Good Sleep Does Get Tougher With Age
Most people see their sleep habits shift as they age, but a new review suggests that some seniors lose the ability to get deep, restorative rest.
And that can come with health consequences, said review author Bryce Mander, a sleep researcher at the University of California, Berkeley.
Sleep “fragmentation” has been linked to a number of medical conditions, including depression and dementia, Mander said. People with fragmented sleep wake up multiple times during the night, and miss out on the deep stages of sleep.
It is true that medical conditions, or the treatments for them, can cause sleep problems, according to Mander.
But poor sleep can also contribute to disease, he added.
Take dementia, for example. Research suggests there is a “bi-directional” link between sleep disruptions and the dementia process, said Joe Winer, another Berkeley researcher who worked on the review.
That is, dementia often causes sleep problems; poor sleep, in turn, may speed declines in memory and other mental skills. According to Winer, animal research suggests that deep sleep helps “clear” the brain of the amyloid-beta proteins that build up in people with dementia.
So there may be a “vicious cycle,” Winer said, where dementia and poor sleep feed each other.
Similar vicious cycles may be at work with other diseases, too, Mander said. He also stressed, though, that some shifts in sleep habits may be perfectly normal.
Older people are famously prone to being “early to bed, early to rise.” They may also sleep a little less than they used to in their younger days. And that may be fine, the researchers said.
“We don’t want to create a panic that if you’re sleeping a little less than you used to, you’re going to develop dementia,” Mander said.
But, he added, it is important to recognize sleep as one of the lifestyle factors critical to good health — right along with exercise and a healthy diet.
In fact, Mander noted, one reason that regular exercise keeps us healthy is that it can support better-quality sleep.
“Why do some people age more ‘successfully’ than others?” he said. “We think sleep is one of the factors.”
But people should not wait until old age to care about sleep. According to Mander’s team, people often start losing the capacity for deep sleep in middle age, and that decline continues over the years.
What’s not clear yet, Mander said, is whether good sleep habits earlier in life help protect people from sleep problems in old age.
The review, which analyzed medical literature on the topic of sleep and aging, was published online April 5 in the journal Neuron.