A late entry into paradoxical sleep, where dreams arise, could be an early indicator of Alzheimer’s disease, according to a study.
- A study reveals that the delay in paradoxical sleep could be an early indicator of Alzheimer’s disease. People taking more than 193 minutes to reach this phase had increased levels of amyloid and tau protein, as well as a decrease in the BDNF neurotrophic factor.
- These results suggest that sleep abnormalities could report brain changes long before the appearance of cognitive symptoms.
- Preventive approaches, such as the treatment of sleep disorders, could thus play a key role in the fight against Alzheimer’s.
Could the time to reach dreams be a cognitive decline signal? A team of researchers has highlighted a potential link between the speed of paradoxical coming into sleep (also called REM, for Rapid Eye Movement) and the risk of developing Alzheimer’s disease. Their study, published in the journal Alzheimer’s & Dementiareveals that people taking longer to reach this sleep phase have increased levels of protein associated with the disease.
The implications of a disturbed sleep cycle
Sleep follows a specific cycle, passing through several phases before reaching paradoxical sleep, where dreams arise. This cycle, which is repeated several times a night, is essential for the consolidation of memory. “The delay in paradoxical sleep interferes with the learning and memorization process”indicate scientists from the University of California in San Francisco, in a press release.
As part of their work, the researchers recruited 128 adults to various cognitive capacities. They combined brain imagery, sleep studies and blood analyzes to establish an association between sleep patterns and biological markers of Alzheimer’s disease. The results show that participants putting more than 193 minutes to sleep paradoxical had 16 % more amyloid protein and 29 % more tau protein, key indicators of the disease. In addition, their level of neurotrophic factor derived from the brain (BDNF), essential to neuronal health, was 39 %lower.
Towards new therapeutic tracks
The study suggests that paradoxical sleep abnormalities may appear before the first cognitive disorders, which could thus offer a new opportunity for early screening. Drugs promoting paradoxical sleep, like melatonin, could also have a protective effect against the accumulation of neurotoxic proteins in question.
Finally, the authors insist on the importance of managing sleep disorders. “Treating sleep apnea and reducing alcohol consumption are part of the simple measures to preserve a healthy sleep cycle”and thus prevent neurodegenerative pathologies like Alzheimer, they conclude.
