Prevention and Treatment


Non-24 is a circadian rhythm disorder

Non-24 is a circadian rhythm disorder. Your circadian rhythms are controlled by your master body clock and tell you when to sleep, when to wake, when to eat, among other things.

In most people, the master body clock runs slightly longer than 24 hours. What this means is that rather than cycle on a 24-hour day, most people's natural rhythms actually cycle a bit longer. Whether the cycle runs two minutes or 30 minutes longer, if you have Non-24 these minutes add up day after day, a few one day adding to a few more the next, eventually causing a noticeable change in the times during the day when your body expects to sleep and expects to be awake.

Though Non-24 may appear to be a sleep disorder, it isn't. It's actually a serious, chronic circadian rhythm disorder very common in people who are totally blind, and it can arise at any age. Currently, there are 1.3 million people who are legally blind in the United States. Of the legally blind, 130,000 have no light perception (i.e., totally blind), and as many as 70% suffer from Non-24.

Difficulty at night and challenges during the day

Non-24 brings about two significant symptoms.

First is a profound inability to sleep or to stay asleep at night, and the second is an overwhelming urge to sleep during the day. Both of these changes occur because the internal body clock is out of sync with the 24-hour day-night cycle, which is due to the internal master clock continuously shifting in and out of alignment with the 24-hour day-night cycle. And when poor sleep happens, sleep deprivation may make it difficult to focus on the task at hand.

Non-24 comes about when the master body clock runs on its own natural rhythm. Hence the name, Non-24, which indicates a master body clock that is not 24 hours long. For unknown reasons, most people's body clock runs a little longer than 24 hours, which means most people could have Non-24 to some degree. The difference is that for sighted people, environmental light cues signal the brain to reset the master body clock every day to 24 hours.

For people who are totally blind, the master body clock runs its natural course. This means that if your body clock runs on a 24.5-hour schedule, today you're 30 minutes behind and tomorrow your body clock will be an hour behind. The next day will be 90 minutes, and so on. Day by day, this time adds up until you're many hours behind, creating a rhythm that's out of sync with the typical day-night cycle. Eventually, your body operates as if night is day and day is night. While you could try to maintain your usual schedule, more often than not you have a hard time sleeping at night and then feel an overwhelming urge to sleep during the day. In time, you once again reach the point when your body clock is in sync with the typical day-night cycle. But then, just as quickly, it moves out of sync again.

The master body clock synchronizes your circadian rhythms

The body clock is your natural timing mechanism, and for most people, sighted or blind, it runs a little longer than 24 hours. Thus, it's a non-24-hour clock. For some, it runs just a few minutes longer, and for others it runs much longer. The reason for this is not known.

For example, if your body clock is 24.5 hours, today you're running a half hour behind. Tomorrow you're an hour behind, and so on, until your natural rhythms have you sleeping during the day and awake at night. This continues and eventually your sleep-wake cycle briefly syncs up with the typical day-night cycle. Then it begins to move out of sync again. Some people experience a full circadian cycle as short as one and a half months. For others, it can be several months before their sleep-wake cycle is realigned with the 24-hour day.

The eye has two functions: to allow us to see images and to take in light. This light then signals the time of day to the brain. In people who are sighted, the non-24-hour master body clock is reset every day to 24 hours in the same way that hands on a clock can be reset. This ensures that the circadian rhythms synchronize to the typical day-night cycle.

For people who are totally blind, there are no such light cues. The body clock is left to run its natural course, with extra minutes adding up day by day until your circadian rhythms are essentially upside down from a typical 24-hour day.

Circadian rhythms are your body's tide. They control its natural ebb and flow. They keep its daily activity in sync with the 24-hour day, as well as the timing of sleep and wakefulness. If the circadian rhythms are out of sync, these hormones can be released at the wrong times of day, creating difficulties sleeping at night, and the urge to sleep during the day.

This is how having circadian rhythms that are out of sync with the 24-hour day can impact the natural ebb and flow of the body.

A complication that can sap your energy

Because its effects are so wide-ranging, Non-24 may hinder the methods you use to get through the day. It may sap your energy. You may suddenly fall asleep at inopportune times, and it may make crucial daily tasks a challenge, such as counting bus stops so you know when to get off.

Living with Non-24 may make you feel as though no one understands what you're going through, and this sense of being alone only makes the effects feel that much worse. The truth is, you're not alone. There are many other people living with Non-24 who are experiencing many of the same challenges you do.

Do you have symptoms of Non-24?

Non-24 is not a sleep disorder. It is a serious, chronic circadian rhythm disorder that can greatly impact your life.

If you have some of the symptoms, whether to a mild or intense degree, you may have Non-24.

A few of the key symptoms are:

  • trouble falling asleep or staying asleep
  • waking up groggy or not feeling as if you've gotten enough rest
  • an overwhelming urge to sleep during the day or falling asleep unexpectedly
  • difficulties in managing school or work
  • problems with concentration

Leber’s Hereditary Optic Neuropathy (LHON) disease

Every patient faces their own journey through life, learning about their condition with the best tools available to them. In the case of a rare disease like Leber’s Hereditary Optic Neuropathy (LHON), those tools can be few and far between, making it even harder for patients to plot the best course for them.

A trained journalist currently doing a PhD on the social aspects of LHON and president of Spanish patient group ASANOL, Pedro García Recover talks to pharmaphorum about his own path from diagnosis to living with LHON and working on behalf of his fellow patients.

A webinar was held on 24 January by Santhera Pharmaceuticals to raise awareness on LHON. You can now download the powerpoint presentation.

LHON diagnosis

Pedro was 14 when he was diagnosed with LHON, a hereditary condition whose symptoms are a rare, rapid and sudden loss of vision that leads to blindness in young adults. The condition can appear at any stage in a person’s life.  Pedro had no pain as the disease took hold, just a sudden – though not total – loss of eyesight in both eyes. Today he can see better with the left eye than the right.

Looking back on that time he recalls the tremendous feeling of uncertainty about what was happening to him as his eyesight began to deteriorate. “I didn’t know what was happening with my eyesight. I couldn’t see like I used to, and the specialist took a long time to resolve this uncertainty,” he says.

Achieving that resolution was not a simple process. To do so he visited medical facilities first in his home city of Almería and then travelled to Granada, Valencia and finally Málaga for answers about why he was losing his sight. It was only on arriving in Málaga that Pedro and his parents were told about LHON and the need to take a genetic test to confirm his diagnosis.

“In Málaga we were fortunate to find good professionals who helped us understand the disease and explained the cause.”

Since then Pedro’s quest to find out more about his condition has even guided his subject choice for a PhD, for which he is focusing on the social aspects of LHON. This taught him that “each LHON patient, regardless of their degree of eyesight, learns to live with LHON and tailors their life to their needs”. He also concluded that in Spain, where people living with LHON might also turn to the National Organisation of the Blind in Spain (ONCE) or the Spanish Federation for Rare Diseases (FEDER), patient associations should combine their efforts to work together.

However, even though he identified the social and political will to make progress in LHON education and treatment, Pedro says there is much more to be done in terms of access to studies and work. Additionally, specialists such as ophthalmologists and neurologists need to know more about the disease, particularly when it comes to “knowing how to understand the feelings of unease that patients and their families have when they search for explanations and diagnosis”.

He adds: “Families and patients have to have support to understand what has happened to them.”

Living with LHON

But even when patients have an LHON diagnosis, confirming that genetic mutations have caused the cells in their optic nerve to stop working and provoke loss of vision, they still have to learn how to live with the condition and understand how it will impact their life.

For Pedro, as an adult with LHON, the condition does place some limitations on the access he has to work. “It is possible to have good academic training and work experience, but visual disability –caused by LHON – is considered a problem for many entrepreneurs with whom I’ve had job interviews,” he explains. The disease also brings with it a financial cost, in terms of obtaining things like accessible telephones, large computer screens and different kinds of lenses.

“As for care at home, we buy healthy food – products with properties such as anti-oxidants and vitamins, fruit, vegetables, fresh meat and fish to ensure a varied and healthy diet,” he says.

In addition to such items, he also relies on new technology for assistance, finding his iPhone particularly useful for accessing information. Beyond that, social networks are “a very interesting tool at this time”, despite the need for further progress in terms of their accessibility.” They enable patients to connect, share and update information. On the other hand, they also require patients to have certain skills to use them correctly.”

LHON in Spain

Today in Spain there are several centres that can treat people with LHON, but the facilities available are a combination of private and public ones, generally located in large cities like Barcelona, Madrid or Seville, and access can depend on the family’s resources. Pedro says: “I’m very concerned about people who live in small or medium-sized cities, as normally doctors know very little about the disease. In big cities, there are large hospitals and a greater likelihood of doctors being able to diagnose LHON compared to a small city or town.”

To improve the knowledge of those outside the specialist centres, patient group ASANOL collaborates with laboratories and doctors to enhance their knowledge of the disease. For people living with LHON the non-profit organization offers information when the disease starts to present and LHON experts who can address clinical matters. To bring patients and their families together, the group holds a bi-annual social meeting in Spain.

Although only running for eight years the group has international expansion in its sights and is increasingly opening up across Europe. Looking further afield it has also formed partnerships in Latin America.

“We have helped to try and create patient organisations in some countries, although it isn’t easy doing this from Spain because of the legislation and structure of each country in Latin America. We contacted ALIBER, the Latin American Alliance of Patients with Rare Diseases, to help us provide services to people affected by LHON in Latin America.”

Adjusting your path in life

As a journalist, Pedro is keenly aware of how little media coverage LHON currently attracts. “We need more attention from journalists and media companies on rare diseases. Our sector must also become more professional and offer the media good quality news on which they can focus their attention.  What goes untold is unknown; it’s invisible.”

Although he’s reluctant to hand out advice, Pedro says he has learned a number of lessons from living with LHON. Among these is the important adjustment challenge that newly-diagnosed patients will face as they psychologically start to deal with their condition. “I usually use a phrase that I like because of how real it is: when the disease enters your life, change the intended road map.”

About the interviewee:

Pedro García Recover was born in Almería in 1978. During his adolescence he played handball until he was 14. It was at this age that he developed LHON. He graduated in journalism in 2004 and in 2009 he was awarded a master’s degree in social communication. He is currently doing a PhD at the National Distance Education University (UNED) on “Law and Social Sciences”. His thesis is on psycho-social aspects of Leber’s hereditary optic neuropathy.

Pedro García has spent a large part of his working life communicating with non-governmental organisations. He has worked in radio for over 5 years, presenting and directing programmes. He is a speaker, lecturer and expert in social communication and is involved in the management and strategy of social networks. He has participated in a number of national and international forums on the topics of human rights and people with disabilities. He has been working for the National Organisation of the Blind in Spain (ONCE) since 2016.

Pedro García is currently President of ASANOL, a Spanish organisation for those affected by Leber’s hereditary optic neuropathy (LHON). He was elected President in March 2018.