Older adults who slept 9 hours or more also had a decrease in cognitive functions and other health problems, but the researchers did not find the same risk of dementia in this group.
The findings illustrate how important it is to maintain a healthy sleep cycle for adults, especially as they age.
As adults age, it is common for their sleep patterns to change or be disrupted, resulting in longer, shorter or more irregular sleep.
This disorder may be linked to Alzheimer’s disease and other forms of dementiaThis affects the ability of the elderly to remember information, solve problems, and follow up on daily behaviors.
Sleep disturbance can also be caused by depression, heart disease, andBlood vessels and other cases.
A new study from Stanford University provides additional evidence on the relationship between sleep and brain function, as it included the health records of nearly 4,400 patients, aged 65 to 85.
These patients underwent brain scans and other cognitive tests, but were not diagnosed with dementia.
This data was drawn from a long-term investigation of Alzheimer’s disease, which was conducted in 67 clinics in United State Canada, Australia and Japan.
The researchers classified these patients according to the length of time they slept. Sleep times were reported by patients, not measured by a sleep tracker.
The researchers said the recommended sleep time for the elderly is 7 to 8 hours, and 6 hours or less corresponds to short sleep, while 9 hours or more corresponds to long sleep.
In previous studies, patients who slept less than 6 hours and more than 9 hours had worse health outcomes, although short sleep tended to be more risky.
Researchers at Stanford University measured levels of beta-amyloid, a protein in the brain that is usually found in high levels when someone develops Alzheimer’s disease.
In addition, the researchers used several tests of memory, attention, spatial skills, and executive function to determine the patients’ cognitive abilities.
The researchers found that those patients who slept 6 hours or less per night were more likely to develop dementia, and patients who had poor sleep had higher levels of beta-amyloid.
“Amyloid beta is one of the first signs that can be detected in the evolution of amyloid,” Joe Weiner, a postdoctoral researcher at Stanford and lead author of the study told CNN. Alzheimer’s disease“.
“In Alzheimer’s disease, beta-amyloid proteins begin to accumulate throughout the brain, sticking together in plaques.”
The findings in the Stanford study are in line with previous research that has shown that shorter sleep may be linked to dementia.
Researchers at Stanford University found that patients with poor sleep performed worse on memory tests, while those who slept longer (9 hours or more) performed worse on executive function tests, which measure the brain’s ability to switch between different tasks.
Patients with long sleep had normal levels of beta-amyloid, suggesting that their risk of dementia is not as severe as those with poor sleep.
The researchers found that both low and high sleepers were more likely to nap during the day.
In addition, the low and high sleepers had a higher body mass index and depressive symptoms.
“The main takeaway is that it’s important to maintain healthy sleep well into old age,” Weiner told CNN.