The effects of an intensive behavior and nutrition intervention compared to standard of care on weight outcomes in CF

Inadequate intake and suboptimal growth are common problems for patients with CF and a critical target for intervention. The purpose of this study was to compare the growth outcomes of children with CF who participated in a randomized clinical trial to improve energy intake and weight to children with CF receiving standard of care during the same time period. Our primary outcome was change in body mass index z-score (BMI z-score) over 2 years. An exploratory outcome was forced expiratory volume at 1-sec (FEV₁) over 2 years. Participants were children ages 4-12 with CF, who participated in a randomized clinical trial of behavior plus nutrition intervention versus nutrition education alone, and a matched Comparison Sample receiving standard of care drawn from the Cystic Fibrosis Foundation (CFF) Registry. Children in the Clinical Trial Group (N = 67) participated in a 9-week, nutrition intervention and were followed at regular intervals (3, 6, 12, 18, and 24 months) for 2 years post-treatment to obtain anthropometric and pulmonary function data. For each child in the Comparison Sample (N = 346), these measures were obtained from the CFF Registry at matching intervals for the 27-month period corresponding to the clinical trial. Over 27 months, children in the Clinical Trial Group (the combined sample of the behavior plus nutrition and the nutrition alone) demonstrated significantly less decline in BMI z-score, -0.05 (SD = 0.68, CI = -0.23 to 0.13), as compared to children in the Comparison Sample, -0.21 (SD = 0.67, CI = -0.31 to -0.11). No statistically significant differences were found for decline in FEV₁ between children in the Clinical Trial Group and the Comparison Sample. The key implication of these findings is that intensive behavioral and nutritional intervention is effective and needs to be adapted so that it can be broadly disseminated into clinical practice.