Narcolepsy: W5 Fact File
Published Saturday, November 2, 2013 9:00AM EDT
Narcolepsy is an under-recognized and underdiagnosed condition. Many patients say it takes years to get a proper diagnosis. Some cases are mistakenly labelled as ADHD or depression. Children struggle in school and can be placed in classes for the learning disabled. Yet many teachers, parents even doctors may not realize is that the symptoms are due to narcolepsy.
Some of the families we interviewed took us it took over a year to get properly diagnosed. Once diagnosed, patients often struggle to get the right mixture of medications, to help patient stay awake and sleep properly, while preventing the cataplexy attacks. Doctors are hoping to find better treatments.
The increase in cases of narcolepsy in various countries is leading to more research into the condition with the possible link to H1N1 -- the first time that a virus has been directly linked to Narcolepsy. We believe people should be aware of this research. The flu can cause a lot of nasty problems, some we still don’t yet know about.
It also raises questions about the possible role of a vaccine used only for a short time during the 2009 pandemic.
NOTE: There is NO LINK with the annual flu shot which remains an important public health tool.
What exactly is Narcolepsy and Cataplexy?
The most important symptom of narcolepsy is sleepiness. Patients can have an irresistible urge to sleep during the day. They can fall asleep while on the phone -- even at work.
Patients can also have problems sleeping through the night. Some can experience hallucinations and sleep paralysis -- where they can’t move their bodies even though they are awake.
Cataplexy is found in about two-thirds of patients. It’s a sudden weakness in the muscles of the body. And it’s triggered by intense emotions – laughter, love, anger even pride.
The more recent cases seen in younger children can also involve other symptoms. Here’s a study from Italy with photographs and videos.
Who is affected by Narcolepsy?
Narcolepsy affects about 1 in 2,000 people in North America However, the doctors believe disorder is likely under-diagnosed, particularly in people with mild symptoms. The disorder usually emerges in late adolescence or early adulthood and generally has a gradual onset, which is what makes the newer cases of rapid severe onset narcolepsy being reported in children so unusual.
Why does it happen?
Most patients with narcolepsy do not produce hypocretin in a deep part of the brain called the hypothalamus. Without this hormone, other chemicals that promote alertness during the day and sleep at night, don’t work properly. Doctors don’t know exactly what destroys the some 70,000 cells that produce the hypocretin. But they suspect the patient’s immune system mistakenly attacks these cells.
Many patients also have a genetic predisposition. The most well-studied of these genes is HLA-DQB1, which provides instructions for making part of a protein that plays an important role in the immune system.
How is Narcolepsy treated?
A diagnosis is confirmed with an overnight sleep study and then a series of nap studies the following day, conducted every two hours. If patients fall asleep quickly and go into rapid eye movement (REM) sleep fast, that is a marker for narcolepsy.
Narcolepsy is incurable at the moment. There are medications that boost alertness- and others that help control the cataplexy.
Treatment for children is a bit trickier because many of these drugs have been tested in adults, not in children, among whom the condition has been considered very rare. Doctors are hoping new research leads to better treatments and hopefully better ways of preventing new cases of narcolepsy. But with proper treatment Doctors say even children can lead a full productive life.
How Could the Swine Virus alone have triggered Narcolepsy?
Dr. Emmanuel Mignot at Stanford University in Palo Alto California has been collecting blood samples from children who developed Narcolepsy during the swine flu outbreak from around the world. He’s found that in some countries, like China, there was a swell in new pediatric cases of narcolepsy that followed h1N1 and seemed to be associated with the flu infection itself, not with flu vaccinations. Few* children in China were vaccinated against the pandemic strain of H1N1.
His theory still needs to be confirmed. But he says there is historical precedence. For several years after the 1918 Spanish flu pandemic, medical authorities described a condition they labelled “encephalitis lethargica a disorder that involved excessive daytime sleepiness. The Spanish flu was also an H1N1 type influenza.
The findings suggest that getting vaccinated against H1N1 and avoiding infection with the flu may help protect patients who have a genetic susceptibility to narcolepsy.
Which countries are finding increases of Narcolepsy linked to actual H1N1 vaccinations?
Finland, Norway Ireland, France, Sweden and the U.K. have all seen spikes in narcolepsy and found a high number of cases in children following immunization with the Pandemrix H1N1 Vaccine.
The symptoms linked to that product, say doctors, emerged within days … up to 18 months following vaccination.*
Here are some studies:
This link has not been found with any other pandemic flu vaccine or any other adjuvant. Nor has it been identified with any previous influenza vaccine.
Europe's drugs regulator has ruled Pandemrix should no longer be used in people aged under 20.
Despite the rise in narcolepsy cases linked to the vaccine, doctors caution it’s still rare…with Dr. Mignot citing a risk of 1 case of childhood narcolepsy in Europe per 55 thousand vaccinations.
We underline, however, that a definitive link had not as yet been proven between the development of the condition and the vaccine or adjuvant.
Does this concern about a link to narcolepsy extend to any other vaccines?
This scientific scrutiny involves one vaccine with one adjuvant. It has no impact on childhood vaccines that control potential killers like measles and polio whooping cough and diphtheria. Those vaccines remain safe and effective say public health officials.
What about adults?
Finland's National Institute is also reporting a rise in narcolepsy among adults, finding those aged between 20 and 64 who had been vaccinated with Pandemrix were 3 to 5 times more likely to develop narcolepsy than unvaccinated people. French researchers have also noted a similar increase in narcolepsy in adults inoculated with Pandemrix.
Narcolepsy has never been linked to a vaccine before and it came as a surprise says Markku Partinen, a sleep researcher at the Helsinki Sleep Clinic in
Why is this one vaccine with the adjuvant called ASO3 implicated in some cases?
The Pandermix vaccine used an adjuvant called ASO3. It acts as a booster for the vaccination and increases the body’s immune response to it. This meant that only a fraction of the antigen- the part that activates the immune system- is needed to give protection against the virus. .
Adjuvants allow vaccine makers to produce more product in less time. Scientists agree the ASO3 adjuvant in Pandemrix was very potent and it is believed may have boosted both a good immune response. But they are now scrutinizing its possible role in the rise of narcolepsy cases.
Dr. Emmanuel Mignot, who is being funded by GSK to investigate the link, says he believes that in some children who were unknowingly genetically susceptible to narcolepsy (confirmed with a blood test after they became ill) the vaccine or adjuvant may have accidentally triggered some cases of narcolepsy, but there may be other factors involved that scientists aren’t yet aware of. Perhaps this adjuvant, he says was “too strong” in children with a genetic susceptibility to narcolepsy. More research he says is needed.
Have other kinds of adjuvants been linked to Narcolepsy cases?
Another adjuvant MF59 made by Novartis has not been linked to cases of narcolepsy.
Was ASO3 adjuvanted vaccine used in Canada during the swine flu pandemic?
Yes, ASO3 was used in one vaccine given out in Canada in 2009 2010 called AREPANRIX also made by Glaxo SmithKLINE –but it was manufactured at a different facility and has a slightly different formulation.
Arepanrix is a vaccine manufactured by GlaxoSmithKline in Canada. Arepanrix and Pandemrix vaccines are similar in formulation, but not identical. However, the antigens (inactivated virus parts) used in Pandemrix and Arepanrix were produced in different facilities using different manufacturing processes.
Arepanrix was only used during the H1N1 pandemic in 2009/2010 and is no longer being used in Canada.
The Agency continues to monitor for any new reports through the Canadian Adverse Events Following Immunization Surveillance System as well as the FPT Vaccine Vigilance Working Group.
In Canada, given the frequency of narcolepsy in the population, the number of reported cases compared with the number of doses of Arepanrix administered does not suggest a vaccine safety concern. There was less than 1 case of narcolepsy per every million doses given. It is estimated that 11 million doses of Arepanrix were administered.
To date, the number of reported cases of narcolepsy in Canada is 8 total: 3 in adults aged 18 years or older and 5 in children under 18.
What do studies show about the Canadian vaccine and a possible link to Narcolepsy?
So far only one study has been done in Canada, using data from Quebec. The study looked at all narcolepsy and cataplexy cases diagnosed over a 2-year period (January 2009-December 2010) at all sleep and neurology clinics in the province.
Medical records were reviewed. Immunization status was verified in the provincial pandemic influenza registry.
From the study abstract presented at a Sleep meeting in France October 19, 2013:
A total of 23 cases were identified and one additional case with uncertain date of onset, for a rate of 1.5 per million person-years. A cluster of 7 cases was observed among vaccinated persons in the winter 2009-2010, after the second pandemic wave and the mass immunization campaign in the fall. In the base cohort analysis, the 16-week post-vaccination relative risk was 4.32 (95% CI: 1.50-11.12), and was 3.55 (0.89-14.21) in the base SCCS. Estimates were lower when the observation was restricted to the period of pandemic influenza circulation. Conclusions: Results are compatible with an excess risk of approximately one case per million vaccine doses but a confounding effect of the pandemic virus infection cannot be ruled out.
How many studies are underway in Canada to a possible rise in narcolepsy cases?
Scientists at ICES and Sunnybrook will study Ontario cases of narcolepsy and cataplexy following 2009. It's part of a larger international study with the U.S Centres for Disease control and the Brighton collaboration in the UK. They will be targeting cases in those aged 4 to 24, trying to determine if there was an increase in cases and if they were linked to H1N1 exposure, or H1N1 vaccination.
This study is to be completed in 2014 or 2015.
Dr. Manisha Witmans is collecting data on cases along with colleagues from Toronto. This information she says will be available in a few months.
Researchers in Quebec are continuing to analyze the preliminary data in that presentation shown above.
Why don’t we already know if there has been an increase in narcolepsy cases in Canada – whatever the trigger?
Outside of Quebec, there are no national or provincial registries for these sleep disorders. So doctors say it’s a complicated process to track cases and try to figure out what the exposure might have been – whether the symptoms of narcolepsy were there before the swine flu pandemic of 2009 or not. It can also take several years for people to get properly diagnosed with narcolepsy.
Children with milder symptoms may be told they have ADHD or learning problems, delaying the correct diagnosis and treatment.
What is the real risk of Narcolepsy post-H1N1
Doctors say that even with the increased number of cases reported, narcolepsy remains relatively rare. Dr. Mignot calculates there may have been 1 case of narcolepsy linked to a vaccine for every 55,000 children vaccinated in countries that used the Pandremix vaccine with the ASo3 booster adjuvant.
So should I get this year's flu shot?
We underline – this link has nothing to do with the current annual flu vaccine.
Flu vaccines are considered very safe and effective at protecting people, especially those at high risk of complications from the flu.
That’s why public health officials in Canada recommend that all Canadians over 6 months of age get the annual flu shot – to prevent complications like pneumonia, and possibly death.
Priority groups for annual vaccination are: Adults and children with underlying health conditions, including immune disorders, chronic diseases, obesity, and seniors or anyone in a nursing home or chronic care facility pregnant women and Aboriginal People-health care providers police emergency service workers.
This year’s flu vaccine does not contain an adjuvant – that was used during the H1N1 pandemic of 2009-2010.