Prediction of incident diabetes mellitus by baseline IGF1 levels.
OBJECTIVE
IGF1 is associated with metabolic parameters and involved in glucose metabolism. Low-IGF1 has been implicated in the etiology of glucose intolerance and subjects with pathological causes of either low- or high-IGF1 are at risk of diabetes. We hypothesized that both low- and high-IGF1 levels increase the risk of diabetes and aimed to assess the role of IGF1 in the risk of developing diabetes in a large prospective study.


METHODS
An analysis of two prospective cohort studies, the DETECT study and SHIP.


METHODS
We measured IGF1 levels in 7777 nondiabetic subjects and assessed incident diabetes mellitus during follow-up.


RESULTS
There were 464 cases of incident diabetes during 32 229 person-years (time of follow-up in the DETECT study and SHIP: 4.5 and 5 years respectively). There was no heterogeneity between both studies (P > 0.4). The hazard ratios (HRs) of incident diabetes in subjects with IGF1 levels below the 10th or above the 90th age- and sex-specific percentile, compared to subjects with intermediate IGF1 levels, were 1.44 (95% confidence interval (CI) 1.07-1.94) and 1.55 (95% CI 1.06-2.06) respectively, after multiple adjustment. After further adjustment for metabolic parameters, the HR for low-IGF1 became insignificant. Analysis of IGF1 quintiles revealed a U-shaped association of IGF1 with risk of diabetes. Results remained similar after exclusion of patients with onset of new diabetes within 1 year or with borderline glucose or HbA1c levels at baseline.


CONCLUSIONS
Subjects with low- or high-IGF1 level are at increased risk of developing diabetes.
Medizinische Klinik-Innenstadt, Ludwig-Maximilians University, Munich, Germany. harald.schneider@med.uni-muenchen.de
Harald Jörn
HJ
Schneider
Nele
N
Friedrich
Jens
J
Klotsche
Sabine
S
Schipf
Matthias
M
Nauck
Henry
H
Völzke
Caroline
C
Sievers
Lars
L
Pieper
Winfried
W
März
Hans-Ulrich
HU
Wittchen
Günter Karl
GK
Stalla
Henri
H
Wallaschofski
D000328:Adult; D000368:Aged; D001786:Blood Glucose; D016009:Chi-Square Distribution; D003920:Diabetes Mellitus / Q000097:blood* / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007334:Insulin-Like Growth Factor I; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors
D001786:Blood Glucose; D007334:Insulin-Like Growth Factor I