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Published on: November 14, 2017
Causal associations between sleep apnea and dementia: a two-sample Mendelian randomization study
Lirong Zhao1, Yamin Xu2, Lu Xia3
1Department of Neurology, Huadong Hospital Affiliated to Fudan University, Shanghai, China.
Archives of Medical Science : AMS
|June 17, 2026
Summary
This study used Mendelian randomization to explore causal links between sleep apnea and dementia. Findings reveal bidirectional genetic associations, suggesting complex interplay between obstructive sleep apnea and dementia subtypes.
Area of Science:
- Neuroscience
- Genetics
- Sleep Medicine
Background:
- Observational studies suggest a link between sleep apnea and dementia, but causality remains unclear.
- Investigating bidirectional relationships is crucial for understanding disease mechanisms.
Purpose of the Study:
- To investigate the bidirectional causal relationships between sleep apnea and various dementia types using Mendelian randomization (MR).
- To explore genetic associations between obstructive sleep apnea (OSA) and general sleep apnea with dementia subtypes.
Main Methods:
- Utilized summary-level data from genome-wide association studies (GWAS) for sleep apnea and dementia.
- Employed two-sample Mendelian randomization with inverse variance weighted (IVW) as the primary method.
- Conducted sensitivity analyses including MR-PRESSO and Cochran's Q test to ensure robustness.
Main Results:
- Forward MR indicated OSA was associated with reduced unspecified dementia risk.
- Reverse MR showed general dementia associated with reduced OSA and generalized sleep apnea risk.
- Alzheimer's dementia also showed associations with reduced sleep apnea risk.
Conclusions:
- Revealed complex, bidirectional genetic associations between sleep apnea and dementia subtypes.
- Provides novel genetic insights into the intricate relationship between sleep apnea and dementia.
- Highlights the importance of considering subtype-specific associations in sleep apnea and dementia research.
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