Sleep Medicine
October 1, 2022
M M Ohayon, A H Pakpour
Sleep paralysis (SP) is common in the US general population. In a longitudinal study of 12,218 adults initially interviewed and 10,931 re-interviewed three years later, 9.7% reported at least one SP episode in the previous year at baseline, and 15.1% reported SP at follow-up. The 1-year incidence was 2.7%. About 30% of those with SP at baseline still had episodes three years later. Predictors of persistent SP included age, race, major depressive disorder, pain, hypersomnolence, cataplexy, hypnagogic and hypnopompic hallucinations, posttraumatic stress disorder, reduced sleep duration by at least 60 minutes, and use of analgesic/antipyretic medication. Incident SP had similar predictors.
Psychiatry Research
December 27, 2000
M M Ohayon
Hallucinatory experiences are reported by 38.7% of the general population across the UK, Germany, and Italy, based on telephone surveys of 13,057 people aged 15 or older. Most hallucinations occur at sleep onset (hypnagogic, 24.8%) or upon awakening (hypnopompic, 6.6%) and are unrelated to a specific pathology in over half of cases. Daytime hallucinations, reported by 27% of the sample, include visual (3.2%) and auditory (0.6%) types strongly linked to psychotic disorders (odds ratios of 6.6 and 5.1, respectively) and anxiety (odds ratios of 5.0 and 9.1). Haptic hallucinations (3.1%) are most associated with current drug use (odds ratio 9.8). Daytime visual and auditory hallucinations indicate a greater risk of psychiatric disorders, while other daytime sensory hallucinations relate more to organic or toxic conditions.
Neurology
April 12, 1999
M M Ohayon, J Zulley, C Guilleminault et al.
About 6.2% of the general population in Germany and Italy has experienced at least one episode of sleep paralysis, with 0.8% experiencing severe episodes (at least one per week). Sleep paralysis is less common than earlier small-sample studies suggested. The condition is often linked to mental disorders; users of anxiolytic medication were nearly five times as likely to report sleep paralysis, even after accounting for mental and sleep disorders. Other predictive factors include automatic behavior, bipolar disorders, physical disease, hypnopompic hallucinations, nonrestorative sleep, and nocturnal leg cramps.
The British journal of psychiatry : the journal of mental science
October 1, 1996
M M Ohayon, R G Priest, M Caulet et al.
In a representative UK community sample of 4,972 people aged 15-100 interviewed by telephone, 37% reported hypnagogic hallucinations (occurring when falling asleep) and 12.5% reported hypnopompic hallucinations (occurring when waking up). Both types were more common among those with insomnia, excessive daytime sleepiness, or mental disorders. The prevalence of narcolepsy in the UK was 0.04%. Hypnagogic and hypnopompic hallucinations were much more common than expected, far exceeding what narcolepsy alone can explain. Hypnopompic hallucinations may be a better indicator of narcolepsy in people reporting excessive daytime sleepiness.