Sleep, major depressive disorder and Alzheimer's disease

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 The latest here:

Sleep, major depressive disorder and Alzheimer's disease

 

View ORCID ProfileJian Huang, Verena Zuber, Paul M. Matthews, Paul Elliott, View ORCID ProfileJoanna Tzoulaki, Abbas Dehghan

First published August 19, 2020, DOI: https://doi.org/10.1212/WNL.0000000000010463

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Abstract

Objective To explore the causal relationships between sleep, major depressive disorder (MDD), and Alzheimer's disease (AD).

Methods We conducted bi-directional 2-sample Mendelian randomisation analyses. Genetic associations were obtained from the largest genome-wide association studies currently available in UK Biobank (N = 446,118), the Psychiatric Genomics Consortium (N = 18,759), and the International Genomics of Alzheimer's Project (N = 63,926). We used the inverse variance weighted Mendelian randomisation method to estimate causal effects, and weighted median and MR-Egger for sensitivity analyses to test for pleiotropic effects.

Results We found that higher risk of AD was significantly associated with being a “morning person” (OR = 1.01, p = 0.001), shorter sleep duration (self-reported: β = −0.006, p = 1.9 × 10⁻⁴; accelerometer-based: β = −0.015, p = 6.9 × 10⁻⁵), less likely to report long sleep (β = −0.003, p = 7.3 × 10⁻⁷), earlier timing of the least active 5 hours (β = −0.024, p = 1.7 × 10⁻¹³), and a smaller number of sleep episodes (β = −0.025, p = 5.7 × 10⁻¹⁴) after adjusting for multiple comparisons. We also found that higher risk of AD was associated with lower risk of insomnia (OR = 0.99, p = 7 × 10⁻¹³). However, we did not find evidence either that these abnormal sleep patterns were causally related to AD or for a significant causal relationship between MDD and risk of AD.

Conclusion We found that AD may causally influence sleep patterns. However, we did not find evidence supporting a causal role of disturbed sleep patterns for AD or evidence for a causal relationship between MDD and AD.

• Received August 9, 2019.
• Accepted in final form April 23, 2020.

• Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (CC BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.