Anaesthesia and delirium: a Mendelian randomization study

Background Delirium is a frequent complication in hospitalized older adults post-surgery associated with adverse outcomes. Although anaesthesia is traditionally linked to increased delirium risk, the causal relationship remains uncertain. Methods We conducted Mendelian randomization (MR) analyses using genome-wide association studies (GWAS) summary statistics to explore the causal effects of different anaesthesia types (general, regional, and local) on delirium risk. We employed the weighted median, MR-Egger, and MR-PRESSO methods for estimation and conducted sensitivity analyses to address pleiotropy and heterogeneity. Results Genetically determined anaesthesia types showed no significant causal effect on delirium risk. Sensitivity analyses confirmed the robustness of these findings, with no evidence of horizontal pleiotropy or significant heterogeneity. Conclusions Mendelian randomization provides strong evidence against a causal link between genetically determined anaesthesia and increased delirium risk.