Metabolic Syndrome, Diabetes, and Incidence and Progression of Coronary Calcium : The Multiethnic Study of Atherosclerosis Study

ObjectivesThis study sought to examine and compare the incidence and progression of coronary artery calcium (CAC) among persons with metabolic syndrome (MetS) and diabetes mellitus (DM) versus those with neither condition.BackgroundMetS and DM are associated with subclinical atherosclerosis as evidenced by CAC.MethodsThe MESA (Multiethnic Study of Atherosclerosis) included 6,814 African American, Asian, Caucasian, and Hispanic adults 45 to 84 years of age, who were free of cardiovascular disease at baseline. Of these, 5,662 subjects (51% women, mean age 61.0 ± 10.3 years) received baseline and follow-up (mean 2.4 years) cardiac computed tomography scans. We compared the incidence of CAC in 2,927 subjects without CAC at baseline and progression of CAC in 2,735 subjects with CAC at baseline in those with MetS without DM (25.2%), DM without MetS (3.5%), or both DM and MetS (9.0%) to incidence and progression in subjects with neither MetS nor DM (58%). Progression of CAC was also examined in relation to coronary heart disease events over an additional 4.9 years.ResultsRelative to those with neither MetS nor DM, adjusted relative risks (95% confidence intervals [CI]) for incident CAC were 1.7 (95% CI: 1.4 to 2.0), 1.9 (95% CI: 1.4 to 2.4), and 1.8 (95% CI: 1.4 to 2.2) (all p < 0.01), and absolute differences in mean progression (volume score) were 7.8 (95% CI: 4.0 to 11.6; p < 0.01), 11.6 (95% CI: 2.7 to 20.5; p < 0.05), and 22.6 (95% CI: 17.2 to 27.9; p < 0.01) for those with MetS without DM, DM without MetS, and both DM and MetS, respectively. Similar findings were seen in analysis using Agatston calcium score. In addition, progression predicted coronary heart disease events in those with MetS without DM (adjusted hazard ratio: 4.1, 95% CI: 2.0 to 8.5, p < 0.01) and DM (adjusted hazard ratio: 4.9 [95% CI: 1.3 to 18.4], p < 0.05) among those in the highest tertile of CAC increase versus no increase.ConclusionsIndividuals with MetS and DM have a greater incidence and absolute progression of CAC compared with individuals without these conditions, with progression also predicting coronary heart disease events in those with MetS and DM.