Insulin-like growth factor (IGF) I, -II, and IGF binding protein-3 and risk of ischemic stroke.
BACKGROUND
Low IGF-I levels may be associated with the development of stroke; however, prospective data appear to be unavailable.


METHODS
This was a nested case-control study within a Danish follow-up study, including 57,053 men and women. Baseline data included circulating IGF-I, IGF-II, and IGF binding protein (IGFBP)-3 concentrations as well as lifestyle factors and medical history. We identified 254 cases with incident ischemic stroke and 254 gender- and age-matched controls.


RESULTS
Participants in the bottom quartiles of IGF-I and IGFBP-3 levels (median concentrations, 72 and 2937 ng/ml, respectively) were at increased risk of ischemic stroke, e.g. adjusted odds ratios (ORs) of 2.06 [95% confidence interval (CI), 1.05-4.03] and 2.29 (95% CI, 1.17-4.49), respectively, when compared with participants in the top quartiles (median concentrations, 125 and 4835 ng/ml, respectively). A negative, although weaker, association was also found for IGF-II (adjusted OR 1.44, 95% CI 0.79-2.64) when comparing the bottom quartile with the top quartile. No substantial associations were seen for IGF-I and IGF-II when also adjusting for IGFBP-3; adjusting IGFBP-3 for IGF-I and -II had only a minor impact on the risk estimates.


CONCLUSIONS
These findings give some support to the hypothesis that the IGF axis is involved in the pathogenesis of ischemic stroke.
Johnsen
S P
SP
Department of Clinical Epidemiology, Aarhus University Hospital, Ole Worms Allé 150, DK-8000 Aarhus C, Denmark. spj@dce.au.dk
Hundborg
H H
HH
Sørensen
H T
HT
Orskov
H
H
Tjønneland
A
A
Overvad
K
K
Jørgensen
J O L
JO
D002545:Brain Ischemia / Q000097:blood / Q000209:etiology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D007335:Insulin-Like Growth Factor II / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D020521:Stroke / Q000097:blood / Q000209:etiology*
D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II