Abstract
Circulating lipids are potentially modifiable risk factors for aortic aneurysm, however, associations between levels of specific lipids and aortic aneurysm are unclear. We analysed associations between blood lipids and aortic aneurysm in the UK Biobank and summarized the available data in a systematic review and meta-analysis of published cohort studies. Up to 429,610 participants aged 38-73 years at baseline in 2006-2010 in UK Biobank were included. Multivariable Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between serum/plasma lipids (total cholesterol, low-density lipoprotein [LDL] cholesterol, high-density lipoprotein [HDL] cholesterol, triglycerides, apolipoprotein A1, apolipoprotein B, and lipoprotein(a)) and risk of aortic aneurysm. PubMed and Embase databases were searched up to November 11th, 2025, to identify relevant cohort studies. Random-effects models were used to estimate summary relative risks (RRs) and 95% CIs for the associations between blood lipid levels and aortic aneurysm risk. In UK Biobank, 2,434 aortic aneurysm cases occurred during 12.3 years of follow-up. Positive associations were observed between the highest vs. lowest quintile of total cholesterol (HR 1.22, 95% CI 1.07-1.41), LDL cholesterol (1.39, 1.21-1.60), apolipoprotein B (1.52, 1.33-1.74), non-HDL cholesterol (1.50, 1.29-1.73), triglycerides (1.23, 1.06-1.42), lipoprotein(a) (1.34, 1.17-1.54) and aortic aneurysm risk, while HDL cholesterol (0.57, 0.48-0.67) and apolipoprotein A1 (0.54, 0.46-0.63) were inversely associated. Eighteen cohort studies were included in the meta-analysis. The summary RR (95% CI) per 1 mmol/L increase was 1.16 (1.10-1.22, I2 = 74%, n = 15) for total cholesterol, 1.11 (1.04-1.19,I2 = 63%, n = 4) for LDL cholesterol, 1.28 (0.98-1.67, I2 = 89%, n = 2) for non-HDL cholesterol, 0.59 (0.50-0.70, I2 = 72%, n = 5) for HDL cholesterol, 1.02 (0.95-1.10, I2 = 55%, n = 7) for triglycerides, and 1.34 (1.17-1.55, I2 = 57%, n = 4) per 50 mg/dl incrememt in lipoprotein(a). Additional positive (apolipoprotein B, non-HDL cholesterol) and inverse (apolipoprotein A1) associations were observed in high vs. low meta-analyses. These findings suggest higher levels of total cholesterol, LDL cholesterol, apolipoprotein B, non-HDL cholesterol, lipoprotein(a), and possibly triglycerides are associated with increased risk of aortic aneurysm, while higher levels of HDL cholesterol and apolipoprotein A1 are associated with lower risk.</p>