Is narcolepsy lost in sleep apnea’s shadow? Some sleep specialists advocate for improved screening protocols and increased symptom awareness.

By Risa Kerslake, BSN-RN

Compared to other sleep disorders, narcolepsy remains less common, affecting 44.3 in 100,000 people in the United States. For context, the prevalence of obstructive sleep apnea (OSA) is 3,420 per 100,000.

Public interest in sleep health has increased, which gets people in the door for care, says Matthew Davis, MD, a neurologist-sleep specialist at Sleep Dynamics, a New Jersey-based sleep center. “But the problem,” he adds, “is there’s so much focus on sleep apnea that patients with narcolepsy get missed really easily.”

Narcolepsy Misconceptions

Many team members at sleep disorders centers say they have very few narcolepsy patients, “but I suspect this could be they’re not looking for them,” Davis says.

Narcolepsy’s rare occurrence can be defended in a 2000 study surveying sleep centers. Investigators found two-thirds of patients had sleep apnea diagnoses and referred to the other third as non-respiratory sleep disorders. About 5% had a narcolepsy diagnosis.

“This 5% benchmark was drilled into us. At the time, it was probably underestimated, and now it certainly is underestimated,” Davis says. With new therapeutic options and a greater recognition of narcolepsy, Davis says that 5% is likely higher. 

Another concern that can contribute to the so-called rarity of narcolepsy is its portrayal in popular media: the Hollywood version of people falling asleep while talking or standing up. 

“There is a cartoonish portrayal of cataplexy on TV and in movies in which any laughter or excitement causes abrupt falls or face-plants. More commonly, people with narcolepsy experience partial cataplexy, sagging of the face, weakness in the hands/arms, slurring of speech with a strong emotion. Full collapses with cataplexy occur with more variable frequency but get more attention when it happens,” says Kiran Maski, MD, MPH, a neurologist-sleep specialist at Boston Children’s Hospital. 

Focus on Sleep Apnea

A study found that up to 1 in 4 people with narcolepsy also have OSA.3 Having both conditions can make it more challenging to diagnose narcolepsy, says Maski, the paper’s first author. According to Maski, providers may focus on a diagnosis of OSA when patients complain of daytime sleepiness because it is a more common condition and miss the primary diagnosis of narcolepsy. 

Davis has sometimes treated patients for years for what he assumed was sleep apnea, even severe cases, but at some point he would realize that maybe he missed something.

Narcolepsy usually can’t be diagnosed solely on a polysomnogram. There are features, such as entering REM sleep quickly, that support a diagnosis of narcolepsy with cataplexy if classic symptoms are reported, but this scenario is uncommon, says Maski, also an associate professor of neurology at Harvard Medical School. 

Clinicians have to actively pursue narcolepsy with targeted questions about symptoms and order a multiple sleep latency test (MSLT), which can be prone to error if not done correctly. Age, mental state, habitual sleep schedules, shift work, and medications are factors that affect the reliability of the MSLT.4

Many patients don’t even get the testing that could enable a diagnosis of narcolepsy. People with narcolepsy may alert their primary care doctor to a sleep concern, and the doctor could then order a home sleep test, which only evaluates for sleep apnea. Or worse, it’s sleep specialists themselves who order home tests and find nothing significant. 

If home sleep tests are normal, the story often ends there, with patients being told they don’t have a sleep disorder, Davis says.

“That’s where we’re missing all these patients. No one thought to look for narcolepsy, even in sleep centers,” Davis says. “When I say we’re missing it, I don’t mean we’re missing it on the lab testing. I’m saying we’re not even ordering the lab testing.”

Overlooked Narcolepsy Symptoms

Explaining symptoms to clinicians can be especially challenging when people don’t have the correct terminology or can’t describe them in ways a clinician recognizes. These factors can bring patients down the wrong diagnosis path for years, trying different medications, says Monica Gow, co-founder and executive director of Wake Up Narcolepsy

“Prior to diagnosis, some people with narcolepsy may be in and out of sleep all day, and sometimes they don’t even know they’re sleeping,” Gow says. “During the diagnosis period, individuals may experience hallucinations, a symptom of narcolepsy, while either falling asleep or waking up. When they describe this symptom to their doctor on their journey to find a diagnosis, it can be interpreted as a symptom of psychiatric disorder.”  

“Even something like cataplexy in children—sometimes they just think they’re clumsy, or they lose their smile when they laugh. It just becomes part of their character as opposed to thinking this could be something external,” says Julie Flygare, JD, president and CEO of Project Sleep and a narcolepsy patient advocate and speaker.

While daytime sleepiness is ‌a chronic daily symptom, cataplexy can be more episodic and triggered by specific emotional experiences such as laughter, Maski says. Other core symptoms, such as sleep paralysis or hypnagogic hallucinations, have been reported by only 25% of people with narcolepsy at the time of diagnosis, she adds. “It might be something that’s occurred once or twice in the last months or years, and people don’t have a good recall of that event or weren’t clear what it was,” she says.

The symptoms of narcolepsy can also be subtle because sleepiness may mostly occur in passive situations that don’t require a lot of engagement, such as sitting in a meeting or classroom setting. In Maski’s experience, people with narcolepsy may not be aware of how much they are sleeping during daytime activities until it is pointed out to them by others.  

Also, daytime sleepiness is a common complaint among the general population for reasons like not getting enough sleep at night. “When a patient with narcolepsy comes in, it’s hard to recognize their presentation from a general background of sleepy children and teens,” Maski says.

Medical School Sleep Education

The underrecognition of narcolepsy can also be traced back to medical schools and training clinicians receive in sleep medicine—or lack thereof, according to Davis, who offers to talk to students at local medical schools about narcolepsy. 

When Flygare speaks at medical schools to share her story as a person with narcolepsy, it’s usually an hour-long luncheon. “I’ve just doubled their sleep education because they only spend one hour on sleep as it is,” she says.

General pediatricians have limited opportunities to learn about sleep health in their training, says Maski. Very few residencies include a sleep rotation. 

It’s why Maski and her team created the Pediatric Hypersomnolence Survey as a free tool meant for primary care providers seeing patients with severe daytime sleepiness so that symptoms of sleep paralysis, cataplexy, and severe daytime sleepiness could be identified early and triaged more appropriately to a sleep provider for further investigation.5

“Providers should learn to ask specific questions when a patient presents with complaints of daytime sleepiness. They should know how to counsel on common sleep problems and learn to screen for sleep disorders, like obstructive sleep apnea, but also narcolepsy,” Maski says. 

Patients usually don’t see sleep specialists initially. “There are stories of people’s narcolepsy being recognized first by one of their other doctors who put it all together, remembering they heard about this condition in medical school,” Davis says.

Flygare has a sports therapist to thank for getting her on the path to a diagnosis after discussing her knees buckling when she laughed. The sports therapist suggested she may have cataplexy. Flygare took the word home with her and learned it was a term related to narcolepsy. 

“I was like, ‘Narcolepsy? No, that’s not me. That’s a joke about someone falling asleep when they’re standing,’” says Flygare. Later, Flygare thanked the sports therapist. “I told her, ‘You changed my life…other doctors have missed this,’” she says. 

Next Steps

The bottom line, says Davis, is if patients are complaining of sleepiness and other symptoms, with or without a sleep apnea diagnosis, don’t end the story there.

“It’s important to be open-minded, to really analyze the symptoms,” Gow says. She spoke with a person with narcolepsy who didn’t receive an accurate diagnosis for 40 years. “The sleep doctor who finally diagnosed her, she said he took her concerns seriously, that all the questions he asked her were like he knew her all those years.”

It’s a long journey, adds Flygare. Physicians need to think of themselves as team members on this journey and help their patients think about next steps and who else needs to be a part of that team.

“We use the statistic of eight to 15 years of a delay to diagnosis,” says Flygare, “Putting it in a specific context, this means all of someone’s high school memories, all their college memories, are clouded by this condition. People wait months to get a sleep study. That can be an entire semester, someone driving to and from school when they’re in college and not being able to stay awake. That’s a huge dent in someone’s life.”

References

1. Acquavella J, Mehra R, Bron M, et al. Prevalence of narcolepsy and other sleep disorders and frequency of diagnostic tests from 2013-2016 in insured patients actively seeking care. J Clin Sleep Med. 2020 Aug 15;16(8):1255-63.

2. Punjabi NM, Welch D, Strohl K. Sleep disorders in regional sleep centers: a national cooperative study. Coleman II Study Investigators. Sleep. 2000 Jun 15;23(4):471-80.

3. KP Maski, E Steinhart, D Williams, et al. 0671 Listening to the patient voice in narcolepsy: Diagnostic delay, disease burden and treatment efficacy. Sleep. 2017 Apr;40(28; suppl 1):A248.

4. Trotti LM. Twice is nice? Test-retest reliability of the Multiple Sleep Latency Test in the central disorders of hypersomnolence. J Clin Sleep Med. 2020 Dec 17;16(S1):17-8.

5. Maski K, Worhach J, Steinhart E, et al. Development and validation of the Pediatric Hypersomnolence Survey. Neurology. 2022 May 10;98(19):e1964-75.

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