Introduction
Sudden unexplained nocturnal death syndrome (SUNDS) is a unique medical phenomenon. The syndrome is characterized by the unexplained death of a healthy individual during sleep. The most commonly affected people are young adults in the Asian region. People with no underlying health issues exhibit no symptoms, but they suddenly feel lifeless in bed. The prevalence of SUNDS is high in the Southeast Asian region. Genetic factors, lifestyle, and cultural elements play an important role in exacerbating the risk of the condition. Certain investigations help detect the causes of SUNDS and identify the links with other diseases, such as cardiac arrhythmias and other heart diseases. The article delves into the existing knowledge of SUNDS and its various aspects. The other factors described in the article are its causes, symptoms, diagnosis, and treatment.
What Is Sudden Unexplained Nocturnal Death Syndrome?
Sudden unexplained nocturnal death syndrome is the leading cause of death in young and older adults. Around 15 to 20 percent of deaths are due to SUNDS. An individual with no pre-existing health condition or any symptoms who dies during nighttime sleep hours is called sudden unexplained nocturnal death syndrome. The first case of SUNDS occurred in the Philippines in 1917.
What Are the Different Names of Sudden Unexplained Nocturnal Death Syndrome?
According to different cultures, there are different names for sudden unexplained nocturnal death syndrome, which are as follows:
-
Lai Tai: The alternative name of SUNDS in Thailand is Lai Tai which means death during sleep. Lai Tain first occurred in Singapore workers in 1990.
-
Bangungut: The other name of SUNDS in the Philippines is Bangugnut. The meaning of Bangungut is an individual is in a nightmare and believed to cause sudden death during sleep.
-
Pokkuri Death: In Japan, the SUNDS is also called Pokkuri death. Around 60 to 70 percent of sudden deaths in Japan are due to cardiac diseases. The meaning of Pokkuri's death is sudden death.
-
Cotard’s Syndrome: In some regions of the world, the alternative name of SUNDS is Cotard’s syndrome. An individual with Cotard syndrome is associated with delusions of being dead, which are associated with SUNDS.
-
Associated Sudden Death Syndrome: Among the Asian population, the associated sudden death syndrome term is used to highlight the high prevalence of these cases.
-
Sudden Adult Death Syndrome (SADS): The term describes the sudden death of adult people including the nocturnal cases.
-
Brugada Syndrome: This syndrome is not a synonym or alternative name of SUNDS, but it is a heart disease that leads to sudden unexplained nocturnal death syndrome.
What Are the Causes of Sudden Unexplained Nocturnal Death Syndrome?
Some researchers are still investigating the reason behind the occurrence of SUNDS. However, several factors can contribute to the medical phenomenon as follows:
-
Cardiac Arrhythmias: If an individual has irregular heart rhythms like ventricular tachycardia, it can disrupt the normal heart pumping system. The condition can cause sudden cardiac death.
-
Autonomic Nervous System Dysfunction: The autonomic nervous system regulates the involuntary functions of the human body, such as heart rate. The disturbances in these involuntary functions can cause SUNDS.
-
Genetic Predisposition: Some genetic variations can make people more prone to cause heart arrhythmias or other heart conditions. This ultimately leads to SUNDS.
-
Electrolyte Imbalance: Imbalance in electrolytes such as calcium, potassium, and magnesium can disturb the heart's electrical system, affecting the heart rate and leading to cardiac arrhythmias.
-
Sleeping Disorders: Sleep-related disorders such as sleep apnea and other abnormal sleep patterns can influence the formation of SUNDS.
-
Cultural and Lifestyle Factors: The syndrome is prevalent in specific ethnic groups. Lifestyle changes such as dietary habits, smoking, and alcohol consumption can affect heart rhythm and contribute to the occurrence of SUNDS.
-
Substances and Toxins: If an individual ingests certain substances or toxins, it can trigger fatal heart events during sleep.
-
Stress: An individual with emotional stress might trigger heart events in susceptible individuals.
-
Inflammatory Process: Inflammation of the heart muscle might affect the electrical conduction system. This may cause the heart to affect the pumping system and lead to cardiac arrhythmias.
What Are the Signs and Symptoms of Sudden Unexplained Nocturnal Death Syndrome?
An individual with SUNDS does not experience any symptoms. However, some symptoms might be associated with the formation of the condition. However, not every individual with the condition has symptoms. The potential signs and symptoms associated with SUNDS are as follows:
-
Nocturnal Death: It is the most prevalent clinical feature. An individual with the condition might die during sleep. Without any cause, the person was found deceased in their bed.
-
No Existing Health Issues: The affected people are young and older. The patient with SUNDS is healthy, with no known medical disorders or other risk factors.
-
Silent Death: The symptom of silent death is used because there are no screams or distress associated with the condition.
-
Discomfort: Some patients may feel the sensation of discomfort before going to sleep. However, it is not enough to predict the occurrence of the condition.
-
Autonomic Symptoms: The symptoms include dizziness, palpitations, and shortness of breath before sleep.
-
Cardiac Arrhythmias: An individual with the condition may experience irregular heart rhythms.
How Is Sudden Unexplained Nocturnal Death Syndrome Diagnosed?
The diagnosis of SUNDS is challenging. However, the diagnostic process of SUNDS includes the following steps:
-
Autopsy: A thorough post-mortem examination is done to rule out the signs of trauma or anatomical abnormalities that might lead to the death of the person.
-
Family History: The healthcare provider may ask the patient's family members about any family history of SUNDS or other heart disorders.
-
Toxicology Screening: The healthcare provider may conduct toxicology tests such as blood tests or urine tests to find the presence of drugs that lead to death.
How Is Sudden Unexplained Death Syndrome Treated?
The treatment options for SUNDS are as follows:
-
Cardiac Monitoring: The healthcare provider may monitor the heart to find out or treat irregular heart rhythms.
-
Lifestyle Changes: People with the condition should adopt healthy lifestyle modifications such as regular physical activity, stress management, limiting alcohol, no smoking, a balanced diet, and no tobacco.
-
Education and Awareness: Raising awareness among people about SUNDS can encourage them to seek medical attention.
The healthcare provider also prescribes some medications to manage underlying heart conditions.
Conclusion
In conclusion, sudden unexplained nocturnal death syndrome is a challenging medical phenomenon to understand. Healthy people with the condition die during sleep without any known medical condition or other cause. The young, healthy people are most commonly affected. The condition can be managed by adopting healthy lifestyle modifications, managing underlying cardiac events, and genetic screening. Raising awareness among people about SUNDS can encourage them to seek medical treatment for the condition.
