Metabolic syndrome and the risk of abdominal aortic aneurysm: A nationwide cohort study

Background and aims: The association between metabolic syndrome (MetS) and abdominal aortic aneurysm (AAA) remains unclear. We investigated the potential association between AAA and MetS and its components in a large population-based cohort. Methods: We used the Korean National Health Insurance Service database including 4,162,640 participants aged >= 50 years who received a routine health examination in 2009. Cox proportional hazards models were used to analyze the association between MetS and its components (elevated waist circumference, blood pressure, glucose, triglycerides, and reduced high-density lipoprotein cholesterol [HDL-C]) with AAA incidence, with adjustment for confounders. Results: During a median 9.4 years of follow-up, 18,160 participants developed incident AAA. MetS was associated with an increased risk of AAA compared to the non-MetS group (adjusted hazard ratio [aHR], 1.38; 95% confidence interval [CI], 1.34-1.43). Among the individual components, elevated waist circumference, blood pressure, triglycerides, and reduced HDL-C were associated with increased AAA risk, while elevated glucose alone was associated with reduced AAA risk (aHR, 0.85; 95% CI, 0.82-0.87). AAA risk also increased linearly with the increasing number of MetS components, with the highest risk found in the presence of all 5 components (aHR, 1.98, 95% CI, 1.83-2.15). Conclusions: MetS and its individual components, with the exclusion of elevated glucose, were associated with higher risk of AAA. Further studies are warranted to elucidate the association between MetS and AAA.