Sudden unexpected death syndrome

Not to be confused with Sudden cardiac death.

SUNDS
Classification and external resources
Specialty
ICD-10	R96.0
Patient UK	Sudden unexpected death syndrome

Sudden unexpected death syndrome (SUDS), sudden unexpected nocturnal death syndrome (SUNDS), sudden adult death syndrome (SADS), or bed death is sudden unexpected death of adolescents and adults, many during sleep. Sudden unexplained death syndrome was first noted in 1977 among Hmong refugees in the US. The disease was again noted in Singapore, when a retrospective survey of records showed that 230 otherwise healthy Thai men died suddenly of unexplained causes between 1982 and 1990: In the Philippines, where it is referred to in the vernacular as bangungot, SUNDS affects 43 per 100,000 per year among young Filipinos. Most of those affected are young males.

Causes

No cause of death is found, even after extensive examination in 5% of cases.

A sudden death in a young person can be caused by heart disease (including cardiomyopathy, congenital heart disease, myocarditis, genetic connective tissue disorders, mitral valve prolapse or conduction disease), medication-related causes or other causes.

Rare diseases called channelopathies may play a roles such as long QT syndrome (LQTS), Brugada syndrome CPVT (catecholaminergic polymorphic ventricular tachycardia), PCCD (progressive cardiac conduction defect), early repolarisation syndrome, mixed sodium channel disease, and short QT syndrome.

In some cultures, SUNDS has been cloaked in superstition. Many Filipinos believe ingesting high levels of carbohydrates just before sleeping causes bangungot. It has only been recently that the scientific world has begun to understand this syndrome. Victims of bangungot have not been found to have any organic heart diseases or structural heart problems. However, cardiac activity during SUNDS episodes indicates irregular heart rhythms and ventricular fibrillation. The victim survives this episode if the heart's rhythm goes back to normal. Older Filipinos recommend wiggling the big toe of people experiencing this to encourage their heart to snap back to normal.

In the Philippines, most cases of "bangungot" have been linked with acute hemorrhagic pancreatitis by Filipino medical personnel although the effect might have been due to changes in the pancreas during post-mortem autolysis. In Thailand and Laos, bangungot (or in their term, sudden adult death syndrome) is caused by the Brugada syndrome.

Features

The condition appears to affect primarily young Hmong men from Laos (median age 33) and northeastern Thailand (where the population are mainly of Laotian descent).

Treatment

The only proven way to prevent death is by implantation of a cardiovertor defibrillator. Oral antiarrhythmics such as propranolol are ineffective.

Folk beliefs

This phenomenon is well known among the Hmong people of Laos, who ascribe these deaths to a malign spirit, dab tsuam (pronounced "da cho"), said to take the form of a jealous woman. Hmong men may even go to sleep dressed as women so as to avoid the attentions of this spirit.

Hmong people believed that rejecting the role of becoming a shaman, they are taken into the spirit world.

Bangungot is depicted in the Philippines as a mythological creature called batibat or bangungot. This hag-like creature sits on the victim's face or chest so as to immobilize and suffocate him. When this occurs, the victim usually experiences paralysis. It's said that one should bite their tongue and wiggle their toes to try to get out of this paralysis or they may die from suffocation.

Nomenclature

Name variations in English

Name	Acronym	Notes
sudden unexpected death syndrome	SUDS
sudden unexplained death syndrome	SUDS
sudden unexpected nocturnal death syndrome	SUNDS
sudden unexplained nocturnal death syndrome	SUNDS
sudden adult death syndrome	SADS	(parallel in form with SIDS)
sudden arrhythmia death syndrome	SADS
sudden arrhythmic death syndrome	SADS
sudden arrhythmic cardiac death syndrome	—
bed death	—

Names in different languages

Term	Language	Notes
bangungot or uom	Filipino	The term originated from the Tagalog word meaning "to rise and moan in sleep". It is also the Tagalog word for nightmare.
dab tsog	Hmong
lai tai	Thai	(Thai: ใหลตาย; meaning "sleep and die")
dolyeonsa	Korean
pokkuri disease	Japanese
ya thoom	Arabic
albarsty (Kyrgyz: албарсты)	Kyrgyz

See also

• Brugada syndrome
• Sudden infant death syndrome
• Yunnan sudden death syndrome
• Sleep paralysis
• Freddy Krueger