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The Facts About Sleep and Sleep Disorders

Sleep is a vital process for both our bodies and minds, but many disorders can disrupt it.

A woman lays in bed hugging her pillow trying to sleep.

We've all spent nights tossing and turning, unable to fall asleep or get back to sleep after awakening in the middle of the night. Our minds race, filled with thoughts of getting back to sleep or lingering on the tasks we need to do the next day. Then, when we finally get back to sleep, the alarm rings, jarring us out of bed. We drag ourselves to the shower, spend the day fatigued and find ourselves irritable and lacking focus. Sound familiar?

Nearly 32 percent of adults ages 18 years and older lack needed sleep, according to the Centers for Disease Control and Prevention (CDC). For high school students, the number rises to about 73 percent. That's a lot of sleep-deprived people going through their day as zombies.

How sleep affects the body

Why is sleep so important? Sleep replenishes the body. It helps support the immune and cardiovascular systems, and affects growth and stress hormones, appetite and breathing.

Studies indicate a chronic lack of sleep and irregular sleep patterns increase the risk for depression, diabetes, heart disease, hypertension (high blood pressure) and obesity. Sleep issues can also be a sign of other underlying conditions, such as certain neurological conditions, depression and bipolar disorder.

How sleep can go wrong: short-term obstacles

We often sacrifice sleep because we have so many demands on our time: work, school, family, chores, exercise, errands. These obstacles keep us from getting the sleep we need to feel rested. When we aren't rested, we don't function at our best. We don't think clearly, we lose focus and our reflexes slow. Even an hour or two less of sleep a night can make us function at a lower level than people who get adequate sleep. Lack of sleep impairs our ability to pay attention to detail, problem-solve and reason at a high level, making us less productive at work. Our moods change when we don't get adequate sleep, so lack of sleep can impact relationships.

Moreover, lack of sleep can cause us to drive drowsy. Drowsy driving jeopardizes the safety of everyone on the road. About 100,000 police-reported motor vehicle crashes occur each year because of drowsy driving, resulting in about 1,550 fatalities and 71,000 injuries, according to estimates from the National Highway Traffic Safety Administration. Experts believe those numbers actually may be higher because it's difficult to determine whether a person was drowsy at the time of a crash.

How sleep can go wrong: chronic sleep disorders

A few sleepless nights can soon turn into a chronic sleep disorder. Sleep disorders affect the quality, timing or duration of sleep. They also impact a person's ability to properly function while awake. More than 100 different sleeping disorders have been identified, but they can be classified into six major groups: circadian rhythm imbalance, hypersomnia, insomnia, parasomnias, sleep breathing disorders and sleep movement disorders.

Getting out of rhythm

We have an internal body clock that functions in a repeating rhythm, known as the circadian rhythm, which is connected to light exposure. Typically, adenosine, a substance in the brain, rises during the day while we're awake and peaks in the evening when it's time to go to sleep. While we sleep, the body breaks down adenosine. We also receive environmental cues, such as light and darkness, that help determine when we feel awake and drowsy. In response to darkness, the body releases a hormone called melatonin, which prepares the body for sleep and then keeps us asleep during the night.

Imbalances in the sleep-wake circadian rhythm can prevent us from falling asleep, wake us up during the night or prevent us from sleeping as long as we'd like. What causes the circadian sleep-wake cycle to get offbeat? Staying up late at night, jet lag, shift work or exposure to the blue-light wavelengths found in TVs and computers can throw off the sleep-wake circadian rhythm.

Too much of a good thing

Some people suffer from a chronic sleep disorder known as hypersomnia. With this condition, they require a lot of sleep or have excessive daytime sleepiness. Hypersomnia can be caused by a variety of underlying medical conditions, such as fibromyalgia, hypothyroidism (low thyroid function), obesity (particularly when it's associated with obstructive sleep apnea) and viral illnesses. It can also be caused by altered brain function. When healthcare providers can't find an underlying cause, they classify the condition as idiopathic hypersomnia.

Tossing and turning

When insomnia creeps in at bedtime, individuals affected by the disorder toss and turn and just can't fall asleep or stay asleep. As a result, they often suffer from excessive daytime sleepiness and impaired functioning throughout the day. Insomnia can result from adverse effects of medications (even chronic use of sleep medications), anxiety, depression, stress, substance abuse, alcohol consumption or an undetected medical condition.

Paranormal sleep

You've likely seen paranormal events, or unusual events that can't be explained, depicted in TV shows or movies. Similarly, parasomnias involve unusual events that occur during sleep: confusion upon awakening, binge eating when partially awake, nightmares, sleep paralysis (inability to move the body when falling asleep or waking up), sleep terrors and sleepwalking. Behaviors associated with parasomnias may be observed by others, but the people experiencing the behaviors may have no recollection of them.

Breathing and sleep

A variety of disorders, known as sleep breathing disorders, affect breathing during sleep. Snoring occurs during sleep when a person breathes and the airflow causes tissues to vibrate in the back of the throat. Light snoring may not disturb sleep. Heavy snoring, however, may disrupt the quality of sleep and also indicate a serious sleep breathing disorder, known as obstructive sleep apnea, in which people temporarily stop breathing during sleep. This pause in breathing deprives the body of oxygen, which increases the risk for serious health conditions such as diabetes, heart disease and stroke. Some people have a form of sleep apnea known as central sleep apnea. This sleep disorder results from a condition in the brain that causes breathing to slow and become shallow during sleep.

Moving during sleep

Sleep movement disorders cause movement before or during sleep, making it difficult for people to fall asleep, remain asleep or feel rested. Sleep movement disorders include:

  • Bruxism, the grinding or clenching of teeth during sleep, which can result from stress.
  • Periodic limb movements, or repetitive muscle movements that can't be controlled, commonly disrupt sleep and occur about every 30 seconds for up to an hour.
  • Restless legs syndrome, a neurologic condition described as burning or itching in the legs that causes an overwhelming urge to move them. This condition may worsen without treatment.
  • Sleep-related leg cramping, or sudden, intense pain in the leg or foot that occurs when a muscle contracts.

A variety of factors can rob us of sleep. The good news is that many of these sleep disorders can be prevented or managed by using best sleep practices.

Best sleep practices

What can you do to get a good night's sleep? Change your behaviors during the day and right before bedtime. Engage in physical activity during the day to help you fall asleep when it's time. Relax before bedtime—meditation, reading, soft music or a warm bath might help you to relax. Create a comfortable, dark, relaxing environment in your bedroom. Limit the use of your bed to sleep and sex. Leave electronic devices such as computers, smartphones and TVs behind.

Establish a good routine by going to bed at the same time every night and getting up at the same time every morning. This means no sleeping in on the weekends. Set your bed and wake times to ensure that you get at least seven hours of sleep. If you don't fall asleep after 20 minutes, get out of bed for a while and return to bed when you feel sleepy.

Avoid eating large meals and drinking beverages with alcohol or caffeine late in the day. If you get hungry at night, eat a healthy, light snack. Limit beverages before bedtime to avoid trips to the bathroom during the night.

If your sleep issues continue despite these practices, keep a diary of your sleep routine for about two weeks. Record such items as when you exercise, go to bed, go to sleep, wake up, take naps and drink alcohol or beverages containing caffeine. Then, visit your healthcare provider and share the diary at the visit. You should also mention any medications or supplements that you take because they may be making it more difficult to fall asleep.

Treatment options

Some sleep disorders require treatment beyond best sleep practices. If you experience sleep apnea or even think you have it, don't delay treatment from a healthcare provider because treatment reduces the risk for serious health-related conditions. Get a sleep test performed by a licensed physician trained in sleep medicine, often a neurologist. You also may benefit by sharing your sleep diary, use of medications, medical conditions and information about your sleep environment and job/lifestyle with the physician. Treatment for obstructive sleep apnea may include lifestyle changes such as reducing the use of alcohol or other sedatives, lying on your side to sleep and losing weight.

If these lifestyle changes aren't enough, your doctor may recommend the use of a continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BPAP) device to push air into your airway through a mask or nasal prongs while you sleep. If you're diagnosed with central sleep apnea, treatment will focus on the underlying cause, which may be a brain infection or heart failure. Some sleep movement disorders may require medications if lifestyle changes don't improve sleep.

Lack of sleep can be frustrating, but even serious sleep disorders can be managed. If you have difficulty sleeping, seek help from your doctor or a sleep specialist and start your journey to feeling rested again.