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

BACKGROUND: The study aim was to determine the effect of a dietary intervention on growth, body composition and resting energy expenditure (REE) in children with cystic fibrosis (CF) and pancreatic insufficiency (PI) in a randomized, double blind, placebo-controlled trial. METHODS: Subjects (5 to 17 yrs) participated in a 12-month trial of the organized lipid matrix LYM-X-SORB™ (LXS) vs. placebo dietary supplements with similar calories, total fat and fatty acids. Dietary intake was assessed using 3-day weighed food records. Height (HAZ), weight (WAZ), BMI (BMIZ), mid-upper arm muscle (UAMAZ) and fat area (UAFAZ) Z-scores were calculated. Fat mass (FM) and fat-free mass (FFM) were obtained by whole body DXA. REE (kcal/d) was evaluated by indirect calorimetry at baseline, 3 and 12 months and %REE calculated using Schofield equations. No growth or REE differences were observed between LXS and placebo groups so data were pooled for analysis. RESULTS: 63 children (57% males, age 10.6 ± 2.9 yr, 43% receiving LXS) completed REE measurements. Caloric intake increased from a median of 2502 [1478, 4909] to 2616 [1660, 4125] kcal/d at 12 months. HAZ, WAZ and UAMAZ increased (p < 0.05) over 12 months. Mean REE was 109 ± 8% predicted at baseline and 107 ± 9% at 12 months (p < 0.05). REE (kcal/d) adjusted for FFM and FM decreased over 12 months ([mean ± SE] -31 ± 12 kcals, p < 0.01), significant only in males (-49 ± 16 kcals, p < 0.01). CONCLUSIONS: Over a 12 month nutrition intervention with either LXS or placebo, the growth status, muscle stores and REE improved. Sustained increased energy intake improved energy metabolism, growth and nutritional status in school age children with CF, PI and mild lung disease.

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

OBJECTIVES: The aim of the study was to assess the impact of LYM-X-SORB (LXS), an organized lipid matrix that has been shown to be absorbable without pancreatic enzyme therapy on fat-soluble vitamin status in children with cystic fibrosis (CF) and pancreatic insufficiency (PI). METHODS: Children with CF and PI were randomized to daily LXS or an isocaloric placebo comparison supplement for 12 months. Serum vitamins A (retinol), D (25-hydroxyvitamin D[25D]), E (α-tocopherol, α-tocopherol:cholesterol ratio), and K (percentage of undercarboxylated osteocalcin [%ucOC] and plasma proteins induced by vitamin K absence factor II [PIVKA II]) were assessed at baseline and 12 months. Dietary intake was determined using 3-day weighed food records and supplemental vitamin intake by a comprehensive questionnaire. RESULTS: A total of 58 subjects (32 boys, age 10.3 ± 2.9 years [mean ± standard deviation]) with complete serum vitamin, dietary and supplemental vitamin data were analyzed. After adjusting for dietary and supplemental vitamin intake, serum retinol increased 3.0 ± 1.4 µg/dL (coefficient ± standard error) (adjusted R2 = 0.02, P = 0.03) and vitamin K status improved as demonstrated by a decreased percentage of undercarboxylated osteocalcin of -6.0% ± 1.6% by 12 months (adjusted R2 = 0.15, P < 0.001). These changes occurred in both the LXS and placebo comparison groups. No changes in serum 25D or α-tocopherol were detected. Both nutrition interventions increased caloric intake a mean of 83 ± 666 kcal/day by 12 months. CONCLUSIONS: Vitamins A and K status improved, whereas vitamins D and E status was unchanged during 12 months of LXS and isocaloric placebo comparison supplement in children with CF and PI.