Sleep paralysis in the elderly

Isolated sleep paralysis, known as 'ghost oppression' in Hong Kong, is common among Chinese elderly over age 70. In a sample of 158 subjects, nearly 18% reported experiences of ghost oppression, with descriptions closely matching sleep paralysis. Onset showed a clear bimodal distribution, with peaks in adolescence and after age 60; at least one-third of cases began late in life. Those with ghost oppression also reported more frequent nocturnal sleep disturbances, consistent with the REM/wakefulness dissociation hypothesis. A family history was reported in 10% of subjects.

Study at a glance

Abstract

SummaryIsolated sleep paralysis (SP) is a common sleep phenomenon that is highly colored by indigenous beliefs. In Hong Kong Chinese, the ‘ghost oppression phenomenon’ (GO) has been shown to be descriptively identical to SP. The prevailing concept is that the majority of cases with SP have their onset during adolescence, but the lack of any systematic study on an older population means that late‐onset cases can not be excluded. In a study investigating the prevalence of mental disorders in Chinese elderly aged above 70 y in Hong Kong, we employed the revised GO questionnaire to study the prevalence of SP in this group of elderly as well. One hundred and fifty‐eight subjects were finally analyzed for the study. Almost 18% (95% C.I. 11.77%, 23.68%) of the subjects reported experiences of GO. Their description of the features of GO showed striking similarity to those of SP. There was a clear bimodal distribution of onset of GO with peaks during adolescence and after age 60 y. At least one‐third of the cases were late onset. In concordance with the rapid eye movement (REM)/wakefulness dissociation hypothesis of SP, those elderly with GO+ experiences also had more frequent nocturnal sleep disturbances. A family history was reported in 10% of subjects.