After more than four decades studying and treating sleep disorders, Thomas Roth, PhD, has seen virtually every slumber-related malady—from mild to severe. Consumers are more aware than ever about the dangers of obstructive sleep apnea (OSA), and the medical community has spent considerable money and brainpower to better understand OSA.
Narcolepsy, on the other hand, has occasionally taken a back seat, and Roth, director of the Sleep Disorders and Research Center at Henry Ford Hospital in Detroit, believes that must change. “I want patients with narcolepsy to be diagnosed early,” says Roth, a former chairman of the World Health Organization’s Worldwide Project on Sleep and Health. “The earlier you diagnose, the less long acting the consequences are.”
Researchers know that narcolepsy is an abnormality of certain systems in the brain, and Roth says there is also a belief that it is an autoimmune disease. Determining the exact pathophysiology is the next challenge that “could ultimately lead to newer and better therapies.”
Roth is quick to point out that there is not just one type of narcolepsy. Instead, there is essentially narcolepsy with cataplexy (a condition described as a transient loss of muscle tone that affects roughly 70% of narcoleptics) and narcolepsy without cataplexy. “I suspect in the next 5 to 10 years we are going to develop a spectrum of different narcolepsy phenotypes, and the genetic associations with those,” says Roth, who also serves as a professor in the Department of Psychiatry at Detroit-based Wayne State University School of Medicine.
When that happens, it could lead to faster and more accurate diagnoses because clinicians will be more aware of the different phenotypes. “That will lead to better treatments,” says Roth, “some of which may involve orexin, a transmitter in the brain which is deficient in patients with cataplexy.”
From the Beginning
After the identification of rapid eye movement (REM) sleep in the mid 1950s, the world of slumber opened up to serious discussion. Roth entered the field in 1970, but he estimates that “sleep disorders medicine” as a field was not formally organized until 1975.
Narcolepsy diagnosis has progressed since those early days, but there is much work to be done. In an effort to identify narcolepsy in a more efficient and accurate manner, Roth has collaborated with Jazz Pharmaceuticals in a program called Narcolepsy Link.
The idea behind Narcolepsy Link is to increase awareness in the medical community, and among patients, about how to recognize, identify, and accurately diagnose narcolepsy. “Dr. Schwartz [Jonathan R. L. Schwartz, MD] and I did a webcast several weeks ago, and we are going to do another one,” says Roth. “The whole idea is to make sure it does not take 10 years for some people to get diagnosed. Narcolepsy Link is a multi-faceted program aimed at primary care physicians, neurologists, and sleep specialists.”
Among patients, a misconception exists that narcoleptics are so sleepy that they fall asleep while talking. “While that degree of sleepiness is possible,” says Schwartz, “most narcoleptics don’t fall asleep while actively engaged in talking with someone, but some do have sleep attacks in more sedentary or monotonous situations.”
Rounding Out a Complete Program
Roth concedes that narcolepsy is not necessarily a “money maker” for the modern sleep center—at least not yet. Instead, sound narcolepsy diagnosis and care are necessary to round out a complete sleep program that addresses all facets of sleep disorders.
Much like sleep apnea, the potential patient population is massive. “About 50% of narcoleptic patients remain undiagnosed,” confirms Roth. “One of the reasons is that it takes a long time before patients get to the right doctor. It’s estimated to be 10 years on average, and it used to be much longer than that.”
Why so long? Too often, patients and clinicians alike dismissed narcolepsy as “too rare” and “something they did not have to know about.” Part of that mindset comes down to the nature of the symptoms. “The number one symptom is excessive daytime sleepiness,” says Roth. “Patients don’t talk about that. They talk about being tired and fatigued.”
The result, says Roth, is that most people get misdiagnosed with things such as depression. “They go to a doctor and talk about being tired, and physicians should be asking about snoring and/or cataplexy, but by and large they ask about depression,” he says. “Sleep disorders generally are not top of mind for most clinicians and narcolepsy is even less top of mind.”
“Many non-sleep specialists, including primary care physicians (PCPs), think of narcolepsy as a rare condition and hence may not consider it in a differential diagnosis of sleepiness,” adds Schwartz, a sleep specialist and medical director of Integris Sleep Disorders Center of Oklahoma. “Patients tell their PCPs ‘I’m tired’… instead of I’m sleepy instead of saying ‘I’m sleepy’ or ‘I can’t stay awake during the day.’ Many times these phrases lead PCPs to consider depression and other conditions as the cause of these symptoms. While sleep specialists are familiar with narcolepsy, not all physicians that practice sleep medicine evaluate for or treat narcolepsy.”
Narcolepsy Link is designed to get doctors to think out of the “depression box” and carefully explore the realm of sleep disorders. PCPs are especially prone to over-focus on depression, but sleep specialists can make the same mistake. “Sleep specialists focus on sleep apnea,” he says. “Apnea is prevalent, but narcolepsy can be a major cause of daytime sleepiness, and it has to be part of the differential diagnosis. You must ask questions about cataplexy, and you must understand what you’re looking for, which are what our educational initiatives are about. For example, how do you take a history of cataplexy? You need to know that.”
With increased awareness, Schwartz believes that PCPs will be more likely to ask more pointed questions “to rule out possible causes of sleepiness, which may include other sleep/wake disorders, medications and insufficient sleep.” The diagnostic evaluation for narcolepsy includes an overnight sleep study, followed by a daytime test called a Multiple Sleep Latency Test (MSLT).
As for a link between narcolepsy and sleep apnea, Roth says sleep apnea patients are more likely to be narcoleptics. However, he cautions that it’s a complex issue. “There is something called sleep apnea syndrome, which tends to afflict overweight males who are hypertensive,” says Roth. “Patients with narcolepsy don’t have that type of apnea. They have apnea indexes of 15 to 20, and they are not necessarily overweight.”
Through the webinars offered by Narcolepsy Link, Roth and Schwarz are covering questions that don’t often receive a lot of exposure, such as: If you have somebody with narcolepsy and apnea, which do you treat first? How do you compare the severity of narcolepsy to the severity of apnea, and how do you proceed? “Ultimately, we must expand our education to include this type of information,” concludes Roth.
About Thomas Roth, PhD
Thomas Roth, PhD, is the director of the Sleep Disorders and Research Center at Henry Ford Hospital in Detroit, a professor in the Department of Psychiatry at Detroit-based Wayne State University School of Medicine, and a clinical professor in the Department of Psychiatry at the University of Michigan College of Medicine in Ann Arbor.
After serving as president of the Sleep Research Society and the founding president of the National Sleep Foundation (NSF), Roth became chairman of the National Center on Sleep Disorders Research advisory board. In addition, he was a member of the board of directors of the Associated Professional Sleep Societies LLC (APSS), chaired the APSS Program Committee, and the governing board of the World Sleep Federation. Roth was instrumental in forming the Association of Sleep Disorders Centers (ASDC), now the AASM, and served as the organization’s second president. He is also the former chairman of the World Health Organization’s worldwide project on sleep and health.
About Jonathan R. L. Schwartz, MD
Jonathan R. L. Schwartz, MD is a clinical professor of Medicine at the University of Oklahoma Health Sciences Center. He also is the medical director of the Integris Sleep Disorders Center of Oklahoma, Oklahoma City. Schwartz earned his degree in medicine from Oklahoma University Medical School and Health Sciences Center, where he also completed an internship and residency in internal medicine, as well as a fellowship in pulmonary disease and critical care medicine. He is board certified in sleep disorders medicine, internal medicine, and pulmonary disease. Schwartz has served as an investigator in numerous research projects involving narcolepsy, obstructive sleep apnea, insomnia, shift work sleep disorder, and restless leg syndrome, and authored a number of articles regarding sleep disorders and their therapy.
Thomas Roth, PhD