Drinking and Psychological Trauma Increase Risk of REM Sleep Behavior Disorder
The cause of rapid eye movement (REM) sleep behavior disorder, a condition in which people violently act out their dreams by flailing their arms or making running motions, is unknown, but it has been associated with neurodegenerative disorders, such as Parkinson's disease, dementia with Lewy body, and multiple system atrophy. Now, a study published online in Neurology on December 26 has identified alcohol use and psychological distress as risk factors.
Identifying Risk Factors
In their analysis, researchers from McGill University in Montreal observed 30,097 people ages 45 to 85 (mean age 63) from the Canadian Longitudinal Study on Aging (CLSA), a national study that collects biological, medical, psychological, social, lifestyle, and economic information from participants.
The researchers conducted in-person interviews about lifestyle, behavior, social, economic, and psychological factors and screened them for various health conditions, including REM sleep behavior disorder.
Of the 19,584 participants ultimately considered for the analysis, 3.2 percent were diagnosed with REM sleep behavior disorder.
Risk Factors Linked to Sleep Disorder
Based on the in-person interviews and a questionnaire about REM sleep behavior disorder, researchers noted that people with possible REM sleep disorder were more likely to be moderate to heavy drinkers (18.9 percent versus 14.3 percent), current smokers (8.9 percent vs 6.4 percent), and past smokers (42.7 percent vs 36.9 percent) than those without the disorder.
They also used antidepressants more frequently (13.4 percent vs 6.2 percent), scored higher on a psychological distress scale (15.2 vs 13.9), and were likely to report at least moderate psychological distress (10.9 percent vs 6.6 percent).
In addition, patients were more likely to be diagnosed with mental illness (34.9 percent vs 21.9 percent) with a higher incidence of anxiety (13.8 percent vs 7.3 percent) and depressive disorder (20.7 percent vs 13.9 percent). They also were more likely to test positive for posttraumatic stress disorder (10.5 percent vs 4.0 percent).
Other risk factors included being male (59 percent of people with the disorder were men vs 42 percent women) and having a lower level of education (13.2 years vs 13.6 years) and income.
Further Research Is Needed
The researchers emphasized that although these risk factors may contribute to possible REM sleep behavior disorder, the study did not prove that they are the cause.
As for the mental health connection, the researchers hypothesized that sleep disorders may be a symptom of mental illness. It could also be that REM sleep behavior disorder leads to psychological distress by disrupting sleep and disturbing bed partner relations.
Researchers will continue to observe the participants to determine how many go on to develop Parkinson's disease.