A study in China has looked into the effects of sleep on the risk of dementia. The study is important for the country as it has the highest rates of dementia globally. Reports have found that dementia affects about 6% of older adults. However, most research on the disease has been on Caucasian people in North America and Europe despite China having the biggest dementia demographic.
Excessive sleep causes cognitive decline
A study in China found that people who slept too early and for longer were more likely to develop dementia. Furthermore, researchers found that even those who didn’t develop dementia during the study were likely to have cognitive decline if they slept too much. However, these findings only applied to people aged 60 to 74 and men.
This study is not the first to evaluate his sleep affects cognition. Many studies have found that sleeping too little could also increase the risk of dementia. These findings are concerning as many people experience changes in sleep quality and tune as they age.
Older adults in rural China tend to wake up earlier and sleep later than their white counterparts. This difference in sleep patterns could explain why they are more like to develop dementia.
How researchers conducted the study
For their study, researchers gathered 3274 participants from the Shandong Yanggu Study of Aging and Dementia. Then, the team conducted various tests on the participants in 2024. These tests were lab testing, in-person interviews, and clinical testing.
The study continued in 2018 with the remaining 1982 participants. The team examined their sleep patterns and compared them from the start of the study. Among the respondents, 97 had developed dementia.
The research concluded that people who slept over eight hours were at a higher risk for dementia than those who got seven to eight hours of sleep. In addition, the probability was twice as much for people who slept after 9 pm than those who did after 10 pm.
Interestingly, the researchers only found a cognitive decline in those between 60 and 74 who didn’t have dementia. Those who were 75 and above did not experience cognitive decline. The findings also showed that men were more likely to experience cognitive decline.
