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Researchers discover another possible reason for insomnia

Created date

October 22nd, 2014
senior couple sleeping
senior couple sleeping

new study may help explain why some seniors have trouble sleeping.

According to a team of researchers from Beth Israel Deaconess Medical Center in Boston and the University of Toronto, seniors in their 70s sleep about one hour less each night than people in their 20s. Some have problems falling asleep, staying asleep, or waking too early. In seniors with dementia-related illnesses, sleep problems can be even more pronounced. Chronic sleep loss has been associated with health problems, including high blood pressure, cardiovascular disease, diabetes, and memory problems.

Insomnia can have many causes such as sleep apnea, restless legs syndrome, or emotional and physical health problems. Sometimes, it is caused by medication side effects. But researchers now believe there may be another reason.

‘Sleep switch’

Previous animal studies had revealed that a certain set of neurons (nerve cells) in the brain function as a sort of “sleep switch,” and that the level of these neurons tends to decrease with age. Researchers wanted to find out if this was also true in humans, so they found a group of study participants who agreed to donate their brains for research upon their deaths.

While the study subjects were alive, they wore devices called actigraphs that measured the amount and quality of nightly sleep they had. The participants also underwent imaging studies that showed how many of the sleep-related neurons were present. Researchers then compared that number to the amount of neurons present after death. They found what they expected—that the level of these neurons were significantly decreased, especially in people whose actigraph readings indicated poor quality sleep and also in people diagnosed with dementia. Scientists expect that these results may contribute to the development of new methods to prevent or reduce sleep problems in seniors.