Significant Association between Serum Monokine Induced by Gamma Interferon and Carotid Intima Media Thickness

Abstract

Aim: The immune system may play an important role in the pathogenesis of cardiovascular disease. T cell-driven inflammation in human hypertension and atherosclerosis has recently been revealed. In the present study, we evaluated the association between serum levels of the C-X-C chemokine receptor type 3 chemokines and the carotid intima media thickness (IMT) in humans. Methods: One hundred sixty-four consecutive patients undergoing baseline and 2-year follow-up carotid IMT (110 men, 62.4 +/- 10.0 years) were enrolled. The maximum carotid IMT (max-IMT) and the mean carotid IMT (mean-IMT) were measured at baseline and after 24 months. Clinical and laboratory variables, including serum levels of the monokine induced by gamma interferon (MIG) and interferon gamma-induced protein 10 (IP-10), were analyzed at the time of initial enrollment. Results: The baseline max-and mean-IMT were 0.992 +/- 0.235 and 0.793 +/- 0.191 mm, respectively. The serum levels of MIG and IP-10 significantly correlated with the carotid IMT. However, there was no significant correlation between the serum levels of MIG or IP-10 and IMT changes. A multi-variate regression analysis revealed the serum MIG to be independently associated with the carotid IMT (max-IMT: beta=0.194, p=0.010; mean-IMT: beta=0.184, p=0.016) when controlled for age, sex, diabetes mellitus history, smoking history, body mass index, blood pressure, total cholesterol, high-density lipoprotein cholesterol, high-sensitivity C-reactive protein, and aspirin and statin medication. Conclusions: Circulating MIG levels are independently associated with the carotid IMT, after adjusting for confounding factors and medications. These findings indicate the potential clinical implication of MIG with respect to early atherosclerosis in humans.