A recent study suggests that delays in the REM (rapid eye movement) phase of sleep may serve as an early indicator of Alzheimer’s disease risk.
REM sleep, occurring after three stages of non-REM sleep, is critical for memory consolidation and learning. Dr Yue Leng from the University of California, San Francisco, explained, “Delayed REM sleep disrupts the brain’s ability to consolidate memories, interfering with the process that promotes learning and memory.” This delay elevates cortisol levels, a stress hormone that adversely affects the hippocampus, a brain region essential for retaining information.
Published in Alzheimer’s and Dementia: The Journal of the Alzheimer’s Association, the study involved 128 participants with an average age of 70. Among them, half had Alzheimer’s disease, one-third had mild cognitive impairment, and the rest demonstrated normal cognitive function. By monitoring brain activity, eye movements, and other physiological markers overnight, researchers found a strong correlation between delayed REM sleep and elevated levels of toxic amyloid and tau proteins, hallmarks of Alzheimer’s disease. The study showed 16% higher amyloid, 29% higher tau, and 39% lower levels of brain-derived neurotrophic factor (BDNF), a key molecule for neuronal health, in individuals with delayed REM sleep.
Potential interventions, such as melatonin and certain insomnia medications, have shown promise in animal studies, reducing tau and amyloid accumulation and improving REM sleep quality.
Doctors recommend maintaining healthy sleep habits, avoiding alcohol, and treating conditions like sleep apnea to lower Alzheimer’s risk. Additionally, Dr. Dantao Peng of the China-Japan Friendship Hospital in Beijing noted,
Disclaimer: Medical research statistics represent general trends and may not apply to everyone. Always consult a healthcare professional for personalized advice on your health.
