More US adults sleepwalk, at least occasionally, than previously thought, according to findings of a study reported today in Neurology. The study, described by researchers as the first to use a large, representative sample of the US general population to gauge how common the condition is among adults in the United States, also found that sleepwalking is more common among individuals with depression and obsessive-compulsive disorder.
Researchers surveyed 15 929 adults aged 18 to 102 years in 15 states to gather information on their mental health, medical history, and medication use. Participants also were asked specific questions related to sleepwalking. Nearly 3 in 10 respondents reported sleepwalking at some time in their lives, and 3.6% reported at least 1 sleepwalking episode in the previous year. An earlier study in the European general population suggested that 2% of adult Europeans had sleepwalked in the previous year. The only previous findings on prevalence of sleepwalking among US adults, a 1979 study of 1000 adults in Los Angeles, had found a prevalence of 2.5%.
More than 80% of those who sleepwalked reported doing so for more than 5 years. Individuals with certain conditions (obstructive sleep apnea syndrome, circadian rhythm sleep disorder, insomnia disorder, alcohol abuse/dependence, major depressive disorder, obsessive-compulsive disorder) were at higher risk of frequent sleepwalking episodes, defined as occurring 2 or more times a month. The greater sleepwalking risk among those with major depressive disorder and obsessive-compulsive disorder was not related to the use of psychotropic medications, the researchers found.
Use of over-the-counter sleeping pills was also associated with a higher risk of frequent sleepwalking episodes. In addition, the researchers found an increased risk of sleepwalking among individuals who used selective serotonin reuptake inhibitor antidepressants (SSRIs), but only among those with a history of night-time wanderings.
The researchers also found that sleepwalking was equally likely to occur in men and women, and that it seemed to decrease with age. Nearly one-third of those sleepwalking had a family history of the disorder.
Maurice Ohayon, MD, DSc, PhD, lead author and professor of psychiatry and behavioral science, Stanford University School of Medicine in California, said in a release the associations between certain factors and sleepwalking are intriguing. “There is no doubt an association between nocturnal wanderings and certain conditions, but we don’t know the direction of the causality,” he said. “Are the medical conditions provoking sleepwalking, or is it vice versa? Or perhaps it’s the treatment that is responsible.”