Impact of metabolic syndrome and its components on the progression of coronary artery calcification in statin-naive young adults: results from the KOICA registry

Abstract Background Metabolic syndrome (MetS) is known to be associated with the progression of coronary artery calcification (CAC). However, the relative risks of CAC progression according to the presence of MetS and individual components of MetS in young adults are unknown. Purpose We investigated the impact of MetS, the number of meeting MetS components (metabolic burden), and each component of MetS on CAC progression in statin-naïve young adults. Also, we evaluated the association between the change of metabolic burden and CAC progression. Methods From the KOrea Initiatives on Coronary Artery calcification (KOICA) registry, we included 2,151 asymptomatic adults aged between 20 and 45 years who underwent serial coronary artery calcium scans as a part of health examination. The difference of ≥2.5 between the square roots of coronary artery calcium score at the baseline and follow-up measured by Agatston units was defined as CAC progression. We estimated the risk of CAC progression according to the presence of MetS, individual components of MetS, and metabolic burden using Cox proportional-hazards models. Among young adults with MetS, the impact of the metabolic burden decrement on CAC progression was evaluated by a logistic regression model. Results Of 2,151 young adults (mean age 41.3±3.8 years, male 85.4%), 488 (22.7%) adults had MetS at baseline health examination. During a median follow-up of 2.1 years, CAC progression was observed in 325 (15.1%) adults. MetS was significantly associated with an increased risk of CAC progression after adjusting for other cardiovascular risk factors: adjusted hazard ratio (aHR) 2.59, 95% confidence interval (CI): 1.97–3.42, p<0.001. There was a positive linear correlation between metabolic burden and the risk of CAC progression with an approximately 7-fold higher risk in the group having metabolic burden of 4–5 (aHR 7.22, 95% CI: 4.10–12.72, p<0.001) than in the group without. Among each component of MetS, elevated blood pressure (BP), impaired fasting glucose (IFG), and elevated triglycerides (TG) were associated with the risk of CAC progression, demonstrating the strongest contribution of elevated BP (aHR 2.67, 95% CI: 2.00–3.56, p<0.001). Of note, a decrease of more than one metabolic burden in the follow-up examination was associated with the reduced risk of CAC progression in MetS adults than the others: odds ratio (95% CI), 0.46 (0.22–0.98), p=0.044. Conclusions In statin-naïve young adults, the metabolic burden is associated with CAC progression in a dose-response relationship. Elevated BP, TG, and IFG are metabolic derangements requiring special attention to care, and an improvement in metabolic imbalance might have a preventive effect on CAC progression. Funding Acknowledgement Type of funding sources: None.