Sleep experts comment on diagnostic criteria for narcolepsy, factors that may lead to misdiagnosis, and the impact of the condition on a patient’s quality of life.
Richard K. Bogan, MD, FCCP, FAASM: We have a high prevalence of mood disturbance, anxiety, and depression in people with narcolepsy. They’re sleepy, and something happens to their neurons. Whether it’s cause and effect, we don’t know, but the prevalence of mood disturbance is fairly high—maybe as high as 35%. These individuals, therefore, are often treated with an SSRI [selective serotonin reuptake inhibitor]or an SNRI [serotonin-norepinephrine reuptake inhibitor], which are REM [rapid eye movement]–suppressing drugs. There’s some evidence that REM-suppressing drugs suppress our ability to be able to see REM sleep. Our nosology requires that patients have adequate sleep at night and that they fall asleep, less than 8 minutes on average. We see 2 sleep-onset REM episodes. At least 25% of the time, we get a false negative because of these factors.
Sleepiness often interferes with quality of life: executive function, speed of processing, divided tasks, and memory. Many of the patients with narcolepsy who come to me say, “I’m developing dementia because I can’t remember things.” Mood, motivation, workplace performance, and fatigue-related accidents are all big issues for these individuals. We use the Epworth Sleepiness Scale, and you use it in your clinic, to compare how sleepy these individuals are compared with the general population.
This is a clinical diagnosis, and we use 2 nosologies. We use the International Classification of Sleep Disorders III, but we also use the DSM-V [Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition], which tends to be more clinical. There are slightly different rules, but we have individuals who are sleepy and who have REM-dissociative symptoms. They have disruptive nocturnal sleep. When we do these diagnostic studies, we have an abnormal sleep latency test. Many of these patients come from psychiatrists because they’re treated for depression or attention deficit disorder. Sleepy patients have trouble with attention, focus…and mood. It has a huge impact on the quality of life of these individuals. Therefore, they want to be treated, because they have trouble getting to work, staying awake in class, or even relating to their families. Many mothers have told me that they feel bad their self-esteem is so bad, because they don’t have the motivation or the ability to stay awake and take care of their kids. There are huge impacts on quality of life.
Asim Roy, MD: Yes, huge. A number of patients we hear from were in their teens or younger when this all started. They’ve been told they’re lazy. You’re a teenager, you’re depressed, and all these other things come into the picture, and they get labeled. Sometimes many of these situations coexist with one another—they’re comorbid diseases—but sometimes it’s because they’re so sleepy that those other symptoms start creeping in: they can’t socialize as much, they can’t hang out with their friends, they can’t get their studies done, they have a hard time getting through exams. If you can’t get to them early, they can get through a big chunk of their young, formative years without a diagnosis and then have a lot of setbacks throughout their lives. It’s amazing how some of our patients in their 20s and 30s are working or went through grad school but had to kind of fight through all that. Then there are the ones who’ve lost 20 jobs by the time we see them because they can’t stay awake or make it to work properly. It’s important that we take these issues, especially in the teenage and college years, and identify these patients earlier. The average is 10 or 15 years from disease onset to time of diagnosis. That’s a very long time to live with something debilitating and no one has an answer for you.
Richard K. Bogan, MD, FCCP, FAASM: The prevalence of narcolepsy is about 1 in 2000. If a primary care practitioner has 2500 patients, he or she may have only 1 patient with narcolepsy in the practice, so it might be difficult for them to make the diagnosis. The delay in diagnosis in those individuals is very common. We have to be alert and think about disrupted sleep, the dream-related phenomena, and the profoundness of the sleepiness. We need to qualify how sleepy they are. It’s really important.
Transcript Edited for Clarity