Serum IGF-I levels are similar in Samoan, Māori and European populations despite differences in body composition.
OBJECTIVE
To determine if serum IGF-I concentrations are similar in healthy adult subjects from the Samoan, Māori and European populations in New Zealand.


METHODS
Serum IGF-I concentration was measured in 75 healthy adults, aged 18-50 years, of Samoan (n=23), Māori (n=22) and European (n=30) descent. Body composition was assessed using standard anthropomorphic measures. In addition all subjects had body composition assessed by Dual energy X-ray absorptiometry (DXA).


RESULTS
Weight, body mass index (BMI), and fat mass were significantly greater in Māori and Samoan subjects than European subjects (ANOVA p=0.006, p=0.0003, p=0.03, respectively). However, serum IGF-I concentration was similar between the groups (European 186.8 SEM 14.9 microg/l, Māori 204.8 SEM 17.1 microg/l, Samoan 180.0 SEM 17.5 microg/l, p=0.58). IGF-I levels were similar between ethnic groups after adjustment (ANCOVA) for age, sex or BMI (p=0.5) or age, sex and fat mass (p=0.44). In multivariate analysis the only independent predictor of IGF-I was age (p<0.001) and explained 22% of the variance in IGF-I level.


CONCLUSIONS
Serum IGF-I concentrations were similar in Māori, Samoan and European population groups in New Zealand, despite significant differences in anthropomorphic variables and body composition.
Bagg
W
W
Department of Medicine, University of Auckland, E-com House, 3 Ferncroft Street, Grafton, Auckland, New Zealand. w.bagg@auckland.ac.nz
Aoina
J
J
Cross
P A R
PA
Whalley
G A
GA
Gamble
G D
GD
Doughty
R N
RN
Holdaway
I M
IM
D000328:Adult; D001823:Body Composition; D015992:Body Mass Index; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D009520:New Zealand; D044465:White People / Q000208:ethnology
D007334:Insulin-Like Growth Factor I