You may not think much about sleep until you’re not getting enough of it. Usually the first sign that your sleep quality is lacking is feeling excessively sleepy during the day.
Sleep disorders are a group of conditions that cause excessive sleepiness by disturbing sleep patterns and habits.
“It’s important to distinguish between fatigue and sleepiness,” says Northwestern Medicine Sleep Medicine Physician Sabra M. Abbott, MD, PhD. “Sleepiness means you have trouble staying awake doing daily activities. Fatigue is more feeling physically tired or lacking the energy to complete tasks, which may be indicative of another medical issue not directly related to sleep.”
Often sleepiness during the day can be caused by too little sleep, irregular sleep patterns or a disconnect between your body’s internal clock (circadian rhythm) and the 24-hour cycle of the world.
Here are some common sleep disorders.
It’s estimated that more than 18 million adults have sleep apnea in the U.S.
“Sleep apnea is the most common sleep disorder I see in the clinic,” says Dr. Abbott. “It involves frequent events where you’re not getting enough oxygen while you sleep, resulting in microarousals every couple of minutes.”
Sleep apnea prevents you from going into deep, continuous sleep. It’s typically a physical problem; something is obstructing your airway while you sleep. This includes many anatomical features, such as your tonsils and adenoids, the fat and musculature of your tongue, the muscles and fat around your airway, and your jaw structure.
Sleep apnea can be diagnosed with a sleep study, or with an easy home study kit that monitors your oxygen levels and breathing patterns during a night of sleep.
Sleep apnea can often be improved with positional therapy to make sure you’re sleeping in a position that minimizes airway obstruction, or with lifestyle modifications, like maintaining a healthy weight. Oral appliances can also improve sleep apnea. If these methods don’t work, your physician may recommend a continuous positive airway pressure (CPAP) device, which keeps your airway open during the night with a continuous stream of air delivered through a mask.
Roughly one in four adults in the U.S. develop insomnia. But, at least 75% of people with insomnia recover.
Insomnia is a sleep disorder that snowballs. It can start with something simple, like too much caffeine intake or as a side effect of a medication. It can be related to your circadian rhythm being misaligned with the 24-hour cycle of a typical day, or it can be related to stress and mental health. The initial underlying cause can lead to a negative association between your bed and your sense of sleep.
“With insomnia, there’s typically a predisposition, a precipitating factor, like anxiety or stress causing a bad night’s sleep, and then perpetuating factors, where you’ve conditioned yourself to think negatively about your bed because you spend more time awake in it than asleep,” says Dr. Abbott. “These people also typically can’t nap well; they’re stuck in a hyper-alert state.”
Often people with insomnia will adopt strategies for sleep that they presume to be helpful but are actually harmful, like spending more time in bed.
Insomnia treatment with the best long-term efficacy is cognitive behavioral therapy, which may include strategies like sleep restriction, where you spend less time in bed in general; this may lead to more time actually sleeping in bed. Incorporating other sleep hygiene strategies, such as limiting screen time and allotting appropriate time to wind down before bed, can also help with insomnia.
Narcolepsy is less common than sleep apnea and insomnia, affecting roughly one in 2,000 people. It’s typically diagnosed between the ages of 10 and 20. It causes you to feel overwhelmingly sleepy, and in some instances can cause uncontrollable sleep. Narcolepsy can present with or without cataplexy, or sudden loss of muscle tone while you’re awake.
While the cause of narcolepsy is unknown, many people who have narcolepsy with cataplexy have low levels of hypocretin in their brains. Hypocretin is the neurotransmitter that controls sleep-wake states and hunger cues.
Treatment for narcolepsy is highly individualized, and may involve medications or lifestyle modifications.
“Some medications provide great hope for people with narcolepsy,” adds Dr. Abbott.
Shift Work Disorders
Shift work disorders are disturbances in sleep cycles typically caused by working a night shift, or rotating shifts.
“In treating people with shift work disorders, the underlying theme is to help them adjust their lifestyle so that they’re maintaining the same circadian rhythm, which happens to be the opposite of most people’s,” says Dr. Abbott. “Consistency and light timing are key.”
If you work the night shift, you can combat excessive sleepiness by fully inverting your sleep schedule and minimizing your exposure to the brain-stimulating blue light of the morning by wearing blue light-blocking glasses on your way home from work.
Talk to your physician about scheduled napping, and try to keep your sleep schedule consistent, even on your days off.
Sleep-Related Movement Disorders
Periodic limb movements are characterized by the rhythmic flexion of your legs. “It’s a slow, alternate kicking movement in the legs that can be triggered by many things, including stress and medications,” says Dr. Abbott. “It affects the quality of your sleep.”
Parasomnia disorders include non-REM disorders, like sleepwalking, and REM disorders like REM behavior disorder, where your body doesn’t experience loss of muscle tone during REM, causing you to act out your dreams.
“It’s important to figure out the underlying cause of sleep movement disorders, which can range from medications to neurological disorders,” says Dr. Abbott. “If you’re experiencing a sleep-related movement disorder, consult your primary care physician to make sure these behaviors aren’t related to a non-sleep disorder.”
It’s also important to take appropriate safety measures for sleep-related movement disorders, such as making sure you’re sleeping in a safe environment and that your sleep partner is safe.
“Good sleep means good overall health,” concludes Dr. Abbott. “If anything is affecting your sleep, talk to your physician about it.”