C-peptide, IGF-I, sex-steroid hormones and adiposity: a cross-sectional study in healthy women within the European Prospective Investigation into Cancer and Nutrition (EPIC).
OBJECTIVE
The risk of some cancers is positively associated with body weight, which may influence circulating levels of sex-steroid hormones, insulin and IGF-I. Interrelationships between these hormones and the associations with adiposity were evaluated in healthy women participating in the European Prospective Investigation into Cancer and Nutrition (EPIC).


METHODS
A cross-sectional analysis was performed on anthropometric and hormonal data from 743 pre- and 1217 postmenopausal women. Body mass index (BMI) and waist circumference were used as indicators of adiposity. C-peptide, Insulin Growth Factor (IGF)-I, Insulin Growth Factor binding protein (IGFBP)-3, androgens, estrogens and sex hormone binding globulin (SHBG) were measured by immunoassays; free sex steroid concentrations were calculated.


RESULTS
BMI and waist circumference were positively correlated with estrogens in postmenopausal women and with C-peptide, free testosterone and inversely with SHBG in all women. C-peptide and IGF-I were inversely correlated with SHBG, and positively with free sex steroids in postmenopausal women. IGF-I was positively associated with postmenopausal estrogens and androgen concentrations in all women.


CONCLUSIONS
Sex-steroid concentrations appear to be regulated along several axes. Adiposity correlated directly with estrogens in postmenopausal women and with insulin, resulting in lower SHBG and increased levels of free sex steroids. Independent of adiposity and insulin, IGF-I was associated with decreased SHBG levels, and increased concentrations of androgens and postmenopausal estrogens.
Bezemer
Irene D
ID
International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372, Lyon CEDEX 08, France.
Rinaldi
Sabina
S
Dossus
Laure
L
Gils
Carla H van
CH
Peeters
Petra H M
PH
Noord
Paulus A H van
PA
Bueno-de-Mesquita
H Bas
HB
Johnsen
Soren Paaske
SP
Overvad
Kim
K
Olsen
Anja
A
Tjønneland
Anne
A
Boeing
Heiner
H
Lahmann
Petra H
PH
Linseisen
Jakob
J
Nagel
Gabriele
G
Allen
Naomi
N
Roddam
Andrew
A
Bingham
Sheila
S
Khaw
Kay-Tee
KT
Kesse
Emmanuelle
E
Téhard
Bertrand
B
Clavel-Chapelon
Françoise
F
Agudo
Antonio
A
Ardanaz
Eva
E
Quiros
J R
JR
Amiano
Pilar
P
Martínez-Garcia
C
C
Tormo
M J
MJ
Pala
Valeria
V
Panico
Salvatore
S
Vineis
Paolo
P
Palli
Domenico
D
Tumino
Rosario
R
Trichopoulou
Antonia
A
Baibas
N
N
Zilis
D
D
Hémon
Bertrand
B
Norat
Teresa
T
Riboli
Elio
E
Kaaks
Rudolf
R
D000728:Androgens / Q000097:blood; D015992:Body Mass Index; D002096:C-Peptide / Q000097:blood*; D003430:Cross-Sectional Studies; D004967:Estrogens / Q000097:blood; D005260:Female; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008875:Middle Aged; D017698:Postmenopause; D017697:Premenopause; D011446:Prospective Studies; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D049629:Waist-Hip Ratio
D000728:Androgens; D002096:C-Peptide; D004967:Estrogens; D018972:Insulin-Like Growth Factor Binding Protein 3; D012738:Sex Hormone-Binding Globulin; D007334:Insulin-Like Growth Factor I