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

Close monitoring and early intervention: management principles for cystic fibrosis in Denmark

Cystic fibrosis (CF) care in Denmark has been characterized by close monitoring and pre-emptive treatment of lung disease and other CF-related complications. Continuous evaluation through data collection and commitment to clinical research has incrementally improved outcomes. This approach has been in line with best practices set forth by European Standards of Care but has also gone beyond Society standards particularly pertaining to early treatment with high-dose combination antimicrobial therapy. Despite a high prevalence of severe CF variants, lung function has been among the best in Europe. In this review, the Danish approach to management of CF prior to the introduction of new CF modulator treatment is explained and benchmarked. Downsides to the Danish approach are discussed and include increased burden of treatment, risk of antimicrobial resistance, side-effects and costs.

Trends in Growth and Maturation in Children with Cystic Fibrosis Throughout Nine Decades

Since cystic fibrosis (CF) was first described in 1938, there have been many discoveries and innovations in the field, each having a profound impact on survival, growth and quality of life. For example, the introduction of enteric-coated pancreatic enzyme microspheres increased fat absorption and improved nutritional status. Early detection of CF through newborn screening facilitated prompt nutritional intervention for infants at high risk of malnutrition. Use of anti-pseudomonal therapy, such as inhaled tobramycin, increased weight gain and pulmonary function in addition to reducing pulmonary exacerbations. Similarly, DNAse and hypertonic saline improved pulmonary function and reduced exacerbations. The identification of the CFTR gene and its protein product were fundamental in understanding the pathophysiology of CF and paved the way for advances in both diagnosis and management. In fact, CFTR modulator therapies have revolutionized the care for individuals with CF. Here, we examine the impact of these interventions on the nutritional status, growth and pubertal maturation of children and adolescents with CF.

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.

A cross-sectional study of growth, nutritional status and body proportions in children and adolescents at a medical center specializing in the treatment of cystic fibrosis in Poland

INTRODUCTION

Malnutrition, delayed growth and delayed puberty are commonly seen in children with cystic fibrosis. The aim of this study was to evaluate growth, nutritional status and body proportions in children and adolescents suffering from cystic fibrosis.

MATERIAL AND METHODS

The evaluation was based on 19 somatic measurements and indices calculated from these measurements. Somatic development was evaluated in relation to several factors connected to the clinical picture or the course of the disease. Anthropometric data were extracted from the medical histories of 41 boys and 48 girls diagnosed and treated at the Institute of Mother and Child in Warsaw (Poland). Mean values for somatic parameters and body build indices for the children suffering from CF were compared to those for the reference group.

RESULTS

The results revealed that growth in these children was significantly delayed in comparison to that seen in the healthy population (Z-score = -0.56, p < 0.001). Nutritional status was also adversely affected (Z-score = -0.85, p < 0.001). The children suffered more from a deficit in muscularity than in adiposity (Z-score = -0.75 and Z-score = -0.34, p < 0.01, respectively). This was especially true for boys. The children had infantile body proportions and defects in trunk and chest structure.

CONCLUSIONS

The factors that most affected somatic development were infection by Pseudomonas aeruginosa and the time at which the disease was diagnosed. Chronic infection by P. aeruginosa and type of CFTR mutation were the factors that most affected pulmonary function parameters.

Candidate markers associated with the probability of future pulmonary exacerbations in cystic fibrosis patients

Introduction

Pulmonary exacerbations (PEs) cause significant morbidity and can severely impact disease progression in cystic fibrosis (CF) lung disease, especially in patients who suffer from recurrent PEs. The assessments able to predict a future PE or a recurrent PE are limited. We hypothesized that combining clinical, molecular and patient reported data could identify patients who are at risk of PE.

Methods

We prospectively followed a cohort of 53 adult CF patients for 24 months. Baseline values for spirometry, clinical status using the Matouk Disease Score, quality of life (QOL), inflammatory markers (C-reactive protein (CRP), interleukins (IL)-1β, -6, -8, -10, macrophage inflammatory protein (MIP)-1β, tumor necrosis factor (TNF) and vascular endothelial growth factor (VEGF)), polyunsaturated fatty acids and lipid peroxidation in blood plasma were collected for all patients during periods of stable disease, and patients were monitored for PE requiring PO/IV antibiotic treatment. Additionally, we closely followed 13 patients during PEs collecting longitudinal data on changes in markers from baseline values. We assessed whether any markers were predictors of future PE at baseline and after antibiotic treatment.

Results

Out of 53 patients, 37 experienced PEs during our study period. At baseline, we found that low lung function, clinical scoring and QOL values were associated with increased risk of PE events. PEs were associated with increased inflammatory markers at Day 1, and these biomarkers improved with treatment. The imbalance in arachidonic acid and docosahexaenoic acid levels improved with treatment which coincided with reductions in lipid peroxidation. High levels of inflammatory markers CRP and IL-8 were associated with an early re-exacerbation.

Conclusion

Our results demonstrate that worse clinical and QOL assessments during stable disease are potential markers associated with a higher risk of future PEs, while higher levels of inflammatory markers at the end of antibiotic treatment may be associated with early re-exacerbation.

Growth and pulmonary outcomes during the first 2 y of life of breastfed and formula-fed infants diagnosed with cystic fibrosis through the Wisconsin Routine Newborn Screening Program

BACKGROUND

The optimal feeding (breast milk, formula, or a combination) for infants with cystic fibrosis (CF) is unknown. Recommendations from the CF Foundation are based on limited data.

OBJECTIVE

We compared growth and pulmonary outcomes between breastfed and formula-fed infants through the age of 2 y.

DESIGN

A total of 103 CF infants born in 1994-2006 and diagnosed through newborn screening in Wisconsin were studied. Breastfed infants were classified by the duration of exclusive breastfeeding (ExBF). Exclusive formula-feeding (ExFM) was classified by the formula's caloric density (ie, standard [0.67 kcal/mL (20 kcal/oz) (ExFM20)] throughout infancy or high density [≥0.74 kcal/mL (22 kcal/oz) (ExFM22+)] for some duration of infancy).

RESULTS

Fifty-three infants (51% of infants) were breastfed and 50 infants (49% of infants) were ExFM. In breastfed infants, the duration of ExBF was <1 mo (53% of infants), 1-1.9 mo (21% of infants), 2-3 mo (17% of infants), and 4-9 mo (9% of infants). In ExFM infants, 23 infants (46%) received a formula with a high caloric density; approximately half (n = 13) of the ExFM infants received the formula by 6 mo of age. Proportionately more infants with pancreatic sufficiency (n = 9) were ExBF ≥1 mo (44% of infants), and none of the infants were ExFM22+, compared with infants with meconium ileus (n = 24; 13% of infants were ExBF ≥1 mo, and 38% of infants were ExFM22+) or pancreatic insufficiency (n = 70; 25% of infants were ExBF ≥1 mo, and 20% of infants were ExFM22+) (P = 0.02). In infants with pancreatic insufficiency, weight z scores declined from birth to 6 mo (P < 0.0001) in infants who were ExBF ≥2 mo, and the number of Pseudomonas aeruginosa infections through the age of 2 y was fewer in breastfed than in ExFM infants (P = 0.003) but did not differ by the duration of ExBF.

CONCLUSION

For infants with CF, ExBF <2 mo does not compromise growth and is associated with a respiratory benefit.

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

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

Growth and nutritional status in children and adolescents with cystic fibrosis

BACKGROUND

Growth retardation, delayed puberty and malnutrition are frequently observed in children suffering from cystic fibrosis.

AIM

The aim of this study was to estimate growth and nutritional status in children with cystic fibrosis on the basis of body proportions and body mass index.

SUBJECTS AND METHODS

Anthropometric data were collected from the medical histories of 62 patients treated in three cystic fibrosis treatment centers in Poland. Anthropometric parameters were expressed in terms of standard deviations away from age-specific and sex-specific reference means reported for the population of Poland. Two-way analysis of variance was used to determine whether the type of cystic fibrosis transmembrane conductance regulator (CFTR) mutation is correlated with age at the time of diagnosis and with body proportions.

RESULTS

The type of mutation was significantly correlated with height, weight and transverse chest width. Growth retardation was greater in subjects diagnosed before they were 3 years old than in subjects diagnosed later. The children had infantile body proportions. Their legs were short and their trunks were long in comparison to their height. Almost 40% of the subjects suffered from malnourishment.

CONCLUSION

Further study is needed to determine how growth in children with cystic fibrosis is affected by clinical practice and socio-economic factors.

Evidence-based practice recommendations for nutrition-related management of children and adults with cystic fibrosis and pancreatic insufficiency: results of a systematic review

The Cystic Fibrosis Foundation established a process of systematic review of evidence to inform the development of clinical care guidelines and encourage evidence-based practice. The Subcommittee on Growth and Nutrition reviewed the evidence in two areas: energy intake and dosing for pancreatic enzyme replacement therapy. Evidence-based recommendations are presented here. Also, an ad hoc working group conducted a review of the literature and performed new analyses using the Cystic Fibrosis Foundation Patient Registry to update the recommendations for growth and weight-status monitoring. These Registry data-based recommendations are presented.

[Cystic fibrosis: review]

Cystic Fibrosis (CF) is the recessive autossomic disease more frequent in the caucasian race. The main characteristic is a mutation in CFTR, a trans-membranar protein, responsible for chlorates transportation. This protein has a diffuse epithelial distribution, which gives a multissistemic involvement to this disease, with clinical manifestations with variable degrees of severity. The development of better health care associated with new therapeutic options became responsible for an increase of survival, so CF is no longer a paediatric disease. Lung transplantation also has an important role, bringing new treatment perspectives. So, this pathology has an increased multi-disciplinary involvement in which the pulmonologist have a preponderant role.

Capacidade submáxima de exercício em pacientes adolescentes e adultos com fibrose cística

OBJETIVO: Determinar a capacidade submáxima de exercício através do teste de caminhada de seis minutos (TC6) em pacientes com fibrose cística (FC), correlacionando-a com: escore clínico, estado nutricional, escore radiológico e função pulmonar. MÉTODOS: O estudo realizado foi transversal e prospectivo, em pacientes (16 anos ou mais), atendidos em um programa para adultos com FC. Os pacientes foram submetidos a uma avaliação clínica, ao TC6, à medida das pressões respiratórias máximas, a espirometria e exame radiológico do tórax. RESULTADOS: O estudo incluiu 41 pacientes com média de idade de 23,7 ± 6,5 anos e média de volume expiratório forçado no primeiro segundo (VEF1) de 55,1 ± 27,8%. Em 30 pacientes (73,2%), a distância percorrida (556,7 ± 76,5 m) esteve abaixo do limite inferior previsto da normalidade. Não houve correlação significativa entre a distância percorrida e o índice de massa corporal, escore clínico, escore radiológico, pressões respiratórias máximas, saturação periférica de oxigênio em repouso, dessaturação durante o TC6, sensação de dispnéia e fadiga. Observou-se correlação significativa entre a distância percorrida e idade do diagnóstico, VEF1 em litros e capacidade vital forçada em litros. O prejuízo da função pulmonar se associou com maior dessaturação no TC6. CONCLUSÃO: Este estudo mostrou que a maioria dos pacientes atendidos por um programa de adultos para FC apresentaram redução na capacidade submáxima de exercício. O TC6 mostrou-se útil para identificar os pacientes que poderiam apresentar dessaturação de oxigênio e limitação física durante suas atividades diárias.

Nutrition and Lung Disease in Cystic Fibrosis

Among patients who have cystic fibrosis (CF), lung disease is a significant contributor to morbidity. From a clinical perspective, the link between malnutrition and lung dysfunction in CF is well established; however, the causal relationship remains unclear. Nutritional intervention for CF patients is predicated on the hypothesis that improved nutritional status improves pulmonary function. Which interventions will be of most value and have sustained gains is not completely clear from the available data. Taking into account that several factors condition the deficits that lead to malnutrition in CF, multidisciplinary interventions are likely to give the best results. More research is needed to better dissect the nutritional factors involved in lung disease and to identify effective and safe interventions through systematic controlled trials.

Antimicrobial therapy for pulmonary pathogenic colonisation and infection by Pseudomonas aeruginosa in cystic fibrosis patients

Pseudomonas aeruginosa colonisation has a negative effect on pulmonary function in cystic fibrosis patients. The organism can only be eradicated in the early stage of colonisation, while reduction of bacterial density is desirable during chronic colonisation or exacerbations. Monthly, or at least 3-monthly, microbiological culture is advisable for patients without previous evidence of P. aeruginosa colonisation. Cultures should be performed at least every 2-3 months in patients with well-established colonisation, and always during exacerbations or hospitalisations. Treatment of patients following the first isolation of P. aeruginosa, but with no clinical signs of colonisation, should be with oral ciprofloxacin (15-20 mg/kg twice-daily for 3-4 weeks) plus inhaled tobramycin or colistin (intravenous treatment with or without inhaled treatment can be used as an alternative), while patients with acute infection should be treated for 14-21 days with high doses of two intravenous antimicrobial agents, with or without an inhaled treatment during or at the end of the intravenous treatment. Maintenance treatment after development of chronic P. aeruginosa infection/colonisation (pathogenic colonisation) in stable patients (aged>6 years) should be with inhaled tobramycin (300 mg twice-daily) in 28-day cycles (on-off) or, as an alternative, colistin (1-3 million units twice-daily). Colistin is also a possible choice for patients aged<6 years. Treatment can be completed with oral ciprofloxacin (3-4 weeks every 3-4 months) for patients with mild pulmonary symptoms, or intravenously (every 3-4 months) for those with severe symptoms or isolates with ciprofloxacin resistance. Moderate and serious exacerbations can be treated with intravenous ceftazidime (50-70 mg/kg three-times-daily) or cefepime (50 mg/kg three-times-daily) plus tobramycin (5-10 mg/kg every 24 h) or amikacin (20-30 mg/kg every 24 h) for 2-3 weeks. Oral ciprofloxacin is recommended for patients with mild pulmonary disease. If multiresistant P. aeruginosa is isolated, antimicrobial agents that retain activity are recommended and epidemiological control measures should be established.

Risk factors for allergic bronchopulmonary aspergillosis and sensitisation to Aspergillus fumigatus in patients with cystic fibrosis

An increasing incidence of allergic bronchopulmonary aspergillosis (ABPA) as a complication in patients with cystic fibrosis (CF) is reported. The objective of this retrospective case-control study was to assess potential risk factors for ABPA and for Aspergillus fumigatus sensitisation (AFS). In a group of 160 CF patients, 11 (7%) fulfilled the diagnostic criteria for ABPA and 20 (13%) had evidence of AFS. They were compared to 62 control CF patients (25 for ABPA and 37 for AFS group) without evidence of ABPA or AFS using extended matching for sex, age and weight. AFS patients had received significantly higher cumulative doses of inhaled corticosteroids than their respective controls (OR 8.0; 95% CI 1.74-63). Bronchial colonisation with Stenotrophomonas maltophilia was strongly and independently associated with ABPA (OR 20; 95% CI 2.8- infinity). A longer duration of Pseudomonas aeruginosa colonisation was independently associated with AFS (OR per year 1.50; 95% CI 1.12- infinity).

CONCLUSION

Cystic fibrosis patients with allergic bronchopulmonary aspergillosis have a more frequent isolation of S. maltophilia in their sputum than their controls. Longer duration of colonisation with P. aeruginosa is a risk factor for Aspergillus fumigatus sensitisation. Higher cumulative doses of inhaled corticosteroids are associated with Aspergillus fumigatus sensitisation and their role as a risk factor needs to be clarified.

Malnutrition in adults with cystic fibrosis

OBJECTIVE

To determine the prevalence and clinical features of malnutrition and its relationship with the CFTR genotype in a cystic fibrosis (CF) adult population.

DESIGN

Cross-sectional study.

SETTING

Department of Pulmonology, Cochin Hospital, Paris, France.

SUBJECTS

163 CF adults seen between 1997 and 1999.

RESULTS

Mean age was 28.8 y. Mean body mass index (BMI) was 19.1 kg/m2. Malnutrition (BMI<18.5 kg/m2) was seen in 81 patients (49.7%). Its severity was associated with diagnosis of CF before the age of 18 y (P<0.01), FEV1 values below 30% (P<0.01), the yearly decline of FEV1 (P<0.01), pancreatic insufficiency (P<0.01) and gastro-oesophageal reflux (P<0.01). Malnutrition was observed in 58.7% of patients with a severe CFTR genotype but in 28.6% of patients with a mild genotype (P<0.001).

CONCLUSION

Malnutrition remains frequent in adults with CF except in patients presenting with a mild CFTR genotype (leading to a mild phenotype and to later diagnosis).

Multiple breath inert gas washout as a measure of ventilation distribution in children with cystic fibrosis

BACKGROUND

Multiple breath inert gas washout (MBW) has been suggested as a tool for detecting early cystic fibrosis (CF) lung disease. A study was undertaken to compare the relative sensitivity of MBW and spirometry for detecting abnormal lung function in school age children with CF and to compare MBW results obtained from healthy children in the UK with those recently reported from Sweden.

METHODS

Forced expiratory volume in 1 second (FEV1) and maximal expiratory flow when 25% of forced vital capacity remains to be expired (MEF25) were compared with the lung clearance index (LCI) derived from sulphur hexafluoride MBW in 22 children with CF aged 6-16 years and in 33 healthy controls.

RESULTS

LCI was higher in children with CF than in healthy controls (mean difference 5.1 (95% CI of difference 4.1 to 6.1) and FEV1 and MEF25 z-scores were lower (mean difference -2.3 (95% CI -2.9 to -1.7) and -1.8 (95% CI -2.4 to -1.3), respectively; p<0.001 for all). There was a significant negative correlation between LCI and FEV1 (r2 = 0.62) and MEF25 (r2 = 0.46). However, while normal (> or =-1.96 z-scores) FEV1 and MEF25 results were seen in 11 (50%) and 12 (53%) children with CF, respectively, all but one of these children had an abnormally increased LCI. LCI was repeatable in both groups (within subject CV for three measurements 6% for CF and 5% for healthy children). In healthy subjects LCI was independent of age and virtually identical in the British and Swedish children (mean difference 0.1 (95% CI -0.1 to 0.4), p = 0.38)

CONCLUSIONS

MBW is reproducible between laboratories, generates normal ranges which are constant over childhood, and is more frequently abnormal than spirometry in children with CF.

Association of nutritional status and pulmonary function in children with cystic fibrosis

PURPOSE OF REVIEW

Multiple studies have shown that nutritional status is a strong predictor of morbidity and mortality in patients with cystic fibrosis (CF). Since CF is characterized by progressive lung disease, it could be argued that the underlying lung disease is what determines the nutritional failure seen in most patients. This review will summarize the data available from studies that have attempted to better define this relation and also present a review of the possible mechanisms involved taken from both observational and interventional studies.

RECENT FINDINGS

Longitudinal studies with sufficiently large follow-up times have demonstrated that young underweight patients have worst pulmonary function outcomes. More importantly, these studies concur in that the yearly change in growth parameters has a significant effect on the rate at which pulmonary function develops. Although the mechanisms behind this important association are yet unclear, there is some suggestion from interventional studies that the accrual of lean body mass is the factor that is involved in the preservation of lung function.

SUMMARY

Nutritional status strongly influences pulmonary health among CF patients. Therefore, aggressive nutritional support aiming at achieving normal growth patterns should lead to adequate development of lung function and maintenance of pulmonary health. However, more research is required with long-term longitudinal studies to better identify the most critical nutritional characteristics influencing this process as well as the most effective nutritional interventions.

Assessment of nutritional status in children with cystic fibrosis: conventional anthropometry and bioelectrical impedance analysis. A cross-sectional study in Dutch patients

BACKGROUND

Assessment of nutritional status in children with cystic fibrosis (CF) is clinically relevant. Methods to measure nutritional status should be reliable and non-invasive, and reference values should be available.

AIM

To compare weight and height measurements and measurements of specific body compartments in children with CF.

METHODS

In a cross-sectional survey of 58 children with CF (28 females), we compared height and weight (expressed as: weight-for-height, body mass index (BMI), height-for-age and weight-for-age) with fat mass (skinfold sum (SFS)), muscle mass (upper arm circumference (UAC)) and bioelectrical impedance analysis (BIA). Results were expressed as Z-scores, using Dutch reference values.

RESULTS

BMI and weight-for-height were within the normal range (mean Z-score (range): -0.13 (-1.5, 2.7) and -0.02 (-1.7, 2.8)). Weight and height corrected for age were below normal (mean Z-score (range): -0.79 (-2.4, -0.05) and -1.2 (-2.8, 1.4) (P<0.01)). Lean body mass by skinfold sum (LBM(sfs)), UAC and BIA were also significantly below reference values (mean Z-score (range): -0.9 (-2.2, 1.8), -0.95 (-2.4, 1.8) and -1.1 (-3.6, 1.0) (P<0.01)). Lean body mass (LBM) by BIA correlated with LBM(sfs). BIA systematically underestimated LBM in both CF patients and in control subjects.

CONCLUSION

Nutritional status of children with CF must be evaluated, using age-corrected weight and height expressed in Z-score. LBM estimated by SFS, UAC and by BIA appear to be useful, although longitudinal studies in CF children should be performed to evaluate their clinical significance in detecting changes in nutritional status.

Growth in prepubertal children with cystic fibrosis, homozygous for the Delta F508 mutation

BACKGROUND AND METHODS

In cystic fibrosis, growth and lung function have been identified as prognostic markers of both severity of pulmonary disease and survival. Cross-sectional studies in patients with cystic fibrosis (CF) including all genotypes have shown that in prepubertal patients with lifetime continuous care within a specialised CF centre, growth can normalise. No corresponding improvement in lung function has been found. We used a longitudinal design to determine whether normalisation of growth could be found in the genetic subgroup of prepubertal children with CF with the homozygous Delta F508 mutation, which is one of the known severe mutations.

METHODS

Data of all children born after 1980 with the homozygous Delta F508 mutation, diagnosed in early childhood at the specialised centre of the Children's Hospital of Berne were systematically assessed up to the age of 11 years and retrospectively analysed. Follow-up data of height, weight and BMI were compared to the Swiss reference population using z-scores. The correlations between lung function parameters (FEV1, MEF50, VC) and age, as well as lung function parameters and growth indices, were calculated. Additionally, the same correlations were examined in a cohort with the same mutation born 10 years earlier.

RESULTS

In the study, cohort growth (height, weight and BMI) was significantly below that of the normal Swiss population. A significant decline of lung function with age was also found, however, no association between lung function and growth could be seen. Compared to an earlier cohort, an improved growth over the last decade could be shown but no improvement on lung function could be detected. Lung function varied widely in both groups.

CONCLUSION

In contrast to sequential cross-sectional studies of children with CF, the present longitudinal study of children with homozygous for the Delta F508 mutation failed to confirm normalisation of growth over time. However, compared to the data of children born in the previous decade, improved growth was observed.

Dietary intakes in adult patients with cystic fibrosis–do they achieve guidelines?

BACKGROUND

Most patients with cystic fibrosis (CF) require a higher energy and protein intake than their healthy peer group. There are few data on dietary intakes of adult patients. The aim of this study was to determine nutritional intakes in an adult population with CF. The impact of nutritional intervention and disease on macronutrient intake was examined.

METHODS

Retrospective cross-sectional analysis of 94 unweighed food diaries at annual review (1995-2000). Energy and protein intakes were compared to the estimated average requirement (EAR) for energy and reference nutrient intake (RNI) for protein. The effect of diet alone, oral supplements, enteral tube feeding, and cystic fibrosis related diabetes (CFRD), on macronutrient intake was examined and impact of pancreatic sufficency (PS) and lung transplantation.

RESULTS

Mean energy and protein intakes approached recommended CF guidelines, but in 72% of assessments these values were not achieved. Mean energy and protein intakes for patients on diet alone and protein intake for those with CFRD failed to meet recommendations. Oral supplementation and enteral tube feeding regimens increased energy and protein intake above recommended levels. No group achieved 40% total energy from fat. Patients receiving enteral tube feeds had the highest mean energy and protein intakes but lowest body mass index (BMI) and lung function.

CONCLUSION

Adequate mean energy and protein intakes in adult patients with CF mask subgroups of patients who fail to meet recommendations ie. diet alone, diabetic. Oral supplementation and enteral tube feeding increase energy and protein intake but fail to achieve an adequate BMI level in subjects with a decreased clinical status. Individual nutritional assessment remains essential.

Longitudinal changes in growth parameters are correlated with changes in pulmonary function in children with cystic fibrosis

OBJECTIVE

Nutritional status is associated with pulmonary health and survival in children with cystic fibrosis (CF). This study evaluated the weight gain pattern of children with CF in relation to the longitudinal trends of their pulmonary function. Our hypothesis was that children who experience continuous weight gain at a given rate will have better average forced expiratory volume in 1 second (FEV(1)) and change in FEV(1) than children who have weight gain patterns that deviate from this rate, even when total weight gain seems adequate.

METHODS

Prospectively collected data were examined in 319 children, aged 6 to 8, who were routinely followed at the Minnesota Cystic Fibrosis Center. One to 67 measurements of weight (kg), height (cm), and FEV(1) (mL) were taken per child during this 2-year period. The data were analyzed by repeated measure regression analysis and by growth pattern analysis.

RESULTS

At baseline, a 1-kg higher initial weight was associated with a 55-mL higher average FEV(1). During the follow-up period, a 1-kg gain in weight was associated with an increase in FEV(1) by 32 mL. Children who had a steady weight gain tended to experience greater increases in FEV(1) than children who experienced periodic losses in weight.

CONCLUSIONS

We established that children who weigh more and who gain weight at an appropriate and uninterrupted rate have a better FEV(1) trajectory. Aggressive nutritional support to maintain growth in these children may therefore improve FEV(1), which can be taken as a surrogate for better lung health, and may ultimately lead to better survival.

Cystic fibrosis-related diabetes

Diabetes mellitus (DM) has been recognized as a complication of cystic fibrosis (CF) for almost 50 years and commonly develops around 20 years of age. The prevalence increases with age and, with improved survival of those with CF, approaches 30% in certain centres. Its development appears to have a significant impact on pulmonary function and may increase mortality by up to six-fold. Subjects with CF are rarely ketosis-prone and phenotypically lie between Type 1 and Type 2 DM. Microvascular complications are recognized, although paucity of data does not permit a clear description of their natural history. An annual oral glucose tolerance test from the age of 10 years is recommended for screening, but logistical difficulties have led some groups to develop specific algorithms to aid diagnosis. Insulin sensitivity in CF is much debated and may depend upon the degree of glucose intolerance. Insulin resistance occurs in the presence of infection, corticosteroid usage and hyperglycaemia, whilst hepatic insulin resistance is considered an adaptation to CF. There is no universal consensus on the treatment of hyperglycaemia. With increased longevity of individuals with CF, greater numbers will develop diabetes and the diabetes physician is destined to play a greater role in the multidisciplinary CF team.

Relationship between nutritional status and lung function in cystic fibrosis: cross sectional and longitudinal analyses from the German CF quality assurance (CFQA) project

BACKGROUND

The German cystic fibrosis (CF) quality assurance (CFQA) project is a patient registry for CF which was founded in 1995. Relevant clinical and laboratory data, respiratory function test results, complications, and CF treatments are entered into the database once a year for each patient. Using the database, a study was undertaken to elucidate the relationship between nutrition and lung function in a large patient cohort by cross sectional and longitudinal analysis.

METHODS

A cohort of 3298 patients above 2 years of age was analysed. Patients were grouped according to the presence or absence of malnutrition (wasting and/or stunting). Cross sectional and longitudinal analyses over 2 and 3 years including mixed model analyses were performed.

RESULTS

The prevalence of abnormal weight for height (<90% predicted) increased with age from 19% in children aged <6 years to 38% in adults with CF. Patients with malnutrition had significantly lower mean values of vital capacity, arterial oxygen tension (PO(2)), and forced expiratory volume in 1 second (FEV(1)) and higher serum IgG (p<0.05). Pseudomonas aeruginosa infection was also associated with decreased pulmonary function. Malnourished adolescents aged 12-18 years experienced a serious decline in FEV(1) of about 20% predicted, whereas mean FEV(1) values remained stable at above 80% predicted in adolescents of normal weight. Longitudinal follow up showed that malnourished patients of all ages and those with P aeruginosa infection had significantly worse lung function than their normally nourished counterparts and a greater yearly loss of FEV(1) % predicted. During 1 year of observation adolescents who experienced a >5% predicted decrease in weight for height had a concomitant mean loss of FEV(1) of 16.5% predicted during that year, whereas patients who gained relative weight had a parallel increase in FEV(1) of 2.1% predicted.

CONCLUSIONS

These data emphasise the close relationship between nutrition, lung function, and clinical course in CF. Normal body weight and absence of P aeruginosa infection was associated with better preservation of lung function.

Estado nutricional e ingestão alimentar de pessoas com fibrose cística

A mucoviscidose é uma doença que afeta o estado nutricional por interferir na ingestão e absorção adequadas de nutrientes. Este estudo avaliou 22 pacientes mucoviscidóticos atendidos no Ambulatório de Nutrição do Hospital Infantil Joana de Gusmão em Florianópolis, SC, no período de agosto de 1998 a janeiro de 1999. O estado nutricional foi determinado através de medidas antropométricas e dados de consumo alimentar. Quanto ao estado nutricional, 42,9% dos menores de 2 anos e 28,6% dos maiores de 10 anos estavam desnutridos; na faixa etária de 2 a 10 anos não houve nenhuma criança desnutrida. Quanto ao consumo alimentar, 33,3% atingiram a recomendação de energia e 95,2% atingiram a recomendação de proteína. Podemos concluir que a mucoviscidose afeta o estado nutricional das crianças em períodos críticos de crescimento e desenvolvimento, e que a qualidade da dieta destes pacientes pode ser melhorada através de um cuidado nutricional adequado.

Total energy expenditure in stable patients with cystic fibrosis

BACKGROUND AND AIMS

Undernutrition is a common problem in patients with cystic fibrosis and is associated with a poor prognosis. The two aims of this study were to assess and compare the two main field techniques in the measurement of total energy expenditure and, secondly, to assess total energy expenditure in stable patients and compare with healthy controls.

METHODS

Resting energy expenditure was measured using indirect calorimetry and total energy expenditure was measured using 24-h heart rate (HR) methodology and doubly isotopically labelled water.

RESULTS

Seventeen patients, mean age 23 years and FEV(1)52% predicted and thirteen controls were recruited. Resting energy expenditure was higher in patients 0.24 (0.03) MJ/kg Fat-Free Mass (FFM) compared to controls 0.22 (0.02) MJ/kg FFM, P=0.02. Twenty-four hour heart rate underestimated total energy expenditure, 9.49 (1.85) MJ/day in patients compared to 11.69 (2.79) MJ/day using doubly labelled water. There was no difference in total energy expenditure in patients and controls using both methods, 11.69 (2.79) MJ/day compared to 11.38 (2.71) MJ/day using doubly isotopically labelled water.

CONCLUSIONS

In clinically stable young adult patients with moderately severe respiratory disease total energy expenditure is comparable to that an a control population despite in increase in resting energy expenditure and both 24-h HR and doubly isotopically labelled water are suitable for use in patients with cystic fibrosis.

Changes in strategies for optimal antibacterial therapy in cystic fibrosis

Aggressive antibiotic therapy of bacterial airway infection is one of the main reasons for the dramatic increase in life expectancy over the last few decades. Staphylococcus aureus and Haemophilus influenzae are the predominant pathogens in younger patients, but the choice of antibiotic therapy against these pathogens remains highly controversial. There is general agreement that patients with pulmonary exacerbations should be treated and many cystic fibrosis (CF) centres will also try to eradicate bacteria in the absence of symptoms. Prophylactic antibiotic therapy, with anti-staphylococcal medications started at the time of diagnosis, is advocated by some groups but its positive effect remains unproven. In fact, recent studies have suggested that continuous prophylactic treatment with anti-staphylococcal antibiotics may increase the risk of early colonisation with Pseudomonas aeruginosa. P. aeruginosa is the main pathogen in older children with CF. While chronic airway infection with mucoid P. aeruginosa is considered irreversible, both the combination of oral ciprofloxacin with inhaled colistin and inhaled tobramycin alone has been used successfully in the early phase of colonisation. In patients chronically infected with P. aeruginosa, standard treatment of pulmonary exacerbations consists of intravenous combination therapy for 2-3 weeks. Controversy exists whether this treatment should be performed routinely every 3 months or only in the presence of a pulmonary exacerbation. Inhaled antibiotics such as tobramycin have been shown to improve lung function and reduce sputum density of P. aeruginosa, but both the optimal dose and the duration of therapy are unclear at the present time.

European Epidemiologic Registry of Cystic Fibrosis (ERCF): comparison of major disease manifestations between patients with different classes of mutations

SUMMARY. By August 1997, 11,749 patients with cystic fibrosis had been enrolled in the European Epidemiologic Registry of Cystic Fibrosis (ERCF). Genotype analysis had been performed on 8,963 (76%) of these patients, and the majority had one or two identifiable mutations. Patients with known mutations were classified according to the type of mutation (Classes I-V), and were grouped according to the class of mutation on both chromosomes. This resulted in six subgroups, including all patients homozygous for Class I (I/I, n = 72), for Class II (II/II, n = 5,020), and for Class III mutations, (III/III, n = 23). Since there were only 23 patients homozygous for Class III mutations, a fourth group was made up of patients who were compound heterozygous for a Class II and III mutation (II/III, n = 265). There were only five patients homozygous for Class IV mutations, and consequently a fifth group was made up of all patients carrying at least one Class IV mutation, regardless of the nature of the mutation on the other chromosome (IV/any, n = 187). None were homozygous for Class V mutations; consequently, a sixth group consisted of patients carrying at least one Class V mutation (V/any, n = 22). Mean age was highest in groups III/III, IV/any, and V/any (15.6, 16, and 17 years, respectively) as opposed to 12.4 years in group II/II and 13.4 in group II/III, but both group III/III and V/any were small, and the confidence interval of the mean was large. The percentage of patients receiving pancreatic enzymes was lower in groups IV/any and V/any than in any of the other groups, i.e., approximately 50% of patients 18 years or older in both groups as opposed to between 90-100% of all other patients regardless of age. The prevalence of diabetes mellitus increased with age from 2.6% in patients < 18 years to 22.1% in patients 18 years or older in the large group II/II, but was only 1.5% in patients 18 years or older in group IV/any. Disregarding the small group III/III, abnormally elevated liver enzymes and/or bilirubin (1.5 x upper normal limit) was much less frequent in group IV/any than in any of the other groups, both overall and in patients aged 18 years or more. The course of lung disease appeared to be less dependent on genotype than pancreatic function, with only minor differences between groups; however, the mean values of both FVC % and FEV(1) % were slightly higher in group IV/any than all other groups in both younger and older patients. The same was found for the prevalence of some major clinical signs of severe lung disease, such as clubbing, hyperinflation, and crepitations. Overall mean weight expressed as an age percentile was markedly higher in group IV/any than in any other group, which may be related to the finding of a much lower prevalence of chronic P. aeruginosa infection in patients 18 years or older belonging to group IV/any (and V/any) than in any other group. In conclusion, the presence of a class IV mutation appears to offer some degree of protection against pancreatic insufficiency, diabetes mellitus, and liver disease. We confirmed that lung disease follows a milder clinical course in patients with a class IV mutation and that the presence of a class IV mutation (and possibly class V) is associated with a delay in the onset of P. aeruginosa infection.

Prospective evaluation of growth, nutritional status, and body composition in children with cystic fibrosis

BACKGROUND

Several cross-sectional studies have shown improvement in the growth of children with cystic fibrosis (CF) because of increased awareness of and more comprehensive care of their special nutritional needs. However, longitudinal data on the nutritional status of these children are rare.

OBJECTIVE

The objective was to compare changes in growth, body composition, and nutritional status between children with and without CF.

DESIGN

This was a prospective 3-y cohort study of 25 children aged 5-10 y with CF, mild pulmonary disease, and pancreatic insufficiency and of 26 healthy control children. Three methods were used to assess body composition: measurements of skinfold thickness, total body water by deuterium oxide, and total-body electrical conductivity. Growth and body-composition changes over time were analyzed by a longitudinal mixed-effects model.

RESULTS

Over the 3 y of the study, the statural growth of the boys with CF was slower than that of the control subjects (P = 0.004). The same divergence over time between the boys with and without CF was observed for fat-free mass assessed by skinfold-thickness measurements and total body water (P = 0.008 and 0.02, respectively) and for fat mass assessed by skinfold-thickness measurements and total-body electrical conductivity (P = 0.009 and 0.001, respectively). The differences in the pattern of changes in growth and body composition were less striking for girls.

CONCLUSIONS

Despite comprehensive care, the growth of boys with CF was impaired on the basis of height, fat-free mass, and fat mass, when observed longitudinally. Caution should be used when interpreting cross-sectional measurements because they often do not detect suboptimal growth.

Elective versus symptomatic antibiotic treatment in cystic fibrosis patients with chronic Pseudomonas infection of the lungs

BACKGROUND

A previous retrospective study suggested that a policy of regular anti-pseudomonal antibiotic treatment improved pulmonary function and increased survival in patients with cystic fibrosis chronically infected with Pseudomonas species. The results of a prospective multicentre study to compare the effects on pulmonary function and mortality of three monthly elective anti-pseudomonal antibiotic treatment with conventional symptomatic treatment are reported.

METHODS

Sixty patients with cystic fibrosis, chronically infected with P aeruginosa, were randomised to the two treatment arms (elective or symptomatic) and followed clinically at yearly reviews. The major end points were changes in forced expiratory volume in one second (FEV(1)) and forced vital capacity (FVC). Survival was a secondary end point.

RESULTS

Patients in the symptomatic group received a mean of three antibiotic treatments each year and those in the elective group received four antibiotic treatments during each year of the study. No significant differences in FEV(1) and FVC were found between the two groups after three years. There was a statistically non-significant higher rate of deaths in the elective group (n = 4), three of which were associated with B cepacia infection, compared with the symptomatic group (n = 0).

CONCLUSIONS

This study did not demonstrate an advantage of a policy of elective antibiotic treatment over symptomatic treatment in patients with cystic fibrosis chronically infected with Pseudomonas species.

Nutritional status of an adult cystic fibrosis population

Nutritional management and dietary recommendations in patients with cystic fibrosis (CF) have changed considerably over the past 10-15 y. The nutritional status of adult CF patients was assessed in a clinical survey before these changes in nutritional management. The aim of the study was to assess the current nutritional status of the CF population and compare the results with those of the previous study. Forty-three (24 male, 19 female) subjects participated in this study. Subjects' height, weight, mid-upper-arm circumference, and skinfolds at four sites were measured. Nutritional intake was measured by using a 7-d food intake diary including documentation of supplements taken. Compared with the 1983 study, the incidence of malnutrition, as indicated by a body mass index of less than 20, has decreased from 62% to 9%. Furthermore, there have been significant improvements in the weight, height, and body mass index of both males (P < 0.001) and females (P < 0.04). Individuals with CF are no longer subject to growth arrest, as their mean height is now comparable to the Australian average. Mid-upper-arm circumference (P < 0.0001), triceps skinfold (P < 0.0001), and percentage of body fat (P < 0.05) of males and females have also significantly increased. The fat intake (P < 0.02) of females and males and energy intake (P < 0.03) of females have increased significantly, and the mean energy intake of subjects has exceeded the recommended 120% of the recommended daily intake. A significant number of patients in the present study receive dietary oral and/or enteral supplements. Multiple linear regression analysis indicated that nutritional management was principally responsible for improvements in nutritional status. The findings suggest that there has been a significant improvement in the nutritional status of the adult CF population, which may be due primarily to changes in nutritional management.

Nutritional imperatives in cystic fibrosis therapy

Patients with CF who receive optimal nutrition have better growth, maintain better nutritional reserves, and have better pulmonary function than patients with CF who have poor nutrition. These factors influence quality of life as well as survival. The metabolic and immunologic response to infection, as well as the increased work of breathing, escalates calorie requirements in this patient population. No single strategy works for every patient. Therefore, close monitoring of growth, symptoms, and changes in respiratory status that could increase calorie requirements is necessary.

Nutrition in adults with cystic fibrosis

Improved survival has been associated with better nutritional status in patients with cystic fibrosis (CF). In this study we examined the relationship between nutritional state and other measures of clinical severity in adult patients with CF, attending a regional centre. Eighty-one patients (median age 21 years) were studied. Patients with CF were significantly under weight, compared to healthy individuals but were of similar height. Measurements of lung function, FEV1 and FVC were significantly related to body mass index. Lung function was poorer in patients with chronic pseudomonal infection but body weight and body mass index were not significantly different compared to those without such infection. In 53 patients who were alive 4 years later, FEV1 had declined by -10.5 (2.1)% (P < 0.001) but there was no significant change in body weight 1.5 (6.5) kgs. In 23 patients who died or had lung transplantation the change from 1994 to the date of death or transplantation the FEV1 was reduced by -7.9 (11.2)% (P = 0.004) and body weight -2.8 (4.4) kgs (P < 0.01). In 12 patients who had supplemental enteral feeding, the median increase in body weight was 7|kgs over a period of 12 months. This study confirms that young adult patients with CF are significantly under weight and declining health is associated with significant weight loss. In patients with severe malnutrition significant improvement can be achieved by enteral feeding.

Fasting in healthy individuals and adaption to undernutrition during chronic disease

During long-term fasting, gluconeogenesis from amino acids was thought to lessen, when ketone bodies from lipolysis became a major fuel source. Thus, muscle mass is conserved. However, recent studies show that this adaptation does not occur in chronic undernourishment. In cancer, chronic undernutrition without disease, and HIV infection, carbohydrate utilization is high. Enhanced hepatic glucose production occurs in active inflammatory bowel disease and in underweight cancer patients. Repletion of tissue after undernutrition is energetically inefficient because of enhanced diet induced thermogenesis (following anorexia nervosa) and decreased fat, and increased protein, oxidation (in tuberculosis).