Sleepwalking Is More Common Than Previously Imagined
May 15, 2012

Sleepwalking Is More Common Than Previously Imagined

A California psychiatrist has released a study, published in the journal Neurology, that suggests sleepwalking may be more common than previously thought. “The numbers are very big,” says researcher Maurice Ohayon, MD, PhD, DSc, professor of psychiatry and behavioral sciences and director of the Stanford University School of Medicine.

It is thought that medication use and certain psychological and psychiatric conditions can trigger sleepwalking, but the exact causes are unknown, writes Louise Chang, MD for WebMD. It is not fully known how widespread the problem is, however.

Wandering around at night can be harmless and is often played for laughs on television, but sleepwalking can have serious consequences. Episodes can result in injuries to the wanderer or others and lead to impaired psychosocial functioning.

Studies on the number of sleepwalkers are sparse, Ohayon tells WebMD. In one of the few studies done in adults and published 30 years ago, past researchers found 2.5 percent sleepwalked. “There are nearly no data regarding the prevalence of nocturnal wanderings in the adult general population. In the United States, the only prevalence rate was published 30 years ago.”

For this study, the first to use a large, representative sample of the US general population to demonstrate the number of sleepwalkers, the researchers also aimed to evaluate the importance of medication use and mental disorders associated with sleepwalking. Ohayon and his colleagues secured a sample of 19,136 individuals from 15 states and then used phone surveys to gather information on participants´ mental health, medical history and medication use.

Participants were asked specific questions related to sleepwalking, including frequency of episodes during sleep, duration of the sleep disorder and any inappropriate or potentially dangerous behaviors during sleep.

Those who didn´t report any episodes in the last year were asked if they had sleepwalked during their childhood. Participants were also queried about whether there was a family history of sleepwalking and whether they had other parasomnia symptoms, such as sleep terrors and violent behaviors during sleep.

Certain medical conditions, Ohayon found, were linked to sleepwalking. Sleep apnea, in which people have abnormal pauses in breathing during the night, was a primary factor. Along with insomnia, alcohol abuse or dependence, depression and obsessive-compulsive disorder were also significant factors.

People taking antidepressants known as SSRIs had more than twice the odds of sleepwalking, Ohayon says. SSRIs include drugs such as Celexa, Lexapro, Paxil, Prozac, and Zoloft. Those on over-the-counter sleeping pills boosted risk, too. “You have a two and a half times higher chance of sleepwalking if you are taking an over-the-counter sleeping pill with diphenhydramine,” he says.

“I´m not too surprised by the results,” Timothy Young, a neurologist and sleep medicine specialist with the Mayo Clinic Health System in Eau Claire, Wisconsin, told Andrew M. Seaman of Reuters.

Young, who was not involved in the research, said that sleepwalking is thought to be common during childhood, but tapers off as people get older, writes Seaman. Young said it becomes a problem when people start walking down stairs or outside.

Ohayon said although more research is needed, the work could help raise awareness of the association among primary care physicians, writes By Hannah Furness for The Telegraph. “We´re not expecting them to diagnose sleepwalking, but they might detect symptoms that could be indices of sleepwalking.”

The study was partially funded by the US National Institutes of health, the Arrillaga Foundation, the Bing Foundation and Neurocrines Biosciences, which is a biopharmaceutical company.