IGF‐I concentrations are positively associated with carotid artery atherosclerosis in women

Abstract

BACKGROUND. Alterations in the growth hormone (GH)/insulin‐like growth factor I (IGF‐I) axis are associated with increased cardiovascular morbidity and mortality, but previous studies have yielded conflicting results. In addition, the T1169A polymorphism in the GH1 gene has been associated with IGF‐I levels.

AIMS. To investigate whether IGF‐I concentrations and the T1169A polymorphism of the GH1 gene are associated with cardiovascular risk factors and the intima media thickness (IMT) of the carotid artery.

METHODS. Fasting plasma IGF‐I concentrations (n = 1008) were measured in a large population‐based OPERA (Oulu Project Elucidating Risk of Atherosclerosis) cohort. Genotype variants were determined by the restriction fragment length polymorphism method.

RESULTS. Low IGF‐I concentrations associated with several cardiovascular risk factors including age, adiposity, and high triglyceride, fasting insulin and C‐reactive protein concentrations in the analysis of all subjects. In the multivariate models, however, IGF‐I concentrations were positively associated with the mean IMT of women (ß = 0.127, P = 0.009) whereas the association in men was weaker and negative (ß = −0.088, P = 0.034). The 1169A allele was associated with low low‐density lipoprotein cholesterol in both sexes and with low systolic blood pressure levels in women.

CONCLUSIONS. IGF‐I concentrations were associated with several traditional cardiovascular risk factors. The observed gender difference in the association between IGF‐I concentrations and carotid artery atherosclerosis warrants further study. The GH1 1169A allele may be associated with a favourable metabolic profile.

• Cardiovascular disease
• intima‐media thickness
• insulin‐like growth factor I

Acknowledgements

The authors thank Ms Heidi Häikiö, Ms Helena Kalliokoski, Ms Saija Kortetjärvi and Ms Riitta Vanhanen for skilful technical assistance. This study was supported by the Medical Council of the Academy of Finland and the Finnish Foundation for Cardiovascular Research.