In conducting the study, the team monitored the circadian rhythms of 189 cognitively normal, older adults with a mean average of 66 from Washington University's Knight Alzheimer’s Disease Research Center. All of them wore devices like exercise trackers for seven to 14 days and accomplished a detailed sleep diary each morning to monitor how dispersed rest and activity were throughout a day. Some had positron emission tomography (PET) scans in search for Alzheimer’s-related amyloid plaques in their brains, while others had their cerebrospinal fluid tested for Alzheimer’s-related proteins. Some also took both scans and spinal fluid testing.
"In this new study, we found that people with preclinical Alzheimer's disease had more fragmentation in their circadian activity patterns, with more periods of inactivity or sleep during the day and more periods of activity at night," said Yo-El Ju, an assistant professor of neurology.
Results revealed that 139 of the participants were clear of amyloid protein that indicates preclinical Alzheimer’s. Although the majority of them had regular sleep/wake cycles, some had body clock disturbances that were associated with older age, sleep apnea, or other causes. Among the 50 participants who either had abnormal brain scans or abnormal cerebrospinal fluid, all of them experienced great disturbances in their internal body clocks, which were identified by the amount of rest they got at night and how active they were during the day. Disruptions in the circadian rhythm continued even after the researchers statistically controlled for sleep apnea, age, and other factors.
Moreover, it was revealed that those who experienced short activity and rest spurts during day and night were more probable of showing evidence of amyloid buildup in their brains.
"It wasn't that the people in the study were sleep-deprived," said first author Erik S. Musiek, an assistant professor of neurology. "But their sleep tended to be fragmented. Sleeping for eight hours at night is very different from getting eight hours of sleep in one-hour increments during daytime naps."
The findings of the study, published in the journal JAMA Neurology, support a previous mouse study of Musiek and Geraldine J. Kress that analyzed the circadian rhythm disturbances of Alzheimer's. In this study, they disabled the genes that control the circadian clock to interrupt the rats' circadian rhythms. They found that after two months, mice with disrupted circadian rhythms had more amyloid build ups compared to mice with normal rhythms. Moreover, the mice also displayed changes in the normal, daily rhythms of amyloid protein in the brain.
A person with Alzheimer's disease may find it hard to have enough of sleep and may wake up frequently during the night. Some people use medications for sleep changes; however, these cause serious side effects. On the other hand, natural treatments for sleep changes do not cause side effects but aim to enhance sleep routine and sleeping environment and lessen daytime napping. To promote rest for a person with Alzheimer's, do the following:
(Related: Can’t Stay Asleep? 26 Tips to Help you Sleep Tight)
Read more stories on age-related diseases at Longevity.news.
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