The association between lipid parameters and erectile dysfunction: a two-sample Mendelian randomization and...

Lipid parameters have been shown to have significant predictive value for cardiovascular disease, but few studies have evaluated their correlation with erectile dysfunction (ED) in young men.

The case-control study encompassed 186 young ED patients (ages 20-40) and 186 healthy controls. Lipid parameters, including total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), TC/HDL ratio, TG/HDL ratio, and LDL-C/HDL-C ratio, were assessed in all participants. The International Index of Erectile Function (IIEF-5) scores were collected for all participants to evaluate erectile status. Multivariate logistic regression analysis was utilized to appraise the association of lipid-related parameters with ED. Single-nucleotide polymorphisms (SNPs) significantly correlated with lipid parameters (TC, TG, LDL-C, HDL-C) were selected from genome-wide association studies (GWAS) as instrumental variables (IV) (P < 5.0 × 10^-8). Summary data for ED was gathered from a GWAS with a sample size of (n = 17,353 cases/28,210 controls). The inverse variance weighted (IVW) method was employed as the primary mendelian randomization (MR) analysis method to assess causal effects. Causal estimates were represented as odds ratios (OR) with 95% confidence intervals (CI).

Results from the case-control study revealed that, when compared with the control group, levels of LDL-C, TG, UA, LDL-C/HDL-C, TG/HDL-C, and TC/HDL-C in the ED group were significantly elevated (P < 0.01), while HDL-C was significantly decreased (P < 0.01) in the ED group. Multivariate logistic regression analysis indicated LDL-C/HDL-C as a risk factor for both the incidence and severity of ED (P < 0.001). Two-sample MR analysis demonstrated no significant causal correlation between lipid parameters-LDL-C (OR, 0.98, 95% CI, 0.88-1.08, P = 0.616), HDL-C (OR, 1.07, 95% CI: 0.96-1.19, P = 0.249), TC (OR, 1.07, 95% CI, 0.96-1.18, P = 0.208), TG (OR, 0.98, 95% CI, 0.80-1.13, P = 0.579) -and an increased risk of ED (all P > 0.05).

The case-control analysis ascertained a significant association between LDL-C, HDL-C, LDL-C/HDL-C, and ED and its severity. However, results from the MR study do not support a causal role of lipid parameters in ED.