The Changes in Our Sleep Pattern as We Age

Many changes occur in our body as we age. Parts of our body and mind begin to deteriorate and other parts slow down.

But how many of these changes are due to the normal aging process and how many of these are due to pathologic conditions?

In the area of sleep, some changes that occur are a result of normal aging and there are many others that are pathologic.

Sleep Requirement for People in Different Ages

When it comes to determining sleep norms, there seems to be a correlation between age, body development, and sleep requirements. The scale is roughly as follows.

• Babies up to two months old require about 16 to 17 hours of sleep each night.
• Babies four months up to one year need about 10 hours of sleep each night, plus two long naps and one short nap during the day.
• Children one year up to 5 years of age generally need 11 hours of sleep each night plus three hours of short and long naps.
• Children between 5 and 15 years of age require 9 to 10 hours of sleep each night.
• Adolescents need about 10 hours sleep each night.
• Adults average about 8 hours sleep each night, but this can vary from as few as 4 to 6 hours, to as many as 9 to 10 hours.

Brain Waves

As we grow, our brain waves change, both in wake and in sleep. The alpha activity decreases, and in particular brain parts there is an increase in slow brain wave activity. Actually, slowing of the Electroencephalogram (EEG) is very common and has little pathologic significance in older, non-demented individuals.

Changes in Sleep Architecture

There are some changes in sleep architecture and in quality of sleep along with the changes in brain waves. Sleep efficiency, which means the duration for which we sleep when we are in bed decreases to about 80%.

The amounts of stage 1 and stage 2 sleep increase, and similarly, the amounts of stage 3 and stage 4 sleep, which are the deep sleep stages decrease.

This decrease in deep sleep actually begins at around 20 years old. The time in our first REM period, which is 90 to 100 minutes in younger adults, also decreases.

Perceptions about Sleep

Another issue is the perception that older people have about their sleep. What is normal to one older person, may feel devastating and disturbing to another.

While one older person who sleeps only 6 hours a night might complain of trouble sleeping, another older person might adjust and have no complaints at all.

Many surveys have been conducted regarding sleep in older people. According to which, most of the older people report a decreased total sleep time, an increased number of awakenings experienced during the night, an increased number of sleeping medications taken, an increased daytime sleepiness, and as a result, an increased napping behavior.

Secondary Sleep Disturbances

Some of the sleep disturbances seen are secondary to particular conditions that are common in elderly, such as nocturia, diabetes, pulmonary disease, cardiovascular disease, osteoarthritis, rheumatoid arthritis, and menopause. Other disturbances are secondary to medications.

Other Changes

Other changes also occur in sleep. There may be an increase in autonomic activity, for example, heart rate or blood pressure. Older people may become more susceptible to the environment.

For instance, the older people may listen to more noises that will disturb their sleep. They may even experience changes in biological clock or circadian rhythms.