Background: Coronary artery disease (CAD) was the second leading cause of death for the past 3 years in Taiwan. The insulin-like growth factor (IGF) system is considered a new risk factor of CAD because investigations show that the levels and bioactivity of IGF-I and IGFBP-3 (where IGFBP is insulin-like growth factor-binding protein) may be involved in elevating the risk of CAD. This study investigated the relationships among IGF-I +1770, IGF-I +6093, and IGFBP-3 -202 genetic polymorphisms and CAD in the Taiwanese population.
Methods: A total of 581 subjects, including 390 non-CAD controls and 191 patients with CAD, were recruited and the isolated DNA was subjected to real-time polymerase chain to evaluate the effects of these three polymorphic variants on CAD.
Results: Our results showed a significant association between the IGF-I +1770 gene polymorphism and increased risk of CAD. Furthermore, CAD patients with a minimum of one mutant C allele, T/C or C/C, in IGF-I +1770 gene polymorphism had significantly high blood pressure including systolic blood pressure (SBP; P = 0.025) and diastolic blood pressure (DBP; P = 0.004), compared to CAD patients with T/T homozygotes. Moreover, CAD patients with a minimum of one mutant A allele, G/A or A/A, in the IGF-I +6093 gene polymorphism had a 1.695-fold elevated risk of congestive heart failure (CHF), compared to CAD patients with the G/G homozygote.
Conclusions: Polymorphism of IGF-I +1770 was associated with increased CAD risk. In CAD patients, the contributions of IGF-I +1770 and +6093 could be through the effect on blood pressure in CAD patients.
© 2013 Wiley Periodicals, Inc.