Sleep Disorder Facts

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How well did you sleep last night? Sleep disorders affect a person's ability to get a restful night's sleep. Examples include insomnia, restless leg syndrome, snoring and sleep apnea.


As many as 70 million Americans are afflicted with sleep-related problems. While some sleep disturbances may be linked to biological changes associated with aging or certain physical diseases, especially those that cause pain, others may be associated with a mental health disorder such as depression or anxiety.

Poor sleep may also stem from "bad" habits such as napping too long or too late in the day, or doing shift work which can really scramble your sleep cycles. On the other hand, you may simply not be giving yourself the opportunity to acquire ample shuteye.

Why Sleep is Important to Your Health

Disorders of sleeping and waking interfere with quality of life and personal health. Sleep is not just resting or taking a break from busy routines—it is essential to physical and emotional health. Adequate sleep may also play a role in helping the body recover from illness and injury. Inadequate sleep over a period of time is associated with obesity, diabetes, heart disease, and depression.

But the emotional and mental benefits of sleep are also significant. Even occasional sleeping problems can make daily life feel more stressful and less productive. And some people with chronic insomnia are more likely to develop psychiatric problems. Those who have trouble getting sleep may also experience problems in memory, learning, logical reasoning, and mathematical calculation.


Insomnia—the inability to fall asleep and remain there—affects many millions of people. Sleep apnea affects an additional 10 million to 15 million. Narcolepsy (falling asleep uncontrollably during the day) affects around 200,000. About 5% of the population has restless legs syndrome.

How Age Affects Sleep

While people of any age may be affected, there seems to be a large prevalence of sleep disturbances among older men and women. Sleep studies reveal that they get less REM (deep) sleep over time. With aging, sleep becomes more fragile; that is, it doesn't take much disturbance to awaken the individual. Women may first notice this during menopause.

How Much Sleep is Enough?

Most sleep experts believe you should get seven to eight hours of sleep a night. This figure varies considerably across the age span and from person to person. Still, if you're getting less than six hours of sleep per night regularly, you may be compromising your health and welfare.

If you have some of the following problems, you may need more sleep, or a better quality of sleep, than you are getting:

  • Tendency to be unreasonably irritable with co-workers, family, or friends
  • Difficulty concentrating or remembering facts.

When To Seek a Professional

If you're having chronic sleep difficulties, try practicing sensible sleep habits. If you've done all you can, however, and still aren't getting good, restorative sleep, talk with your family doctor. If you need additional help, ask for a referral to a sleep specialist. This may be needed, in particular, for more complex conditions such as narcolepsy. While this disease is not curable, it is treatable, though the regimen with carefully prescribed medications is complicated, and best handled by a sleep specialist. On the other hand, sleep apnea treatment can be very helpful.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Apr 29
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.

  1. Your Guide to Healthy Sleep. National Institutes of Health. National Heart, Lung, and Blood Institute.

  2. Sleep-Wake Cycle: Its Physiology and Impact on Health. National Sleep Foundation.