A recent study has unearthed a worrying connection between poor sleep quality and an increased risk of Alzheimer’s disease. Researchers have found that difficulty in entering the vital REM sleep phase correlates to cognitive deterioration.
REM sleep, known for being the intense, dream-heavy part of sleep, plays a key role in aiding the brain in processing and storing memories. Struggles with attaining this level of rest could hint at early stages of Alzheimer’s, the research indicates.
Published in ‘Alzheimer’s and Dementia,’ the research found that delays in reaching REM sleep—which occurs during the fourth 90-minute cycle of slumber—not only impedes memory formation but can also raise stress hormones. Dr Yue Leng PhD, the paper’s senior author, warned: “The delay in REM sleep disrupts the brain’s ability to consolidate memories by interfering with the process that contributes to learning and memory.”
Part of the team from UCSF Weill Institute for Neurosciences, Dr Leng added, “If it is insufficient or delayed, it may increase the stress hormone cortisol. This can impair the brain’s hippocampus, a critical structure for memory consolidation.”
In the study, conducted by researchers from the China-Japan Friendship Hospital in Beijing, 128 individuals over the age of 70 were invited to stay overnight at their sleep clinic. The participants, a third of whom had mild cognitive impairments, half diagnosed with Alzheimer’s, and the rest with normal cognitive function, had their brain activity measured while they slept.
This included monitoring their brainwaves, eye movements, breathing, and heart rates. Participants were then divided into two groups based on how quickly they reached REM sleep.
Those who reached this crucial sleep stage first typically took 98 minutes, while those with poorer quality sleep took over three hours (198 minutes). Most Alzheimer’s patients fell into the latter group, which also tended to have higher levels of proteins associated with Alzheimer’s and other dementias.
Those with delayed REM sleep had significantly higher levels of amyloid (16%) and tau (29%) than the other group. This research contributes to the growing body of evidence linking sleep quality to dementia risk and could influence further studies into the effect of drugs that aid REM sleep on reducing this risk.
Dr Leng concluded: “Future research should study the effects of certain medications that influence sleep patterns, as these may modify disease progression.”
Recent research has uncovered that treatments for insomnia, which aid in achieving REM sleep, may also decrease tau and amyloid levels in the brain, sparking optimism that sleep therapies could contribute to reducing the risk of dementia. Neurologist Dr Dantao Peng, a senior co-author of the study, said: “This includes treating conditions like sleep apnea and avoiding heavy drinking, since both can interfere with a healthy sleep cycle.
“Patients taking certain antidepressants and sedatives that reduce REM sleep should discuss their concerns with their doctor, if they are worried about Alzheimer’s.”
This story originally appeared on Express.co.uk
