Metabolic Syndrome and Early Carotid Atherosclerosis in the Elderly

Aims: To investigate whether metabolic syndrome(MetS) can predict the new onset of carotid plaque or the progression of carotid intima-media thickness(C-IMT) and identify other associated factors in an elderly population without evidence of early carotid atherosclerosis. Methods: B-mode carotid ultrasonography was used to assess the presence of carotid plaque and the C-IMT at baseline and follow-up. Participants with carotid plaque or an increased C-IMT(≥1.0mm) at baseline were excluded from the study. The new occurrence of carotid plaque, defined as early carotid atherosclerosis and the progression of C-IMT, was evaluated. Multiple regression analyses were used to determine predictors of these findings. Results: A total of 370participants over 60years of age(median age=66years, 34.1% men) were enrolled. After a median follow-up period of 25 months, 64participants(17.3%) had newly developed carotid plaque. After adjusting for variables determined to be statistically significant in univariate analyses, a multivariable regression analysis showed that predictors of newly developed carotid plaque were metabolic syndrome(hazard ratio [HR]=1.916; 95% confidence interval [CI]: 1.059-3.466), white blood cell count(HR=1.313; 95% CI: 1.094-1.576) and vitamin B12(HR=1.001; 95% CI: 1.000-1.002) and total cholesterol(HR=1.009; 95% CI: 1.001-1.017) levels. A multiple linear regression analysis showed that the rate of change for C-IMT tended to be associated with the development of metabolic syndrome. Conclusions: Metabolic syndrome is associated with the progression of early carotid atherosclerosis in the general population, suggesting that metabolic syndrome plays an important role in initiating the atherosclerotic process.