DIMINISHED CONCENTRATIONS OF INSULIN-LIKE GROWTH-FACTOR-I IN CYSTIC-FIBROSIS

Cystic fibrosis is frequently accompanied by a catabolic condition wit h low body mass index caused by a number of disease complications. Ins ulin-like growth factor-I (IGF-I) is an anabolic hormone and an import ant marker of nutritional status, liver function, and linear growth. A vailable data on IGF-I in cystic fibrosis are sparse and conflicting. From 1990-3, 235 of our 240 patients (114 males, 121 females, median a ge 16.2 years, range 0.1-44.0 years) had IGF-I measured once by radioi mmunoassay. IGF-I was significantly reduced compared with a healthy Sc andinavian control population: mean (-2 SD to +2 SD) IGF-I SD score wa s -0.97 (-3.7 to 1.7) in males and -0.67 (-3.2 to 1.9) in females. Hei ght SD score was -0.95 (-3.3 to 1.4) in males and -0.81 (-3.2 to 1.6) in females. In patients who were stilt in the growth period a signific ant correlation of IGF-I SD score to height SD score (r=0.28, p<0.001) was found. The low IGF-I concentrations may reflect the catabolic sta te of many patients with cystic fibrosis and play a part in their abno rmal growth pattern.