EFFECT OF LINOLEIC-ACID INTAKE ON GROWTH OF INFANTS WITH CYSTIC-FIBROSIS

Essential fatty acid deficiency as a result of inadequate linoleic aci d impairs growth in healthy infants and is common in infants with mala bsorption due to cystic fibrosis (CF). We investigated the effect of d ietary linoleic acid intake on the growth of infants with CF. In this study, predigested formula preparations A and B, with linoleic acid co ntents of 12% and 7% of energy, respectively, were fed before and afte r 1989 to infants enrolled in the evaluation and treatment protocol of the Wisconsin CF Neonatal Screening Project. Outcome was assessed fro m height-for-age (HAZ) and weight-for-age (WAZ) Z scores on follow-up exams during the first year. Baseline characteristics did not differ s ignificantly between groups A (n = 43) and B (n = 33). At diagnosis, 5 3% of the enrolled infants (n = 76) showed low plasma linoleic acid co ncentrations and 22% had a high ratio of triene to tetraene. After cor recting for the effect of potentially confounding variables, we found that HAZ (by 0.27, P < 0.05) acid WAZ (by 0.26, P = 0.081) were higher in group A than in group B. This occurred despite a significantly hig her energy intake in group B. This difference was most pronounced betw een 6 and 9 mo of age. Our results suggest that a high linoleic acid c ontent in formula benefits infants with CF because it optimizes nutrit ion, growth, and feeding efficiency.