Mendelian Randomization Sensitivity Analyses

In the analyzed study, we conducted an inverse-variance weighted (IVW) meta-analysis as the primary analysis method, employing a random-effects model (18 (link)). Additionally, we performed two sensitivity analyses using different methods. The first sensitivity analysis involved the weighted median method, which provides valid estimates if at least 50% of the information came from valid instrumental variables (19 (link), 20 (link)). The second sensitivity analysis employed the MR-Egger method to evaluate the presence of horizontal pleiotropy in the selected instrumental variables (21 (link), 22 (link)). To assess heterogeneity among the instrumental variables, we used Cochran's Q-value. Furthermore, we performed a leave-one-out sensitivity analysis to examine the potential impact of individual single nucleotide polymorphisms. The analytical procedures were carried out using R (version 4.3.1) and R Studio (version 2022.06.1 + 524). We considered statistical significance to be defined as P < 0.05.