Kleine–Levin Syndrome: Sleeping Beauty Disease That Messes with Teen Brains

Parents of adolescents are accustomed to complaining about their child's sleeping habits and the difficulty of waking them before noon on weekends. For those with the rare neurological disease Kleine-Levin Syndrome (KLS), however, excess sleeping is just the most obvious feature of a condition that is infuriating, perplexing and difficult to treat.

KLS, also known as sleeping beauty syndrome, often strikes first in a patient's early teens, although onset can happen several years earlier or in adulthood.

People living with KLS can sleep for up to 20 hours per day during episodes that last anywhere from a few days to a few weeks. The disease often seems to appear out of nowhere and is often precipitated by an upper-respiratory tract infection, according to the National Institutes of Health. Although the majority of patients are male, it can affect females as well.

The syndrome has a prevalence of just one to five in a million people, according to Dr. Guy Leschziner, a professor of sleep medicine at the U.K.'s King's College in London and a consultant neurologist at Guy's and St. Thomas' hospitals. He told Newsweek that its rarity makes it more difficult to study.

"[KLS] has been described for a number of years, but to date, we don't fully understand what it is," he said. "One of the great difficulties is that because it is such a rare disorder, it is hard to do a randomized controlled trial, which is very challenging."

Boy sleeping with open laptop
Kleine-Levin Syndrome is a rare neurological disorder that can cause patients, who are generally young people to sleep for up to 20 hours at a time. Pictured, a stock image of a boy sleeping in front of laptop Getty

While KLS patients usually behave normally between episodes, some will have ongoing symptoms, Leschziner added. Although the onset of episodes can be unpredictable, triggers can include sleep deprivation, a concurrent illness or alcohol.

Some researchers believe KLS is an autoimmune condition, Leschziner said. Episodes can occur once every few weeks or months, and are occasionally less frequent, causing those with the condition to miss school, exams, work or social events. The disease often goes into spontaneous remission after an average of 12 to 13 years, but in some cases can go on for longer.

In addition to the profound sleepiness associated with KLS, those with the syndrome often exhibit confusion and changes in appetite, including ravenous hunger, as well as disinhibited behavior and a temporary lack of consciousness of social norms, Leschziner said.

"In the media, they call it 'Sleeping Beauty Syndrome,' but there is nothing beautiful about this condition," Jenny Grossman, a New Jersey-based member of the board of directors of the KLS Foundation, told Newsweek.

Grossman's son Cooper, now 20, was diagnosed with the syndrome at the age of 15 following a bout of the flu, although his family believes his first episode took place two years earlier after he suffered a concussion playing sports.

An illness that upends family life

Grossman said her family was comparatively lucky because her son was diagnosed within a month, following a nine-day hospital stay where clinicians ruled out tumors, a bad drug reaction and a number of other conditions. Doctors wanted to refer him to a psychiatric hospital, which is something that KLS families often experience, according to Leschziner.

Then, Grossman's sister-in-law saw a description of KLS while Cooper was still in the hospital, and the family managed to get an appointment with a New York-based neurologist with experience with the syndrome. For other KLS families, she says, a diagnosis can take up to four years.

"It's a pretty serious condition that most people don't know about," Grossman said. "The medical profession doesn't know much about it."

Grossman described her son's behavior during an episode as analogous to a bear in hibernation. For weeks at a time, she said, those with the condition are awake only long enough to eat or use the toilet, with many becoming agitated or unpleasant if they are woken up or otherwise disturbed by family members.

Although Cooper had no cognitive deficit when he came out of his episodes, others with the condition are not so lucky. Patients often need physiotherapy to recondition themselves after an episode.

The disease's intermittent nature makes it especially cruel, Grossman said, as does the fact that it is essentially a brain injury that is invisible to others.

While there is no cure for KLS, the condition can be managed to an extent with medications such as lithium and amantadine, which are used to limit bouts. There are also anecdotal reports of anti-epileptic drugs being used successfully with KLS patients, according to Leschziner. Researchers have identified a genetic marker that could be connected with the syndrome, but have yet to create a diagnostic test for it.