Associations between Metabolic Syndrome Indicators and Colon Polyps: A Mendelian Randomization Study

Background While observational studies have suggested a potential link between metabolic syndrome (MetS) and an increased risk of colon polyps, the causal nature of this association remains uncertain. This study used a two-sample Mendelian randomization (MR) approach to evaluate the relationship between MetS and colon polyps.

Methods A two-sample MR analysis was performed using data on MetS, its indicators, and colon polyps obtained from publicly available genome-wide association studies in the Integrative Epidemiology Unit (IEU) and MAGIC databases. Outliers were removed using Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO), followed by MR calculations and false discovery rate (FDR) correction. The primary analysis was conducted with the inverse variance-weighted (IVW) method.

Results The IVW results indicated no association between hypertension, hyperlipidemia, or diabetes and the risk of colon polyps. High-density lipoprotein cholesterol (HDL-C) (P=0.005), 2-hour glucose (P=0.004), glycated hemoglobin A1c (P=0.004), and the ratio of omega-6 to omega-3 fatty acids (P<0.001) were negatively associated with colon polyps. Conversely, body mass index (BMI) (P<0.001), body fat percentage (P=0.002), waist-to-hip ratio adjusted for BMI (P=0.001), total cholesterol (TC) (P=0.002), triglycerides (TG) (P<0.001), and both omega-3 (P<0.001) and omega-6 fatty acid levels (P=0.02) were positively associated with colon polyps. The relationships between these metabolic indicators and colon polyps remained significant after FDR correction.

Conclusion Obesity-related traits, TC, and TG may increase the risk of colon polyps, while HDL-C may have a protective effect.