Longitudinal relationship among growth, nutritional status, and pulmonary function in children with cystic fibrosis: Analysis of the Cystic Fibrosis Foundation National CF Patient Registry

TLDR

The study aimed to prospectively determine how growth, nutritional status, and pulmonary function interrelate over four years in children with cystic fibrosis. Using longitudinal data from 968 CF children aged 5–8 in the CF Foundation National CF Patient Registry (1991–1995), the authors modeled FEV₁% decline as a curvilinear function of baseline FEV₁% and covariates including age, sex, height and weight z‑scores, percent height‑appropriate body weight, and hospitalization days. Results showed that growth and nutrition are unstable in prepubertal CF children, with boys gaining height while girls lose height and weight z‑scores, and that weight‑related z‑scores are significantly associated with FEV₁% decline, suggesting that nutritional interventions may slow pulmonary deterioration.

Abstract

To determine prospectively the relationship among growth, nutritional status, and pulmonary function over a 4-year period in a large cohort of children with cystic fibrosis (CF).CF Foundation National CF Patient Registry data collected from 1991 to 1995 for 968 children (507 male) aged 5 to 8 years with pancreatic insufficiency and forced expiratory volume in 1 second within 60% to 140% of predicted values (FEV(1)%) were analyzed longitudinally. Variables hypothesized to affect FEV(1)% included age, sex, z scores for height, weight, percent of height-appropriate body weight, and annual number of days hospitalized.The significant decline in FEV(1)% was curvilinear and dependent on baseline FEV(1)%; children with initial FEV(1)% > or = 90 declined 2.6 U/y more than those with initial FEV(1)% <90. Boys gained but girls declined in z scores for height. Girls decreased in z scores for weight at a greater rate than boys. The z scores for weight and percent of height-appropriate body weight were significantly associated with longitudinal changes in FEV(1)%, after adjustment was done for hospitalizations.Growth, nutritional status, and pulmonary function are not stable in prepubertal children with CF and pancreatic insufficiency. Important sex-related differences in growth occur before puberty. Growth and nutritional status are associated with changes in FEV(1)%, suggesting that nutritional intervention may slow the decline in pulmonary function in children with CF.