APOB and Alzheimer disease: Intriguingly, our MR analysis provided evidence that AD-related neuropathology leads to disruption of lipid metabolism, and increased levels of cholesterol, LDL, and apolipoprotein B. Previously, high cholesterol, and LDL have been implicated as risk factors for AD [65] and here we show evidence also for a reverse relationship, pointing to a vicious cycle that fuels neurodegeneration.