Evaluating the Bidirectional Causal Association Between Daytime Napping and Alzheimer's Disease Using Mendelian...

Area of Science:

• Neuroscience
• Genetics
• Epidemiology

Background:

• Previous studies on daytime napping and Alzheimer's disease (AD) have yielded conflicting results.
• The causal relationship between daytime napping and cognitive decline remains unclear.

Purpose of the Study:

• To investigate the potential causal association between daytime napping and Alzheimer's disease (AD).

Main Methods:

• A bidirectional Mendelian randomization (MR) analysis was conducted.
• Utilized large-scale genome-wide association study (GWAS) datasets for daytime napping and AD.
• Employed five MR methods: IVW, weighted median, MR-Egger, MR-PRESSO, and contamination mixture.

Main Results:

• The MR analysis indicated a significant causal effect of AD on daytime napping (IVW: beta = -0.006, p = 0.002).
• No significant causal association was found between daytime napping and AD (IVW: OR = 0.76, p = 0.14).

Conclusions:

• Alzheimer's disease (AD) causally influences daytime napping habits.
• Daytime napping does not appear to have a causal effect on the development of AD.
• Findings align with other MR studies suggesting AD impacts sleep, rather than vice versa.