested in greater quantities in the diet, or taken as supplements in the form of fish oil.

Is there a case for n-3 fatty acid supplementation in cystic fibrosis?

PURPOSE OF REVIEW

This review evaluates our current knowledge on the association of fatty acid abnormalities in cystic fibrosis with the disease process, and makes a case for a well-designed clinical trial to evaluate the clinical efficacy of long chain n-3 fatty acids.

RECENT FINDINGS

It has long been known that cystic fibrosis patients exhibit fatty acid abnormalities, but these have not been well investigated in tissues affected by the disease. Recent studies have demonstrated that such tissues do indeed show abnormalities in the proportions of linoleic, arachidonic and docosahexaenoic acids, and have demonstrated alterations in fatty acid and phospholipid metabolism in cystic fibrosis. Work in other areas has identified novel anti-inflammatory actions of long chain n-3 fatty acids that might be relevant to cystic fibrosis. A recent systematic review of fish oil supplementation in cystic fibrosis did not allow firm conclusions to be drawn, but suggested that there may be some benefits.

SUMMARY

The restoration of abnormal fatty acid profiles may be beneficial in cystic fibrosis, but this approach has not been evaluated in studies with a suitable design to permit firm conclusions to be drawn. There is a need for a long-term randomized controlled study to evaluate the therapeutic benefit of fish oil supplementation in cystic fibrosis.

Circulating markers to assess nutritional therapy in cystic fibrosis

Cystic fibrosis (CF) is the most commonly occurring lethal autosomal recessive disorder. The gene defect causes defective sodium and chloride transport across epithelial cells of the respiratory, hepatobiliary, gastrointestinal and reproductive tracts, resulting in thick mucus secretions. In the respiratory tract, mucus traps bacteria, causing repeated lung infections, progressive bronchiectasis and eventual death due to respiratory failure. In the gastrointestinal tract, mucus prevents pancreatic enzymes reaching the gut, leading to nutrient malabsorption. Careful nutritional management has a dramatic effect on growth and survival rates in CF. Appropriate nutritional support includes pancreatic enzyme replacement therapy, a high-fat/high-energy diet and essential nutrient supplementation, specifically fat-soluble vitamins and essential fatty acids (EFA). Long-term studies are required to examine the effects of nutritional interventions on key clinical outcomes in CF, such as the rate of decline of lung function. The use of circulating markers to assess the influence of nutritional therapy allows short-term intervention studies to predict the potential for clinical improvements. This article provides an overview of the biomarkers useful in the prediction of the efficacy of nutritional therapy on improvements in quality and quantity of life in CF.

New lipids in enteral feeding

PURPOSE OF REVIEW

Lipid sources for enteral nutrition continue to be an exciting area of investigation. It is timely to review recent developments which have largely contributed to thrust enteral feeding into a new era.

RECENT FINDINGS

Although much more research needs to be done, there is a better understanding of the competitive relationships between n-6/n-3 fatty acids in conditions of metabolic and immune stress as well as in autoimmune and degenerative diseases. Although structured lipids are more completely absorbed and cleared, other more important clinical benefits need to be documented before they can be considered cost-effective. Immune enhancing formulas are the subject of controversy and some have been shown to be more effective than others. Enteral formulations with short-chain fatty acids are promising but more experimental work on the normal, and the sick colon is needed. Finally, there are a few isolated studies suggesting that enteral feeding with liposomes and with lipolytic products may have advantages when the digestive phase needs to be circumvented. The era of nutrigenomics, in which the effect of specific lipids on genes and proteins is being explored, is with us. We can look forward to nutrigenetics when the effect of genetic variation on the interaction between diet and disease will guide our practice.

SUMMARY

Clinicians already have access to lipid sources and formulations which allow them to individualize enteral feeding programs. More clinical and technological research needs to be carried out, however, before products can be tailored to produce optimal effects in specific conditions.

Vitamin A uptake from foods

PURPOSE OF REVIEW

To review our current understanding of vitamin A uptake from foods.

RECENT FINDINGS

There are advancements in understanding the molecular processes involved in vitamin A uptake and the regulation of these processes. A number of genes involved in vitamin A transport and metabolism have been recently identified. The identification of mutations in human genes and targeted disruption of mouse genes have provided further insight as to how these genes contribute to meeting nutritional needs.

SUMMARY

The rate limiting steps in the lymphatic absorption of vitamin A involve intracellular processing of vitamin A within the enterocyte. The key steps appear to be related to chylomicron formation and secretion and are closely coupled with fat absorption. The genes encoding serum retinol binding protein, cellular retinol binding protein I and cellular retinol binding protein II have been disrupted by homologous recombination in mice. Studies of these knockout mice indicate that extrahepatic uptake of postprandial vitamin A may play a particularly important role in the maternal-offspring transfer of vitamin A. Further studies of the transfer of maternal dietary vitamin A have important implications for assessing the upper limits of maternal vitamin A supplementation.

Oral protein calorie supplementation for children with chronic disease

BACKGROUND

Growth failure and poor nutritional status are common features in children with chronic diseases due to reduced appetite, malabsorption and increased nutritional requirements associated with some diseases. The provision of oral protein calorie supplements is one of a number of interventions used to improve nutritional status in these children. The use of these products, which are expensive, may be associated with a number of adverse effects, for example, they may effect development of normal eating behaviour patterns or lead to unpleasant symptoms such as vomiting and diarrhoea.

OBJECTIVES

To examine the evidence that in children with chronic disease, oral protein calorie supplements alter daily nutrient intake, nutritional indices, survival and quality of life and are associated with adverse effects, for example diarrhoea, vomiting, reduced appetite, glucose intolerance, bloating and eating behaviour problems.

SEARCH STRATEGY

All publications describing RCTs of the use of oral protein calorie supplements in children with chronic diseases were identified through comprehensive electronic database searches, handsearching relevant journals and handsearching abstract books of conference proceedings. The companies which market oral protein calorie supplements were also contacted.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials comparing use of oral protein calorie supplements for at least one month to increase calorie intake with existing conventional therapy, which may include nutritional advice on how to improve nutritional intake from food or no specific intervention, in children with chronic disease.

DATA COLLECTION AND ANALYSIS

The following outcomes were assessed: indices of nutrition and growth, anthropometric measures of body composition, calorie and nutrient intake (total, from oral protein calorie supplements and from food), eating behaviour, compliance, quality of life, specific adverse effects and disease severity scores, and mortality.

MAIN RESULTS

Three trials have been identified as being suitable for inclusion in the review and we are awaiting further data from one of these trials. All of these trials were carried out in children with cystic fibrosis. Few statistical differences could be found between the treatment and control groups apart from change in total fat intake at three months (weighted mean difference 69.20 [95% CI 11.05, 127.35]). However, this was based on the results of only one, small study. No trials have been identified which assess the effectiveness of oral protein calorie supplements in children with other chronic diseases.

REVIEWER'S CONCLUSIONS

Oral protein calorie supplements are widely used to improve the nutritional status of children with a number of chronic diseases. We have only been able to identify a small number of trials assessing these products in children with cystic fibrosis and have been unable to draw any conclusions based on the limited data extracted from these. We therefore recommend that a series of large, randomised controlled trials are undertaken investigating the use of these products in children with different chronic diseases. Until further data are available, we would suggest that these products are only used with caution.

Oral calorie supplements for cystic fibrosis

BACKGROUND

Poor nutrition occurs frequently in children and adults with cystic fibrosis and is associated with a number of other adverse outcomes. Oral calorie supplements are used to try and increase total daily calorie intake and improve weight gain. However, they are expensive and there are concerns that they may lead to a reduction in the amount of food eaten and no overall improvement in energy intake.

OBJECTIVES

To examine the evidence that in patients with cystic fibrosis, oral calorie supplements increase daily calorie intake, improve overall nutritional intake, nutritional indices, lung function, survival and quality of life. To assess possible adverse effects associated with use of oral calorie supplements.

SEARCH STRATEGY

The Cochrane Cystic Fibrosis and Genetic Disorders Group specialist trials register which comprises references identified from comprehensive electronic database searches, handsearching relevant journals and handsearching abstract books of conference proceedings. The companies which market oral calorie supplements were also contacted. Date of the most recent search of the Group's specialised register: November 1999.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials comparing use of oral calorie supplements for at least one month to increase calorie intake with no specific intervention or additional nutritional advice in patients with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

The following outcomes were assessed: indices of nutrition and growth, anthropometric measures of body composition, calorie intake (total, from oral calorie supplements and from food), nutrient intake, eating behaviour, quality of life, specific adverse effects, lung function and mortality.

MAIN RESULTS

Two trials which reported results from a total of 29 patients were suitable for inclusion in the review. From the data provided in the published reports only one item (change in weight) could be extracted from one trial for inclusion in the review. This showed no difference between intervention and comparison group.

REVIEWER'S CONCLUSIONS

Oral calorie supplements are very widely used around the world in an attempt to improve nutritional status in patients with cystic fibrosis, at some considerable cost. It is therefore very disappointing that their effectiveness has not been assessed by adequate clinical trials. No conclusions can be made about the use of oral calorie supplements in cystic fibrosis from the information currently available and clinicians must balance potential benefits against possible adverse effects of treatment in making decisions about individual patients. This systematic review has clearly identified the need for a well designed, adequately-powered, multicentre, randomised controlled trial assessing the effectiveness and possible adverse effects of oral calorie supplements in cystic fibrosis.