J.W. Woestenenk

Constipation in pediatric Cystic Fibrosis patients: An underestimated medical condition

BACKGROUND The aims of this study were to determine prevalence, risk factors and treatment of constipation in patients with Cystic Fibrosis (CF), as well as the diagnostic value of abdominal radiography. METHODS A cohort of 214 pediatric CF patients was investigated. Furthermore, 106 abdominal radiographs of CF patients with or without constipation were independently assessed by three observers on two separate occasions using the Barr and Leech scores. RESULTS The prevalence of constipation was 47%. Low total fat absorption and meconium ileus were independent risk factors for constipation in CF, while fiber and fluid intake were not associated. In CF patients the inter and intraobserver variabilities of the Barr and Leech scores were poor to moderate. CONCLUSION Constipation is a significant medical issue in CF and was associated with low total fat absorption and a history of meconium ileus. Finally, abdominal radiography seems of little value in the regular follow-up of CF patients.

Nutritional intervention in patients with Cystic Fibrosis: A systematic review

BACKGROUND To systematically assess the literature published after 1997 describing the effectiveness of nutritional interventions in Cystic Fibrosis patients. METHODS An online search in PUBMED, EMBASE and COCHRANE databases was conducted. Original studies with 4 patients or more, describing a nutritional intervention and giving at least weight as an outcome parameter were included. RESULTS The inclusion criteria were met by 17 articles, focusing on respectively behavioural interventions (n=6), oral supplementation (n=4) or enteral tube feeding (n=7). This latter intervention was universally successful to induce weight gain. One behavioural study and 2 oral supplementation studies also reported significant weight gain. CONCLUSION Enteral tube feeding is effective to improve nutritional status, while the described effects of behavioural intervention and oral supplementation are not consistent at present.

Dietary intake in children and adolescents with cystic fibrosis.

BACKGROUND & AIMS The recommendation for caloric intake in CF patients is to obtain intakes between 110 and 200% of the estimated average requirement (EAR) for age groups and gender, of which 35-40 energy% should be from fat. It is questionable whether the advice is met. METHODS 1726 Completed 3-day dietary food records of 234 CF patients (111 girls) and 2860 completed two non-consecutive 24-h dietary assessments of healthy controls (1411 girls) were studied. The dietary intake in CF patients was compared with that of healthy controls by using independent sample t tests. RESULTS Caloric intake in children with CF varied highly with age (88-127% EAR), which is below or in the lower range of the recommended 110-200% EAR. However the absolute caloric intake in CF children was significantly higher compared to controls at all ages. In addition, apart from boys aged 1-3 years, all CF children had a fat intake of 35 energy% or more. This fat intake was significantly higher than in controls, as was the consumption of saturated fat, the latter being well above 10% of the total energy intake. CONCLUSION Although CF patients generally do not meet the EAR recommendations, they had a significantly higher caloric intake than controls. Moreover fat intake in CF patients does generally meet recommendations, but this resulted in a considerable consumption of saturated fat; a reduction of the latter seems appropriate.

Pancreatic Enzyme Replacement Therapy and Coefficient of Fat Absorption in Children and Adolescents With Cystic Fibrosis.

Objectives: Pancreatic enzyme replacement therapy (PERT) is the proven therapy to substantially reduce fat malabsorption in patients with cystic fibrosis (CF). Few details of the daily practice regarding PERT and the resulting coefficient of fat absorption (CFA) are known. We therefore recorded the PERT and CFA in a large cohort of pancreatic insufficient pediatric patients with CF. Methods: We retrospectively studied 1719 completed 3-day dietary food records, including the pancreatic enzyme intake registrations, and 1373 CFA assessments of 224 patients with CF, ages 0–17 years. The clinical characteristics, PERT, expressed as an intake of lipase unit (LU) per gram of fat per day and LU per kilogram per day, and the CFA were described for the group as a whole and separately for those on enteral tube feeding. Cross-sectional relationship between the CFA and the LU per gram of fat per day and LU per kilogram per day were determined for each year of age. We also addressed the effect of the interventions done in patients with CFA outcomes <85%. Results: The LU per gram of fat per day was relatively stable throughout the age groups, whereas the LU per kilogram per day fell markedly with age. The median CFA in the age group 17 varied between 86% and 91%, however, with a CFA below 85% in 325 of 1373 (24%) of the measurements. No relationship was found between PERT and CFA. The patients with persistent CFA less than 85% had significant lower z scores weight for age and weight for height (P = 0.01) than those with CFA at least 85%. Conclusions: In this study population, no correlation between an enzyme dosage and the degree of fat malabsorption was found; however, a CFA below 85% was found in 24% of the measurements.

The relationship between body growth and pulmonary function in children with cystic fibrosis

To measure the weight and height of children with cystic fibrosis (CF) from 2 to 10 years of age and to investigate the relationship between these parameters and forced expiratory volume in 1 sec (FEV1) beginning at 6 years of age.

Comparison of height for age and height for bone age with and without adjustment for target height in pediatric patients with CF

BACKGROUND Height is a strong prognostic factor in cystic fibrosis (CF) and is usually compared to reference values of healthy children by expressing height as a z-score height-for-age (HFA). However, HFA does not take into account a potential delay in bone age (BA) and the genetic potential of the child and could therefore result in misclassification of short stature. METHODS In 169 children with CF height, BA and target height (TH) were assessed. HFA, height for bone age (HBA), HFA adjusted for target height (HFA/TH) and HBA adjusted for target height (HFA/TH) were determined and children were categorized according to these four methods. RESULTS Mean z-scores of the four methods ranged from -0.1 ± 0.8 (HBA/TH) to -0.5 ± 1.0 (HFA). Prevalence of short stature (z-score <-2 SD) determined by HFA (8%, n=14) was higher than when HBA, HFA/TH (both 5%, n=8) and HBA/TH (1% n=1) were applied. CONCLUSION The method used to classify height affects outcome on a group level and for individual patients. Target height and bone age are likely to have added value in the interpretation of height in patients with CF.

Vitamin e intake, α-tocopherol levels and pulmonary function in children and adolescents with cystic fibrosis

Pancreatic insufficiency cystic fibrosis (CF) patients receive vitamin E supplementation according to CF-specific recommendations in order to prevent deficiencies. It has been suggested that higher serum α-tocopherol levels could have protective effects on pulmonary function (PF) in patients with CF. Whether current recommendations are indeed optimal for preventing deficiency and whether vitamin E has therapeutic benefits are subjects of debate. Therefore, we studied vitamin E intake as well as the long-term effects of vitamin E intake, the coefficient of fat absorption (CFA) and IgG on α-tocopherol levels. We also examined the long-term effects of serum α-tocopherol and serum IgG on forced expiratory volume in 1 s expressed as percentage of predicted (FEV₁% pred.) in paediatric CF patients during a 7-year follow-up period. We found that CF patients failed to meet the CF-specific vitamin E recommendations, but serum α-tocopherol below the 2·5th percentile was found in only twenty-three of the 1022 measurements (2 %). Furthermore, no clear effect of vitamin E intake or the CFA on serum α-tocopherol was found (both P≥ 0·103). FEV₁% pred. was longitudinally inversely associated with age (P< 0·001) and serum IgG (P= 0·003), but it was not related to serum α-tocopherol levels. We concluded that in the present large sample of children and adolescents with CF, vitamin E intake was lower than recommended, but serum α-tocopherol deficiency was rare. We found no evidence that higher serum α-tocopherol levels had protective effects on PF. Adjustment of the recommendations to the real-life intake of these patients may be considered.

Height Assessment in the Dutch-Origin Pediatric Cystic Fibrosis Population

Background: Height evaluation is an integral part of cystic fibrosis (CF) care. Height is compared with reference values by converting it to height-for-age (HFA) z scores. However, HFA z scores do not adjust for genetic potential (ie, target height [TH]), which could result in an incorrect estimation of the height. Materials and Methods: To evaluate the magnitude of this potential problem, we assessed the agreement between HFA and HFA-adjusted-for-TH (HFA/TH) z scores in 474 Dutch children with CF. Results: In this study sample, HFA z scores were −0.07 (95% confidence interval, −0.02 to −0.12) lower than HFA/TH z scores. When HFA and HFA/TH z scores were subdivided into 4 categories (≥0, <0 and ≥–1, <−1 and ≥−2, and ⩽−2), a moderate agreement was found. HFA z scores were classified lower than HFA/TH z scores in 21% of the measurements and higher in 15% of the measurements. Conclusion: In clinical routine, height evaluation based on HFA may result in underestimation or overestimation of height growth, which may induce inappropriate nutrition interventions.

Dietary intake and lipid profile in children and adolescents with cystic fibrosis

BACKGROUND Cystic fibrosis (CF) patients are advised to derive 35% of their daily energy intake from dietary fat. Whether this high fat intake is associated with dyslipidaemia is unknown. We described the lipid profile and dietary intake in paediatric patients with CF. METHODS 110 fasting lipid concentrations of 110 Dutch patients with CF were studied, along with 86 measurements of dietary intake. For the total group and for boys and girls separately, the lipid profile and the dietary intake were investigated. The cross-sectional relationship between the lipid concentrations and dietary intake was determined. RESULTS The mean dietary fat intake was ≥35% of the total energy intake, along with a considerable consumption of saturated fat. We found lower concentrations of cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol, and increased concentrations of triglyceride and triglyceride to high-density lipoprotein cholesterol ratios. Lipid concentrations were not associated with dietary fat intake. CONCLUSION This study lacks variation in dietary fat intake to exclude an effect on lipid concentrations as the distribution of dietary fat intake remained constant at a high level. Elevated triglyceride concentrations and triglyceride to high-density lipoprotein cholesterol ratios suggest an increased risk of cardiovascular disease. Any negative consequences of a high dietary fat intake on the overall lipid profile later in life cannot be excluded.

Serum retinol levels and pulmonary function in children and adolescents with cystic fibrosis

Abstract Background It has been suggested that higher serum retinol levels could have protective effects on pulmonary function (PF) in patients with cystic fibrosis (CF). However, serum retinol levels will be transiently decreased during pulmonary exacerbation. Therefore, the extent of chronic pulmonary inflammation should be included when describing the association between PF and serum retinol. We assessed the longitudinal relation between serum retinol, immunoglobulin G (IgG) and PF in paediatric CF patients. Methods We studied the serum retinol, IgG and forced expiratory volumes in one second (FEV 1 % pred.) of 228 CF patients during a seven-year follow up period. The cross-sectional and longitudinal relations between these variables were assessed. Results Serum retinol, with medians levels between 1.2 and 1.4μmol/l, were relatively stable, while median serum IgG gradually increased during the age years. The FEV 1 % pred. was longitudinally inversely associated with serum IgG and age, but not with serum retinol. Each g/l increase in serum IgG level was associated with an accelerated yearly decline in FEV 1 % pred. of 0.5% (95% CI −0.8 to −0.1, p =0.008), and each year increase in age was associated with a 1.7% (95% CI −2.1 to −1.3, p =0.000) decline in FEV 1 % pred. This effect was not observed with respect to serum retinol levels (95% CI −1.9 to 2.2, p =0.570). Conclusions In this large sample of children and adolescents with CF, we found no evidence that higher serum retinol levels had protective effects on PF.