The association of metabolic syndrome with aortic aneurysm: a two-sample Mendelian randomization study

Metabolic syndrome (MetS) has been proved to be associated with cardiovascular disease, and recent observational studies have revealed the association between MetS and its components and aortic aneurysm (AA), but the causal relationship still uncertain. The study aimed to explore the causal effect of MetS on AA using Mendelian randomization (MR) analysis.

Single nucleotide polymorphisms (SNP) of MetS and its components were extracted from publicly available genome-wide association study (GWAS) database. Inverse variance weighting (IVW), weighted median method, simple mode method, weighted mode method, and MR-Egger regression were used to evaluate causality. Sensitivity analysis, heterogeneity test, and pleiotropy test were done so as to ensure the stability of the analyzed results.

IVW showed that genetically predicted MetS had a significantly positive association with the risk of AA (OR: 1.308; 95% CI 1.175-1.456). In exploring the causal relationship between the components of MetS and AA, body mass index (BMI) (OR: 1.322; 95% CI 1.132-1.543), waist circumstance (WC) (OR: 1.282; 95% CI 1.055-1.558), triglycerides (TG) (OR: 1.436; 95% CI 1.253-1.646), systolic blood pressure (SBP) (OR: 1.023; 95% CI 1.014-1.033), and diastolic blood pressure (DBP) (OR: 1.086; 95% CI 1.069-1.103) could increase the risk of AA. However, high density lipoprotein cholesterol (HDL-C) (OR: 0.722; 95% CI 0.638-0.818), fasting blood glucose (OR: 0.683; 95% CI 0.488-0.957) and type 2 diabetes (T2DM) (OR: 0.904; 95% CI 0.831-0.983) were negative association with the risk of AA.

The present study strengthened the evidence for a causal association between MetS and the risk of AA and revealed that MetS and its individual components, excluding elevated blood glucose and T2DM, increased the risk of AA.