Suffering from Insomnia?
Poor sleep quality can occur as a result of stress, the inability to "switch off" or major depression. Poor sleep quality is caused by the individual not reaching stage 4 or deep sleep which has restorative qualities. There are, however, people who are unable to achieve stage 4 sleep due to brain damage that still lead perfectly normal lives.
Irregular sleep patterns affect up to half of all older people. In Britain about 1.5 million people regularly use sleeping pills, with older people making up about 40 per cent of these.
Lack of sleep - or even sleeping at the wrong time - really affects our health and quality of life. We feel tired and irritable, and find it hard to concentrate and make decisions. Lack of sleep can damage the immune system and accelerate conditions like high blood pressure and diabetes. Sleeping at the wrong time can be just as problematic. Some older people find they can sleep in the daytime but less so at night, which is not only unnatural but inconvenient.
The five stages of sleep
- When you close your eyes, your body temperature drops and brainwaves become slower. You start to nod off, falling into a light sleep when stress hormones start to drop.
- You've lost consciousness, your digestion slows down and functions like hearing are put on standby.
- The first phase of deep sleep, which usually occurs within 15 minutes of falling asleep. Your muscles relax, your blood pressure and heart rate fall and your brain produces slow waves.
- The deepest sleep of all, which lasts for about two to three hours.
The above four levels of sleep may play a vital role in energy conservation, growth, tissue repair and information processing. Growth hormone, for instance, is produced during stages three and four.
Our final stage of sleep is dream sleep, characterised by rapid eye movements (REM), much brain activity and rising blood pressure. Adults average two to three hours of REM sleep a night, mostly towards morning. REM sleep is also vital to our well-being, probably because dreams are a spring cleaning for the mind.
It is also known that we have a natural sleep rhythm of around 25 hours, which is brought into line with the 24 hour day by the effects of light. Light falling on the retina stimulates the production of melatonin, which keeps our body clock in time.
We also have two periods of sleep-readiness - between 2pm and 6pm and 2am and 6am.
Sleep patterns do, however, change as we age. As we get older we get less of stages three and four sleep. After the age of 60, we get very little deep sleep, possibly because we do not need it. Older people tend to sleep and to wake earlier, and to get more broken sleep, often because of the vital trip to the loo, or because of other health problems, such as arthritic pain. REM sleep stays constant through adult life.
