Nutrition and Lung Disease in Cystic Fibrosis

Update on advances in cystic fibrosis towards a cure and implications for primary care clinicians

During the past quarter century, the diagnosis and treatment of cystic fibrosis (CF) have been transformed by molecular sciences that initiated a new era with discovery of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The knowledge gained from that breakthrough has had dramatic clinical impact. Although once a diagnostic dilemma with long delays, preventable deaths, and irreversible pathology, CF can now be routinely diagnosed shortly after birth through newborn screening programs. This strategy of pre-symptomatic identification has eliminated the common diagnostic "odyssey" that was a failure of the healthcare delivery system causing psychologically traumatic experiences for parents. Therapeutic advances of many kinds have culminated in CFTR modulator treatment that can reduce the effects of or even correct the molecular defect in the chloride channel -the basic cause of CF. This astonishing advance has transformed CF care as described fully herein. Despite this impressive progress, there are challenges and controversies in the delivery of care. Issues include how best to achieve high sensitivity newborn screening with acceptable specificity; what course of action is appropriate for children who are identified through the unavoidable incidental findings of screening tests (CFSPID/CRMS cases and heterozygote carriers); how best to ensure genetic counseling; when to initiate the very expensive but life-saving CFTR modulator drugs; how to identify new CFTR modulator drugs for patients with non-responsive CFTR variants; how to adjust other therapeutic modalities; and how to best partner with primary care clinicians. Progress always brings new challenges, and this has been evident worldwide for CF. Consequently, this article summarizes the major advances of recent years along with controversies and describes their implications with an international perspective.

Food insecurity screening and local food access: Contributions to nutritional outcomes among children and adults with cystic fibrosis in the United States

BACKGROUND

As the nutritional status of people with CF (PwCF) is associated with their socioeconomic status, it is important to understand factors related to food security and food access that play a role in the nutritional outcomes of this population. We assessed the contributions of CF program-level food insecurity screening practices and area-level food access for nutritional outcomes among PwCF.

METHODS

We conducted a cross-sectional analysis of 2019 data from the U.S. CF Patient Registry (CFFPR), linked to survey data on CF program-level food insecurity screening and 2019 patient zip code-level food access. Pediatric and adult populations were analyzed separately. Nutritional outcomes were assessed with annualized BMI percentiles (CDC charts) for children and BMI (kg/m2) for adults, with underweight status defined as BMIp <10% for children and BMI <18.5 kg/m2 for adults, and overweight or obese status defined as BMIp >85% for children and BMI >25 kg/m2 for adults. Analyses were adjusted for patient sociodemographic and clinical characteristics.

RESULTS

The study population included 11,971 pediatric and 14,817 adult PwCF. A total of 137 CF programs responded to the survey, representing 71% of the pediatric sample and 45% of the CFFPR adult sample. The joint models of nutritional status as a function of both program-level food insecurity screening and area-level food access produced the following findings. Among children with CF, screening at every visit vs less frequently was associated with 39% lower odds of being underweight (OR 0.61, p = 0.019), and the effect remained the same and statistically significant after adjusting for all covariates (aOR 0.61, p = 0.047). Residence in a food desert was associated both with higher odds of being underweight (OR 1.66, p = 0.036; aOR 1.58, p = 0.008) and with lower BMIp (-4.81%, p = 0.004; adjusted -3.73%, p = 0.014). Among adults with CF, screening in writing vs verbally was associated with higher odds of being overweight (OR 1.22, p = 0.028; aOR 1.36, p = 0.002) and higher BMI (adjusted 0.43 kg/m2, p = 0.032). Residence in a food desert was associated with higher odds of being underweight (OR 1.48, p = 0.025).

CONCLUSIONS

Food insecurity screening and local food access are independent predictors of nutritional status among PwCF. More frequent screening is associated with less underweight among children with CF, whereas screening in writing (vs verbally) is associated with higher BMI among adults. Limited food access is associated with higher odds of being underweight in both children and adults with CF, and additionally with lower BMI among children with CF. Study results highlight the need for standardized, evidence-based food insecurity screening across CF care programs and for equitable food access to optimize the nutritional outcomes of PwCF.

Treatable traits and challenges in the clinical management of non-tuberculous mycobacteria lung disease in people with cystic fibrosis

INTRODUCTION

Over the last ten years an increasing prevalence and incidence of non-tuberculous mycobacteria (NTM) has been reported among patients with cystic fibrosis (CF) Viviani (J Cyst Fibros, 15(5):619-623, 2016). NTM pulmonary disease has been associated with negative clinical outcomes and often requires pharmacological treatment. Although specific guidelines help clinicians in the process of diagnosis and clinical management, the focus on the multidimensional assessment of concomitant problems is still scarce.

MAIN BODY

This review aims to identify the treatable traits of NTM pulmonary disease in people with CF and discuss the importance of a multidisciplinary approach in order to detect and manage all the clinical and behavioral aspects of the disease. The multidisciplinary complexity of NTM pulmonary disease in CF requires careful management of respiratory and extra-respiratory, including control of comorbidities, drug interactions and behavioral factors as adherence to therapies.

CONCLUSIONS

The treatable trait strategy can help to optimize clinical management through systematic assessment of all the aspects of the disease, providing a holistic treatment for such a multi-systemic and complex condition.

What do people with cystic fibrosis eat? Diet quality, macronutrient and micronutrient intakes (compared to recommended guidelines) in adults with cystic fibrosis-A systematic review

BACKGROUND

Treatment advancements have improved life expectancy and nutritional status of people with cystic fibrosis (CF). Alongside reductions in malnutrition, incidences of overweight, obesity and risk factors for diet-related chronic diseases have increased in recent years. This study aimed to synthesise the available literature on diet quality, macronutrient and micronutrient intakes compared to the recommended guidelines in adults with CF, an essential step in deducing the optimal dietary pattern and intakes for CF adults.

METHODS

A systematic search of five electronic databases from inception until April 2023 was conducted using keywords related to CF, diet quality and nutrient intakes.

RESULTS

Twenty-one studies were included comprising 18 cross-sectional, one cohort and two case control studies, reporting data from 724 adults with CF. Energy and / or macronutrient intake data was reported across 17 cohorts, eight studies provided micronutrients data, and diet quality was determined for four CF cohorts by using a diet quality score, and / or categorising food intake into servings per day for food groups and comparing findings to national dietary guidelines. Although energy intake recommendations were met, and most micronutrient requirements were achieved through supplementation, total energy intake from fat was above recommendations and diet quality was poor.

CONCLUSION

This is the first systematic review comprehensively evaluating literature on dietary intakes of adults with CF. Energy-dense, nutrient-poor foods contribute to intakes which pose risk in developing diet-related chronic diseases. Revision of dietary guidelines and practice change in CF nutritional therapy is warranted to optimise nutrition and health outcomes.

What is the Perceived Role of the Dietitian Amongst People with Cystic Fibrosis? Results of an International survey

Cystic fibrosis (CF) is a chronic condition requiring continued input from the CF dietitian as an integral part of the CF multidisciplinary team. In recent years, the longer life expectancy experienced by people with CF (PwCF) means that nutrition advice and therapy are evolving from a focus on nutrition support to prevention and management of comorbidities. Little has been reported regarding the perceived role of the CF dietitian amongst PwCF. We report the responses to 11 questions that were part of a larger international survey distributed to members of national CF charities in 2018-2019. These questions evaluated PwCFs' perspectives on (i) the importance of the CF diet, (ii) how often PwCF obtain dietary/nutritional advice from their dietitian, (iii) the perceived reliability of information given by the dietitian, (iv) other sources of CF information and their perceived reliability, and (v) how CF nutrition/diet, as well as CF-related diabetes, ranked as research priorities. There were 295 respondents from 13 countries. Almost half of the respondents (46.8%) contacted their CF dietitian on a frequent/more regular basis, compared to medical/scientific journals/medical/scientific search engines. The CF dietitian was considered a reliable source of information, as 84% of the respondents indicated that the information provided was very/generally reliable. At a time when CF care and expectations are changing rapidly, PwCF are in need of trusted and reliable information to make positive changes in lifestyle and habits. Dietitians working with PwCF should appreciate the pivotal and valued role they perform as purveyors of robust evidence-based information to this chronic disease population.

Diet quality in cystic fibrosis – associations with patient reported outcome measures and enablers and barriers to eating a healthy diet: A protocol paper for a mixed methods study

Background: People with cystic fibrosis (PWCF) have increased energy requirements. However, in recent years concerns have emerged regarding the ‘cystic fibrosis (CF) diet’ in terms of reliance on energy-dense, nutrient poor foods, which tend to be higher in saturated fat, sugar, and salt. These foods lack essential nutrients and are aetiologically linked with diet-related chronic diseases. The aim is to explore habitual dietary intakes in PWCF and (i) assess adherence to CF dietary guidelines and population specific healthy eating guidelines; (ii) derive a diet quality score and the inflammatory potential for the average diet consumed by PWCF and assess associations with patient reported outcome measures; (iii) assess drivers for current consumption patterns and enablers and barriers to eating a healthy diet. Methods: The aim is to recruit between 100-180 PWCF. A mixed methods study will be performed. Using three-day food diaries and food frequency questionnaires, aims (i) and (ii) will be addressed. The Dietary Approaches to Stop Hypertension (DASH) score and Healthy Eating Index-International (HEI-I) will derive diet quality scores. The Dietary Inflammatory Index (DII®) will ascertain inflammatory potential of the diet. Validated questionnaires will be used to report health related quality of life measures. Online focus groups and semi-structured interview with PWCF will address aim (iii). Conclusions: It is timely to revise dietary priorities and targets for CF. However, a greater understanding of what adults with CF currently consume and what they require in terms of nutrition and dietary guidance into the future is needed. In doing so, this research will help to clarify nutrition priorities and simplify the dietary aspects of CF treatment, thereby supporting adherence.

Association of Body Mass Index With Clinical Outcomes in Patients With Cystic Fibrosis: A Systematic Review and Meta-analysis

IMPORTANCE

The prevalence of overweight (body mass index [BMI] = 25-29.9 [calculated as weight in kilograms divided by height in meters squared]) and obesity (BMI ≥30) is increasing among patients with cystic fibrosis (CF). However, it is unclear whether there is a benefit associated with increasing weight compared with the reference range (ie, normal) in CF.

OBJECTIVE

To evaluate the association of altered BMI or body composition and clinical outcomes in patients with CF.

DATA SOURCES

For this systematic review and meta-analysis, the literature search was conducted November 2, 2020, of 3 databases: MEDLINE (via PubMed), Embase, and Cochrane Central Register of Controlled Trials.

STUDY SELECTION

Patients older than 2 years diagnosed with CF with altered body composition or BMI were compared with patients having the measured parameters within the reference ranges. Records were selected by title, abstract, and full text; disagreements were resolved by consensus. Cohort studies and conference abstracts were eligible; articles with no original data and case reports were excluded.

DATA EXTRACTION AND SYNTHESIS

Two authors independently extracted data, which were validated by a third author. Studies containing insufficient poolable numerical data were included in the qualitative analysis. A random-effects model was applied in all analyses.

MAIN OUTCOMES AND MEASURES

Pulmonary function, exocrine pancreatic insufficiency (PI), and CF-related diabetes (CFRD) were investigated as primary outcomes. Odds ratios (ORs) or weighted mean differences (WMDs) with 95% CIs were calculated. The hypothesis was formulated before data collection.

RESULTS

Of 10 524 records identified, 61 met the selection criteria and were included in the qualitative analysis. Of these, 17 studies were included in the quantitative synthesis. Altogether, 9114 patients were included in the systematic review and meta-analysis. Overweight (WMD, -8.36%; 95% CI, -12.74% to -3.97%) and obesity (WMD, -12.06%; 95% CI, -23.91% to -0.22%) were associated with higher forced expiratory volume in the first second of expiration compared with normal weight. The odds for CFRD and PI were more likely in patients of normal weight (OR, 1.49; 95% CI, 1.10 to 2.00) than in those who were overweight (OR, 4.40; 95% CI, 3.00 to 6.45). High heterogeneity was shown in the analysis of pulmonary function (I2 = 46.7%-85.9%).

CONCLUSIONS AND RELEVANCE

The findings of this systematic review and meta-analysis suggest that the currently recommended target BMI in patients with CF should be reconsidered. Studies with long-term follow-up are necessary to assess the possible adverse effects of higher BMI or higher fat mass in patients with CF.

Deprivation of Dietary Fiber Enhances Susceptibility of Piglets to Lung Immune Stress

Growing evidence suggests that dietary fiber enhances short-chain fatty acid (SCFA) producing gut microbes, improving lung immunity against invading pathogens via the gut–lung axis. This study investigated the effects of dietary fiber on lung immune stress after challenge with complete Freund's adjuvant (CFA) containing killed Mycobacterium tuberculosis. Thirty-six healthy hybrid Duroc, Landrace, and Yorkshire male piglets (9.7 ± 1.07 kg, 35 ± 3 days) were randomly fed a low fiber (LF) diet formulated with semipurified corn starch, soy protein concentrate, and fishmeal or a high fiber (HF) diet composed of 1,000 g LF diet plus 20 g inulin, and 100 g cellulose. Piglets were housed individually in the metabolism cages with eighteen replicates per group, with one pig per cage. All the piglets received similar levels of digestible energy and lysine and had similar weight gain. After dietary treatment for 28 days, nine piglets per group were intravenously administered CFA (0.4 mg/kg) or an equivalent amount of sterile saline in a 2 × 2 factorial arrangement. In piglets fed the LF diet, CFA caused lung damage and elevated serum C-reactive protein and relative mRNA expression of genes related to lung inflammation (NLRP3, Casp1, ASC, IL1β, IL18, Bax). Compared with the LF diet, the HF diet increased bacterial diversity and Deferribacteres (p = 0.01) in the phylum level and unidentified_Ruminococcaceae (p = 0.03) and Catenisphaera (p < 0.01) in the genus level. The HF diet improved increased short-chain fatty acids in feces, blood, cecal, and colonic digesta; reduced lung damage; and promoted lung recovery. Overall, dietary fiber deprivation enhanced the risk of piglets to lung immune stress, demonstrating the importance of dietary fiber in gut–lung health.

The determinants of survival among adults with cystic fibrosis-a cohort study

BACKGROUND

Cystic fibrosis (CF) is one of the most common autosomal recessive diseases. Factors contributing to disease exacerbations and survival rate of CF patients are type of mutation in the CFTR gene, poor nutritional status, lung failure, and infection development by Pseudomonas aeruginosa. The study aimed to evaluate the relationship between the severity of mutation, nutritional status, lung function, and Pseudomonas aeruginosa prevalence and survival rate in adult patients with cystic fibrosis.

METHODS

A study of 124 (68 ♀ and 56 ♂) adults with CF aged 18-51 years were evaluated for (a) type of mutation in the CFTR gene, (b) nutritional status (BMI), (c) lung function (FEV₁%), and (d) Pseudomonas aeruginosa prevalence. For statistical calculations, Kaplan-Meier analysis of survival, chi-squared test for multiple samples, and logistic regression were used.

RESULTS

The type of mutation (χ² = 12.73, df = 3, p = 0.005), FEV₁% (χ² = 15.20, df = 2, p = 0.0005), Pseudomonas aeruginosa prevalence (χ² = 11.48, df = 3, p = 0.009), and BMI (χ² = 31.08, df = 4, p < 0.000) significantly differentiated the probability of survival of patients with CF. The shortest life expectancy was observed in patients with a severe type of mutation on both alleles, FEV₁% < 40, subjects in whom Pseudomonas culture was extensively drug-resistant or pandrug-resistant, and patients whose BMI was lower than 18.5 kg/m². The period from 30 to 40 years of age was the most critical in CF adults' lifespan. The risk of adults with CF death doubled with Pseudomonas aeruginosa prevalence (OR = 2.06, 95% CI 1.29; 2.28) and eightfold when the bacteria acquired antibiotic resistance (OR = 8.11, 95% CI 1.67; 38.15).

CONCLUSIONS

All factors included in the study were significantly related to the survival rate of patients with cystic fibrosis.

Factors Influencing Lung Function in Patients with Cystic Fibrosis in Western Romania

PURPOSE

The aim of this cross-sectional study was to identify the major factors influencing pulmonary function in CF patients from western side of Romania.

PATIENTS AND METHODS

The study enrolled 51 patients with CF between the ages of 6 and 27.8 years who were monitored at regular visits to the National Cystic Fibrosis Centre and Pius Branzeu County Hospital in Timisoara, Romania, over a period of 2 years. The relationships between lung function, as measured by forced expiratory volume in 1 s (FEV1), with patient age, sex, body mass index (BMI), pancreatic insufficiency (PI), microbial infection, CF-related diabetes (CFRD), CF-associated liver disease (CFLD), and physical activity <30 min/day, were evaluated by multivariate regression analysis.

RESULTS

The results showed that FEV1 was 0.32% higher for each increase in percentile of BMI (95% confidence interval: 0.034-0.619). In addition, mean FEV1 was 1.52% lower with every year rise of age. PI and female sex increased the risk of impaired lung function (FEV1 <60%). The factors most closely correlated with pulmonary function in pediatric CF patients were current age (negative) and BMI (positive).

CONCLUSION

The findings of this study, in combination with what is known from other studies in CF, suggest that a better nutritional status and infection prophylaxis should be part of a comprehensive clinical management strategy for pediatric CF in Romania.

Body composition and lung function in adults with Cystic Fibrosis

The study aimed to assess: (1) differences in nutritional status and lung function between CF patients and the control group; (2) differences in body composition and lung function between groups of patients with CF designated by type of mutation; (3) the relationship between lung function and body composition in CF patients.

We studied 37 CF patients aged 19 to 51 years, and 41 healthy non-CF volunteers. Nutritional status was evaluated based on the BMI and the bioelectrical impedance analysis. The lung function was described by FEV1%. CF patients were classified according to the CFTR genotype based on five classes of mutations. BMI were lower in CF patients compared to reference group (women: Z = 3.76, p <0.001, men: Z = 3.06, p = 0.002). CF patients had a lower mean content of particular body components, as well as FEV1% values. BMI differed significantly depending on the type of mutation in females (H = 10.33, p = 0.006) and males (H = 8.26, p = 0.016). The lowest values of BMI were observed in the group of patients with severe types of mutations. Also, variables describing body composition were statistically significantly lower in patients with a severe type of mutations. The CFTR gene mutation type statistically significantly differentiated FEV1% (H = 23.22, p <0.000). The results of the logistic regression analysis showed that the likelihood of dropping FEV1% below the norm was twice as high in undernourished females and males. To assess the nutritional status of CF patients, more informative methods describing the proportions of body components are required.

Exercise Physiology Across the Lifespan in Cystic Fibrosis

Cystic fibrosis (CF), a severe life-limiting disease, is associated with multi-organ pathologies that contribute to a reduced exercise capacity. At present, the impact of, and interaction between, disease progression and other age-related physiological changes in CF on exercise capacity from child- to adult-hood is poorly understood. Indeed, the influences of disease progression and aging are inherently linked, leading to increasingly complex interactions. Thus, when interpreting age-related differences in exercise tolerance and devising exercise-based therapies for those with CF, it is critical to consider age-specific factors. Specifically, changes in lung function, chronic airway colonization by increasingly pathogenic and drug-resistant bacteria, the frequency and severity of pulmonary exacerbations, endocrine comorbidities, nutrition-related factors, and CFTR (cystic fibrosis transmembrane conductance regulator protein) modulator therapy, duration, and age of onset are important to consider. Accounting for how these factors ultimately influence the ability to exercise is central to understanding exercise impairments in individuals with CF, especially as the expected lifespan with CF continues to increase with advancements in therapies. Further studies are required that account for these factors and the changing landscape of CF in order to better understand how the evolution of CF disease impacts exercise (in)tolerance across the lifespan and thereby identify appropriate intervention targets and strategies.

Impact of cystic fibrosis on birthweight: a population based study of children in Denmark and Wales

BACKGROUND

Poor growth during infancy and childhood is a characteristic feature of cystic fibrosis (CF). However, the impact of CF on intrauterine growth is unclear. We studied the effect of CF on birth weight in Denmark and Wales, and assessed whether any associations are due to differences in gestational age at birth.

METHODS

We conducted national registry linkage studies in two countries, using data for 2.2 million singletons born in Denmark (between 1980 and 2010) and Wales (between 1998 and 2015). We used hospital inpatient and outpatient data to identify 852 children with CF. Using causal mediation methods, we estimated the direct and indirect (via gestational age) effect of CF on birth weight after adjustment for sex, parity and socioeconomic background. We tested the robustness of our results by adjusting for additional factors such as maternal smoking during pregnancy in subpopulations where these data were available.

RESULTS

Babies with CF were more likely to be born preterm and with low birth weight than babies with no CF (12.7% vs 5% and 9.4% vs 5.8% preterm; 11.9% vs 4.2% and 11% vs 5.4% low birth weight in Denmark and Wales, respectively). Using causal mediation methods, the total effect of CF on birth weight was estimated to be -178.8 g (95% CI -225.43 to -134.47 g) in the Danish population and -210.08 g (95% CI -281.97 to -141.5 g) in the Welsh population. About 40% of this effect of CF on birth weight was mediated through gestational age.

CONCLUSIONS

CF significantly impacts on intrauterine growth and leads to lower birth weight in babies with CF, which is only partially explained by shorter gestation.

Effect of antiretroviral therapy on longitudinal lung function trends in older children and adolescents with HIV-infection

Introduction

Chronic respiratory disease is a common cause of morbidity in children with HIV infection. We investigated longitudinal lung function trends among HIV-infected children, to describe the evolution of lung disease and assess the effect of anti-retroviral therapy (ART).

Methods

Prospective follow-up of two cohorts of HIV-infected children, aged 6 to 16 years, in Harare, Zimbabwe; one group were ART-naïve at enrolment, the other established on ART for a median of 4.7-years. Standardised spirometric assessments were repeated over a 2-year follow-up period. Forced expiratory volume (FEV₁) and forced vital capacity (FVC) were expressed as Global Lung Initiative defined z-scores (FEV₁z and FVCz). Linear mixed-effects regression modelling of lung function was performed, with co-variate parameters evaluated by likelihood ratio comparison.

Results

We included 271 ART-naïve and 197 ART-established children (median age 11 years in both groups) incorporating 1144 spirometric assessments. Changes in FEV₁ and FVC were associated with age at ART initiation and body mass index for both cohorts. Our models estimate that ART initiation earlier in life could prevent a deterioration of 0.04 FVCz/year. In the ART-naïve cohort, likelihood ratio comparison suggested an improvement in 0.09 FVCz/year during the two years following treatment initiation, but no evidence for this among participants established on ART.

Conclusion

Early ART initiation and improved nutrition are positively associated with lung function and are important modifiable factors. An initial improvement in lung growth was seen in the first 2-years following ART initiation, although this did not appear to be sustained beyond this timeframe.

A Survey Identifying Nutritional Needs in a Contemporary Adult Cystic Fibrosis Cohort

Background

Cystic fibrosis (CF) is a disease in which nutritional barriers are diverse and common, with malnutrition greatly influencing pulmonary trajectory and overall outcomes. Despite this, the most effective methods to optimize CF nutrition are unknown, and literature describing patients’ perspectives on their specific nutritional needs is lacking, particularly in the modern era of CF care. This study aimed to identify the most important nutritional needs and desired health-improvement resources in a contemporary adult CF cohort.

Methods

A 14-question investigator-designed survey addressing nutrition concerns, preferred health-improvement resources, and dietary/exercise routines was administered to CF adults. Clinical characteristics and survey responses are presented with descriptive statistics, and responses compared by body mass index (BMI) category (< 18.5 kg/m²; 18.5–24.99 kg/m²; 25–29.99 kg/m²; ≥30 kg/m²), gender, and socioeconomic status using Chi square or Fisher’s Exact testing.

Results

Of 66 total patients, nine (13.6%) were underweight (BMI < 18.5 kg/m²), while 19 (28.8%) were overweight or obese (BMI ≥ 25 kg/m²). In the overall cohort, the most common primary concern was preventing weight loss [in 20/66 patients (30.3%)], but there were significant differences by BMI (p < 0.001), with the most common concern in the overweight subgroup being preventing weight gain. Fifteen (46.9%) men (BMI mean 20.7, range 16.4–29.2 kg/m²) listed preventing weight loss as the primary concern, compared to only 5 (14.7%) women (BMI mean 18.4, range 16.2–19.9 kg/m²), representing a trend toward a difference in primary concerns by gender (p = 0.066).

The most commonly desired health-improvement resource was online CF nutrition and fitness information, found in 26 patients (39.4%) in the overall cohort, without significant differences by BMI (p = 0.814) or gender (p = 0.199). Financial assistance was the preferred resource in 17 (26.2%), without differences by socioeconomic status (p = 0.367).

Conclusions

We identified a wide variety of nutritional needs in CF adults, including a high prevalence of overweight status, many patients desiring weight loss, and many seeking financial resources. Our findings support the individualization of modern-day CF nutrition programs and development of online resources, in an effort to address the heterogeneous barriers that exist in the contemporary CF population and improve outcomes in patients with the disease.

Electronic supplementary material

The online version of this article (10.1186/s40795-018-0266-3) contains supplementary material, which is available to authorized users.

THE USE OF ULTRASONOGRAPHY TO EVALUATE MUSCLE THICKNESS AND SUBCUTANEOUS FAT IN CHILDREN AND ADOLESCENTS WITH CYSTIC FIBROSIS

Objective:

To compare muscle thickness and subcutaneous fat in cystic fibrosis (CF) patients and healthy controls using ultrasonography (US), and to correlate US findings with nutritional, clinical and functional variables.

Methods:

Patients aged 6 to 18 years old with a diagnosis of CF and healthy controls were included. Participants underwent anthropometric measurements, an ultrasonographic evaluation of muscle thickness and subcutaneous fat in the triceps, quadriceps, and gastrocnemius regions, and skinfold thickness measurements. Body fat percentage was estimated using skinfold measurement. Subjects with CF also underwent a pulmonary function assessment using spirometry.

Results:

We studied 39 CF patients and 45 controls. Alower body mass index was observed in CF patients (p=0.011). Body composition and muscle thickness were similar between the groups. Only calf (p=0.023) circumference and femur diameter (p<0.001) were lower in CF patients. Although there were no significant between-group differences in the comparison of US measurements of subcutaneous fat, CF patients exhibited decreased skinfold thickness in the triceps (p=0.031) and quadriceps (p=0.019). Moreover, there were weak and moderate correlations of US quadricep thickness with forced vital capacity (FVC) and lean mass, respectively. Moderate correlations of the triceps, quadriceps and gastrocnemius between US subcutaneous fat and skinfold measurements were found.

Conclusions:

Patients with CF presented a reduction in subcutaneous fat content. Muscle thickness correlated with FVC and nutritional parameters. In addition, US findings correlated positively with skinfold measurements.

Factors associated with malnutrition in adolescent and adult patients with cystic fibrosis

OBJECTIVE

To determine the prevalence of malnutrition in patients attending an adult cystic fibrosis (CF) program and to investigate the associations of malnutrition with the clinical characteristics of those patients.

METHODS

This was a cross-sectional study involving patients with clinically stable CF patients (16 years of age or older). The patients underwent clinical assessment, nutritional assessments, pulmonary function tests, and pancreatic function assessment. They also completed a questionnaire regarding diet compliance. On the basis of their nutritional status, the patients were classified divided into three groups: adequate nutrition; at nutritional risk; and malnutrition.

RESULTS

The study has included 73 patients (mean age, 25.6 ± 7.3 years), 40 of whom (54.8%) were female. The mean body mass index was 21.0 ± 3.0 kg/m2 and the mean FEV1 was 59.7 ± 30.6% of predicted. In this sample of patients, 32 (43.8%), 23 (31.5%), and 18 (24.7%) of the patients were allocated to the adequate nutrition, nutritional risk, and malnutrition groups, respectively. The logistic regression analysis identified three independent factors associated with the risk of malnutrition: Shwachman-Kulczycki score, percent predicted FEV1; and age.

CONCLUSIONS

Malnutrition remains a common complication in adolescents and adults with CF, despite dietary advice. Malnutrition is associated with age, clinical severity, and lung function impairment.

Accrual of Bone Mass in Children and Adolescents With Cystic Fibrosis

CONTEXT

Low bone density is a complication of cystic fibrosis (CF).

HYPOTHESIS

Accrual of bone mass is most impaired in the sickest children, as judged by nutritional status and pulmonary function.

DESIGN

Retrospective analysis of correlation between lumbar spine bone mineral density (BMD), body mass index (BMI), and forced expiratory volume in 1 second (FEV1) z scores in children and adolescents with CF.

SETTING

Pediatric hospital specialist CF service.

PATIENTS

Sixty participants aged 5.9 to 18.8 years (24 female) with confirmed CF.

INTERVENTIONS

Lumbar spine BMD, BMI, and FEV1 z scores measured at first BMD scan; 40 participants had sequential scans. Change in L1-L4 z scores over time was used as a measure of bone accrual, and BMI as a measure of nutritional status.

OUTCOME MEASURES

Correlations between lumbar spine BMD, BMI, and FEV1 z scores.

RESULTS

Mean BMI and BMD z scores were strongly correlated at the initial scan (P < 0.0001), suggesting that nutritional status is a major determinant of BMD. In the sequential scan at a mean age of 16.1 years, height centile was maintained, indicating normal linear growth. Changes in BMI and BMD z scores were positively correlated (P = 0.001), indicating that patients failing to gain weight appropriately with growth were also failing to acquire bone normally. Change in FEV1 z score was correlated with change in both BMD (P < 0.0001) and BMI z scores (P = 0.02).

CONCLUSION

Although young people with CF may be maintaining normal growth in height, bone accrual is impaired in those with the poorest nutritional status and lung function.

Validation of a Nutrition Screening Tool for Pediatric Patients with Cystic Fibrosis

BACKGROUND

In cystic fibrosis (CF), nutrition diagnosis is of critical relevance because the early identification of nutrition-related compromise enables early, adequate intervention and, consequently, influences patient prognosis. Up to now, there has not been a validated nutrition screening tool that takes into consideration clinical variables.

OBJECTIVE

To validate a specific nutritional risk screening tool for patients with CF based on clinical variables, anthropometric parameters, and dietary intake.

DESIGN

Cross-sectional study. The nutrition screening tool was compared with a risk screening tool proposed by McDonald and the Cystic Fibrosis Foundation criteria.

PARTICIPANTS/SETTING

Patients aged 6 to 18 years, with a diagnosis of CF confirmed by two determinations of elevated chloride level in sweat (sweat test) and/or by identification of two CF-associated genetic mutations who were receiving follow-up care through the outpatient clinic of a Cystic Fibrosis Treatment Center.

MAIN OUTCOME MEASURES

Earlier identification of nutritional risk in CF patients aged 6 to 18 years when a new screening tool was applied.

STATISTICAL ANALYSES PERFORMED

Agreement among the tested methods was assessed by means of the kappa coefficient for categorical variables. Sensitivity, specificity, and accuracy values were calculated. The significance level was set at 5% (P<0.05). Statistical analyses were carried out in PASW Statistics for Windows version 18.0 (2009, SPSS Inc).

RESULTS

Eighty-two patients (49% men, aged 6 to 18 years) were enrolled in the study. The agreement between the proposed screening tool and the tool for screening nutritional risk for CF by the McDonald method was good (κ=0.804; P<0.001) and the sensitivity and specificity was 85% and 95%, respectively. Agreement with the Cystic Fibrosis Foundation criteria was lower (κ=0.418; P<0.001), and the sensitivity and specificity were both 72%.

CONCLUSIONS

The proposed screening tool with defined clinical variables promotes earlier identification of nutritional risk in pediatric patients with CF.

Thirty Years of Sweat Chloride Testing at One Referral Center

OBJECTIVE

To conduct a descriptive analysis of the sweat test (ST), associating ST results with epidemiological data, CFTR (cystic fibrosis transmembrane conductance regulator) mutations and reasons to indicate the ST, as well as correlating sweat sodium and sweat chloride concentrations in subjects.

METHODS

Retrospective survey and descriptive analysis of 5,721 ST at a university referral center.

RESULTS

The inclusion of the subjects was based on clinical data related with cystic fibrosis (CF) phenotype. The samples were grouped by (i) sweat chloride concentrations (mEq/L): <30: 3,249/5,277 (61.6%); ≥30 to <60: 1,326/5,277 (25.1%); ≥60: 702/5,277 (13.3%) and (ii) age: (Group A--GA) 0 to <6 months; (Group B--GB) ≥6 months to <18 years; (Group C--GC) ≥18 years. Digestive symptoms showed higher prevalence ratio for the CF diagnosis as well as association between younger age and higher values of sweat chloride, sweat sodium, and chloride/sodium ratio. The indication of ST due to respiratory symptoms was higher in GB and associated with greater age, lower values of sweat chloride, sweat sodium, and chloride/sodium ratio. There was higher prevalence of ST with sweat chloride levels <30 mEq/L in GB, ≥60 mEq/L in GC, and with borderline level in GB. There was positive correlation between sweat sodium and sweat chloride. Sweat chloride/sweat sodium and sweat sodium-sweat chloride indexes showed association with sex, reason for ST indication, and CFTR mutations. Sex alters some values presented in the ST. The number of ST/year performed before and after the newborn screening implementation was the same; however, we observed a higher number of borderlines values. A wide spectrum of CFTR mutation was found. Severe CFTR mutations and F508del/F508del genotype were associated with highest probability of ST chloride levels ≥60 mEq/L, and the absence of CFTR mutations identified was associated with borderline ST and respiratory symptoms.

CONCLUSIONS

ST data showed wide variability dependent on age, sex, reason for examination indication, CFTR mutations, and weight of the collected sweat sample. Sweat sodium concentration is directly correlated with sweat chloride levels and it could be used as a quality parameter.

Synthesis and Characterization of Nanocomposite Microparticles (nCmP) for the Treatment of Cystic Fibrosis-Related Infections

PURPOSE

Pulmonary antibiotic delivery is recommended as maintenance therapy for cystic fibrosis (CF) patients who experience chronic infections. However, abnormally thick and sticky mucus present in the respiratory tract of CF patients impairs mucus penetration and limits the efficacy of inhaled antibiotics. To overcome the obstacles of pulmonary antibiotic delivery, we have developed nanocomposite microparticles (nCmP) for the inhalation application of antibiotics in the form of dry powder aerosols.

METHODS

Azithromycin-loaded and rapamycin-loaded polymeric nanoparticles (NP) were prepared via nanoprecipitation and nCmP were prepared by spray drying and the physicochemical characteristics were evaluated.

RESULTS

The nanoparticles were 200 nm in diameter both before loading into and after redispersion from nCmP. The NP exhibited smooth, spherical morphology and the nCmP were corrugated spheres about 1 μm in diameter. Both drugs were successfully encapsulated into the NP and were released in a sustained manner. The NP were successfully loaded into nCmP with favorable encapsulation efficacy. All materials were stable at manufacturing and storage conditions and nCmP were in an amorphous state after spray drying. nCmP demonstrated desirable aerosol dispersion characteristics, allowing them to deposit into the deep lung regions for effective drug delivery.

CONCLUSIONS

The described nCmP have the potential to overcome mucus-limited pulmonary delivery of antibiotics.

Association of growth and nutritional parameters with pulmonary function in cystic fibrosis: a literature review

Objective:

To review the literature addressing the relationship of growth and nutritional parameters with pulmonary function in pediatric patients with cystic fibrosis.

Data source:

A collection of articles published in the last 15 years in English, Portuguese and Spanish was made by research in electronic databases - PubMed, Cochrane, Medline, Lilacs and Scielo - using the keywords cystic fibrosis, growth, nutrition, pulmonary function in varied combinations. Articles that addressed the long term association of growth and nutritional parameters, with an emphasis on growth, with pulmonary disease in cystic fibrosis, were included, and we excluded those that addressing only the relationship between nutritional parameters and cystic fibrosis and those in which the aim was to describe the disease.

Data synthesis:

Seven studies were included, with a total of 12,455 patients. Six studies reported relationship between growth parameters and lung function, including one study addressing the association of growth parameters, solely, with lung function, and all the seven studies reported relationship between nutritional parameters and lung function.

Conclusions:

The review suggests that the severity of the lung disease, determined by spirometry, is associated with body growth and nutritional status in cystic fibrosis. Thus, the intervention in these parameters can lead to the better prognosis and life expectancy for cystic fibrosis patients.

Association of growth and nutritional parameters with pulmonary function in cystic fibrosis: a literature review

OBJECTIVE

To review the literature addressing the relationship of growth and nutritional parameters with pulmonary function in pediatric patients with cystic fibrosis.

DATA SOURCE

A collection of articles published in the last 15 years in English, Portuguese and Spanish was made by research in electronic databases - PubMed, Cochrane, Medline, Lilacs and Scielo - using the keywords cystic fibrosis, growth, nutrition, pulmonary function in varied combinations. Articles that addressed the long term association of growth and nutritional parameters, with an emphasis on growth, with pulmonary disease in cystic fibrosis, were included, and we excluded those that addressing only the relationship between nutritional parameters and cystic fibrosis and those in which the aim was to describe the disease.

DATA SYNTHESIS

Seven studies were included, with a total of 12,455 patients. Six studies reported relationship between growth parameters and lung function, including one study addressing the association of growth parameters, solely, with lung function, and all the seven studies reported relationship between nutritional parameters and lung function.

CONCLUSIONS

The review suggests that the severity of the lung disease, determined by spirometry, is associated with body growth and nutritional status in cystic fibrosis. Thus, the intervention in these parameters can lead to the better prognosis and life expectancy for cystic fibrosis patients.

Improving nutritional status in a pediatric cystic fibrosis center

BACKGROUND

The nutritional status of patients with cystic fibrosis (CF) is strongly associated with pulmonary function, respiratory status and survival. Malnutrition could result from a discrepancy between energy needs and food intake while malabsorption results from pancreatic insufficiency which occurs in 85% of people with CF.

METHODS

A quality improvement (QI) project was designed to improve the nutritional status of patients with CF with low Body Mass Index (BMI) between 3 and 19 years of age. An algorithm was developed which included clinic-based assessments of patients' nutritional status and periodic assessment by a dietitian, social worker and/or psychologist during the project. Gastrostomy tube placement and feeding was offered as a last resort to improve caloric intake.

RESULTS

173 patients seen during January-June, 2010, were included in this project. They were classified into four BMI groups and data were collected quarterly through June, 2012. The project target population (BMI percentile ≤ 24) had a median BMI percentile at the start of the project of 11.8. At the end of the project median BMI percentile was 22 (46% improvement).

CONCLUSION

Improving nutrition and BMI for patients with CF is achievable. There must be a motivated, multi-disciplinary team that includes patients and families. A patient-specific combination of interventions must be used. These interventions could be quite basic for patients with BMI percentile ≥ 25, yet more elaborate for patients with BMI percentile <25. Clinic-based algorithms such as ours can successfully improve the BMI percentile in patients with CF.

Protein is an important but undervalued macronutrient in the nutritional care of patients with cystic fibrosis

PURPOSE OF REVIEW

Achieving an optimal nutritional status in patients with cystic fibrosis (CF) is important to maintain better pulmonary function, physical performance, and to prolong survival. So far, nutrition care in CF has mainly focused on fat intake and achieving energy balance, but there is increasing information on the clinical importance of muscle maintenance and protein intake in CF.

RECENT FINDINGS

Low muscle mass is consistently associated with pulmonary decline, bone mineral loss, and poor survival in CF. High energy and fat intake contributes to an increased prevalence of overweight and obesity in CF. Obesity per se is not related to better lung function in CF and has negative metabolic and clinical consequences, particularly when muscle wasting is present. Protein digestion capacity is severely impaired in CF, but high protein intake is needed and essential amino acid mixtures appear highly anabolic even in those with severe muscle loss.

SUMMARY

Body composition assessment and achieving protein balance in the routine care in CF is important to prevent muscle loss and further improve the clinical and overall outcome of these patients. New approaches are needed to optimize the interaction between high essential amino-acid-rich protein intake and pancreatic enzyme regimen in CF. The optimal level of protein intake needs to be assessed in clinically stable CF patients as well as in those recovering from an acute exacerbation.

New stable isotope method to measure protein digestibility and response to pancreatic enzyme intake in cystic fibrosis

BACKGROUND & AIMS

Adequate protein intake and digestion are necessary to prevent muscle wasting in cystic fibrosis (CF). Accurate and easy-to-use methodology to quantify protein maldigestion is lacking in CF.

OBJECTIVE

To measure protein digestibility and the response to pancreatic enzyme intake in CF by using a new stable isotope methodology.

DESIGN

In 19 CF and 8 healthy subjects, protein digestibility was quantified during continuous (sip) feeding for 6 h by adding (15)N-labeled spirulina protein and L-[ring-(2)H5]phenylalanine (PHE) to the nutrition and measuring plasma ratio [(15)N]PHE to [(2)H5]PHE. Pancreatic enzymes were ingested after 2 h in CF and the response in protein digestibility was assessed. To exclude difference in mucosal function, postabsorptive whole-body citrulline (CIT) production rate was measured by L-[5-(13)C-5,5-(2)H2]-CIT pulse and blood samples were taken to analyze tracer-tracee ratios.

RESULTS

Protein digestibility was severely reduced in the CF group (47% of healthy subjects; P < 0.001). Intake of pancreatic enzymes induced a slow increase in protein digestibility in CF until 90% of values obtained by healthy subjects. Maximal digestibility was reached at 100 min and maintained for 80 min. Stratification into CF children (n = 10) and adults showed comparable values for protein digestibility and similar kinetic responses to pancreatic enzyme intake. Whole-body citrulline production was elevated in CF indicating preserved mucosal function.

CONCLUSION

Protein digestibility is severely compromised in patients with CF as measured by this novel and easy-to-use stable isotope approach. Pancreatic enzymes are able to normalize protein digestibility in CF, albeit with a severe delay. Registration ClinicalTrials.gov = NCT01494909.

Variation in plasma leptin levels in young Iranian children with cystic fibrosis

INTRODUCTION

Poor weight gain is one of the most important mortality hazards in cystic fibrosis (CF) patients. The mechanisms that may hinder body weight regulation are not completely understood. Leptin and its role in fat mass could be related to control of weight gain in CF patients. As the previous data are conflicting, we aimed to investigate serum leptin level in Iranian CF children compared to a control group.

MATERIAL AND METHODS

Forty-three CF patients aged from 3 to 120 months and 43 age-matched controls were enrolled. Patients were recruited from the outpatient clinic of the Children's Medical Center Hospital. Controls were visited in the general outpatient clinic for an annual check-up. Both groups were divided into three subgroups based on age: 3 to 12 months, 13 to 48 months, and 49 to 120 months. Body mass index (BMI) was calculated for all the participants. Serum leptin levels were measured applying a solid phase enzyme-linked immunosorbent assay (ELISA).

RESULTS

Leptin levels and BMI values were significantly different between patients and controls (p = 0.02, p < 0.001, respectively) but only patients aged 13-48 months had significantly higher levels of leptin than age-matched controls (p = 0.016). Overall male patients' mean leptin level was significantly higher than in female patients (p = 0.032) and male controls (p < 0.001).

CONCLUSIONS

Leptin level in our patients was significantly higher than controls. It seems that leptin levels during infancy are higher than in adult patients. Further studies are required on specific genotypes, gender and age to reveal the probable correlation with BMI and leptin levels in CF patients from different ethnic groups.

Association of nesfatin-1 and fat mass in cystic fibrosis

BACKGROUND

The mechanisms of fat mass (FM) loss in cystic fibrosis (CF) are poorly understood but could represent complex pathways involving dysregulation of appetite-modulating peptides and an amplified inflammatory response. Nesfatin-1 is a newly described peptide that decreases food intake and FM but has not been studied in CF.

OBJECTIVES

We hypothesized that changes in the appetite-suppressing hormone nesfatin-1 would be physiological, and levels would be lower in advanced CF patients with lower FM compared to those with milder disease and healthy controls. We determined the levels of the cytokines TNF-α, IL-1β, and IL-6 as they have been associated with weight loss in disease states.

METHODS

Fifty-four adult CF subjects, i.e. 17 with severe, 22 with moderate, and 15 with mild disease, as well as 18 controls were recruited. PFT and body composition analysis (via bioelectrical impedance) were performed. Nesfatin-1 and cytokine levels were determined by ELISA.

RESULTS

Contrary to our proposed hypothesis, nesfatin-1 levels were highest in CF patients with severe disease and the lowest FM. A significant negative correlation between nesfatin-1 levels and FM was found only in the severe CF group (r = -0.7, p = 0.003). In forward stepwise regression analysis, only FM was significantly associated with nesfatin-1 levels. Levels of TNF-α and IL-6 were elevated in the severe CF group, but there was no association with either FM or nesfatin-1.

CONCLUSION

In advanced CF and low FM, nesfatin-1 plasma levels are significantly increased and inversely correlated with the FM. Our results further suggest that nesfatin-1 exerts its effects independently of TNF-α or IL-6.

Measures of body habitus are associated with lung function in adults with cystic fibrosis: a population-based study

BACKGROUND

Body habitus differences may explain some of the variation in lung function between individuals with cystic fibrosis (CF). We tested the hypothesis that measures of lean muscle mass and obesity are independently associated with lung function in CF.

METHODS

Cross-sectional study design using UK CF registry data from 2096 clinically stable adults.

RESULTS

Serum creatinine and BMI were positively and independently associated with FEV1 and FVC. One standard deviation increment in serum creatinine was associated with an FEV1 increase of 171ml (95% confidence intervals CI: +116 to +227ml) in males and 90ml (95% CI: +46 to +133ml) in females. Compared to the reference group of 20-24.9kg/m(2), those with a BMI<20kg/m(2) had lower FEV1 with values of -642ml (95%CI: -784 to -500ml) for males and -468ml (95%CI: -564 to -372ml) for females.

CONCLUSIONS

Prospective studies and controlled trials are required to ascertain if these associations have therapeutic potential in modifying disease progression.

Quantitative Ultrasound in Spanish Children and Young Adults With Cystic Fibrosis

We studied the relationship between bone density and cystic fibrosis in Spanish children and young adults. We measured the phalangeal bone amplitude-dependent speed of sound (Ad-SoS) in 35 patients with cystic fibrosis and in 30 healthy controls matched for gender, age, and body mass index (BMI). Participants were subjects with normal levels of 25(OH) Vitamin D. We found no difference in Ad-SoS between patients and controls. The only difference between the groups was that the patients had a significantly higher daily caloric intake than the controls ( p < .05) as a result of the patient group's greater intake of fats ( p < .05). There was a positive correlation between Ad-SoS and weight ( p < .0001), but after adjusting for potential confounding factors such as age, the correlation was lost. The percentage of ideal weight did not differ between the two groups. We conclude that well-nourished CF patients had similar Ad-SoS to controls.

Health-related quality of life in cystic fibrosis

PURPOSE OF REVIEW

To review the contribution of various therapeutic interventions on both longevity and quality of life in cystic fibrosis patients.

RECENT FINDINGS

Long-term survival in cystic fibrosis has increased markedly in the past 25 years, largely due to a robust clinical trials program carried out at Cystic Fibrosis Foundation accredited clinical centers in the United States and similar organizations worldwide. Cystic fibrosis patients are recommended complex, time-intensive daily therapies that are often difficult for families and patients to sustain long-term. Recently, attention to the perceived value of a particular therapy on a patient's well being is recognized as important for individualizing therapeutic regimens that provide maximal clinical benefit and are more likely to be adhered to long-term by the patient. Cystic fibrosis care is in a new era in which patient-related outcomes (PROs) for the assessment of health-related quality of life (HRQOL) are regarded with equal importance to medically beneficial therapies.

SUMMARY

Numerous advances in the clinical care of cystic fibrosis have led to improved survival, although definitive correction of the abnormal cystic fibrosis transmembrane regulator protein function remains elusive. Patients struggle to maintain rigorous, time-intensive therapeutic regimens, whereas clinicians strive to identify which interventions preserve quality of life. Cystic fibrosis patients depend on their caregiver's ability to assess both the medical benefit and the contribution to quality of life that therapeutic regimes bring to their disease. Caregivers, in turn, need measures of HRQOL in order to prioritize the various therapeutic interventions that are at their disposal in order to provide not just longevity, but meaningful quality of life.

Efficacy and Safety of a New Formulation of Pancrelipase (Ultrase MT20) in the Treatment of Malabsorption in Exocrine Pancreatic Insufficiency in Cystic Fibrosis

Background. Pancreatic enzyme replacement therapy is the standard of care for treatment of malabsorption in patients with cystic fibrosis (CF) and exocrine pancreatic insufficiency (PI). Aim. To evaluate efficacy and safety of a new formulation of pancrelipase (Ultrase MT20) in patients with CF and PI. Coefficients of fat absorption (CFA%) and nitrogen absorption (CNA%) were the main efficacy parameters. Safety was evaluated by monitoring laboratory analyses, adverse events (AEs), and overall signs and symptoms. Methods. Patients (n = 31) were randomized in a crossover design comparing this pancrelipase with placebo during 2 inpatient evaluation periods (6-7 days each). Fat and protein/nitrogen ingestion and excretion were measured from food diaries and 72-hour stool collections. CFA% and CNA% were calculated for each period and compared. Results. Twenty-four patients provided analyzable data. This pancrelipase increased mean CFA% and CNA% (+34.7% and +25.7%, resp., P < .0001 for both), reduced stool frequency, and improved stool consistency compared with placebo. Placebo-treated patients reported more AEs, with gastrointestinal symptoms being the most frequently reported AE. Conclusions. This pancrelipase is a safe and effective treatment for malabsorption associated with exocrine PI in patients with CF.

Evaluation and management of pulmonary disease in ataxia-telangiectasia

Ataxia-telangiectasia (A-T) is a rare autosomal recessive disorder caused by mutations in the ATM gene, resulting in faulty repair of breakages in double-stranded DNA. The clinical phenotype is complex and is characterized by neurologic abnormalities, immunodeficiencies, susceptibility to malignancies, recurrent sinopulmonary infections, and cutaneous abnormalities. Lung disease is common in patients with A-T and often progresses with age and neurological decline. Diseases of the respiratory system cause significant morbidity and are a frequent cause of death in the A-T population. Lung disease in this population is thought to exhibit features of one or more of the following phenotypes: recurrent sinopulmonary infections with bronchiectasis, interstitial lung disease, and lung disease associated with neurological abnormalities. Here, we review available evidence and present expert opinion on the diagnosis, evaluation, and management of lung disease in A-T, as discussed in a recent multidisciplinary workshop. Although more data are emerging on this unique population, many recommendations are made based on similarities to other more well-studied diseases. Gaps in current knowledge and areas for future research in the field of pulmonary disease in A-T are also outlined.

Longitudinal growth and lung function in pediatric non-cystic fibrosis bronchiectasis: what influences lung function stability?

BACKGROUND

Longitudinal FEV(1) data in children with non-cystic fibrosis (non-CF) bronchiectasis (BE) are contradictory, and there are no multifactor data on the evolution of lung function and growth in this group. We longitudinally reviewed lung function and growth in children with non-CF BE and explored biologically plausible factors associated with changes in these parameters over time.

METHODS

Fifty-two children with > or = 3 years of lung function data were retrospectively reviewed. Changes in annual anthropometry and spirometry at year 3 and year 5 from baseline were analyzed. The impact of sex, age, cause, baseline FEV(1), exacerbation frequency, radiologic extent, socioeconomic status, environmental tobacco smoke exposure, and period of diagnosis was evaluated.

RESULTS

Over 3 years, the group mean forced expiratory flow midexpiratory phase percent predicted and BMI z-score improved by 3.01 (P = .04; 95% CI, 0.14-5.86) and 0.089 (P = .01; 95% CI, 0.02-0.15) per annum, respectively. FEV(1)% predicted, FVC% predicted, and height z-score all showed nonsignificant improvement. Over 5 years, there was improvement in FVC% predicted (slope 1.74; P = .001) annually, but only minor improvement in other parameters. Children with immunodeficiency and those with low baseline FEV(1) had significantly lower BMI at diagnosis. Frequency of hospitalized exacerbation and low baseline FEV(1) were the only significant predictors of change in FEV(1) over 3 years. Decline in FEV(1)% predicted was large (but nonsignificant) for each additional year in age of diagnosis.

CONCLUSIONS

Spirometric and anthropometric parameters in children with non-CF BE remain stable over a 3- to 5-year follow-up period once appropriate therapy is instituted. Severe exacerbations result in accelerated lung function decline. Increased medical cognizance of children with chronic moist cough is needed for early diagnosis, better management, and improving overall outcome in BE.

Nutritional considerations in patients with cystic fibrosis

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

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

A token economy for exercise adherence in pediatric cystic fibrosis: a single-subject analysis

OBJECTIVE

In cystic fibrosis (CF), adherence to airway clearance techniques (e.g., chest physiotherapy and exercise) is poor. Exercise is important because pulmonary difficulties are associated with the highest mortality rate. Despite this, very little research has focused on exercise adherence in CF. This study examined a token economy for increasing exercise in children with CF.

METHODS

An ABAB single-subject design evaluated a token economy for increasing and maintaining exercise in three children with CF. Patient report, parent report, and physiological measures were used to assess treatment integrity, medical stability, and changes in exercise.

RESULTS

Measures suggested that treatment integrity was strong. Results indicated strong treatment effects for all participants without negative medical side effects. Follow-up of 1 and 3 months supported continued exercise for all participants.

CONCLUSIONS

A token economy effectively increased exercise in children with CF, and the single-subject design highlighted some of the intricacies of individualized treatment of adherence. Implications and recommendations for further research are discussed.