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Sudden Unexpected Nocturnal Death Syndrome

Sudden Unexpected Nocturnal Death Syndrome

Since 1977 more than a hundred Southeast Asian immigrants in the United States have died from the mysterious disorder known as sudden unexpected nocturnal death syndrome (SUNDS). SUNDS had an unusually high incidence among recently relocated Laotian Hmong refugees. All but one of the victims were men, the median age was thirty-three, all were apparently healthy, and all died during their sleep. Despite numerous studies of SUNDS, which have taken into account such varied factors as toxicology, heart disease, sleep apnea and other sleep disorders, genetics, metabolism, and nutrition, medical scientists have not been able to determine its exact cause. Medical opinion appears to favor an impairment of the electrical pathways and specialized muscle fibers that contract the heart. It is widely held, however, that some type of intense stressor is likely an additional risk factor.

The medical folklorist Shelley Adler postulates that a supernormal nocturnal experience that is part of Hmong traditional beliefs can trigger the fatal syndrome. The experience is referred to as a "night-mare," not in the modern sense of a bad dream, but rather in its original denotation as the nocturnal visit of an evil being that threatens to press the very life out of its terrified victim. Hmong refugees in the United States experience a culture-specific manifestation of the universal nightmare phenomenon. The Hmong Nightmare (known as dab tsog ) causes cataclysmic psychological stress, which can trigger sudden death. Although the Dab Tsog attack in Laos is related to the worldwide nightmare tradition, the peculiar stresses of Hmong refugee experience transformed its outcome. The power of traditional belief in the nightmarein the context of the trauma of war, migration, rapid acculturation, and inability to practice traditional healing and ritualcauses cataclysmic psychological stress to male Hmong refugees that can result in SUNDS.

See also: Causes of Death


Adler, Shelley R. "Ethnomedical Pathogenesis and Hmong Immigrants' Sudden Nocturnal Deaths." Culture, Medicine and Psychiatry 18 (1994):2359.

Hufford, David J. The Terror That Comes in the Night. Philadelphia: University of Pennsylvania Press, 1982.

Parrish, R. Gibson, Myra Tucker, Roy Ing, Carol Encarnacion, and Mark Eberhardt. "Sudden Unexplained Death Syndrome in Southeast Asian Refugees: A Review of CDC Surveillance." Morbidity and Mortality Weekly Review 36 (1987):4353.


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