People tend to find it harder to fall asleep and staying asleep as they get older.
Results of the 2017 National Poll on Healthy Aging revealed that 46 percent of older adults have trouble sleeping at least once per week while 15 percent said they have sleep problems for at least three nights per week.
A new study now reveals why older people tend to have difficulty sleeping. The study, which used aging mice, offers hints at how age affects people's ability to get good slumber at night.
The circadian clock is essentially the body's 24-hour internal clock that runs in the background of the brain and cycles between alertness and sleepiness, and regular intervals.
In the new study published in the journal Neurobiology of Aging, Gurprit Lall, from the University of Kent, and colleagues identified how age impairs the ability of the circadian clock in mammals to reset itself when exposed to light, leading to disruptions in sleeping patterns.
Lall and colleagues found that aging causes a significant reduction in sensitivity to light in the part of the brain that regulates circadian rhythms, the suprachiasmatic nucleus or SCN located in the brain's hypothalamus.
The researchers found that a glutamate receptor or NMDA, which transmits light information, becomes less effective in resetting the body's circadian clock as part of the aging process. An NMDA receptor subunit is also reduced in older mammals.
The researchers concluded that the aging SCN suffer from a structural reorganization of its light-receiving components. This affects its function in setting and maintaining stable circadian rhythm.
The researchers said that the findings can help address problems with the circadian clock in older people.
"By establishing the significant changes in NMDA receptor configuration through age and the impact on circadian synchronization, we have uncovered a novel therapeutic target for the potential treatment of circadian misalignment in aged individuals," the researchers wrote in their study.
Health Hazards Of Sleep Problems
Matthew Walker, director at the University of California Berkeley's Center for Human Sleep Science who has written a book about the science of sleep, cited a link between sleep deprivation and a range of health problems, which include diabetes, cancer, Alzheimer's disease and poor mental health.
Numerous studies have also shown the hazards of sleep problems. A 2017 study, for instance, showed that sleep deprivation can cause the brain to cannibalize itself. Poor sleep is also associated with increased risk for Alzheimer's disease.