Related Experiment Video
Updated: Jul 19, 2025
08:43
Application of Granger Causality Analysis of the Directed Functional Connection in Alzheimer's Disease and Mild Cognitive Impairment
Published on: August 7, 2017
7.9K
Causal relationships between delirium and Alzheimer's disease: a bidirectional two-sample Mendelian randomization
Jiang Zheng1, Xiaohui Du1, Liu Yang2
1Department of Anesthesiology, Chongqing Emergency Medical Center, Chongqing University Central Hospital, School of Medicine, Chongqing University, Chongqing, China.
European Journal of Medical Research
|August 7, 2023
Summary
This study found no causal link between delirium and Alzheimer's disease (AD). However, Alzheimer's disease (AD) appears to be a risk factor for developing delirium, suggesting a one-way causal relationship.
Area of Science:
- Neuroscience
- Genetics
- Epidemiology
Background:
- Observational studies suggest a link between delirium and increased Alzheimer's disease (AD) risk, but causality is unclear.
- The potential for reverse causation, where AD increases delirium risk, also exists.
Purpose of the Study:
- To investigate the bidirectional causal relationship between delirium and Alzheimer's disease (AD) using Mendelian randomization.
Main Methods:
- A bidirectional two-sample Mendelian randomization (MR) analysis was conducted.
- Genome-wide association study summary statistics for delirium and AD phenotypes were utilized.
- Inverse-variance weighted (IVW) and other MR methods assessed causality, with heterogeneity and pleiotropy tests.
Main Results:
- Genetically predicted delirium was not associated with an increased risk of AD.
- Conversely, genetically predicted AD was significantly associated with an increased risk of delirium (IVW OR 1.32, P=3.91E-04).
Conclusions:
- There is no evidence of bidirectional causality between delirium and AD.
- AD is identified as a potential causal risk factor for delirium.
- Delirium does not appear to increase the risk of developing AD.
Related Concept Videos
01:26Alzheimer's Disease: Overview
521
Alzheimer's Disease (AD) is a continually advancing neurodegenerative disorder, distinguished by escalating memory loss, cognitive dysfunction, and dementia. The disease unfolds in three stages: preclinical, mild cognitive impairment (MCI), and dementia. Its onset is insidious, and the progression gradual, with the cause not well explained by other disorders.
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ...
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ...
521
01:21Causality in Epidemiology
472
Causality or causation is a fundamental concept in epidemiology, vital for understanding the relationships between various factors and health outcomes. Despite its importance, there's no single, universally accepted definition of causality within the discipline. Drawing from a systematic review, causality in epidemiology encompasses several definitions, including production, necessary and sufficient, sufficient-component, counterfactual, and probabilistic models. Each has its strengths and...
472
01:28Criteria for Causality: Bradford Hill Criteria - II
366
The Bradford Hill criteria serve as guidelines for establishing causative links in epidemiological research. Beyond Strength, Consistency, Specificity, and Temporality, key criteria also include Biological Gradient, Plausibility, Coherence, Experiment, and Analogy. These principles assist scientists in assessing the likelihood of causation in complex biological contexts. Below is a summary of these concepts:
366
01:29Biological Causes of Schizophrenia
103
Schizophrenia, a severe psychiatric disorder, arises from a complex interplay of biological factors, including genetic predisposition, structural brain abnormalities, neurotransmitter dysregulation, and developmental irregularities. These factors collectively contribute to the onset and progression of the disorder, which typically manifests in late adolescence or early adulthood.
Genetic Factors in Schizophrenia
The genetic basis of schizophrenia is strongly supported by family and twin...
Genetic Factors in Schizophrenia
The genetic basis of schizophrenia is strongly supported by family and twin...
103
01:27Confounding in Epidemiological Studies
189
Confounding in statistical epidemiology represents a pivotal challenge, referring to the distortion in the perceived relationship between an exposure and an outcome due to the presence of a third variable, known as a confounder. This variable is associated with both the exposure and the outcome but is not a direct link in their causal chain. Its presence can lead to erroneous interpretations of the exposure's effect, either exaggerating or underestimating the true association. This...
189
01:16Experimental Designs
11.6K
An experimental design is a systematic process that allows researchers to evaluate the relationship between dependent and independent variables. There are three widely used types of experimental design - pre-experimental design, true experimental design, and quasi-experimental design. In pre-experimental design, the researcher compares the data before and after some interventions or treatments. The true-experimental design has more than one purposefully created group, a commonly measured...
11.6K