Sleep Disorders

Welcome back to another episode of AudioBoards. Today, we're diving into the common sleep disorders.

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Transcript

Welcome back to another episode of AudioBoards. Today, we're diving into the common sleep disorders. Let's start with the basics—what are the primary states of sleep?

Sleep consists of two main states: REM sleep, or rapid eye movement sleep—also called dream sleep or paradoxical sleep—and non-REM sleep, which is further divided into four stages. Stages 3 and 4 are what we call "delta sleep."

Interesting! Now, how does REM sleep progress throughout the night?

The first REM period happens about 80–120 minutes after falling asleep and lasts around 10 minutes. Later REM periods are longer and mainly occur in the last few hours of sleep. On the other hand, most stage 4 sleep happens in the first few hours.

And how does aging affect sleep patterns?

As we age, we experience a decrease in stage 3 and 4 sleep, meaning we get less deep sleep. Instead, there’s an increase in wakeful periods, which is why older adults often struggle with staying asleep.

Speaking of sleep difficulties, let’s talk about insomnia. What are some key characteristics?

Insomnia includes difficulty falling asleep, staying asleep, waking up frequently at night, or waking up too early. Several factors contribute, such as stress, caffeine, physical discomfort, daytime naps, and even early bedtimes.

And depression can also play a role in sleep disturbances, right?

Absolutely. Depression is often associated with fragmented sleep, decreased total sleep time, and earlier REM onset. Interestingly, REM sleep deprivation has been shown to improve some depressive symptoms.

What about substance use—how does that impact sleep?

Alcohol, for instance, is often used as a sleep aid, but it actually disrupts normal sleep cycles. While it initially reduces sleep latency, it suppresses REM sleep early in the night, leading to REM rebound later. Chronic alcohol use increases stage 1 sleep and decreases REM sleep. Similarly, heavy smoking, caffeine, and stimulant use can cause difficulty falling and staying asleep.

And what about medications? Do they help or hurt sleep quality?

Some sedative-hypnotics like benzodiazepines and nonbenzodiazepines can improve sleep duration and reduce awakenings, but they come with risks. Withdrawal can lead to rebound insomnia. Antidepressants can also decrease REM sleep, and certain ones have a marked REM rebound when discontinued.

So, let's dive into the treatment options for insomnia. We’ve got two main approaches—psychological and pharmacologic. Let’s start with psychological methods.

Right, and psychological treatments primarily focus on improving sleep hygiene and using cognitive behavioral therapy, or CBT, which is actually considered the gold standard for treating chronic insomnia.

And let’s not forget about consistency! Waking up at the same time every day, even on weekends, is crucial for resetting the body's internal clock. Plus, avoiding alcohol and excessive fluids before bed can reduce nighttime awakenings. And for people struggling with stress-induced insomnia, relaxation techniques like meditation, deep breathing, or progressive muscle relaxation can be game-changers.

Now, if those methods don’t work or if the insomnia is severe, that’s when doctors may turn to pharmacologic treatments. The most commonly prescribed medications are benzodiazepines like lorazepam and temazepam, which help people fall asleep faster and stay asleep longer. But they do come with some risks—dependence, tolerance, and even memory impairment if used long-term.

Yeah, that’s why non-benzodiazepine hypnotics, such as zolpidem, zaleplon, and eszopiclone are preferred. These have similar sleep-promoting effects but may have a lower risk of dependency and next-day drowsiness.

Another option is trazodone, an atypical antidepressant that’s commonly prescribed at low doses for sleep. It’s effective, non-habit forming, but it does have some rare side effects like priapism in men.

And then there’s doxepin, a tricyclic antidepressant that can be used long-term without causing tolerance. It’s great for people who need something safe and effective over time.

Now, melatonin is another interesting option. It’s a natural hormone that helps regulate sleep-wake cycles. It’s most effective for things like jet lag or shift work sleep disorders rather than chronic insomnia, though.

That’s a good point! And there’s also ramelteon, which is a melatonin receptor agonist, it help with sleep onset but doesn’t carry the risk of dependency.

More recently, we’ve seen the introduction of dual orexin receptor antagonists (DORAs) like suvorexant and lemborexant. These work differently by blocking the wakefulness-promoting system rather than sedating the brain.

But DORAs aren’t perfect. Some studies suggest they might increase depressive symptoms in certain individuals, so they might not be the best choice for people with a history of depression.

Right, and of course, there are older options like antihistamines—diphenhydramine and hydroxyzine—which can be useful, but they have drawbacks like next-day grogginess and confusion in older adults.

The key takeaway here is that medication should be a short-term solution—typically one to two weeks—and always combined with behavioral strategies. Relying too much on sleep medications can create a cycle of dependence, withdrawal effects, and even rebound insomnia when stopping them.

So now, let’s talk about narcolepsy. It’s a neurological disorder that disrupts the brain’s ability to regulate sleep-wake cycles. People with narcolepsy can have sudden, uncontrollable episodes of sleep, even in the middle of an activity.

It often begins between the ages of 15 and 25, though it can sometimes take years before a proper diagnosis is made.

Right! It’s caused by the loss or dysfunction of orexin or hypocretin neurons in the lateral hypothalamus. Orexin is a neurotransmitter that plays a key role in keeping us awake and alert. When these neurons are lost, the brain struggles to maintain stable wakefulness.

And about 85–95% of people with narcolepsy with cataplexy test positive for the HLA DQB1 haplotype, a genetic marker associated with the condition.

Let’s break down the core symptoms. It involves excessive daytime sleepiness—that’s the main one. People experience irresistible sleep attacks multiple times a week, sometimes even daily. It’s usually accompanied by at least one of the following:

Cataplexy – This is a sudden loss of muscle tone, often triggered by strong emotions like laughter, surprise, or anger. Some people experience slight muscle weakness, like their knees buckling, while others may collapse entirely but remain conscious. It’s often confused with seizures!

Sleep paralysis – This terrifying phenomenon happens when a person wakes up but can’t move or speak for a few seconds or minutes. It occurs because the brain is still in REM sleep, but the body hasn’t caught up yet.

Hypnagogic or hypnopompic hallucinations – These are vivid, often dream-like hallucinations that occur while falling asleep (hypnagogic) or waking up (hypnopompic). They can be extremely realistic and sometimes scary.

You’d think people with narcolepsy sleep a lot, but their nighttime sleep is actually poor and fragmented due to frequent awakenings. Some people continue activities, like writing or driving, while in a sleep state but later have no memory of it.

Yeah, and one of the strangest aspects of narcolepsy is that people can jump straight into REM sleep, rather than cycling through the normal sleep stages. That’s why their dreams can feel so intense and immediate.

Diagnosis usually involves a polysomnogram - an overnight sleep study that monitors brain activity, eye movement, heart rate, and breathing. And a multiple sleep latency test, done the next day, measures how quickly someone falls asleep in multiple naps—and if they enter REM sleep too quickly, it’s a key sign of narcolepsy.

Another diagnostic tool is a cerebrospinal fluid test to measure orexin levels. In people with narcolepsy type 1 (with cataplexy), orexin levels are often low or absent.

Now, let’s talk about treatment. There’s no cure for narcolepsy, but symptoms can be managed with a combination of lifestyle adjustments and medications. The first line of treatment usually involves stimulant medications to help people stay awake during the day. Modafinil, armodafinil are the most common. Dextroamphetamine and methylphenidate are also used for severe cases, but they come with a higher risk of side effects like jitteriness, anxiety, and potential addiction.

Sodium oxybate is a powerful medication that improves nighttime sleep and dramatically reduces cataplexy. Tricyclic antidepressants like imipramine and clomipramine can help with cataplexy, sleep paralysis, and hallucinations by suppressing REM sleep. Selective serotonin-norepinephrine reuptake inhibitors like venlafaxine and fluoxetine are also used. 

Medications alone aren’t enough—behavioral strategies are key. People with narcolepsy should: Stick to a consistent sleep schedule, going to bed and waking up at the same time every day. Take short, scheduled naps throughout the day to reduce sudden sleep attacks. Avoid alcohol, caffeine, and heavy meals close to bedtime. Get regular exercise to improve sleep quality.

And let’s not forget the importance of work and driving accommodations. Narcolepsy can make certain jobs dangerous, so people may need flexible schedules or restrictions on driving.

"Now, let’s talk about Periodic Limb Movement Disorder, or PLMD. This is a condition where a person experiences involuntary lower leg movements, but only during sleep. It might sound harmless, but these movements can significantly disrupt sleep quality.

"Exactly. And because sleep is so fragmented, people with PLMD often experience daytime sleepiness, anxiety, depression, and even cognitive impairment. This condition is sometimes confused with Restless Leg Syndrome, but the key difference is that in Restless Leg Syndrome, the movements happen while awake as well."

And speaking of disrupted sleep, there’s another condition that affects millions of people worldwide—Shift Work Sleep Disorder. This occurs when someone’s work schedule forces them to be awake during the night and sleep during the day, which goes against the body's natural circadian rhythm.

Right. People with this disorder often experience excessive fatigue, difficulty concentrating, mood changes, and even long-term health risks like cardiovascular disease and metabolic issues. And managing these conditions requires a combination of strategies—good sleep hygiene, timed light exposure, and sometimes even medication.

Alright, Now what about lesser-known conditions like Kleine-Levin syndrome or REM sleep behavior disorder?

Kleine-Levin syndrome is rare and characterized by episodes of excessive sleep, hyperphagia, and hypersexuality. REM sleep behavior disorder involves acting out vivid dreams, sometimes violently. 

Periodic limb movement disorder and REM sleep behavior disorder can be treated with clonazepam with variable results. There is no treatment for Kleine-Levin syndrome, although lithium can prevent recurrences in some.

Thanks for joining us today!

That’s all for today’s episode. Thanks for listening to AudioBoards. Stay tuned for more educational content in our next episode! The views and opinions expressed on the AudioBoards Podcast do not necessarily reflect those of our employers. This podcast is for educational purposes only and should not be used to diagnose or treat any medical conditions. It is not a substitute for professional medical advice. Always consult a qualified, board-certified healthcare provider for any medical concern.