Causal Relationship between Alzheimer's disease and Intracerebral hemorrhage: a two-way Mendelian randomization analysis

Abstract The relationship between Alzheimer's disease (AD) and the risk of Intracerebral hemorrhage (ICH) is still debatable. The aim of this study was to investigate the potential causal relationship between them. This study was conducted in a two-sample Mendelian randomization (MR) design using summary statistics from an independent genome-wide association study (GWAS). The selected exposure factor was AD. And different genetic predispositions for AD were categorized into two subgroups. The outcome was ICH. the main analytical tool used was the inverse variance weighting (IVW) method, supplemented by sensitivity analyses. The findings suggest a positive association between AD and ICH. The level of genetic prediction of AD was consistently positively correlated with ICH, as evidenced by IVW (odds ratio [OR] = 1.33E + 12; P < 0.01). These associations were further supported by the results of all sensitivity analyses. In addition, Illnesses of mother: Alzheimer's disease/dementia was associated with ICH (IVW: OR = 5.947; P < 0.05). AD and ICH have a unidirectional causal relationship, and illnesses of mother is a major factor with ICH, whereas Alzheimer's disease or a family history of Alzheimer's disease is not.