Background: Undernutrition is common in patients with cystic fibrosis (CF). Nutritional rehabilitation has been shown to improve linear growth, pulmonary function, well-being, and resistance to infection in this population. The purpose of this study was to determine whether the administration of megestrol acetate (MA) induces weight gain in malnourished patients with CF, and to assess the composition of weight gain.
Methods: In a randomized, placebo-controlled, double-blind, crossover study, 12 children with CF received MA (10 mg/kg/d) or placebo for 12 weeks, followed by a 12-week washout period, then the alternative treatment. Anthropometrics, caloric intake, and clinical assessment were obtained every 6 weeks; pulmonary function tests, biochemistry, hematology, cortisol, growth hormone, insulin, C-peptide, insulin-like growth factor-1, insulin-like growth factor binding protein-3, and dual-energy x-ray absorptiometry scans were obtained every 12 weeks.
Results: Six children did not complete the study, three for reasons unrelated to the study, two because they developed diabetes while receiving MA, and one who had glucose intolerance while receiving the placebo. Average weight gain was 3.05 kg in the MA group and 0.3 kg in the placebo group. The change in weight z score was +0.76 in the MA group and -0.05 in the placebo group. The change in height z score was -0.06 in the MA group and +0.06 in the placebo group. Lean body mass and body fat increased by 1507 g and 1192 g respectively in the MA group. Pulmonary function tests improved in the MA group; serum cortisol levels decreased. Side effects included glucosuria, insomnia, hyperactivity, and irritability.
Conclusions: Weight, body fat, and lean body mass increased and pulmonary function improved in the children with CF given MA. Adrenal suppression, glucose intolerance, and diabetes are side effects.