Kleine-Levin syndrome is a rare sleep disorder that mostly affects males. But recognizing the symptoms in females means timely diagnoses, social support, and treatments that improve quality of life.
Kleine-Levin syndrome (KLS) is a rare disorder that causes bouts of unusual and severe sleepiness. These bouts appear and resolve abruptly, then recur every few months. Episodes can be disruptive to school, social, and professional routines and often occur along with cognitive and behavioral disturbances.
KLS is a rare disease that is even less common in people assigned female at birth. Approximately 70% to 90% of KLS cases affect males.
This relative rarity can delay diagnosis in females, even when typical symptoms are present. But case reports show that females can also have KLS, and they may have additional unique episode triggers and treatment options.
The diagnostic criteria for KLS are the same regardless of sex assigned at birth.
KLS is characterized by recurrent episodes of extreme sleepiness known as hypersomnolence. Each episode may last from 2 days to 5 weeks. During an episode, you might need to sleep as much as 20 hours per day, rising only to eat and use the bathroom.
Flare-ups of KLS are often unpredictable but generally recur within weeks to months.
In KLS, periods of excess sleepiness must be accompanied by at least one of the following:
- cognitive dysfunction, such as confusion, disconnection, or extreme apathy
- altered perception, such as hallucinations or depersonalization
- disordered eating, often extreme hunger or compulsive eating
- disinhibited behavior, such as hypersexuality or irritability
Between hypersomnolence episodes, people with KLS return to their typical sleep, function, behavior, and mood.
Menstrual-related hypersomnia vs. Kleine-Levin syndrome
Doctors now consider menstrual-related hypersomnia (MRH) a subtype of KLS.
Both are rare disorders of recurrent hypersomnolence.
In people with MRH, the first hypersomnolence episodes begin appearing soon after the onset of menses and occur around the same time as menstruation.
Compared to typical KLS, MRH episodes tend to be shorter, lasting about 1 week. Cognitive impairment during episodes may be less severe.
Experts think hormones trigger MRH. In some cases, your symptoms may improve with estrogen-containing contraceptives like birth control pills.
When a KLS episode begins, symptoms appear abruptly and progress rapidly, usually peaking within 24 hours.
Extreme sleepiness is the hallmark of a KLS episode. During a KLS flare, you might need to sleep 18 hours per day or more. This can prevent you from participating in regular social, school, or professional activities.
While awake, people experiencing a KLS episode will have at least one of the behavioral and cognitive symptoms described above. For example, case reports describe compulsive eating of anything edible within reach.
Females appear more likely than males to experience mood disruptions like extreme apathy, while males are more likely to experience hypersexuality. Some people with KLS describe depersonalization or derealization, a marked feeling of unreality or being in a dream-like environment.
Typical KLS episodes can last from days to months but average about 1 to 3 weeks. KLS episodes often recur every few months. Between KLS flares, you will sleep, feel, and behave normally. But you might not have a clear memory of the episodes themselves.
KLS is an extremely rare sleep disorder. If you have unusually increased sleepiness or disturbed sleep, contacting a doctor to review your symptoms may help you get a quicker diagnosis.
To better evaluate your symptoms, a doctor may ask you to keep a sleep and symptom diary for a period of weeks to months. They may suspect KLS if you have clearly defined episodes of needing to sleep more than 15 hours per day, especially if you have mood, cognitive, or behavioral changes at the same time.
They can also order tests to rule out other conditions or refer you to a sleep specialist for further evaluation.
Accurate diagnosis and increased awareness can help support people who have received a diagnosis of KLS.
Treatment is typically supportive, including:
- getting adequate and consistent sleep
- avoiding possible triggers, including alcohol, stress, and exposure to illness when possible
- allowing rest at home in a safe and comfortable environment
- monitoring behavioral, cognitive, and mood disturbances and ensuring safety
There’s no evidence that any single medication is consistently effective in KLS despite trials of stimulants, antidepressants, antivirals, and more. For this reason, a doctor will consider your individual symptoms and circumstances when considering which medications to try.
For example, a doctor may recommend combination oral birth control for females with MRH. According to the American Academy of Sleep Medicine (AASM) 2021 guidelines, clinicians may consider a trial of lithium therapy for adults with KLS. Doctors have also prescribed stimulants like modafinil to try to treat KLS.
If you or your child has received a diagnosis of KLS, you can talk more with your doctor about treatment options based on your specific circumstances.
KLS is an exceedingly rare disorder, but episodes often decrease as the person gets older. However, episodes can sometimes recur for 10 to 20 years or more. KLS may last longer in women than in men.
One
How common is Kleine-Levin syndrome in females?
Kleine-Levin syndrome is an extremely rare disorder, with an estimated incidence of 1 to 5 per million people. There are only about 200 total reported cases in the medical literature.
KLS is also about four times more common in males than in females, who represent just 10% to 30% of cases.
At what age does Kleine-Levin syndrome occur?
KLS usually presents during adolescence and can continue into adulthood. It has been reported in boys as young as 10 years old, though onset in females is often later than in males.
What triggers a Kleine-Levin syndrome episode?
Experts often cannot identify a specific trigger for KLS, but some people experience episodes following:
- fever or infection
- stress
- sleep deprivation
- alcohol use
- head trauma
- physical exertion
- menstruation
- routine vaccination
There may also be a seasonal influence, with first episodes occurring more often in the fall and winter seasons.
KLS is an exceedingly rare sleep disorder. While it mostly affects adolescent males, it can also affect females.
In females with KLS, menstruation may be an additional trigger for episodes of excessive sleepiness. MRH is a subtype of KLS specific to females that may be treatable with estrogen-containing contraceptives.
The overall rarity of KLS, as well as its association with teen boys, may cause delays in evaluation and diagnosis for females with typical symptoms.
Healthy sleep is important for growth and development. Abnormal excessive sleepiness can be a sign of many different sleep, neurologic, and psychiatric disorders, which may be treatable. If you or your child experience problems with excessive sleepiness, it is a good idea to start a symptom diary and talk more with your doctor.