Age and sleep are closely related, and many people will notice a significant decline in the quality of sleep as they grow older. According the Division of Sleep Medicine at Harvard Medical School, sleep patterns change throughout life, and for most of us, the amount of time we spend sleeping each day slowly decreases as we age.
Two main types of sleep
There are two main types of sleep: REM (rapid-eye movement) and NREM (non-rapid-eye movement). REM sleep is associated with dreaming, and NREM sleep occurs in three stages-N1 (light sleep), N2 (slightly deeper), and N3 (slow-wave deep sleep). Sleep cycles are composed of REM and NREM sleep, typically lasting for about 50 minutes in children and 90 minutes in adults. The main difference between a child’s sleep cycle and an adult’s is the amount of time spent in the N3 stage-children spend far more time in this slow-wave deep sleep than adults, meaning that adults wake more easily and frequently.
Sleep rhythms
Another factor that affects sleep patterns is the circadian pacemaker. Simply put, circadian rhythms determine when the body begins to feel sleepy and when it awakens. These rhythms shift as we age. Children, adults, and seniors experience different sleep patterns based on many factors.
Children and sleep
Newborns typically spend between 16 and 20 hours sleeping each day. The hours a child spends sleeping gradually diminishes to about 11 hours by the time they reach the age of four, and continues to decline until the adolescent years, when a teenager requires only nine hours of sleep.
Children and teens generally spend more time in a deep sleep than adults. The most obvious change from childhood to adolescence is in the circadian rhythm-teens often seem tired or experience trouble sleeping due to the change in their internal clocks. Due to these changes in rhythm, a teen’s body wants to be awake later into the night and sleep later in the morning. These late nights in conjunction with the need to wake up early for school causes shortened sleep duration, which can leave a teen feeling sleepy, tired, and never fully rested. Check out additional information about children and sleep here.
Adults and sleep
According to WebMD, the most drastic sleep changes occur gradually between the ages of 19 and 60. By the age of 20, the amount of time a person spends in deep sleep is cut in half (children generally spend 50% of their night in deep sleep). It is not uncommon for people to completely lose the ability to reach that type of deep sleep by the age of 40. The challenges of adulthood (careers, bills, marriage, children) often cause stress that affects sleep.
Women typically face more sleep problems than men due to hormonal and mental changes connected with pregnancy, menopause, and parenthood. Stress and worry from parenting are often a cause of insomnia and disrupted sleep in women.
Seniors and sleep
Seniors often experience more difficulty getting to sleep and staying asleep. They experience shorter periods of slow-wave sleep (the deep sleep with no dreaming), which means they spend more time in a lighter sleep and wake up more frequently. Circadian rhythms change more during senior years, making a person tired earlier in the evening, thus leading them to go to bed earlier at night and rise earlier in the morning.
Although some sleep problems that affect seniors can be attributed to growing older, most arise from chronic medical conditions. Health issues such as arthritis, congestive heart failure, gastroesophageal reflux disorder, sleep apnea, restless leg syndrome, and periodic limb movement can all impact sleep patterns. Insomnia can also be a side effect of many medications used to treat these health problems. Behavioral, lifestyle, and social changes such as the death of a loved one, retirement, or moving into a nursing home can also negatively impact sleep patterns (learn more about good sleep habits here).
Concerned that you or a loved one (child, spouse or parent) isn’t sleeping properly? Take our sleepiness quiz and discuss your results with your doctor.
Sources:
http://healthysleep.med.harvard.edu/healthy/science/variations/changes-in-sleep-with-age
http://www.webmd.com/sleep-disorders/living-with-insomnia-11/sleep-changes?page=2
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