Researchers from the University of California have revealed a link between daytime sleepiness and an increased risk of developing dementia in older women, doubling the risk.
اضافة اعلان
Sleep is essential for nervous system health, cellular regeneration, and enhancing memory storage and the learning of new information. However, dementia can disrupt this process, meaning that even individuals who get eight hours of sleep each night may not experience restful sleep.
The researchers discovered this connection, although they couldn't definitively determine whether poor sleep causes dementia by disrupting waste removal and cellular regeneration in the brain during sleep, or if the gradual decline of the brain leads to poor sleep quality.
Dr. **Yui Ling**, an epidemiologist at the University of California, San Francisco, and a specialist in studying the relationship between sleep and neurodegeneration in older adults, said, "Our study found that sleep problems might be linked to cognitive aging and could serve as an early sign or risk factor for dementia in women in their 80s."
Researchers from both the University of California, San Francisco, and the University of California, San Diego, analyzed data from the Osteoporosis Fracture Study (SOF), which included women aged 65 and older from cities like Baltimore, Minneapolis, Pittsburgh, and Portland between 1986 and 1988.
The study followed 733 women, with an average age of 83 at the start, over several decades. None of the participants showed signs of cognitive impairment at the beginning of the study. The researchers used wrist-worn "actigraph" devices—small devices that measure movement using sensors and continuously record sleep and wake activity.
The women wore these devices for three days at the beginning and end of the study. Researchers also conducted cognitive tests periodically throughout the study.
The results revealed that more than a third of the women experienced a decline in sleep quality, while 21% showed increased daytime sleepiness.
Overall, more than half of the women experienced poor sleep patterns over five years. More than 22% of the women developed cognitive impairment during the follow-up period, while 13% developed dementia.
The researchers found that women who had poor sleep patterns were two to three times more likely to develop dementia compared to those who maintained stable sleep.
Even after adjusting for age, education, and ethnicity, the risk of dementia associated with daytime sleepiness remained double the normal rate.
By using "actigraph" data, researchers could also observe how the women's sleep habits and patterns changed as they aged. The groups that experienced a decline in nightly sleep quality and increased daytime sleepiness showed more daytime sleep, weakened circadian rhythms, and a further decline in sleep quality over time.
Source: *Daily Mail*
