Relationship between clinical parameters and linear growth in children with cystic fibrosis.

Mixed longitudinal height data from 1,170 cystic fibrosis patients seen at Rainbow Babies and Childrens Hospital in Cleveland form the basis for this analysis. As a group, the patients experience growth retardation throughout the growth cycle, with median height values below the 25th percentile of NCHS standards until late adolescence. Median height increments are also below normal standards until age 16 years in boys and 14 years in girls. Based on these results, it appears that some CF patients have very delayed adolescent growth spurts, and continue to grow into early adulthood. Pancreataic-enzyme-sufficient patients have greater height-for-age percentiles than enzyme-deficient patients after 9 years of age. The overall difference between enzyme-sufficient and enzyme-deficient patients is not statistically significant (P=0.058), perhaps because of small sample size for the enzyme-sufficient group (n=19). The correlation between pulmonary status assessed from lung X-rays and height increment peaks at age 10 years in girls and age 15 years in boys, with significant negative correlation occurring after age 16 years in both sexes. Although both pancreatic enzyme deficiency and lung disease appear to have some effect on linear growth in CF, especially during adolescence, these two factors explain a relatively small portion of the variation in growth percentiles.