Nearly 8% of patients referred to a sleep disorders clinic reported they had initiated or taken part in sexual behavior while sleeping. Men accounted for 75% of the self-reported sexsomniacs.
"We were surprised at how common it was," said study author Sharon A. Chung, a staff scientist in the Sleep Research Laboratory at the University Health Network in Toronto. "We thought we'd get just a handful of people, yet it was almost one in twelve."
In the study, researchers asked 832 patients about sexual behavior while sleeping, which can range from masturbation to intercourse. About 11% of men and 4% of women said they had engaged in "sleep sex" or sexsomnia.
Researchers said the prevalence is probably lower in the general population.
Sexomnia, or Sleep Sex, a legitimate medical disorder. Sexsomnia is a form of a sleep disorder called parasomnia. Parasomnia is any unwanted behavior that occurs during sleep.
"An act of parasomnia can be as small as opening your eyes while fast asleep or grinding your teeth, to getting up and vacuuming, speaking, eating or having sex," according to Chung.
Generally, people have no awareness of what they are doing and no recollection of parasomnia.
People experiencing a parasomnia are not often violent; they usually pose more of a threat to themselves, said Dr. Lisa Shives, medical director of Northshore Sleep Medicine in Evanston, Ill. But there are rare cases in which people have killed someone and claimed they were sleeping and unaware of their actions.
What brings on sexsomnia isn't really understood, but about twice as many patients who reported sexsomnia had used illegal drugs (15.9% vs. 7.7%) and were more likely to have consumed alcohol (41% vs. 27%). People who had experienced sexsomnia reported problems with depression, fatigue, and insomnia (falling or staying asleep), although no more so than other patients at the sleep clinic. Rates of smoking and caffeine consumption were also similar, according to the study.
The good news is that parasomnia, sexsomnia included, is treatable with medications including benzodiazepines, such as clonazepam, which is also used to treat epilepsy and anxiety disorders, Shives said.
Yet few sexomnia patients bring the issue up with the doctors. In the sleeping disorder study, only four said they had previously told a medical professional about sexsomnia.
"Of the thousands of patients I've seen, I've never had someone come in complaining of sexsomnia, but I have always believed it's a bona fide disorder," Shives said. "It's a form of sleep walking. When people are sleep walking, they may do any rote or instinctual behavior. That can include walking, eating, driving and sexual activity."
The reason patients don't bring it up could be embarrassment, the fact that doctors rarely ask aboutsexomnia, or that sexomnia patients aren't particularly bothered by sexomnia, said Chung.
"Is it [sexsomnia] a problem? As long as you don't get into legal problems and as long as your partner doesn't mind, it's [sexsomnia] not a problem," Chung said. "Although it [sexsomnia] can leave you tired the next day."
SOURCES: Sharon A. Chung, Ph.D., staff scientist, Sleep Research Laboratory, Department of Psychiatry, University Health Network, Toronto; Lisa Shives, M.D., medical director, Northshore Sleep Medicine, Evanston, Ill.; June 7, 2010, presentation, SLEEP 2010, San AntonioWikipedia: A sleep disorder, or somnipathy, is a medical disorder of the sleep patterns of a person or animal. →