Researchers of a new study have identified risk factors for a disruptive and sometimes violent sleep disorder known as rapid eye movement (REM) sleep behavior disorder.

Rem Sleep Behavior Disorder

Individuals with REM sleep behavior disorder physically act out vivid, and often unpleasant dreams with vocal sounds and violent arm and leg movement during REM. People do not normally move during REM sleep, which helps keep them from acting out their dreams.

In people with REM sleep behavior disorder, however, something goes wrong with the system that's supposed to paralyze people during sleep. Thus, they may act out a violent or action-filled dream by yelling, punching, and kicking, sometimes to the point of harming themselves or their sleep partner.

Because sufferers of the condition can become violent, some have even used a diagnosis of the disorder to explain violent crimes in court. The onset of REM sleep behavior disorder is usually gradual but it can get worse with time.

Who Are At Risk Of Violent Sleep Disorder?

In a new study, researchers identified factors that could increase a person's risk for the disorder. After looking at the data of more than 30,000 individuals, researchers found that those taking antidepressants for depressions, and those diagnosed with post-traumatic stress disorder have increased risk.

Researchers also found that those with the disorder were twice as likely to have a mental illness. They also have 1.5 times the odds of having psychological distress.

Men were twice as likely to have the disorder. Sufferers of REM sleep behavior disorder were also more likely to be moderate to heavy drinkers, have slightly less education, have lower income and more likely to have smoked.

Rem Sleep Behavior Disorder And Neurodegenerative Diseases

Researchers said that REM sleep behavior disorder could be an indicator of a future neurodegenerative disease such as Parkinson's disease and dementia. The findings may have implications in research that seek to prevent neurologic conditions.

"Identifying lifestyle and personal risk factors linked to this sleep disorder may lead to finding ways to reduce the chances of developing it," said study researcher Ronald Postuma, from McGill University in Montreal, Canada.

"Our hope is that our findings will help guide future research, especially because REM sleep behavior disorder is such a strong sign of future neurodegenerative disease."

The findings were published in Neurology on Dec. 26.