Central Hypoventilation Syndrome (Ondine’s Curse)

What is Central Hypoventilation Syndrome (Ondine’s Curse)?

In myth, Ondine (or for some, Undine) is a water sprite who falls in love with an human man. She makes a pact to make sure that if he is ever unfaithful, he will pay for his misdeeds with his life. When the man leaves her for his first love, Ondine flees and is later captured. Her uncle, the king of the water nymphs, curses her husband, saying that he must now “˜remember to breathe.’ The man dies when he finally sleeps, for he cannot remember to draw breath.

While it is just a story, for some people Ondine’s curse is a reality. While they do not “˜forget’ to breathe, their body does lapse into fits of hypoventilation, or breathing that is non-present or too slow to sustain bodily function. The defining factor of CHS is the loss of autonomic control of the patient’s breathing, so they eventually wake themselves or die of suffocation in their sleep.

Ondine’s curse has a number of causes but in many cases it is unavoidable and does not have many options for treatment. However, this does not stop networked doctors and specialists from coming together to help the sufferers cope with and survive their daily (and nightly) lives. Despite being rare, its effects on people are great and demand attention, especially since it proves fatal to many people, including children, who are diagnosed.

CHS has only a thousand recorded cases in the past decade, according to studies from 2008. Its rarity makes it relatively hard to study and diagnose, but many cases have been recorded, studied, and even documented to bring awareness to the issue. Many attempts to educate and assist people with the disease have been made, including an official CCHS Foundation and a short film called “Our Curse.”

Although there is no cure, with the proper medical attention and support, patients diagnosed with Ondine’s curse can survive with ventilators and life support machines, and lead mostly normal lives during the day. The disease’s impact can stretch farther than the respiratory system, resulting in a variety of other issues that require specific and unique assistance from doctors and caretakers both. While the disease is not inherently fatal on its own, most children born with CCHS do not survive past infancy.

Symptoms of Central Hypoventilation Syndrome

Ondine’s curse has a long track record of being mistaken or misdiagnosed as other diseases. It shares a number of symptoms with diseases or syndromes like ROHHAD or other forms of sleep apnea. Because of this, many cases and patients that truly have CHS may be overlooked for a simpler diagnosis, resulting in mistreatment or even further complications.

In late-onset and mild forms of CHS, the symptoms may not be noticed until later in life. This may require an official diagnosis from a doctor to begin treatment. This makes it necessary to understand the symptoms in case you or a loved one is diagnosed with a form of sleep apnea. The symptoms of CHS can include, but are not limited to:

Abnormal breathing

The most obvious symptom of CHS is slow, shallow, or reduced breathing. While most patients only experience abnormal breathing patterns during sleep, some severe cases result in improper breathing and oxygenation during their waking hours as well.

Vision problems

Problems with eyesight and vision are common in CCHS patients. From reduced depth perception to the need for corrective lenses, CCHS has shown to affect more than just the respiratory system.

Learning disabilities

If occurring in childhood, a patient may have learning disabilities or developmental delays due to associated damage to their hormones. They may also experience fainting and even seizures.

Cardiovascular system problems

Some patients with CCHS may experience cases in which their heart stops beating, so it is important to do extensive checks on their cardiovascular system to ensure their heart is working properly.

Oxygen deprivation

This can be caused by improper breathing, and may result in discolored skin, headaches, drowsiness, and fatigue.

Cancer

Some patients diagnosed with CCHS later develop neural crest tumours such as neuroblastomas. These illnesses require specific, special attention such as surgery and chemotherapy, and can prove fatal if left untreated.

Congenital forms

While many of these symptoms may not appear in cases of acquired central hypoventilation syndrome, patients with the congenital form of the disease are often more prone to the serious, more dangerous side effects of the disease. Despite having the same core problem, CCHS often proves to display more dangers than its acquired counterpart, and must be treated extremely carefully, even in its mild cases.

Networks and foundations are available to help record and determine cases of Ondine’s syndrome, specifically to avoid misdiagnosis and gain a better understanding of how many people actually have the disease. The more people that are diagnosed properly and treated for Ondine’s curse specifically, the better understanding doctors and specialists can have of it.

Central Hypoventilation Syndrome Causes

In cases of CCHS, the congenital form of CHS, the presentation usually relies on a mutation passed along through genetics, one that later manifests as an actual disease. The mutation occurs during the development of the nervous system and can vary depending on the patient.

The gene responsible for CCHS has been isolated as PHOX2B, a gene that handles a large part of prenatal development. It is a dominant mutation, meaning only one gene has to be affected for the disease to manifest and present in the child. Adults with the gene are advised to undergo genetic counseling before having any more children.

Children with CCHS may experience severe cases of apnea in infancy, and may even develop tumors or lesions because of the disease. Ondine’s curse is frequently misdiagnosed, and the progression and effects of the disease often cause death within the first few months of life. Because of this, few cases of congenital CHS are documented past birth.

Not all cases of CHS are congenital, however, and some may experience symptoms later in life. This form of the disease is called acquired central hypoventilation syndrome, or ACHS. In these cases, the disease can present itself after damage to the brain or brainstem, which results in the loss of autonomic breathing control. Trauma can occur during an accident, stroke, though damage from cancer, and even from poisoning, whether malicious or through chronic alcoholism.

CHS affects males and females in equal numbers, so there is no documented sex bias. In some mild cases, the disease may not present itself until after infancy, resulting in accidents during anesthesia or sedation. It is predicted that the number of diagnosed individuals is far from the true number of cases, since CHS is so easily overlooked or misdiagnosed by medical professionals.

Treatments of Central Hypoventilation Syndrome

Sadly, there is no cure for Ondine’s curse, or any of its subcategories. However, there are treatments to help sufferers of the disease survive and cope, as well as studies in how to better understand and treat the disease with modern medicine. Standard therapies and specialists can assist the patients and their families, and provide services to those diagnosed with CHS.

Oxygen therapy and medicine has been used to treat CHS and encourage better respiratory health, but the most common course of action is to use the assistance of a ventilator. In many cases, this requires a tracheostomy, or an incision to the windpipe to assist in breathing. However, many strides have been made in this process, and there are now methods that do not involve a tracheostomy at all.

With an endotracheal tube, a ventilator can be used through an instrument inserted in the mouth, whereas it would otherwise be inserted in the throat. However, extended use of ventilators can prove problematic for patients, especially in cases where they develop pneumonia or infections. This can be a serious setback for patients with serious CHS who have trouble breathing even when they are awake.

Another form of treatment is diaphragm pacing. This involves electrical stimulation of the nerves in the lungs to encourage breathing. It is a common treatment in other forms of sleep apnea, and has proven to be a promising form of treatment for CCHS and ACHS alike. It is an alternative to mechanical ventilation, and is preferable and less invasive to some patients.

Even though there is no definitive “˜cure’ to central sleep apnea or CHS specifically, attempts to make patients more comfortable and healthy have been made by medical professionals and supportive organizations alike. The strides taken have been impressive, and many fundraisers and studies encourage the progression towards a better solution. Raising awareness towards this disease is also a primary goal, so that undiagnosed sufferers can come forward and gain the same support and treatment plans.

Central Hypoventilation Syndrome Prevention

Since the disease is often congenital, it is often unpredictable and therefore non-preventable. The best course of action is to recognize symptoms early and take action quickly to avoid misdiagnosis or accidents during sedation or sleep. Sufferers with mild cases or late-onset congenital CHS should be aware of their symptoms and keep track of their experiences in case a diagnosis of sleep apnea becomes a case of CHS.

The mutation of the gene responsible for CCHS is passed on 50% of the time, so if it is believed that you or someone else possesses the dominant mutation gene for CCHS, advise them to seek gene therapy before having children or donating eggs/sperm. The only prevention for CCHS is done before conception, since the gene activates early and plays a large part in prenatal development.

In cases of acquired central hypoventilation syndrome, it can be both preventable and unpredictable. Alcohol abuse should be avoided, since it can cause damage to the brain or brainstem that can result in Ondine’s curse. One of the first recorded cases of CHS was caused by alcohol abuse and damage to the woman’s neurological system.

Steps should be taken to avoid vehicular accidents or accidental poisoning, on the off chance it may cause a case of ACHS. While it is impossible to predict if an accident or experience will cause this disease, taking action against harm can improve health in a number of unrelated ways as well.

The number of people coming forward with Ondine’s curse rises by the day, as more and more people recognize the symptoms and realize their diagnosis sooner. Doctors are also becoming more aware of the disease and can, therefore, help their patients get proper help and support from networks and foundations when searching for more information.

Studies are being done on the disease to help determine better methods of treatment, and as awareness for CHS and its counterparts is boosted, the chances of solving the issue become better. If you believe you or a loved one may have Ondine’s curse, it is better to talk to a medical professional and get a medical diagnosis than to leave it untreated or misdiagnosed.

The disease is fatal if left untreated, and every bit of information on a patient’s experiences and treatment can help specialists find the next step in their treatment plans.

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Last Reviewed:
September 17, 2017
Last Updated:
November 29, 2017
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