July 26, 2007
Older women who have memory problems are more likely than those with intact memories to have problems falling asleep and staying asleep, a new study reports. Such women were more likely to toss and turn in bed at night, and to wake up several times during the night. Understandably, they often felt more drowsy the following day, and were more likely to take naps, further upsetting healthy sleep patterns.
The study appeared in the July 17, 2007, issue of Neurology, the medical journal of the American Academy of Neurology. In the study, researchers followed 2,474 older women over 15 years. None had memory problems at the start of the study, and their average age was 69. They were given regular exams to look for signs of memory loss, and their sleep patterns were also monitored. The researchers found the nearly 25 percent of women who experienced cognitive decline were twice as likely as women without memory problems to experience sleep disturbances.
Women who had memory and cognitive problems "were nearly twice as likely to have difficulty staying asleep and one-and-a-half times as likely to have problems falling asleep," said study author Kristine Yaffe, MD, with the University of California at San Francisco. Women who scored poorly on the memory tests were also more likely to be awake more than 90 minutes during the night and also nearly twice as likely to nap more than two hours a day.
"Perhaps the most likely reason why memory loss may increase the risk of sleep disturbances is that they share a common underlying cause, such as brain changes seen with Alzheimer's disease or other dementias that could increase risk of both memory loss and sleep problems," said Yaffe. "Another reason could be that women with memory problems may also have anxiety or depression that could affect their sleep. While we attempted to adjust for these measures in our study, it's possible that this effect remains."
Yaffe says the group's findings are consistent with prior studies that have found an association between sleep disturbances and poor cognitive function. "But our study raises the possibility that cognitive decline may increase the risk of sleep problems, rather than vice versa."
This study does not mean that an individ.ual who has trouble sleeping will develop cognitive problems or that those who suffer from dementia will necessarily have difficulty sleeping. Sleep problems are extremely common. However, those with dementia are more likely to suffer from sleep problems.
A Common Complaint
Poor sleep and daytime drowsiness are common complaints among older men and women, particularly those with Alzheimer's disease. The fear and anxiety that accompanies a fading memory can keep people up at night. Depression, too, may be an early harbinger of Alzheimer's, and contribute to troubled sleep patterns.
Doctors often prescribe sleep medications, but these and these may provide benefit. Lifestyle measures, such as keeping the elderly out of bed during the day, moderate exercise, and exposure to sunlight, may provide an added boost to promote sound sleep. [See the article, "Lifestyle Measures May Promote Sound Sleep in Alzheimer's."]
If you are worried about memory problems and have trouble falling or staying asleep, consult your physician. Medications and behavioral counseling techniques are available to provide relief.
To learn more, visit www.ALZinfo.org.
Neurology, July 17, 2007. American Academy of Neurology.