[Causal relationship between insomnia and erectile dysfunction based on heart-kidney intersection theory: A two-sample Mendelian randomization study].

Objective: Previous studies have shown that insomnia is closely related to erectile dysfunction（ED）. However, the causal relationship between them is still unclear. Mendelian randomization (MR) provides a new method for studying the relationship between the two, and the theory of heart-kidney interaction in TCM provides a new idea for exploring the causal relationship between them.

Methods: Based on the statistical data collected by genome-wide association studies (GWAS), the causal relationship between insomnia and ED was discussed by MR. Inverse variance weighted (IVW) is the main analysis method, and weighted median (WME), simple mode (SM), weighted mode (WM) and MR Egger method were the supplementary analysis to evaluate the causal effect. MR-Egger intercept test, Cochran Q test and leave-one-out method were used in sensitivity analysis to verify the reliability of MR results.

Results: Thirty-nine SNPs significantly related to insomnia were finally included for MR analysis. The results of IVW method in MR analysis showed that insomnia had a significant causal relationship with the increased risk of ED (OR = 3.111，95% CI= 1.566－6.181，P=1.193×10－3). The results obtained by MR-Egger method, WME method, WM method and SM method were consistent with IVW method in the direction of effect. The sensitivity results suggested that the results of this study were robust.

Conclusion: Our study reveals the causal relationship between insomnia and ED, which provides a new basis for future clinical practice and prevention and treatment of ED.