World Sleep Day 2025: Make Sleep Health a Priority
Sleep is an integral part of health - just like nutrition, exercise, and social connections (1,2). Sleep helps clear waste from the brain, strengthens immunity, and even supports memory, learning, and overall well-being (3–6). Poor sleep has been linked to cognitive decline, infections, and an increased risk of chronic diseases such as diabetes and cardiovascular diseases (3,7–13).
Healthy sleep isn’t just about quantity - it’s about quality, timing, and regularity (14). We all ought to prioritise our sleep by setting a consistent bedtime, creating a restful environment, and aiming for at least 7 hours a night; less than 6 has been associated with a build-up of beta-amyloid, the protein related to Alzheimer’s (15).
Highlighting how sleep plays a crucial role in maintaining cognitive and brain health across the lifespan is a new study by the researchers at Imperial WHOCC linking obstructive sleep apnoea and increased dementia risk in men (16). This systematic review, now available as a pre-print, suggests obsructive sleep apnoea may play a significant role in cognitive decline and Alzheimer’s. The study underscores the importance of early diagnosis and treatment of sleep disorders as a potential preventative measure. Stay tuned for the full publication: Tabche et al. (2024) The Association between Obstructive Sleep Apnoea and Dementia in Men: A Systematic Review. SSRN Journal. http://dx.doi.org/10.2139/ssrn.4880347 .
Listen in to our interview this World Sleep Day with Professor Guy Leschziner, a leading neurologist and sleep specialist, as we explore sleep's connection to brain health, the role of the glymphatic system in clearing waste, and the impact of sleep disruption on dementia and cardiovascular disease. Moreover, we’ll tackle some of the biggest misconceptions around sleep and speak about interesting conditions you may not have heard of.
Authored and interviewed by Emmanuel Urama, Imperial WHOCC Intern
Edited by: Rachel Barker, Imperial WHOCC Support Officer
⭐️ Starting this World Sleep Day, let’s make sleep a health priority! ⭐️
References:
1. Cassidy S, Chau JY, Catt M, Bauman A, Trenell MI. Cross-sectional study of diet, physical activity, television viewing and sleep duration in 233 110 adults from the UK Biobank; the behavioural phenotype of cardiovascular disease and type 2 diabetes. BMJ Open [Internet]. 2016 Mar 1;6(3):e010038. Available from: http://bmjopen.bmj.com/content/6/3/e010038.abstract
2. Hale L, Troxel W, Buysse DJ. Sleep Health: An Opportunity for Public Health to Address Health Equity. Annu Rev Public Health. 2020 Apr 2;41(1):81–99.
3. Nedergaard M, Goldman SA. Glymphatic failure as a final common pathway to dementia. Science (1979). 2020 Oct 2;370(6512):50–6.
4. Reyes-Resina I, Samer S, Kreutz MR, Oelschlegel AM. Molecular Mechanisms of Memory Consolidation That Operate During Sleep. Front Mol Neurosci. 2021 Nov 18;14.
5. Ju YES, Lucey BP, Holtzman DM. Sleep and Alzheimer disease pathology—a bidirectional relationship. Nat Rev Neurol. 2014 Feb 24;10(2):115–9.
6. Haspel JA, Anafi R, Brown MK, Cermakian N, Depner C, Desplats P, et al. Perfect timing: circadian rhythms, sleep, and immunity — an NIH workshop summary. JCI Insight. 2020 Jan 16;5(1).
7. Lim ASP, Kowgier M, Yu L, Buchman AS, Bennett DA. Sleep Fragmentation and the Risk of Incident Alzheimer’s Disease and Cognitive Decline in Older Persons. Sleep. 2013 Jul 1;36(7):1027–32.
8. Wennberg A, Wu M, Rosenberg P, Spira A. Sleep Disturbance, Cognitive Decline, and Dementia: A Review. Semin Neurol. 2017 Aug 24;37(04):395–406.
9. Bonilla-Jaime H, Zeleke H, Rojas A, Espinosa-Garcia C. Sleep Disruption Worsens Seizures: Neuroinflammation as a Potential Mechanistic Link. Int J Mol Sci. 2021 Nov 20;22(22):12531.
10. Koo DL, Nam H, Thomas RJ, Yun CH. Sleep Disturbances as a Risk Factor for Stroke. J Stroke. 2018 Jan 31;20(1):12–32.
11. Covassin N, Singh P, Somers VK. Keeping Up With the Clock. Hypertension. 2016 Nov;68(5):1081–90.
12. Itani O, Jike M, Watanabe N, Kaneita Y. Short sleep duration and health outcomes: a systematic review, meta-analysis, and meta-regression. Sleep Med. 2017 Apr;32:246–56.
13. Covassin N, Singh P. Sleep Duration and Cardiovascular Disease Risk. Sleep Med Clin. 2016 Mar;11(1):81–9.
14. World Sleep Day Toolkit [Internet]. 2025 [cited 2025 Mar 14]. 2025 Theme: Make Sleep Health a Priority. Available from: https://worldsleepday.org/toolkit#:~:text=2025%20Theme%3A%20Make%20Sleep%20Health%20a%20Priority&text=The%20scientific%20evidence%20is%20clear,important%20as%20nutrition%20and%20exercise!
15. Insel PS, Mohlenhoff BS, Neylan TC, Krystal AD, Mackin RS. Association of Sleep and β-Amyloid Pathology Among Older Cognitively Unimpaired Adults. JAMA Netw Open. 2021 Jul 23;4(7):e2117573.
16. Tabche C, Pillay NC, Atwan Z, Raheem M, Dubois E, Rawaf S. The Association between Obstructive Sleep Apnoea and Dementia in Men: A 2023 Systematic Review. 2024.