Dr Ahmad Abefe Sanusi is a neurologist at the Al Qunfudah General Hospital in Saudi Arabia. In this interview with SADE OGUNTOLA, he explains why excessive daytime sleepiness and irregular sleep cycles can negatively affect one’s health and other issues. Excerpt:
WHAT is narcolepsy, and how does it affect the body?
Narcolepsy is a chronic sleep disorder that affects the brain’s ability to regulate the natural sleep-wake cycles of the body. Normal sleep is divided into two main types: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. A normal sleep cycle alternates between NREM sleep and REM sleep every 90 minutes, with REM sleep first occurring after about 90 minutes and repeating four to five times through the night. Individuals with narcolepsy often fall into REM sleep unusually fast, often within 15 minutes of falling asleep.
People with narcolepsy may suddenly fall asleep during the day at inappropriate times and places, feel persistently tired and low on energy, experience disrupted or fragmented nighttime sleep, have difficulty concentrating and have a depressed mood. Individuals with narcolepsy are at an increased risk for conditions like hypertension, depression, anxiety disorders, and attention-deficit/hyperactivity disorder (ADHD). If narcolepsy is left undiagnosed and untreated, it can substantially interfere with daily life, impair emotional well-being, and disrupt social interactions, thus impacting school, work, relationships, and social life.
What are the main symptoms of narcolepsy?
Narcolepsy usually begins in an adolescent, and symptoms typically begin to occur between the ages of 10 and 30, although narcolepsy can occur at any age. The symptoms of narcolepsy include excessive daytime sleepiness (EDS), defined as the overwhelming and irresistible urge to sleep during the day (often described as sleep attacks) and is usually the first symptom of narcolepsy; cataplexy (seen in narcolepsy type 1), which refers to sudden loss of muscle tone, often triggered by strong emotions such as laughter or anger; and sleep paralysis, which means temporary inability to move or speak when falling asleep or upon waking. Additionally, individuals may experience hypnagogic or hypnopompic hallucinations, which are vivid dreamlike sensations when falling asleep or upon waking, respectively. Such hallucinations may include seeing a person, animal or shape. Narcolepsy type 1 can be distinguished from narcolepsy type 2 by the presence of cataplexy or low orexin (hypocretin) in the cerebrospinal fluid (CSF).
Do you have data on the number of people affected by the condition in Nigeria and globally?
The overall prevalence of narcolepsy is estimated to be around 0.05 per cent of the general population, indicating approximately one in every 2,000 people worldwide, translating to about 3 million individuals globally. However, the actual prevalence of narcolepsy may be underreported and can be quite challenging because of lack of awareness, underrecognition and misdiagnosis.
In Nigeria, narcolepsy is considered an uncommon disorder. A hospital-based study reported a prevalence rate of 0.026 per cent, indicating that approximately 26 out of every 100,000 individuals are affected. Another study among final-year medical students found that 25.4 per cent of respondents reported narcolepsy as the most prevalent sleep disorder in their cohort.
What is the difference between narcolepsy and epilepsy?
Narcolepsy and epilepsy are two distinct neurological disorders, though they may sometimes be confused because both can cause sudden episodes that disrupt normal activity. Narcolepsy is a disorder of sleep regulation. Consciousness or awareness is not lost unless the person falls asleep. In contrast, epilepsy is a disorder of abnormal brain electrical activity defined by recurrent, unprovoked seizures. Consciousness or awareness is often impaired or lost in epilepsy, depending on the type. Furthermore, tests to confirm narcolepsy are totally different from those for the diagnosis of epilepsy.
What causes narcolepsy, and is it genetic?
Narcolepsy is believed to result from a combination of genetic predisposition, autoimmune processes, and environmental factors. Narcolepsy can be caused by loss of brain cells that produce hypocretin (orexin), a chemical that keeps you awake and regulates REM sleep. It is thought to involve an autoimmune process triggered by infections or environmental factors (toxins or psychological stress) in genetically susceptible individuals. Genetics also plays a role, but it is not purely inherited.
Secondary narcolepsy is a type of narcolepsy that develops when the hypothalamic region of the brain is damaged. This damage may result from conditions such as traumatic brain injury, stroke, brain tumours, or other disorders affecting the hypothalamus. Although relatively uncommon, such damage can increase the risk of narcolepsy.
How is narcolepsy diagnosed, and what tests are used?
The diagnosis of narcolepsy is based on the patient’s sleep history and symptom review, sleep logs, as well as overnight sleep studies and multiple sleep latency tests (MSLT). The overnight sleep study measures brain waves, breathing, heart rate and movements. The Multiple Sleep Latency Test (MSLT) measures how quickly a person falls asleep during the day and whether REM sleep occurs abnormally early.
According to the American Academy of Sleep Medicine’s International Classification of Sleep Disorders, narcolepsy type 1 is distinguished by sleepiness plus cataplexy and a positive multiple sleep latency test (MSLT), or sleepiness plus hypocretin (orexin) deficiency in the CSF. Narcolepsy type 2 requires sleepiness and a positive MSLT, the absence of cataplexy and normal hypocretin (orexin) levels in the CSF. And the hypersomnia and/or MSLT findings must not be better explained by another sleep, neurologic, mental, or medical condition or by medicine or substance use.
A positive Multiple Sleep Latency Test indicates that a person falls asleep unusually quickly during the day and often enters rapid eye movement (REM) sleep earlier than normal (in less than 15 mins). Normally, most people take at least 10 to 20 minutes to fall asleep, and they don’t usually go straight into REM sleep during a nap. Specifically, the test is considered positive when the average time it takes to fall asleep across five scheduled daytime naps is less than eight minutes, and the person enters REM sleep in at least two of those naps. This pattern suggests abnormal sleep regulation and is strongly associated with narcolepsy.
What treatments are available for narcolepsy, and how effective are they?
The treatment of narcolepsy focuses on managing symptoms rather than curing the condition, as there is currently no definitive cure. Management typically combines medications, lifestyle adjustments, and supportive measures. Medications are the mainstay of treatment. Stimulants are often prescribed to improve alertness and reduce excessive daytime sleepiness. In more severe cases, stronger stimulants like amphetamines or methylphenidate may be used, though they require close monitoring due to potential side effects.
For cataplexy, sleep paralysis, and hallucinations, sodium oxybate and pitolisant are considered first-line medications and are quite effective. Antidepressants may also be used to help control cataplexy and related symptoms.
Alongside medication, lifestyle adjustment strategies also play an essential role. Patients are encouraged to maintain regular sleep schedules, take short planned naps during the day, and avoid situations that may trigger sudden sleep episodes. Good sleep hygiene, including limiting caffeine or alcohol before bedtime and creating a restful sleeping environment, is also important. Regular exercise, a balanced diet, and stress management techniques may further improve overall well-being. Education and support are equally valuable. Patients and their families benefit from understanding the condition and its impact on daily life. Workplace or academic accommodations, such as flexible schedules or nap breaks, can greatly enhance functioning. Support groups and counselling can also help individuals cope with the psychological and social aspects of living with narcolepsy.
There is no established cure for narcolepsy. It is usually a lifelong condition, but symptoms can be controlled much more effectively now than in the past with medications, lifestyle changes and supportive measures.
Are there any potential complications or medical problems associated with narcolepsy?
Narcolepsy can lead to a range of complications and comorbidities that affect both physical and mental health. Individuals with the condition are more likely to experience disrupted nighttime sleep, which can contribute to chronic fatigue and difficulty concentrating during the day. The sudden sleep attacks and cataplexy episodes associated with narcolepsy increase the risk of accidents, particularly while driving or operating machinery. Epidemiological data suggest that individuals with narcolepsy have a three- to fourfold higher likelihood of involvement in motor vehicle accidents. People with narcolepsy also face a higher risk of mental health conditions, including depression, anxiety, and attention deficit disorders. Additionally, there is an increased risk of obesity and metabolic disorders, as the condition can interfere with normal appetite regulation and physical activity. Cardiovascular problems such as hypertension and having abnormal heartbeats are also more common, possibly linked to disrupted sleep patterns.
What safety precautions can be taken to prevent accidents or injuries related to sudden sleep attacks?
Several safety precautions can be implemented to prevent injuries. When driving, it is advisable for people with narcolepsy to avoid driving when sleepy or during periods of drowsiness, and some may need to consider alternative transportation options. Engaging in safety measures at work, particularly in roles involving heavy machinery or operating vehicles, is essential, and employers may provide modified duties or allow scheduled naps for affected employees. Environmental adjustments, such as keeping living and working spaces well-lit, removing tripping hazards, using supportive furniture, and non-slip mats and handrails, can further minimize injury risks. The affected individual can also use alarms or reminders to stay alert.
Are there ongoing research studies or clinical trials for narcolepsy treatments in Nigeria?
Currently, there are no ongoing research studies or publicly registered clinical trials on narcolepsy treatment in Nigeria. Most narcolepsy research and clinical trials are concentrated in Europe, the U.S., and Japan. In Nigeria, narcolepsy awareness and diagnosis are still quite limited. Despite these limitations, some case reports have been published highlighting the challenges of diagnosing and managing narcolepsy in resource-limited settings. Likewise, a study conducted at the Lagos University Teaching Hospital examined sleep problems among psychiatric outpatients, focusing on hypersomnia and narcolepsy. The findings indicated a higher prevalence of these conditions compared to the general population, underscoring the need for improved diagnostic practices.
How true is it that narcolepsy only affects sleep, or do individuals with the condition just need to sleep more?
This is a common misconception about narcolepsy. Narcolepsy is not about needing more or extra sleep. Individuals with narcolepsy already sleep normal or even longer hours, but they remain excessively sleepy and persistently tired because the brain’s ability to regulate sleep-wake cycles is faulty, and no specific or extended periods of sleep can fully relieve the sleepiness. Furthermore, symptoms such as cataplexy, sleep paralysis, and hallucinations demonstrate that narcolepsy affects more than just the sleep duration.
How best can families and groups support individuals with narcolepsy?
Families and support networks play a crucial role in helping individuals with narcolepsy manage the condition and maintain quality of life. Offering empathy and emotional support is crucial, as narcolepsy is often misunderstood as laziness or oversleeping. Encouraging open communication allows the person to express their needs, limitations, and experiences without fear of judgement. Practical support includes helping establish structured daily routines that accommodate regular sleep and short naps and assisting with safety measures, such as avoiding driving during periods of sleepiness or ensuring safe environments at home and work.
Families can also help monitor symptoms and treatment effectiveness, supporting adherence to prescribed medications or behavioural strategies. Social support is equally important. Friends and colleagues can reduce stress and embarrassment by fostering inclusive environments and accommodating the person’s unique needs. Educating themselves about narcolepsy helps families recognize triggers, reduce stigma, manage fatigue, and respond appropriately to sudden sleep attacks or cataplexy episodes.
Is it true that it is a risk factor for schizophrenia and poor cardiovascular health?
Yes, narcolepsy has been linked to an increased risk of certain health problems, including schizophrenia and cardiovascular issues. It is associated with poor cardiovascular health. People living with the condition often experience sleep fragmentation and metabolic changes, which can contribute to obesity, high blood pressure, and increased risk of heart disease and stroke. Additionally, the excessive daytime sleepiness and irregular sleep–wake cycles can negatively influence lifestyle habits, further raising cardiovascular risks. People with narcolepsy have been associated with a higher risk of developing psychiatric disorders such as schizophrenia-like psychosis, depression, and anxiety. This connection is thought to arise from overlapping disruptions in brain chemistry, particularly involving neurotransmitters like dopamine and serotonin, which affect both sleep regulation and mental health.