Loading...
Loading...
1 min read
A study reveals that individuals who take longer to reach the REM stage of sleep show higher levels of toxic proteins associated with Alzheimer’s disease. Detecting and treating these disruptions early could help reduce the risk of developing the condition.
Recent research indicates that both the quality and duration of sleep can influence the likelihood of developing Alzheimer’s disease. A new study suggests that a prolonged delay in reaching the rapid eye movement (REM) stage of sleep may be an early indicator of the disease. REM sleep follows three progressively deeper non-REM stages, typically taking at least 90 minutes to complete depending on age. In general, older adults require more time to enter REM sleep. REM sleep also plays a crucial role in memory processing, particularly for emotionally significant experiences. A delay in reaching this stage interferes with memory consolidation, affecting learning and recall. Insufficient or delayed REM sleep can also increase cortisol levels, which in turn may damage the hippocampus—a key structure involved in memory formation.
Now, new data suggests that disruptions in REM sleep could be an early sign of future dementia development. The study, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, analyzed 128 people with an average age of 70 at the China-Japan Friendship Hospital in Beijing. The participants included individuals with Alzheimer’s, people with mild cognitive impairment (a common precursor to the disease), and those with normal cognitive function. During the overnight sleep study, the researchers measured brain activity, eye movement, heart rate, and breathing patterns. They then classified the participants into two groups: those who entered REM sleep early (in less than 98 minutes after falling asleep) and those who experienced a significant delay (more than 193 minutes to reach REM).
The findings revealed that people with Alzheimer's were more likely to experience delayed REM sleep. Additionally, they showed higher concentrations of amyloid and tau proteins—two toxic compounds associated with the disease. Specifically, those with delayed REM sleep had 16% more amyloid and 29% more tau compared to the early REM group. Furthermore, their levels of brain-derived neurotrophic factor (BDNF)—a beneficial protein that decreases in Alzheimer's—were 39% lower. To reduce the risk of Alzheimer's, it is recommended to maintain healthy sleep habits that promote REM sleep, such as treating sleep apnea, moderating alcohol consumption, and consulting a doctor about medications that may disrupt sleep cycles.
Research suggests that melatonin may improve REM sleep and reduce the accumulation of amyloid and tau in animal studies. Similarly, certain insomnia medications that promote REM sleep have been shown to decrease the buildup of harmful proteins. Addressing sleep disturbances early on could give doctors an opportunity to mitigate the neurodegenerative processes underlying Alzheimer's and offer hope to at-risk populations.
Sources