Sudden unexpected death syndrome

Sudden unexpected death syndrome, or Sudden unexpected nocturnal death syndrome (SUNDS), is sudden unexpected death of adolescents and adults during sleep. Sudden unexplained death syndrome was first noted in 1977 among Hmong refugees in the US.[1][2] 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:[3] In the Philippines, where it is referred to in the vernacular as bangungot, SUDS affects 43 per 100,000 per year among young Filipinos. Most of the victims are young males.[4]

Contents

Causes

SUDS has been cloaked in superstition. In Thailand it is particularly believed to be linked to eating rice cakes. 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.[5]

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.[6] In Thailand and Laos, bangungot (or in their term, sudden adult death syndrome) is caused by the Brugada syndrome.[7]

Features

The condition appears to affect primarily young Hmong men from Laos (median age 33)[8] and northeastern Thailand (where the population are mainly of Laotian descent).[9][10] There is a strong hereditary component and the victims tend to die in their sleep. From experience bangungot is the sensation of the victim being fully aware of their surroundings however being unable to move. The victim tries to scream but cannot, and there seems to be a strain on their chest.

Pathology

The cause of this syndrome has been theorized to be a form of Brugada Syndrome.[11][12]

It was noted very early on that the disease had the characteristics of a familial cardiac conduction defect (i.e., a problem with the electrical pathways of the heart),[13] and one study has shown evidence for a long-QT syndrome in populations at risk.[14] Thiamine deficiency is common in the risk population because of diet, and is also a cause of a prolonged QT-interval;[15] but proof that inducible ventricular arrhythmia is the cause of this disease came only with the publication of the DEBUT trial in 2003.[16]

Ongoing genetic studies by Spanish electrophysiologist Dr. Josep Brugada Terradellas show that SUDS results from mutations in the cardiac sodium channel gene. This means that it is a chromosomal problem, which is why it runs in families. Therefore doctors say that families who have kin that have suffered from or died of SUDS must see a heart specialist.

Treatment

The only proven way to prevent death is by implantation of a cardiovertor defibrillator. Oral antiarrhythmics such as propranolol are ineffective.[16]

Folk beliefs

This phenomenon is well known among the Hmong people of Laos,[17] 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.

Bangungot is depicted in the Philippines as a mythological creature called batibat. This hag-like creature sits on the victim's face or chest so as to immobilize and suffocate him.

Names in different languages

See also

References

  1. ^ Centers for Disease Control (CDC) (1981). "Sudden, unexpected, nocturnal deaths among Southeast Asian refugees". MMWR. Morbidity and mortality weekly report 30 (47): 581–4,589. PMID 6796814. 
  2. ^ Parrish RG, Tucker M, Ing R, Encarnacion C, Eberhardt M (1987). "Sudden unexplained death syndrome in Southeast Asian refugees: a review of CDC surveillance". MMWR CDC Surveil Summ 36 (1): 43SS–53SS. PMID 3110586. 
  3. ^ Goh KT, Chao TC, Chew CH (1990). "Sudden nocturnal deaths among Thai construction workers in Singapore". Lancet 335 (8698): 1154. doi:10.1016/0140-6736(90)91153-2. PMID 1971883. 
  4. ^ Gervacio-Domingo, G.; F . Punzalan , M . Amarillo , A . Dans. "Sudden unexplained death during sleep occurred commonly in the general population in the Philippines: a sub study of the National Nutrition and Health Survey .". Journal of Clinical Epidemiology 60 (6): 561–571. http://linkinghub.elsevier.com/retrieve/pii/S0895435606004082. Retrieved 2008-12-09. 
  5. ^ Ramos, Maximo D. (1971). Creatures of Philippine Lower Mythology. Philippines: University of the Philippines Press. 
  6. ^ a b Munger, Ronald G.; Elizabeth A. Booton (1998). "Bangungut in Manila: sudden and unexplained death in sleep of adult Filipinos". International Journal of Epidemiology 27 (4): 677–684. doi:10.1093/ije/27.4.677. PMID 9758125. http://ije.oxfordjournals.org/content/27/4/677.full.pdf. Retrieved 2011-07-29. 
  7. ^ http://www.inq7.net/lif/2004/jun/19/lif_7-1.htm (link broken as of 3 October 2007).
  8. ^ Munger RG (1987). "Sudden death in sleep of Laotian-Hmong refugees in Thailand: a case-control study". Am J Public Health 77 (9): 1187–90. doi:10.2105/AJPH.77.9.1187. 
  9. ^ a b Tatsanavivat P, Chiravatkul A, Klungboonkrong V, Chaisiri S, Jarerntanyaruk L, Munger RG, Saowakontha S (1992). "Sudden and unexplained deaths in sleep (Laitai) of young men in rural northeastern Thailand". Int J Epidemiol 21 (5): 904–10. doi:10.1093/ije/21.5.904. PMID 1468851. 
  10. ^ Tungsanga K, Sriboonlue P (1993). "Sudden unexplained death syndrome in north-east Thailand". Int J Epidemiol 22 (1): 81–7. doi:10.1093/ije/22.1.81. PMID 8449651. 
  11. ^ Nademanee K, Veerakul G, Nimmannit S, et al. (1997). "Arrhythmogenic marker for the sudden unexplained death syndrome in Thai men". Circulation 96 (8): 2595–2600. PMID 9355899. 
  12. ^ Vatta M, Dumaine R, Varghese G, et al (February 2002). "Genetic and biophysical basis of sudden unexplained nocturnal death syndrome (SUNDS), a disease allelic to Brugada syndrome". Hum. Mol. Genet. 11 (3): 337–45. doi:10.1093/hmg/11.3.337. PMID 11823453. http://hmg.oxfordjournals.org/cgi/pmidlookup?view=long&pmid=11823453. 
  13. ^ Kirschner RH, Eckner FA, Baron RC (1986). "The cardiac pathology of sudden, unexplained nocturnal death in Southeast Asian refugees". JAMA 256 (19): 2700–5. doi:10.1001/jama.256.19.2700. PMID 3773176. 
  14. ^ Munger RG, Prineas RJ, Crow RS, Changbumrung S, Keane V, Wangsuphachart V, Jones MP (1991). "Prolonged QT interval and risk of sudden death in South-East Asian men". Lancet 338 (8762): 280–1. doi:10.1016/0140-6736(91)90419-P. PMID 1677112. 
  15. ^ Munger RG, Booton EA (1990). "Thiamine and sudden death in sleep of South-East Asian refugees". Lancet 335 (8698): 1154–5. doi:10.1016/0140-6736(90)91154-3. PMID 1971884. 
  16. ^ a b Nademanee K, Veerakul G, Mower M, et al. (2003). "Defibrillator Versus beta-Blockers for Unexplained Death in Thailand (DEBUT): a randomized clinical trial". Circulation 107 (17): 2221–6. doi:10.1161/01.CIR.0000066319.56234.C8. PMID 12695290. 
  17. ^ a b Adler SR (1995). "Refugee stress and folk belief: Hmong sudden deaths". Soc Sci Med 40 (12): 1623–9. doi:10.1016/0277-9536(94)00347-V. PMID 7660175. 
  18. ^ Munger RG, Booton EA (1998). "Bangungut in Manila: sudden and unexplained death in sleep of adult Filipinos". Int J Epidemiol 27 (4): 677–84. doi:10.1093/ije/27.4.677. PMID 9758125. 
  19. ^ Himmunngan P, Sangwatanaroj S, Petmitr S, Viroonudomphol D, Siriyong P, Patmasiriwat P (March 2006). "HLa-class II (DRB & DQB1) in Thai sudden unexplained death syndrome (Thai SUDS) families (Lai-Tai families)". Southeast Asian J. Trop. Med. Public Health 37 (2): 357–65. PMID 17124999. 
  20. ^ Gotoh K (1976). "A histopathological study on the conduction system of the so-called "Pokkuri disease" (sudden unexpected cardiac death of unknown origin in Japan". Jpn Circ J 40 (7): 753–68. PMID 966364. 

Further reading