BODY-COMPOSITION ASSESSED BY BIOELECTRICAL-IMPEDANCE ANALYSIS (BIA) AND THE CORRELATION WITH PLASMA INSULIN-LIKE GROWTH-FACTOR-I (IGF-I) INNORMAL JAPANESE SUBJECTS AND PATIENTS WITH ACROMEGALY AND GH DEFICIENCY

Body composition was assessed by bioelectrical impedance analysis (BIA ) in 100 Japanese normal adults, 9 patients with acromegaly and 11 pat ients with growth hormone (GH) deficiency. Body weight (BW) was greate r in normal males than in normal females. Percent body fat (BF/BW) was greater in females than in males and was increased with age in both s exes. Percent total body water (TBW/BW) was less in females than in ma les. Although percent extracellular water (ECW/BW) was not different b etween both sexes, the ECW/TBW ratio was greater in females than in ma les. Percent body cell mass (BCM/BW) was lower in females than in male s. The patients with acromegaly had a lower percent BF but a higher pe rcent TBW, percent ECW and ECW/TBW ratio than normal subjects, while t he patients with GH deficiency had a higher percent BF and ECW/TBW rat io, but lower percent TBW. Percent body cell mass (BCM/BW) was higher in acromegaly and lower in GH deficiency than in normals. There was a negative correlation (r=-0.62) between plasma IGF-I levels and percent BF, whereas a positive correlation (r=0.51) was found between the pla sma IGF-I level and percent BCM. It is suggested, therefore, that body composition is affected by sex and age in normals, and by GH secretio n in patients with pituitary dysfunction. Plasma IGF-I levels may be o ne of the factors responsible for alterations in body composition.