Hui Chuan Lai

Risk of persistent growth impairment after alternate-day prednisone treatment in children with cystic fibrosis

BACKGROUND It is uncertain whether the growth impairment that occurs in children during long-term treatment with glucocorticoids persists after the medication is discontinued and ultimately affects adult height. METHODS We evaluated growth six to seven years after alternate-day treatment with prednisone had been discontinued in 224 children 6 to 14 years of age with cystic fibrosis who had participated in a multicenter trial of this therapy from 1986 through 1991. Of the children, 151 had been randomly assigned to receive prednisone (either 1 or 2 mg per kilogram of body weight) and 73 to receive placebo. We obtained data on growth up to 1997 from the Cystic Fibrosis Foundation Patient Registry and standardized the data to sex- and age-specific norms from the National Center for Health Statistics. We used z scores to compare growth patterns among treatment groups. RESULTS In 1997, 68 percent of the patients were 18 years of age or older. The z scores for height declined during prednisone therapy; catch-up growth began two years after treatment with prednisone was discontinued. Among the boys, the z scores for height in those treated with prednisone remained lower than the scores for those who received placebo (P=0.02). The mean heights for boys 18 years of age or older were 4 cm less in the prednisone groups than in the placebo group, an equivalent of 13 percentile points (P=0.03). Among the girls, differences in height between those who were treated with prednisone and those who received placebo were no longer present two to three years after prednisone therapy was discontinued. CONCLUSIONS Among children with cystic fibrosis who have received alternate-day treatment with prednisone, boys, but not girls, have persistent growth impairment after treatment is discontinued.

Nutritional status of patients with cystic fibrosis with meconium ileus: a comparison with patients without meconium ileus and diagnosed early through neonatal screening.

Objective. This study was pursued as an extension of a randomized clinical investigation of neonatal screening for cystic fibrosis (CF). The objective was to determine if CF patients with meconium ileus (MI) were more likely to be malnourished compared with those without MI who were diagnosed during early infancy through neonatal screening. Methodology. Nutritional status was evaluated from early infancy to 13 years of age based on anthropometric, biochemical, and dietary assessments. Results. MI patients (n = 32) were smaller at birth (3117 g compared with 3413 g) and were shorter (22nd percentile compared with 48th percentile) and thinner (24th percentile compared with 49th percentile) compared with non-MI early diagnosed patients (n = 50) up to 13 years of age. Poor growth was particularly evident in 26 MI patients who required surgery for MI (height and weight at the 20th percentile), whereas those treated without surgery (n = 6) showed better height (45th percentile) and weight (37th percentile). Abnormal essential fatty acid profiles were significantly more prevalent in MI compared with non-MI early-diagnosed patients before 3 years of age. Daily intakes of calorie (130% compared with 111% recommended dietary allowances) and protein (339% compared with 279% recommended dietary allowances) were higher but the percentage of fat (37% compared with 38%) and linoleic acid (4.5% compared with 4.7%) in the diet were similar between the two groups. Conclusions. These results demonstrated a clear association of MI with malnutrition in CF. The observed poor growth among our MI patients was not because of poor dietary intakes, but was related to surgical treatment for MI and poor essential fatty acid status. These findings present new challenges regarding the optimal medical treatment and nutritional intervention for CF patients with MI.

Temporal Associations Among Energy Intake, Plasma Linoleic Acid, and Growth Improvement in Response to Treatment Initiation After Diagnosis of Cystic Fibrosis

OBJECTIVE. It is unclear why some patients with cystic fibrosis (CF) succeed (“responders”) in recovering from malnutrition and growth faltering after treatment initiation whereas others fail to do so (“nonresponders”). We conducted a study to test the hypothesis that sustained high energy intake (↑EN) and normal plasma essential fatty acid status are critical determinants of treatment responsiveness within 2 years after diagnosis of CF. METHODS. A total of 71 CF children who had pancreatic insufficiency but not meconium ileus and were enrolled in the Wisconsin CF Neonatal Screening Project were studied. Responders were defined by having achieved adequate weight gain, as indicated by a recovery of weight z score (Wtz) comparable to Wtz at birth (WtzBR) within 2 years of diagnosis. ↑EN and sustained normal plasma linoleic acid level (↑pLA) were defined by achieving energy intake ≥120% of estimated requirement for ≥75% of the time and maintaining plasma LA ≥26% of total fatty acids for ≥75% of the time, respectively. RESULTS. Thirty-two (68%) screened patients and 13 (54%) patients whose CF was diagnosed conventionally recovered WtzBR within 2 years of diagnosis. Screened patients responded at significantly younger ages (mean/median: 6.3/4.3 months) than patients whose CF was diagnosed conventionally (mean/median: 15.8/11.8 months). Proportionately fewer screened patients (33%) achieved ↑EN compared with patients whose CF was diagnosed conventionally (73%). However, more screened patients responded to ↑EN and recovered WtzBR (91%) than patients whose CF was diagnosed conventionally (56%), although this difference was of borderline significance. Compared with having neither ↑EN nor ↑pLA, the likelihood of being a responder was greatest with combined ↑EN and ↑pLA, followed by ↑EN only. The positive associations between ↑EN and ↑pLA to treatment responsiveness remained significant after adjustment for neonatal screening status, baseline height and weight status, and indices of pulmonary disease severity. CONCLUSION. ↑EN and ↑pLA are critical in promoting adequate weight gain in children with newly diagnosed CF.