Sleep Disorders
Sleep an Overview
| States and Stages |
| Types of sleep disorders |
| Causes |
| Management |
| Myths & Realities |
Introduction
The very word "sleep" makes one feel relaxed cozy and comfortable. But how many of us are aware of the mysterious importance of sleep? A regular, adequate and restful sleep is as important for your physical well-being as getting enough food and exercise.
Until just a few years ago, sleep was perhaps the most misunderstood function of the human body. In earlier times, sleep was considered a passive phenomenon during which major elements of the brain rested. After years of subsequent research, sleep experts found that lot more things happen during sleep than people are aware of. The sleeping brain is more active at various times of the night than it ever is during the day.
"Sleeplessness" at first glance may not seem like a serious health problem, but not getting enough sleep can affect every htmect of our lives. If you have trouble getting to sleep or sleeping through the night, if you wake up too early or if you feel very tired during the day, you may be having some sleep problems. When sleep is poor, people may experience fatigue, a loss of energy and/or a loss interest. People may have problems with memory and feel ill , sleepy, or less than perfect. Poor sleep can cause loss of work time and may make medical and mental conditions worse. It is therefore important to take sleep seriously and to carefully sort out the causes of sleep disorders.
A word of caution, please do not attempt any self-diagnosis and/or self-medication for sleep disorders. The earlier the professional help is sought, the faster will be the recovery.
Although one third of our lives is spent in "sleeping" yet many of us are not aware that there are two kinds of sleep:
- Rapid eye-movement (REM) sleep
- Non-rapid eye movement (NREM) sleep
During REM sleep, although the eyes are closed, the eyeballs are engaged in rapid movement. Scientists have identified certain neurons in the human brain that directly affect REM sleep. About 80-90 percent of the time people awakened during or immediately after REM sleep, report that they were dreaming. REM sleep is also termed as 'dream sleep'.
The NREM sleep has four stages of depth
Stage 1 (light sleep) occurs in between wakefulness and light sleep. In this stage the
body readies itself for sleep. This stages lasts between 10 and 15 minutes.
Stage 2 (so-called true sleep). We are in this stage for 50% of the time each night.
In this stage blood pressure falls and heart rate decreases.
Stage 3 and 4 are collectively known as deep sleep and are characterized by slow brain activity.
In this stage the mind and body repairs itself. These stages are very important for
maintaining a persons health.
REM sleep first occurs about 90 minutes after falling asleep and then about 3-5 times each night. The first cycle lasts for 15-20 minutes and the last cycle for 30 to 60 minutes. During REM sleep muscle tone is greatly reduced, but brain waves show the same active frequency as when person is awake. This is the dreaming phase of sleep, necessary for long-term emotional well-being. REM sleep may play a role in increasing memory and the learning process.
Organization of human sleep: Normal nocturnal sleep in adults displays a consistent organization from night to night. After sleep onset, sleep usually progresses through NREM stage 1 to 4 within 45 to 60 min. Slow wave sleep predominates in the first third of the night and comprises 15 to 25 percent of total nocturnal sleep time in young adults. The percentage of slow wave sleep is influenced by several factors, most notably age. Prior sleep deprivation increases both the rapidity of slow wave onset and its percentage of total sleep.
After the first slow wave sleep episode, the progression of NREM stages reverses. The first REM sleep occurs usually not less than 80 min. after sleep begins, although REM latency shortens with advancing age. More rapid onset of REM sleep in a young adult may (particularly if less than 30 min.) suggest pathology such as endogenous depression, narcolepsy, circadian rhythm disorders, or drug withdrawal.
NREM and REM alternate through the night with an average cycle of 90 to 110 min. ('the ultradian' cycle). As the sleep period lengthens, the portion of each cycle composed of slow wave sleep decreases and that of REM sleep increases. Overall REM sleep is 20 to 25 percent of total sleep, while NREM stages (1and2) constitute 50 to 60 percent (increasing in elderly subjects).
Different Types Of Sleep Disorders :
The commonly seen sleep disorders include
Insomnia - is inability to sleep or unable to get enough sleep.
Narcolepsy - characterized by excessive sleep.
Sleep Apnea - characterized by brief interruption of breathing during sleep
Circadian Rhythm Sleep Disorder - characteristics include difficulty in falling asleep or waking at the desired time, difficulty in staying awake in the evening or waking too early in the morning and trouble in getting enough sleep during available sleep times.
Restless Leg Syndrome(RLS) and Periodic Limb Movement Disorder (PLMS) - generally occurs in the elderly. RLS is characterized by unpleasant feelings in the feet or legs. PLMS is indicated by repeated jerking or twitching motions of the legs and less frequently the arms.
Insomnia: Insomnia is not a disease but common, usually temporary, sense of not having had enough sleep to feel refreshed; it may be experienced as an inability to sleep despite being tired, or as a light, fitful sleep that leaves one fatigued upon awakening.
Insomnia affects 20% population at any given time. The incidence and prevalence of insomnia increases with age.
Insomnia is 1.5 times more prevalent in adults over 65 years of age than in adults less than 65 years.
Women are 1.3 times more likely to report insomnia than men.
Insomnia characterized depending on the duration as
Short term Insomnia - refers to periods of sleep difficulty lasting between one day to few weeks. It generally occurs in people who are temporarily experiencing either stress or environmental change, jet lag, side effects of medication or change in life style.
Long term Insomnia - refers to poor sleep that occurs for at least three nights per week and lasts for more than 3 weeks. It is more complex and often results from a combination of factors, including underlying physical or mental disorders. Depression is one of the most common causes of chronic insomnia. Other causes could include arthritis, kidney disease, heart disease, asthma, Parkinson's disease, sleep apnea, restless leg syndrome, hypothyroidism etc.
Sleep deprivation has several negative effects on performance, as well as physical and mental health. Some of the major causes of sleep problems are:
Physical Factors - Disorders of breathing or periodic muscle contractions during sleep can cause disturbance in sleep. Other medical problems which could be the cause are allergies, arthritis, heart disease, hypertension, asthma, rheumatologic conditions, hyperthyroidism, Parkinson's disease, Alzheimer's disease. Also headache, menstruation and hot flashes could upset sleep.
Psychological Factors - Stress, depression and anxiety are some of the common psychological factors affecting sleep. More than 70% of people with depression complain of insomnia. Environments not conducive to sleeping, concern about problems such as family illness or an unrewarding job can interfere with sleep. Last but not the least , if people are worried about their ability to sleep, their concern may actually keep them awake.
Lifestyle Factors - Varying bedtimes frequently and change of work shifts are some of the lifestyle factors that can affect sleep. Drinking coffee or caffeine containing beverages and smoking as well as alcohol intake close to bedtime also results in poor sleep. Many "drugs" and medication can worsen sleep problems.
Environmental Factors - Too much light in the room and extremes in room temperature can also interfere with sleep. Noise pollution such as moving road traffic, airplane noise, or even neighborhood disturbances can disturb sleep.
As sleep is vital to our health and well being, we must not cut ourselves short from the amount of sleep that we get or suffer from sleep problems. Take control of your sleep problems before it takes control of you. Effective management of sleep problems begins with a visit to your doctor. Early assessment and action can prevent short-term sleep problems from developing into a chronic one. Your doctor is the best person to determine the cause of your sleep complaint and recommend the best course of action.
To prevent or relieve sleep problems and safeguard sleep making it more restful and pleasurable, it helps to practice good sleep hygiene. "Sleep hygiene" is a term used to describe techniques that promote good sleep
- Use a regular sleep/wake schedule
- Avoid naps especially in the evenings
- Increase exercise and aerobic fitness
- Do not exercise close to bed time, it may increase alertness
- Avoid intake of caffeine and alcohol just before sleeping
- A heavy meal just before bed time should also be avoided
- Try a light bedtime snack if hungry
- Schedule reasonable day time work hours
- Try to relax in the half an hour before bedtime. Reading meditation or taking a leisurely walk may help
- Try to keep yourself busy during the day to avoid excessive day time boredom
Trying behavioral techniques such as relaxation therapy, sleep restriction therapy, reconditioning and bright light can also improve sleep.
Relaxation therapy : Certain specific and effective techniques can reduce or eliminate anxiety and body tension. It usually takes much practice to learn these techniques and to achieve effective relaxation.
Sleep restriction: Some people suffering from insomnia spend a lot of time in bed trying to sleep. Such people may benefit from sleep restriction program that initially allows a only a few hours of sleep during the night. The time is then gradually increased until a more normal night's sleep is achieved.
Reconditioning: As a part of reconditioning process, the person is usually advised to go to bed only when sleepy. If unable to fall asleep, the person should get up and stay out of bed until sleepy and then return to bed. Throughout this process, the person is advised to avoid naps and wake up and go to bed at the same time each day. This will eventually condition the person's body to associate bed and bedtime with sleep.
Bright Light: If there is trouble in getting sleep early at night, it may help to wake up at the same time every morning to get as much bright light in the morning as possible. This will help to set the internal clock to an earlier time at night for sleep. If there is trouble staying awake in the evening and waking up early in the morning then bright light should be got in the evening. This will help to reset the internal clock to go to sleep later and wake up later.
(ALL VISITORS TO THIS SITE ARE CAUTIONED, NOT TO ATTEMPT ANY SELF-MEDICATION OR CHANGE OF MEDICINE/DOSAGE WITHOUT CONSULTING THEIR DOCTOR)
Some common myths about sleep:
Myth 1 : During sleep your body and brain shut down for rest and relaxation.
Fact : No
Although during sleep our body rests and restores its energy, sleep is an
active state. In fact the sleeping brain does a lot of work. The sleeping brain is more active
at various times at night than it ever during the day.
Myth 2 : Inspite of getting the usual night of sleep dozing unintentionally during
the day is normal.
Fact : No
The person who dozes unintentionally during the despite of getting the usual night
of sleep could be having some form of a sleep disorder. This needs proper treatment as untreated sleep disorder
can reduce productivity and increase the risk of several disorders.
Myth 3 : Worry is the primary cause of insomnia.
Fact : No
Insomnia can be due to various reasons including physical and mental conditions and stress.
Myth 4 : Insomnia affects only the elderly.
Fact : No
Insomnia affects people at all ages, usually for an occasional night or two.
But sometimes it can be for weeks months or even years.
Myth 5 : Our body has the ability to adjust to different sleep schedules.
Fact : No
The biological clock of the human body is programmed such that each person
feels sleepy during the nighttime and is active during the day time. This is the reason why people
who travel through multiple time zones have a 'jet lag' because they cannot maintain a
regular sleep-wake schedule.
Myth 6 : As people grow older they need less sleep.
Fact : No
It is not true that older people need less sleep but the ability to sleep
for a for long periods of time and get into the deep restful stages of sleep decreases with
age. Also older people could have medical conditions which contribute to sleep problems.
Myth 7 : Insomnia can be cured by itself.
Fact : No
Insomnia could be caused due to various reasons and requires proper attention
and treatment.
Myth 8 : People who drink alcohol regularly sleep better because alcohol
has a sedative effect
Fact : No
People who drink alcohol or in fact who abuse alcohol or drugs often suffer from insomnia
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