Prevalence of malnutrition and obesity among cystic fibrosis patients

Evolution of nutritional management in children with cystic fibrosis - a narrative review

Nutrition has played a central role in the management and outcomes of people with cystic fibrosis (pwCF) since the 1970s. Advances in therapies and practices in recent decades have led to a significant change in the patient landscape with dramatic improvements in life expectancy, as well as quality of life, bringing with it new issues. Historically, cystic fibrosis was a condition associated with childhood and malnutrition; however, changes in patient demographics, nutritional assessment and fundamental nutritional management have evolved, and it has become an increasingly prevalent adult disease with new nutritional challenges, including obesity. This paper aims to describe these changes and the impact and challenges they bring for those working in this field. Nutritional professionals will need to evolve, adapt and remain agile to the wider range of situations and support required for a new generation of pwCF. Specialised nutrition support will continue to be required, and it will be additionally important to improve and optimise quality of life and long-term health.

The Impact of Malnutrition on the Developing Lung and Long-Term Lung Health: A Narrative Review of Global Literature

Worldwide, over 2 billion children under the age of 5 experience stunting, wasting, or are underweight. Malnutrition contributes to 45% of all deaths in this age group (approximately 3.1 million deaths) [1]. Poverty, food insecurity, suboptimal feeding practices, climate change, and conflict are all contributing factors. Malnutrition causes significant respiratory problems, including increased risk of respiratory infections, impaired lung function, and increased risk of subsequent adult respiratory disease, including asthma, COPD, and lung cancer. Childhood malnutrition not only has serious consequences for children's health but it also has numerous consequences on wellbeing and educational attainment. Childhood malnutrition is a complex and multifaceted problem. However, by understanding and addressing the underlying causes, and investing in prevention and treatment programs, it is possible to maximize children's health and wellbeing on a global scale. This narrative review will focus on the impact of childhood malnutrition on lung development, the consequent respiratory disease, and what actions can be taken to reduce the burden of malnutrition on lung health.

Association of in-line digestive enzyme cartridge with enteral feeds on improvement in anthropometrics among pediatric patients with cystic fibrosis

BACKGROUND

Approximately 85% of patients with cystic fibrosis (CF) have exocrine pancreatic insufficiency (EPI) with 10% requiring supplemental nighttime enteral tube feedings. Administration of pancreatic enzyme replacement therapy (PERT) with nighttime feedings is fraught with challenges. RELiZORB (Alcresta Therapeutics, Inc), an in-line lipase cartridge, delivers PERT continuously with enteral feedings. Outcomes related to the use of this in-line lipase cartridge are lesser known. This project evaluated anthropometrics related to in-line lipase cartridge use among pediatric patients with CF already receiving oral PERT therapy prior to nighttime enteral feedings.

METHODS

Retrospective chart review was performed on 29 patients with CF and EPI receiving supplemental tube feedings and utilizing in-line lipase cartridge for a continuous 12 month period between 2015 and 2019. Anthropometrics were evaluated 12 months before and after initiation of in-line lipase cartridge.

RESULTS

Compared with mean height z score at 6-months pre-in-line lipase cartridge, mean height z score at 6-months post-in-line-lipase cartridge (adjusted mean difference [AMD] = 0.2540; 95% CI = [0.0487, 0.4592]; P = 0.0153) and mean height z score at 12-months post-in-line lipase cartridge (AMD = 0.2684; 95% CI = [0.0203, 0.5166]; P = 0.0340) were significantly higher. Mean weight z score at 12-months post-in-line-lipase-cartridge neared statistical significance compared with 6-months pre-in-line lipase cartridge (AMD = 0.2816; 95% CI = [-0.0003, 0.5634]; P = 0.0502) when excluding seven patients with advanced lung disease (forced expiratory volume in the first second of expiration of 40%). Weight-for-length or body mass index did not significantly differ compared with pre-in-line lipase cartridge.

CONCLUSION

Use of in-line lipase cartridge with enteral feeds improved anthropometrics, especially height, in pediatric patients with CF.

ESPEN-ESPGHAN-ECFS guideline on nutrition care for cystic fibrosis

BACKGROUND

Nutritional status is paramount in Cystic Fibrosis (CF) and is directly correlated with morbidity and mortality. The first ESPEN-ESPGHAN-ECFS guidelines on nutrition care for infants, children, and adults with CF were published in 2016. An update to these guidelines is presented.

METHODS

The study was developed by an international multidisciplinary working group in accordance with officially accepted standards. Literature since 2016 was reviewed, PICO questions were discussed and the GRADE system was utilized. Statements were discussed and submitted for on-line voting by the Working Group and by all ESPEN members.

RESULTS

The Working Group updated the nutritional guidelines including assessment and management at all ages. Supplementation of vitamins and pancreatic enzymes remains largely the same. There are expanded chapters on pregnancy, CF-related liver disease, and CF-related diabetes, bone disease, nutritional and mineral supplements, and probiotics. There are new chapters on nutrition with highly effective modulator therapies and nutrition after organ transplantation.

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.

Low body mass index as a barrier to lung transplant in cystic fibrosis

RATIONALE

Low body mass index (BMI) may influence lung transplant decisions for patients with advanced cystic fibrosis (CF) lung disease.

OBJECTIVE

Determine whether patients with advanced CF lung disease and BMI ≤17 kg/m2 are less likely to be listed for lung transplant or have a higher risk of death without listing compared to those with higher BMI.

METHODS

Using merged United Network for Organ Sharing and CF Foundation Patient Registries, we identified adults with onset of advanced lung disease (FEV1 ≤ 40% predicted) between May-2005 and December-2016. We analyzed survival using competing risks regression with cause-specific risks of listing for lung transplant and death without listing. BMI ≤ 17 kg/m2 was our predictor.

MEASUREMENTS AND MAIN RESULTS

Among 5,121 CF patients with advanced lung disease, 23% were listed for lung transplant (n = 1,201), 23% died without listing (n = 1,190), and 44% were alive without listing (n = 2,730) as of December-2016. Patients with BMI ≤ 17 kg/m2 were less likely to be listed for transplant (HR 0.69; 95% CI 0.57, 0.83) and more likely to die without listing (HR 1.63; 95% CI 1.41, 1.88). We identified important regional variations in the likelihood of referral and listing, based on BMI.

CONCLUSIONS

Patients with advanced CF lung disease and BMI ≤ 17 kg/m2 are less likely to be listed for lung transplant and have a higher risk of dying without listing, compared to those with higher BMI. Regional differences suggest access to transplant for malnourished CF patients may be limited by location.

The Changing Landscape of Nutrition in Cystic Fibrosis: The Emergence of Overweight and Obesity

Cystic fibrosis has historically been characterized by malnutrition, and nutrition strategies have placed emphasis on weight gain due to its association with better pulmonary outcomes. As treatment for this disease has significantly improved, longevity has increased and overweight and obesity have emerged issues in this population. The effect of excess weight and adiposity on CF clinical outcomes is unknown but may produce similar health consequences and obesity-related diseases as those observed in the general population. This review examines the prevalence of overweight and obesity in CF, the medical and psychological impact, as well as the existing evidence for treatment in the general population and how this may be applied to people with CF. Clinicians should partner with individuals with CF and their families to provide a personalized, interdisciplinary approach that includes dietary modification, physical activity, and behavioral intervention. Additional research is needed to identify the optimal strategies for preventing and addressing overweight and obesity in CF.

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.

What Do We Know about the Microbiome in Cystic Fibrosis? Is There a Role for Probiotics and Prebiotics?

Cystic fibrosis (CF) is a life-shortening genetic disorder that affects the cystic fibrosis transmembrane conductance regulator (CFTR) protein. In the gastrointestinal (GI) tract, CFTR dysfunction results in low intestinal pH, thick and inspissated mucus, a lack of endogenous pancreatic enzymes, and reduced motility. These mechanisms, combined with antibiotic therapies, drive GI inflammation and significant alteration of the GI microbiota (dysbiosis). Dysbiosis and inflammation are key factors in systemic inflammation and GI complications including malignancy. The following review examines the potential for probiotic and prebiotic therapies to provide clinical benefits through modulation of the microbiome. Evidence from randomised control trials suggest probiotics are likely to improve GI inflammation and reduce the incidence of CF pulmonary exacerbations. However, the highly variable, low-quality data is a barrier to the implementation of probiotics into routine CF care. Epidemiological studies and clinical trials support the potential of dietary fibre and prebiotic supplements to beneficially modulate the microbiome in gastrointestinal conditions. To date, limited evidence is available on their safety and efficacy in CF. Variable responses to probiotics and prebiotics highlight the need for personalised approaches that consider an individual’s underlying microbiota, diet, and existing medications against the backdrop of the complex nutritional needs in CF.

The Relationship between Body Composition, Dietary Intake, Physical Activity, and Pulmonary Status in Adolescents and Adults with Cystic Fibrosis

Measures of body fat and lean mass may better predict important clinical outcomes in patients with cystic fibrosis (CF) than body mass index (BMI). Little is known about how diet quality and exercise may impact body composition in these patients. Dual X-ray absorptiometry (DXA) body composition, 24-h dietary recall, and physical activity were assessed in a cross-sectional analysis of 38 adolescents and adults with CF and 19 age-, race-, and gender-matched healthy volunteers. Compared with the healthy volunteers, participants with CF had a lower appendicular lean mass index (ALMI), despite no observed difference in BMI, and their diets consisted of higher glycemic index foods with a greater proportion of calories from fat and a lower proportion of calories from protein. In participants with CF, pulmonary function positively correlated with measures of lean mass, particularly ALMI, and negatively correlated with multiple measures of body fat after controlling for age, gender, and BMI. Higher physical activity levels were associated with greater ALMI and lower body fat. In conclusion, body composition measures, particularly ALMI, may better predict key clinical outcomes in individuals with CF than BMI. Future longitudinal studies analyzing the effect of dietary intake and exercise on body composition and CF-specific clinical outcomes are needed.

Obesity in cystic fibrosis

The prevalence of obesity in patients with cystic fibrosis (CF) is increasing and around one-third of adults with CF are now overweight or obese. The causes of excess weight gain in CF are likely multifactorial, including: adherence to the high-fat legacy diet, reduced exercise tolerance, therapeutic advances, and general population trends. Increased weight has generally been considered favorable in CF, correlating with improved pulmonary function and survival. While the optimal BMI for overall health in CF is unknown, most studies demonstrate minimal improvement in pulmonary function when BMI exceeds 30 kg/m2. Dyslipidemia and cardiovascular disease are important co-morbidities of obesity in the general population, but are uncommon in CF. In people with CF, obesity is associated with hypertension and higher cholesterol levels. With longer life expectancy and rising obesity rates, there may be an increase in cardiovascular disease among people with CF in coming years. Overweight CF patients are more likely to be insulin resistant, taking on features of type 2 diabetes. Treating obesity in people with CF requires carefully weighing the metabolic risks of overnutrition with the impact of low or falling BMI on lung function. This article describes current knowledge on the epidemiology, causes, consequence, and treatment of obesity in people with CF.

Influence of pancreatic status on circulating plasma sterols in patients with cystic fibrosis

Background Patients with cystic fibrosis (CF) have a reduced intestinal absorption of cholesterol and in a preliminary study we observed differences in plasma sterol profile between patients with pancreatic sufficiency (PS) and those with pancreatic insufficiency (PI). Therefore, we hypothesized that the sterol analysis may contribute to study the digestion and absorption state of lipids in patients with CF. To this aim we evaluated plasma sterols in a significant number of adult patients with CF in relation to the pancreatic status. Methods Beside cholesterol, we measured phytosterols and lathosterol as markers of intestinal absorption and hepatic biosynthesis, respectively, by gas-chromatography in plasma of adult CF patients with pancreatic sufficiency (PS-CF, n = 57), insufficiency (PI-CF, n = 97) and healthy subjects (control group, CT, n = 71). Results PI-CF patients had cholesterol and phytosterols levels significantly lower than PS-CF and CT (p < 5 × 10-10) suggesting a reduced intestinal absorption of sterols related to PI. Instead, lathosterol was significantly higher in PI-CF patients than PS-CF and CT (p < 0.0003) indicating an enhanced cholesterol biosynthesis. In PI-CF patients, phytosterols positively correlate with vitamin E (p = 0.004). Both the classes of molecules need cholesterol esterase for the intestinal digestion, thus the reduced levels of such lipids in serum from PI-CF patients may depend on a reduced enzyme activity, despite the pancreatic enzyme supplementation in all PI-CF patients. Conclusions A plasma sterols profile may be useful to evaluate the metabolic status of lipids in adult patients with CF and could help to manage the pancreatic enzyme supplementation therapy.

Academy of Nutrition and Dietetics: 2020 Cystic Fibrosis Evidence Analysis Center Evidence-Based Nutrition Practice Guideline

The Academy of Nutrition and Dietetics Evidence Analysis Center conducted a systematic review of the literature to develop an evidence-based practice guideline for primary nutrition issues in cystic fibrosis (CF). This guideline is designed to complement and build upon existing evidence-based CF nutrition guidelines. The objective of this guideline was to provide recommendations for registered dietitian nutritionists in the United States delivering medical nutrition therapy to individuals with CF and their families that fill gaps in current evidence-based guidelines on topics that are crucial in order to improve health and prevent disease progression. This guideline provides 28 nutrition recommendations to guide medical nutrition therapy, including nutrition screening, nutrition assessment, and dietary intake. For topics outside the scope of this guideline, practitioners are referred to external, evidence-based recommendations. The CF landscape is evolving rapidly with breakthroughs in cystic fibrosis transmembrane regulator modulators changing CF at a cellular level. Medical nutrition therapy for individuals with CF from infancy through advanced age requires novel and individualized approaches. The Academy Evidence Analysis Library CF guidelines provide a framework for expanding upon current knowledge to determine effective nutrition strategies for individuals with CF through long and healthy futures.

Peak glucose during an oral glucose tolerance test is associated with future diabetes risk in adults with cystic fibrosis

AIMS/HYPOTHESIS

Cystic fibrosis-related diabetes (CFRD) affects up to 50% of adults with cystic fibrosis (CF) and its presence is associated with adverse effects on nutritional status and pulmonary function. Early diagnosis could minimise CFRD morbidity, yet current methods of an OGTT at 0 and 2 h yield unreliable results. Our aim was to determine which indices from a 2 h OGTT with sampling every 30 min might improve prediction of CFRD.

METHODS

Cross-sectional analysis at baseline (n = 293) and observational prospective analysis (n = 185; mean follow-up of 7.5 ± 4.2 years) of the Montreal Cystic Fibrosis Cohort were performed. Blood glucose and insulinaemia OGTT variables were studied in relation to lung function (forced expiratory volume in 1 s [FEV1]), BMI and risk of developing CFRD.

RESULTS

At baseline, maximum OGTT glucose (G_max) was negatively associated with FEV1 (p = 0.003). Other OGTT values, including classical 2 h glucose, were not. A higher G_max was associated with lower insulin secretory capacity, delayed insulin peak timing and greater pancreatic insufficiency (p < 0.01). G_max was positively associated with the risk of developing CFRD (p = 0.0029); no individual with a G_max < 8 mmol/l developed CFRD over the following decade. No OGTT variable correlated to the rate of change in BMI or FEV1.

CONCLUSIONS/INTERPRETATION

In adults with CF, G_max is strongly associated with the risk of developing CFRD; G_max < 8 mmol/l could identify those at very low risk of future CFRD. G_max is higher in individuals with pancreatic insufficiency and is associated with poorer insulin secretory capacity and pulmonary function.

Overweight and obesity in adults with cystic fibrosis: An Italian multicenter cohort study

BACKGROUND

Over the last decades aggressive interventions have been successful to improve nutritional outcomes in people with cystic fibrosis (CF). As a result, with improvement of life expectancy and new CFTR modulators, overweight and obesity are progressively becoming a source of concern for adult population and in developed countries.

METHODS

This was a multicenter, observational, cross-sectional study of 321 adults with CF at three large CF centers in Italy. Patients were divided into three groups according to BMI classes, overweight and obesity (OW) group including patients with BMI ≥25 kg/m², normal weight (NW) group with BMI 18.6-24.9 kg/m² and underweight (UW) group with BMI ≤18.5 kg/m².

RESULTS

We demonstrated that prevalence of OW in adults with CF in Italy is 22%. OW status is independently associated with male sex (OR 3.520, P = 0.001), pancreatic sufficiency (OR 2.873, P = 0.014) and older age at diagnosis (1.015, P = 0.042). BMI correlated with ppFEV1 (r = 0.337; P<0.0001) with median ppFEV1 significantly higher in patients with OW than comparisons. We also reported preliminary data on unfavorable cardiovascular risk factors in a subgroup of patients, where median blood levels [IQR] of cholesterol and systemic hypertension [%] were significantly higher in the OW group than in the NW and UW.

CONCLUSIONS

People with CF and OW is a relevant patient group that might deserve better definition and proper clinical management.

The effects of nutritional status and intervention on pulmonary functions in pediatric cystic fibrosis patients

BACKGROUND

Cystic fibrosis (CF) causes malabsorption of nutrients that exacerbate pulmonary problems. Nutritional interventions can improve pulmonary functions. We aimed to evaluate the effects of nutritional intervention in CF patients with malnutrition, and to determine if there is a correlation between nutritional status and pulmonary functions.

METHODS

The study included 143 CF patients (67 females) with a mean 2 year follow-up time. Patients' sociodemographic data, presenting symptoms and history were recorded. Height-for-age, weight-for-age, weight-for-length/height (WFL/H), and body mass index (BMI) were calculated in all patients. Patients were grouped as well nourished, mild malnutrition, moderate malnutrition, and severe malnutrition. These four groups were compared in terms of pulmonary function test results, lung infections, and the hospitalization rate.

RESULTS

Among the patients with a WFL/H or BMI z-scores that decreased, the frequency of lung infection was 74.1% and the hospitalization rate was 40.7%, versus 34% and 12.3%, respectively among the patients with a WFL/H or BMI z-scores that increased. The difference was significant (P = 0.02 and P = 0.01, respectively). The difference in bacterial lung infections differed significantly between the four nutritional status groups (P = 0.002). Patients in the well-nourished group had significantly higher pulmonary function test scores than the other groups. The forced expiratory volume in the first second differed significantly between the patients with and without an increase in the WFL/H or BMI z-scores (P = 0.001).

CONCLUSIONS

The appropriate nutritional intervention to pediatric CF patients with malnutrition, decrease the frequency of lung infections, and improve respiratory function.

Triage for Malnutrition Risk among Pediatric and Adolescent Outpatients with Cystic Fibrosis, Using a Disease-Specific Tool

Malnutrition prevails in considerable proportions of children with Cystic Fibrosis (CF), and is often associated with adverse outcomes. For this, routine screening for malnutrition is pivotal. In the present cross-sectional study, we aimed to assess the risk for malnutrition in pediatric outpatients with CF. A total of 76 outpatients (44 girls, 11.9 ± 3.9 years old, 39.5% adolescents) were recruited and anthropometric, clinical, dietary and respiratory measures were collected. All outpatients were screened for malnutrition risk with a validated disease-specific instrument. Most children exhibited a low risk for malnutrition (78.9%), whereas none of the participants were characterized as having a high malnutrition risk. In the total sample, malnutrition risk was positively associated with age (r = 0.369, p = 0.001), and inversely related to the body mass index (r = −0.684, p < 0.001), height z-score (r = −0.264, p = 0.021), and forced expiratory volume (FEV₁%, r = −0.616, p < 0.001). Those classified as having a low malnutrition risk were younger (p = 0.004), heavier (p < 0.001) and taller (p = 0.009) than their counterparts with a moderate risk. On the other hand, patients in the moderate risk group were more likely pubertal (p = 0.034), with a reduced mid-upper arm fat area (p = 0.011), and worse pulmonary function (p < 0.001). Interestingly, none of the children attaining ideal body weight were classified as having a moderate malnutrition. risk, whereas 37.5% of the patients allocated at the moderate risk group exhibited physiological lung function. In this cohort of outpatients with CF that were predominantly well-nourished and attained physiological lung function, malnutrition risk was identified only in small proportions of the sample. Our data support that patients that are older, pubertal, or have diminished fat mass are at greater risk for malnutrition.

Cystic fibrosis patients at risk for disease progression marked by decline in FEV1% predicted: development of the cystic fibrosis risk of disease progression score

Background

Cystic fibrosis (CF) is one of the most common recessively inherited disorders diagnosed in early childhood in the United States. Determining the phenotype of CF patients likely to experience a significant drop in FEV1% predicted will help target efforts for mitigating this deleterious disorder.

Methods

This retrospective cohort study evaluated potential risk variables that account for the decline in FEV1% predicted in 81 CF patients treated at Miller Children's and Women's Hospital, CA. Cystic fibrosis risk of disease progression (CF RD-Pro) score was evaluated as a tool to identify high-risk patients for accelerated disease progression (event = drop in FEV1% predicted ≥10 percentage points) based on risk variables identified as significant.

Results

ROC analysis determined classification of high versus low-moderate risk of FEV1% decline during year two based on RD-Pro score. Scores ≥2 applied as threshold for high-risk revealed relatively good validity estimates: sensitivity =82.8%, specificity =66.7%, PVP =77.4%, PVN =73.7%, and correct classification =76%. Patients with CF RD-Pro scores suggestive of high (≥2 points) vs. low-moderate (<2 points) risk were nearly 10 times more likely to experience significant disease progression (OR 9.6, 95% CI, 2.6-36.1, P=0.001).

Conclusions

Identification of patients at high risk for significant decline in lung function will enable address of potential therapeutic modalities, environmental exposures, and behavioral variants that may improve outcomes in these patients. The power of the CF RD-Pro Score lies in its simplicity. Our study provides a novel readily available score, which incorporates body mass index (BMI) and Staphylococcus aureus infection, both being alterable targets for slowing CF progression.

Overweight, obesity and significant weight gain in adult patients with cystic fibrosis association with lung function and cardiometabolic risk factors

BACKGROUND

For patients with cystic fibrosis (CF), maintaining a normal BMI is associated with better pulmonary function (FEV1) and survival. Given therapy improvements, some patients are now overweight, obese or present rapid weight gain. However, the impact of being overweight on clinical outcomes (e.g. FEV1 & metabolic complications) remains unknown.

METHODS

Baseline data from 290 adult CF patients and observational follow-up (3.5 years; n = 158) were collected. BMI categories: underweight (UW < 18.5 kg/m²), normal (NW 18.5-26.9 kg/m²), and overweight/obese (OW ≥ 27 kg/m²). Follow-up data (weight change over time): weight loss (WL>10%), stable (WS), and weight gain (WG>10%). BMI categories and follow-up data were compared to FEV1 and cardiometabolic parameters: glucose tolerance, estimated insulin resistance (IR), blood pressure (BP), and lipid profile.

RESULTS

For BMI categories, 35 patients (12.1%) were UW, 235 (81.0%) NW, and 20 (6.9%) OW. Compared to UW and NW patients, OW patients are older (p < 0.001), had less pancreatic insufficiency (p = 0.009), a higher systolic BP (p = 0.004), higher LDL (p < 0.001), and higher IR (p < 0.001). Compared to UW patients, OW patients had a better FEV1 (p < 0.001). For weight change, WL was observed in 7 patients (4.4%), WS in 134 (84.8%) and WG in 17 patients (10.8%). Compared to WL and WS patients, WG patients had a 5% increase in FEV1 accompanied by higher IR (p = 0.017) and triglycerides (p < 0.001). No differences were observed for glucose tolerance for neither BMI nor weight change.

CONCLUSION

A higher weight or weight gain over time are associated with a better FEV₁ but also some unfavorable cardiometabolic trends.

Underweight Patients With Cystic Fibrosis Have Acceptable Survival Following Lung Transplantation: A United Network for Organ Sharing Registry Study

BACKGROUND

Reduced BMI is an absolute contraindication for lung transplantation (LTx) at most centers in the United States. The objective of this study was to quantify post-LTx survival of moderate to severely underweight patients with cystic fibrosis (CF) (BMI < 17 kg/m²) in the United States relative to normal-weight recipients with CF and other frequently transplanted patient cohorts.

METHODS

Using United Network for Organ Sharing Registry data (undergoing transplant from June 2005-November 2015), Kaplan-Meier estimates of median posttransplant survival were calculated for all patients with CF, COPD, and idiopathic pulmonary fibrosis (IPF), as well as low and normal weight CF subgroups. Cox regression modeling stratified according to transplant center assessed risk of posttransplant mortality in recipients with CF and a BMI < 17 kg/m² compared with recipients with COPD (reference).

RESULTS

Median posttransplant survival (95% CI) for CF, COPD, and IPF was 7.9 (7.2-8.6), 5.9 (5.6-6.2), and 5.5 (5.2-5.8) years, respectively. Although an absolute decrease was noted in posttransplant survival for recipients with CF and a BMI < 17 kg/m², compared with those with CF and a BMI ≥ 17 kg/m² (7.0 years [4.5-7.9] vs 8.2 years [7.3-9.0]), Cox modeling found no increased mortality risk (adjusted hazard ratio, 1.09; 95% CI, 0.90-1.32; P = .38). There was no difference in posttransplant mortality between patients with CF and a BMI < 17 kg/m² and recipients with COPD and all BMIs (adjusted hazard ratio, 1.04; 95% CI, 0.86-1.25; P = .71).

CONCLUSIONS

Transplant recipients with CF and a BMI < 17 kg/m² had posttransplant survival rates comparable to those of other groups frequently undergoing transplantation. BMI < 17 kg/m² as a single risk factor in the CF population should not be treated as an absolute contraindication to LTx.

Estimation of GFR in Patients With Cystic Fibrosis: A Cross-Sectional Study

Background

Patients with cystic fibrosis (CF) have frequent infectious complications requiring nephrotoxic medications, necessitating monitoring of renal function. Although adult studies have suggested that cystatin C (CysC)-based estimated glomerular filtration rate (eGFR) may be preferable due to reduced muscle mass of patients with CF, pediatric patients remain understudied.

Objective

Our objective was to determine which eGFR formula is best for estimating glomerular filtration rate (GFR) in pediatric patients with CF.

Methods

A total of 17 patients with CF treated with nephrotoxic antibiotics were recruited from the Children's Hospital at London Health Sciences Centre, London, Ontario, Canada. ⁹⁹Tc DTPA GFR (measured GFR [mGFR]) was measured with 4-point measurements starting at 120 minutes using a 2-compartmental model with Brøchner-Mortensen correction, with simultaneous measurement of creatinine, urea, and CysC. The eGFR was calculated using 16 known equations based on creatinine, urea, CysC, or combinations of these. Primary outcome measures were correlation with mGFR, and agreement within 10% for various eGFR equations.

Results

Mean mGFR was 136 ± 21 mL/min/1.73 m². Mean creatinine, CysC, and urea were 38 ± 10 μmol/L, 0.72 ± 0.08 mg/L, and 3.9 ± 1.4 mmol/L, respectively. The 2014 Grubb CysC eGFR had the best correlation coefficient (r = 0.75, P = .0004); however, only 35% were within 10%. The new Schwartz formula with creatinine and urea had the best agreement within 10%, but a relatively low correlation coefficient (r = 0.63, P = .0065, 64% within 10%).

Conclusions

Our study suggests that none of the eGFR formulae work well in this small cohort of pediatric patients with CF with preserved body composition, possibly due to inflammation causing false elevations of CysC. Based on the small numbers, we cannot conclude which eGFR formula is best.

Characteristics of cystic fibrosis-related diabetes: Data from two different sources the European cystic fibrosis society patient registry and German/Austrian diabetes prospective follow-up registry

BACKGROUND

Standardized patient registries provide a unique basis to get insight into cystic fibrosis (CF)-related diabetes (CFRD), the most common comorbidity in CF.

METHODS

A total of 3853 CFRD patients from the European CF Society Patient Registry (ECFSPR) and 752 from the German/Austrian diabetes prospective follow-up (diabetes patienten verlaufsdokumentation [DPV]) were studied. To adjust for age and sex, multivariable regression was used (SAS 9.4).

RESULTS

DPV subjects were younger (26.5 [20.2-32.6] vs 28.3 [21.7-36.0] years, P < 0.001) and more often female (59.6 vs 50.9%, P < 0.001). In both registries, F508del homozygotes were most frequent, with higher proportion in DPV (80.9 vs 57.8%, P = 0.003). After adjustment, lung-transplantation (LTX) was more common in ECFSPR (18.9 vs 4.9%, P < 0.001), although duration since LTX (4.8 ± 0.2 vs 5.5 ± 0.7 years, P = 0.33) did not differ. In DPV patients without LTX, a lower BMI (19.6 ± 0.1 vs 21.0 ± 0.1 kg/m² , P < 0.001), higher proportion of underweight (41.2 vs 20.2%, P < 0.001) and a tendency towards worse lung function (%FEV₁ : 42.3 ± 4.2 vs 48.3 ± 0.5%, P = 0.16) were observed.

CONCLUSIONS

Between both registries, demographic and clinical differences of CFRD were present. Besides different kind of data sources, diverse treatment structures between countries may play a role. The results may further indicate a more serious illness in patients treated in specialized diabetes clinics, documenting their data in DPV.

The Relative Contribution of Food Groups to Macronutrient Intake in Children with Cystic Fibrosis: A European Multicenter Assessment

BACKGROUND

Optimal nutrition for children with cystic fibrosis (CF) improves prognosis and survival, but an increased caloric intake recommendation for this population raises concerns about the nutrient profile of their diets.

OBJECTIVE

Our aim was to assess the relative contribution of food groups to the total macronutrient intake of European pediatric patients with CF.

DESIGN

We conducted a cross-sectional study in which the participants recorded dietary intake from 2016 to 2017. Specifically developed nutritional composition databases were used to obtain nutritional data, including macronutrients and food groups, according to previously standardized criteria.

PARTICIPANTS/SETTING

Two hundred and seven pediatric patients with CF from six European centers were involved in the My App for Cystic Fibrosis self-management project.

MAIN OUTCOME MEASURES

Participants reported dietary intake with a detailed 4-day food record.

STATISTICAL ANALYSIS PERFORMED

Descriptive analyses of nutrient intake, food group consumption, and dietary origin of macronutrients were conducted with R software.

RESULTS

Similar patterns were found in nutrient and food group intake; both sugar and saturated fatty acids contributed >10% each to the total daily energy intake in all the centers. Large mean and median percent differences were observed in the intake of other nutrient and food groups, because sweets and snacks were consumed once or twice a day, and fruit and vegetables were consumed two or three times a day. Milk, meat, sweets and snacks, and oils were the main sources of fat in all centers.

CONCLUSIONS

Study findings indicated less than optimal nutrient profiles, especially for sugars and saturated fatty acids, resulting from the high consumption of meat, dairy, and processed products and low consumption of fish, nuts, and legumes. These results can serve as a basis for future tailored interventions that target improved adherence to nutritional recommendations for patients with CF.

Evaluation of Food Insecurity in Adults and Children With Cystic Fibrosis: Community Case Study

Advances in the care and treatment of cystic fibrosis (CF) have led to improved mortality rates; therefore, considerably more individuals with CF are living into adulthood. With an increased number of CF patients advancing into adulthood, there is the need for more research that surrounds the aging adult CF patient. It is important to conduct research and collect results on the aging CF population to help better prepare the CF patient, who is dealing with the heavy treatment and financial burden of their disease, build autonomy and increase their quality of life. Of note, research has found that social, behavioral, and physical factors influence the ability of those with CF to follow dietary recommendations. A primary treatment goal in CF is a high calorie, high protein, and high fat diet. A socio-economic factor that has not been adequately investigated with regards to dietary compliance of individuals with CF is food insecurity. The aim of this community case study was to document the experiences and estimate the prevalence of food insecurity among CF patients residing in Idaho. The correlation between food insecurity and health outcomes (lung function and body mass index) was also examined. Participants included adult patients and parents of pediatric patients with CF. Food insecurity rates among CF patients of all ages were found to be significantly higher than that seen in the overall community; however, no specific correlation between food insecurity and body mass index (BMI) or lung function emerged. This case study highlights the need for continued research around food access issues in this patient population. The data resulting from this study shows the value of CF advocacy organizations promoting efforts to build resources and provide education around food insecurity issues.

EVALUATION OF NUTRITIONAL STATUS IN PATIENTS WITH CYSTIC FIBROSIS ACCORDING TO AGE GROUP

Objective:

To evaluate the nutritional profile of the population assisted at a reference center for cystic fibrosis treatment.

Methods:

Cross-sectional study including patients with cystic fibrosis assisted at a pediatric reference center in São Paulo, Brazil, in 2014. All patients attending regular visits who agreed to participate in the study were included. A questionnaire on dietary habits (24-hour diet recall) and socioeconomic characteristics was applied. Anthropometric data (compared with the reference from the World Health Organization, 2006 and 2007) and pulmonary function data were collected from medical records. Patients were stratified into age groups for statistical analysis.

Results:

A total of 101 patients were included in the study (59.4% male, 86.4% Caucasian), with median age of 10 years old. Most patients (n=77; 75%) were classified as eutrophic, but lower values of body mass index (BMI) Z scores were observed in schoolchildren and adolescents. The proportion of underweight patients was 10% (n=2) among preschoolers and 35% (n=6) of the school age group. Dietary intake was adequate, and the use of only two supplements (medium chain triglycerides and complete powdered supplement) was associated with adequacy of macronutrient intake. The socioeconomic characteristics did not show any statistical association with the nutritional state or nutritional consumption. Lung function was not significantly different between neither adolescents nor individuals with worse nutritional status in this sample.

Conclusions:

Most of the patients presented adequate nutritional status and adequate consumption of calories and macronutrients, indicating appropriate nutritional management. New studies focusing on preschool children should be performed to assess if it is possible to reduce the nutritional risk of patients with cystic fibrosis at older ages.

Cystic Fibrosis and gastroesophageal reflux disease

Gastroesophageal reflux is common in children and adults with cystic fibrosis (CF). Pathological gastroesophageal reflux disease (GERD) is also frequent in patients of all ages with CF. This article reviews the pathophysiology, diagnostic work-up, management options, complications, and future directions in the evaluation and management of GERD - unique to and pertinent for - patients with CF in particular.

Effect of synbiotic supplementation in children and adolescents with cystic fibrosis: a randomized controlled clinical trial

BACKGROUND/OBJECTIVES

Cystic fibrosis (CF) is characterized by excessive activation of immune processes. The aim of this study was to evaluate the effect of synbiotic supplementation on the inflammatory response in children/adolescents with CF.

SUBJECTS/METHODS

A randomized, placebo-controlled, double-blind, clinical-trial was conducted with control group (CG, n = 17), placebo-CF-group (PCFG, n = 19), synbiotic CF-group (SCFG, n = 22), PCFG negative (n = 8) and positive (n = 11) bacteriology, and SCFG negative (n = 12) and positive (n = 10) bacteriology. Markers of lung function (FEV₁), nutritional status [body mass index-for age (BMI/A), height-for-age (H/A), weight-for-age (W/A), upper-arm fat area (UFA), upper-arm muscle area (UMA), body fat (%BF)], and inflammation [interleukin (IL)-12, tumor necrosis factor-alpha (TNF-α), IL-10, IL-6, IL-1β, IL-8, myeloperoxidase (MPO), nitric oxide metabolites (NOx)] were evaluated before and after 90-day of supplementation with a synbiotic.

RESULTS

No significance difference was found between the baseline and end evaluations of FEV₁ and nutricional status markers. A significant interaction (time vs. group) was found for IL-12 (p = 0.010) and myeloperoxidase (p = 0.036) between PCFG and SCFG, however, the difference was not maintained after assessing the groups individually. NOx diminished significantly after supplementation in the SCFG (p = 0.030). In the SCFG with positive bacteriology, reductions were found in IL-6 (p = 0.033) and IL-8 (p = 0.009) after supplementation.

CONCLUSIONS

Synbiotic supplementation shown promise at diminishing the pro-inflammatory markers IL-6, IL-8 in the SCFG with positive bacteriology and NOx in the SCFG in children/adolescents with CF.

High attainment of optimal nutritional and growth status observed among Greek pediatric cystic fibrosis patients: results from the GreeCF study

BACKGROUND

Pediatric cystic fibrosis (CF) patients suffer high rates of undernutrition, subject to several parameters. We aimed to assess growth and nutritional status of Greek children and adolescents with CF.

METHODS

Eighty-four patients (35 boys) formed the sample. Anthropometrics and FEV1 were measured, growth and weight status were assessed. Body mass index (BMI), arm circumference (MUAC), fat (MUAFA) and muscle (MUAMA) were calculated.

RESULTS

In the total sample, 6.0% of the patients were underweight, 4.8% stunted, 8.3% wasted and 17.9% in nutritional failure, whereas 59.5% attained the ideal BMI for CF. FEV1 positively associated with BMI (B=0.03, p≤0.003), weight (B=0.03, p≤0.003) and MUAMA z-scores (B=0.04, p≤0.005). Meconium ileus negatively associated with FEV1 (B=-14.17, p≤0.003) and stature (B=-0.65, p≤0.043). Pancreatic insufficiency negatively influenced MUAC and MUAFA z-scores (p≤0.05 for both).

CONCLUSIONS

The examined CF patients appear to be thriving. Unlike published research, the participants' sex, gene mutation and acquisition of pathogens did not affect growth.

Survival after lung transplantation for cystic fibrosis in Sweden

Objectives

In Sweden, lung transplantation has been performed in patients with end-stage lung disease since 1990. We assessed survival after lung transplantation for cystic fibrosis (CF) with focus on early mortality and outcome for patients infected with certain multiresistant bacteria, considered a relative contraindication for lung transplantation.

Methods

Review of CF and transplant databases and patient charts. The Kaplan-Meier method and log-rank test were used for survival analysis and group comparison.

Results

From November 1991 to December 2014, 115 transplantations were performed in 106 CF patients (9 retransplantations): 3 heart-lung, 106 double lung-, 1 double lobar- and 5 single lung transplantations, constituting 13% (115/909) of all lung-transplant procedures performed in Sweden. The mean age at surgery was 31 (SD 10, range 10-61) years and there were 48% females. Overall 1-year survival after lung transplantation for CF was 86.4%, 5-year survival was 73.7% and 10-year survival was 62.4%. The mean and median survival after transplantation were 13.1 (95% confidence interval (CI): 11-15.3) and 14.6 (95% CI: 9.3-19.8) years, respectively, and there was no significant difference for gender or transplant centre. Extracorporeal membrane oxygenation was used as a bridge to transplantation in 11 cases and five patients received reconditioned lungs. Vascular and infectious complications contributed to eight deaths within the first three postoperative months. The mean survival for 14 patients infected pretransplant with Mycobacterium abscessus or Burkholderia cepacia complex was 8.8 (95% CI: 6.1-11.6) years compared to 13.2 (95% CI: 10.9-15.8) years for patients negative for these bacteria. Nineteen patients (14% of all listed), of whom three were listed for retransplantation, died while waiting a median time of 94 days (range 4 days-2.5 years) after listing.

Conclusions

Survival after lung transplantation in Sweden is good, also for patients with pretransplant infection with M. abscessus or B. cepacia complex, and comparable to international data.

Glucose tolerance & insulin secretion & sensitivity characteristics in Indian children with cystic fibrosis: A pilot study

Background & objectives

Cystic fibrosis (CF) is a life-limiting genetic condition resulting in chronic respiratory infections, pancreatic enzyme insufficiency and associated complications. This pilot study was undertaken to assess the glucose tolerance and insulin secretion and sensitivity among Indian children with CF.

Methods

Children with CF under regular follow up at the Paediatric Pulmonology Clinic of a tertiary care hospital in New Delhi, India, were enrolled. Children who had a history of acute exacerbation or intake of systemic steroids within the last two weeks were excluded. Anthropometry, pulmonary function and disease severity (Shwachman) score were assessed. Fasting venous sample was drawn to assess glucose, insulin, haemoglobin and calcium. Oral glucose tolerance test was performed, and blood glucose and insulin were assessed at 30, 60, 90 and 120 min. Insulin secretion and sensitivity indices were calculated.

Results

Twenty nine patients with a mean age of 11.2±4.1 yr were enrolled. Stunting, thinness, anaemia and hypocalcaemia were present in 31.0, 13.8, 37.0 and 48.3 per cent of the patients, respectively. Abnormal glucose tolerance (AGT) was present in 21.4 per cent. Insulin secretion was similar in individuals with AGT and normal glucose tolerance (NGT), but insulin sensitivity index was lower (0.12±0.02 vs 0.15±0.01, P<0.001) and homeostatic model assessment of insulin resistance higher [1.63 (0.53-1.76) vs 0.83 (0.28-4.43), P<0.05] in individuals with AGT compared to NGT.

Interpretation & conclusions

AGT was observed in 21.4 per cent of children with CF. The CF patients with AGT had significantly lower insulin sensitivity compared to patients with NGT. Future multicentric studies with a large sample should be conducted to assess insulin secretion and sensitivity indices in CF patients compared to healthy controls.

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.

Survival of Patients with Cystic Fibrosis Depending on Mutation Type and Nutritional Status

The purpose of the study was to evaluate the influence of nutrition and of the severity of mutation type on survival rate in cystic fibrosis (CF) patients. Data were longitudinally collected from 60 hospitalized adult CF patients, aged 18-50. The variables consisted of body mass index (BMI) ratio, Cole's BMI cut-off points, severity of mutation type, and survival rate of CF patients. We found that the mean BMI was strongly associated with the severity of mutation type and was significantly lower in patients with severe mutations of grade I and II. The mutation type significantly affected the patients' survival rate; survival was greater in patients with mild and undefined mutation types. The BMI and Cole's cut-off points also had a significant influence on survival rate. CF patients, who suffered from malnutrition and emaciation, had a shorter survival rate than those with proper nutritional status. In conclusion, the study findings confirmed a significant effect of nutritional status and of mutation type on survival rate of CF patients.

Exercise capacity following a percutaneous endoscopic gastrostomy in a young female with cystic fibrosis: a case report

Cystic fibrosis (CF) is a genetic condition affecting the respiratory and gastrointestinal systems, with patients experiencing problems maintaining weight, especially during rapid growth periods such as puberty. The aim of this case report was to monitor the effect of gastrostomy insertion and implementation of overnight supplemental feeding upon clinical outcomes, including body mass index (BMI), lung function (FEV₁), and exercise‐related variables (maximal oxygen uptake [VO_2max] and ventilatory efficiency [V_E/VO₂]) in an 11‐year‐old female with CF. Combined incremental and supramaximal exercise testing to exhaustion was performed at four time points: 3 months prior to the procedure (T1), 2 days prior to (T2), 4 months (T3), and 1 year following the procedure (T4). Improvements following gastrostomy insertion were observed at the 1 year follow‐up with regards to BMI (+20%); whereas absolute VO_2max remained stable and lung function fluctuated throughout the period of observation. Declines in function with regards to body weight relative VO_2max (−16.3%) and oxygen uptake efficiency (+7.5%) were observed during this period. This case report is the first to consider exercise‐related clinical outcomes in assessing the effect of implementing gastrostomy feeding in CF. The varied direction and magnitude of the associations between variables shows that further investigations are required.

Body composition and lung function in cystic fibrosis and their association with adiposity and normal-weight obesity

OBJECTIVES

This study aimed to evaluate the relationship between lung function and body composition in cystic fibrosis (CF) and examine the presence of normal-weight obesity (NWO), a high body fat percentage with a normal body mass index (BMI), in this population.

METHODS

In a pilot, cross-sectional study, 32 subjects with CF and a reference group of 20 adults without CF underwent body composition analysis with air displacement plethysmography. NWO was defined as a BMI <25 kg/m(2) and body fat >30% (for women) or >23% (for men). Lung function in subjects with CF was determined by the percentage of predicted forced expiratory volume in 1 s (FEV1% predicted).

RESULTS

Despite lower BMI and fat-free mass index (P < 0.01), fat mass index and percent body fat did not differ between subjects with CF and the reference group. Among subjects with CF, FEV1% predicted was positively associated with fat-free mass index (β = 6.31 ± 2.93, P = 0.04) and inversely associated with fat mass index (β = -6.44 ± 2.93, P = 0.04), after adjusting for age, sex, and BMI. Ten subjects with CF (31%) had NWO, which corresponded with lower fat-free mass index and FEV1% predicted compared with overweight subjects (P = 0.006 and 0.004, respectively).

CONCLUSIONS

Excess adiposity, particularly in the form of NWO, was inversely associated with lung function in CF. Larger prospective studies should be undertaken to confirm these findings and determine the long-term metabolic and clinical consequences of excess adiposity in CF. As the lifespan of individuals with CF increases, nutrition screening protocols, which primarily rely on BMI, may require reassessment.

Nutritional advances in patients with respiratory diseases

Nutritional issues are increasingly recognised in the course of respiratory diseases, from primary prevention to advanced disease care. During the 2014 ERS International Congress in Munich, Germany, the topic was addressed in a Clinical Year in Review session. This review highlights new insights in generic and disease-specific nutritional issues from recently published peer-reviewed articles. The clinical relevance of obesity was highlighted in primary and secondary prevention across all respiratory diseases. Radiographic imaging was explored for characterisation of metabolic phenotypes as an integrated part of diagnostic work-up. Muscle regenerative defects and the autophagy-lysosome pathway were identified as new leads for combatting muscle wasting.

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.

Cystic fibrosis related diabetes

Improved life expectancy in cystic fibrosis (CF) has led to an expanding population of adults with CF, now representing almost 50 % of the total CF population. This creates new challenges from long-term complications such as diabetes mellitus (DM), a condition that is present in 40 %-50 % of adults with CF. Cystic fibrosis-related diabetes (CFRD) results from a primary defect of insulin deficiency and although sharing features with type 1 (DM1) and type 2 diabetes (DM2), it is a clinically distinct condition. Progression to diabetes is associated with poorer CF clinical outcomes and increased mortality. CFRD is not associated with an increased risk of cardiovascular disease and the prevalence of microvascular complications is lower than DM1 or DM2. Rather, the primary goal of insulin therapy is the preservation of lung function and optimization of nutritional status. There is increasing evidence that appropriate screening and early intervention with insulin can reverse weight loss and improve pulmonary function. This approach may include targeting postprandial hyperglycemia not detected by standard diagnostic tests such as the oral glucose tolerance test. Further clinical research is required to guide when and how much to intervene in patients who are already dealing with the burden of one chronic illness.

Pathophysiology of cystic fibrosis and drugs used in associated digestive tract diseases

Cystic fibrosis (CF) causes chronic infections in the respiratory tract and alters the digestive tract. This paper reviews the most important aspects of drug treatment and changes in the digestive tract of patients with CF. This is a review of the literature, emphasizing the discoveries made within the last 15 years by analyzing scientific papers published in journals indexed in the Scientific Electronic Library Online, Sciences Information, United States National Library of Medicine and Medical Literature Analysis and Retrieval System Online databases, both in English and Portuguese, using the key words: cystic fibrosis, medication, therapeutic, absorption, digestion. Randomized, observational, experimental, and epidemiological clinical studies were selected, among others, with statistical significance of 5%. This review evaluates the changes found in the digestive tract of CF patients including pancreatic insufficiency, constipation and liver diseases. Changes in nutritional status are also described. Clinical treatment, nutritional supplementation and drug management were classified in this review as essential to the quality of life of CF patients, and became available through public policies for monitoring and treating CF. The information gathered on CF and a multi professional approach to the disease is essential in the treatment of these patients.