WEDNESDAY, April 1, 2009 (HealthDay News) -- New research provides more evidence of a link between sleeplessness and suicidal thoughts or attempts, although it's not clear whether insomnia actually makes people want to kill themselves.
Still, the findings suggest that "persistent sleep problems might be an important contributor to suicidal thinking," said study author Dr. Marcin Wojnar, a research fellow at the University of Michigan and an associate professor of psychiatry at the University of Warsaw in Poland.
Researchers have connected insomnia to suicide before. But the new study, said to be the most comprehensive of its kind, looks at the population as a whole, not mentally ill people in particular.
The findings were to be released Wednesday at the World Psychiatric Association International Congress on Treatments in Psychiatry in Florence, Italy. The study was funded by the U.S. Department of Veterans Affairs, the U.S. National Institute on Drug Abuse, the U.S. National Institute on Alcohol Abuse and Alcoholism and the U.S. National Institute of Mental Health.
The researchers looked at the results of a national survey of 5,692 adults taken between 2001 and 2003.
Overall, about a third of those surveyed reported sleep problems, but only a small number said they'd been suicidal.
Fewer than 3 percent reported thinking about suicide in the previous year. Fewer than 1 percent said they'd planned suicide, and the number was nearly the same for those who had attempted it.
People who had trouble getting to sleep were 5.1 times more likely than those who didn't to have had thoughts about suicide. They were also 9.1 times more likely to have planned suicide and 7.5 times more likely to have attempted suicide within the past 12 months.
Other kinds of sleeplessness -- waking up too early and having trouble sleeping through the night -- were also linked to suicidal thoughts and attempts.
The links remained even when researchers adjusted their figures to account for the influence of mental illness and chronic health conditions.
Wojnar acknowledged that the study didn't take into account the timing of sleeplessness to determine whether it came before suicidal thoughts or attempts. The study also didnt look at people who committed suicide, nor did it prove a cause-and-effect relationship between suicide and insomnia.
Mental-health experts estimate that many more people -- perhaps 10 to 40 times more -- try to commit suicide than actually kill themselves. However, suicide is still a huge problem, taking an estimated 877,000 lives a year, according to the World Health Organization.
Research links anxiety to trouble falling asleep and difficulty sleeping through the night, while early awakening is connected to depression, said Alan Berman, executive director of the American Association of Suicidology.
"For people who are suffering from insomnia over some period of time, it affects all aspects of daily functioning -- the ability to think clearly, to focus and problem solve and synthesize information and make decisions," he said.
Also, insomnia "basically lowers the threshold for impulsive behavior and for being reactive to an emotional event."
What to do? Step in and try to resolve the problem, Berman said. "Effective intervention is really important," he said. "Insomnia is something we can observe. People know about it when they're experiencing it and can respond to it."
Learn more about suicide from the U.S. National Institutes of Health.