The lack of effective pharmacotherapies for aortic aneurysms (AA) is a persistent clinical challenge. Lipid metabolism plays an essential role in AA. However, the impact of lipid-lowering drugs on AA remains controversial. The study aimed to investigate the genetic association between lipid-lowering drugs and AA.

Our research used publicly available data on genome-wide association studies (GWASs) and expression quantitative trait loci (eQTL) studies. Genetic instruments, specifically eQTLs related to drug-target genes and SNPs (single nucleotide polymorphisms) located near or within the drug-target loci associated with low-density lipoprotein cholesterol (LDL-C), have been served as proxies for lipid-lowering medications. Drug-Target Mendelian Randomization (MR) study is used to determine the causal association between lipid-lowering drugs and different types of AA. The MR analysis revealed that higher expression of HMGCR (3-hydroxy-3-methylglutaryl coenzyme A reductase) was associated with increased risk of AA (OR = 1.58, 95% CI = 1.20–2.09, P = 1.20 × 10⁻⁰³) and larger lumen size (aortic maximum area: OR = 1.28, 95% CI = 1.13–1.46, P = 1.48 × 10⁻⁰⁴; aortic minimum area: OR = 1.26, 95% CI = 1.21–1.42, P = 1.78 × 10⁻⁰⁴). PCSK9 (proprotein convertase subtilisin/kexin type 9) and CETP (cholesteryl ester transfer protein) show a suggestive relationship with AA (PCSK9: OR = 1.34, 95% CI = 1.10–1.63, P = 3.07 × 10⁻⁰³; CETP: OR = 1.38, 95% CI = 1.06–1.80, P = 1.47 × 10⁻⁰²). No evidence to support genetically mediated NPC1L1 (Niemann–Pick C1-Like 1) and LDLR (low-density lipoprotein cholesterol receptor) are associated with AA.

This study provides causal evidence for the genetic association between lipid-lowering drugs and AA. Higher gene expression of HMGCR, PCSK9, and CETP increases AA risk. Furthermore, HMGCR inhibitors may link with smaller aortic lumen size.

This Mendelian randomization study used publicly available data involving over 1 million individuals to demonstrate the causal relationship between five target genes of LDL-C-lowering medicines and the risk of aortic aneurysms, and implied one lipid-lowering drug may link with the lumen size of aortic aneurysms.