One factors that could explain this change in sleep architecture is a change in circadian rhythm, which regulates sleep. A disruption of the circadian rhythm would therefore generate sleep disturbances. Some studies show that people with AD have a delayed circadian rhythm, whereas in normal aging we will find an advanced circadian rhythm.
Waking up in the middle of the night to use the bathroom is such a common problem it has a name: nocturia . As we get older, our bodies' ability to hold fluids for long periods decreases, thanks to a decline in antidiuretic hormones. According to the National Sleep Foundation, 65 percent of older adults have sleep deprivation resulting from waking up frequently to use the bathroom.
Another systematic review noted 7-16% of young adults suffer from delayed sleep phase disorder. This disorder reaches peak prevalence when people are in their 20s. Between 20 and 26% of adolescents report a sleep onset latency of >30 minutes. Also, 7-36% have difficulty initiating sleep. Asian teens tend to have a higher prevalence of all of these adverse sleep outcomes than their North American and European counterparts.
What to do: See your dentist for an exam. Bite problems are often a cause of bruxism, and it's a good idea to check for damage to your teeth. It's likely she'll suggest lifestyle changes, such as cutting out alcohol before bed. If you chew gum, stop -- the habitual chewing action can make it more likely you'll grind your teeth at night. Wearing a dental guard or splint at night is usually the next step for bruxism. Your dentist will fit you with a device that prevents your jaw from clenching. Other treatments include Botox injections to the jaw muscle, and a biofeedback device called Grindcare.