FollowAs people advance in age, they have a tendency to sleep less and to wake earlier in the morning. Alzheimer’s patients are particularly affected by sleep deprivation. Scientists attempting to uncover the reasons why elderly sleep less and reached some conclusions.
People are equipped with a set of inhibitory neurons that die off as we age. Previous research on animals show this result and it applies to humans as well.The discovery of the specific type of neurons responsible for sleep cycles was done in 1996. Scientists studied how rats have a ‘sleep switch’ that is deregulated once the inhibitory neurons die off.
“On average, a person in his 70s has about one hour less sleep per night than a person in his 20s,” explains senior author Clifford B. Saper, MD, PhD, Chairman of Neurology at BIDMC and James Jackson Putnam Professor of Neurology at Harvard Medical School. “Sleep loss and sleep fragmentation is associated with a number of health issues, including cognitive dysfunction, increased blood pressure and vascular disease, and a tendency to develop type 2 diabetes. It now appears that loss of these neurons may be contributing to these various disorders as people age.”
Disparate scientific results seems to be connected. Recently other scientists discovered that sleep disorders increase suicide risks for older adults.
Wearable devices helped scientists understand why elderly sleep less
Without taking into account Alzheimer’s patients, researchers found that patients with low levels of ventrolateral preoptic neurons suffer from sleep fragmentation. “The fewer the neurons, the more fragmented the sleep became,” Saper added.
The researchers investigated some members from a community formed to study dementia and aging. From the Rush and Aging Project, the researchers selected data from 45 people who wore devices on their hands during their last period of life. After the patients deceased, scientists analyzed their brains, which were donated voluntarily. That is how they reached the conclusion that inhibitory neurons dying out are responsible for sleep deprivation.
Based on the findings answering why elderly sleep less, now researchers have to find out new ways of helping elders have a good night of sleep and inherently avoid developing neurological conditions. More so now, as sleep deprivation increases suicide risks, according to other research.
The results of the study were published in the journal Brain under the title “Sleep is related to neuron numbers in the ventrolateral preoptic/intermediate nucleus in older adults with and without Alzheimer’s disease”
