Carotid Intima-Media Thickness and Brachial Artery Flow-Mediated Dilatation in Patients with and without Metabolic Syndrome.

ABSTRACT

BACKGROUND, Metabolic syndrome has recently emerged as a marker of future cardiovascular risk. However its incremental value for this purpose, over conventional cardiovascular risk factors and diabetes mellitus in particular, is debated. The present study was conducted to determine the extent of subclinical atherosclerosis in patients with metabolic syndrome, and compare it with the same in individuals with cardiovascular risk factors not having metabolic syndrome. METHODS, A total of 156 individuals seeking outpatient cardiac consultation for various indications were included in the study and were divided into four groups - group 1 cardiovascular risk factors present but not metabolic syndrome (n = 60) group 2 metabolic syndrome without diabetes mellitus or coronary artery disease (n = 21) ;group 3 metabolic syndrome with diabetes mellitus without coronary artery disease ( n = 27) ;and group 4patients with documented coronary artery disease (n = 48). Metabolic syndrome was diagnosed on the basis of Adult Treatment Panel III (ATPIII) criteria. All patients underwent assessment of carotid intima-media thickness and brachial artery flow-mediated vasodilatation. RESULTS, Both carotid intima-media thickness and brachial artery flow-mediated vasodilatation were similar in groups 1 and 2 (carotid intima-media thickness 0.687 -/+ 0.13mm and 0.706 -/+0.23mm, p = 0.963; brachial artery flow-mediated vasodilatation 11.80 -/+ 5.16% and 12.87 -/+ 7.04%, respectively, p =0.883) , but group 3 patients had significantly higher carotid intima-media thickness (0.774 +/- 0.15mm, p = 0.047) and significantly lower brachial artery flow-mediated vasodilatation (7.37 -/+ 6.12%, p -/+ 0.007) as compared to group 1 patients. There was no significant difference in the two parameters between groups 3 and 4 (carotid intima-media thickness in group 40.789 -/+ 0.16mm,p = 0.976 and brachial artery flow-mediated vasodilatation5.86 -/+ 3.85%, p -/+ 0.709). CONCLUSIONS, In absence of diabetes mellitus, metabolic syndrome was not associated with greater extent of subclinical atherosclerosis compared to individual cardiovascular risk factors. Presence of diabetes mellitus, however, resulted in significant endothelial dysfunction and evidence of subclinical atherosclerosis, similar to that seen in patients with already established coronary artery disease.