Sleep problems are linked to a worsening of suicidal thoughts in high-risk young adults, regardless of the severity of their depression, according to a new study led by Stanford University School of Medicine. The association is particularly strong among young people with a high degree of variability in bedtimes and wake-up times.
“Suicide is the tragic outcome of psychiatric illness interacting with multiple biological, psychological, and social risk factors,” said lead author Rebecca Bernert, Ph.D., Stanford assistant professor of psychiatry and behavioral sciences, and suicidologist.
“Sleep disturbances stand apart from other risk factors because they are visible as a warning sign, yet nonstigmatizing and highly treatable. This is why we believe they may represent an important treatment target in suicide prevention.”
Although sleep disturbances have been studied as a risk factor for suicide, this study is the first to objectively investigate disturbed sleep as a short-term indicator of risk in young adults.
The researchers gathered both objective and self-reported sleep characteristics among 50 high-risk young people (aged 18-23). The participants, who were chosen from nearly 5,000 undergraduate students enrolled in a university research pool, had a history of suicide attempts or recent suicidal ideation (thoughts of suicide).
For one week, the participants wore watch-like devices containing an accelerometer to measure their wrist movements while asleep or trying to sleep. The device had been previously validated as an accurate way to distinguish sleep-wake patterns and generate a variety of sleep metrics.
At the start of the study, and seven and 21 days later, subjects also completed questionnaires to determine the severity of their suicidal symptoms, insomnia, nightmares, depression, and alcohol use.
Those with a high degree of variability in when they fell asleep for the night and when they awoke in the morning were more likely to experience suicidal symptoms at the seven- and 21-day marks, the researchers found. Falling asleep at very different times each night was especially predictive of an increase in suicidal symptoms, they said.
The association remained even when researchers controlled for the severity of participants’ depression, substance use, and the severity of their suicidal symptoms at the start of the study.
Participants with a lot of variation in their bedtimes also reported more insomnia and nightmares, which themselves independently predicted more suicidal behaviors.
“Insomnia and nightmares beget more variability in when we are able to then fall asleep on subsequent nights, which speaks to the way in which insomnia develops,” Bernert said.
“Sleep is a barometer of our well-being, and directly impacts how we feel the next day. We believe poor sleep may fail to provide an emotional respite during times of distress, impacting how we regulate our mood, and thereby lowering the threshold for suicidal behaviors.”
Bernert said sleep disturbances and suicidal ideation are both symptoms of depression, making it critical to disentangle these relationships and evaluate factors that stand alone to predict risk.
The researchers are also conducting two suicide-prevention clinical trials to test the efficacy of a brief, non-medication insomnia treatment for suicidal behaviors.
“Treatments tested for suicidal behaviors are alarmingly scarce in comparison with need and remain mismatched to the acute nature of a suicidal crisis,” she said.
“Compared to other risk factors for suicide, disturbed sleep is modifiable and highly treatable using brief, fast-acting interventions. Because sleep is something we universally experience, and we may be more willing to openly talk about it relative to our mental health, we believe its study may represent an important opportunity for suicide prevention.”
The findings are published in the Journal of Clinical Psychiatry.