IGF-I gene promoter polymorphism is a predictor of survival after myocardial infarction in patients with type 2 diabetes.
OBJECTIVE
Previously we observed that non-carriers of the most common alleles of an IGF-I promoter polymorphism have low circulating IGF-I levels and an increased risk of developing myocardial infarction (MI), particularly in patients with type 2 diabetes.


METHODS
We investigated whether this IGF-I promoter polymorphism is associated with survival of type 2 diabetes in a Caucasian population aged 55 years and older.


METHODS
The study was embedded in the Rotterdam Study, a prospective population-based cohort study. At baseline, 668 patients with type 2 diabetes were diagnosed, among which, 55 incident MI were ascertained during follow-up. For the present study, we used two genotype groups: non-variant carriers (homozygous for 192, 194, or 192/194 bp genotypes), and variant carriers.


RESULTS
During a median follow-up of 8.8 years, 396 out of the 668 patients with type 2 diabetes (59.3%) died of various causes. The frequency of type 2 diabetes variant carrier and non-variant carriers was 28.7 and 71.3% respectively. The survival in patients with type 2 diabetes without an MI did not differ between the IGF-I genotype groups (hazard ratio (HR) = 0.8, 95% confidence interval (CI): 0.7-1.1, P = 0.1). In contrast, in those who developed an MI, variant carriers had a 2.4 times higher risk of mortality than non-variant carriers (95% CI: 1.2-4.8, P = 0.01).


CONCLUSIONS
Our study suggests that genetically determined low IGF-I activity is an important determinant of survival in patients with type 2 diabetes who developed an MI. The IGF-I promoter polymorphism, therefore, may help to predict the future mortality risk in this group of patients.
Yazdanpanah
Mojgan
M
Department of Epidemiology and Biostatistics, Erasmus Medical Centre, PO Box 2040, 3000 CA Rotterdam, The Netherlands.
Sayed-Tabatabaei
Fakhredin A
FA
Janssen
Joop A M J L
JA
Rietveld
Ingrid
I
Hofman
Albert
A
Stijnen
Theo
T
Pols
Huibert A P
HA
Lamberts
Steven W J
SW
Witteman
Jacqueline C M
JC
van Duijn
Cornelia M
CM
D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics* / Q000401:mortality; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000235:genetics* / Q000401:mortality; D009426:Netherlands / Q000453:epidemiology; D011110:Polymorphism, Genetic / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011446:Prospective Studies; D016019:Survival Analysis
D007334:Insulin-Like Growth Factor I