Aging and metabolic syndrome effect on carotid atherosclerosis assessed by ultrasonography

Objective:  To investigate the relationships between carotid atherosclerosis, age and metabolic syndrome (MetS), by ultrasonographically examining the carotid arteries of subjects who ranged from young adults to centenarians.

Methods:  Carotid intima-media thickness (IMT) was evaluated by B-mode ultrasonography in 1540 patients (685 men, aged 70 ± 15 years, and 855 women, aged 74 ± 13 years) in the Medical Department of Seiyo Municipal Nomura Hospital. We investigated the association between carotid IMT as well as plaque, and confounding risk factors including MetS by using the 2005 Japanese criteria.

Results:  MetS increased with age until the fifth to seventh decade of life but began to decrease in the more elderly subjects. Carotid IMT increased in a linear manner with age (r = 0.442, P < 0.001) and occurrence of plaques also increased up to the ninth decade of life (P for trend <0.001). Multiple logistic regression analysis for carotid IMT ≥1.10 mm and plaque occurrence was performed using age, sex, smoking status, low-density lipoprotein cholesterol and MetS as variables. In subjects less than 80 years old, male sex and MetS were significant factors for carotid IMT ≥1.10 mm. However, in subjects 80 years or older, MetS was not related to carotid IMT ≥1.10 mm. The appearance of plaque was associated with age and smoking status, but not with MetS.

Conclusion:  MetS confers an increased risk of cardiovascular morbidity in subjects aged less than 80 years, and its identification may thus be important in risk assessment and treatment of patients.