Sleep problems in young teenagers may signal an increased risk of suicidal thoughts and self-harm attempts later in adolescence, a new study suggests.

Teens who had trouble sleeping at ages 12 to 14 were about two-and-a-half times more likely to have suicidal thoughts at ages 15 to 17, said study researcher Maria Wong, associate professor of psychology at Idaho State University.

"Parents, teachers and physicians know [sleep is] important, but underestimate how it could be a risk factor for many things if adolescents don't sleep well," Wong told MyHealthNewsDaily.

The study found that sleep and suicidal thoughts were associated, not that one causes the other, Wong said. But the evidence does suggest sleep problems are a good predictor for developing suicide or depression risk later on, she said.

The study was published this month in the Journal of Psychiatric Research.

Surveying the risk

Wong and her colleagues surveyed the sleep habits of 280 boys and 112 girls from families with a high-risk for alcoholism, and a matching group of boys and girls who didn't come from high-risk families. They surveyed the boys and girls when they were between ages 12 and 14, and asked questions such as "Did you have trouble sleeping during the last six months?" and "Have you had nightmares in this time period?"

When researchers followed up three years later, they found that teens who reported trouble sleeping when they were 12 to 14 years old were 2.44 times more likely to have suicidal thoughts when they were 15 to 17 years old than teens who didn't have sleeping problems.

And teens who reported trouble sleeping at ages 12 to 14 were four times more likely to exhibit suicidal behavior or to have harmed themselves at ages 15 to 17 than teens who didn't have sleeping problems, the study said.

Even after controlling for risk factors such as gender, parental alcoholism and parental suicidal thoughts, sleep was the one factor that seemed to indicate later suicidal risks, the researchers said.

Explaining the relationship

Though the researchers didn't directly examine ways to explain the association between sleep and suicidal thoughts , Wong said one reason might be sleep's effect on impulse control.

Past research has shown that sleep deprivation leads to increases in impulsive behavior less planning and more acting based on whims, she said. Therefore, people who have trouble sleeping may be less likely to inhibit certain behaviors than people who sleep well, and those behaviors could lead to depression or suicidal tendencies.

Another possible link lies in the brain's development, Wong said. During adolescence, the prefrontal lobe, which controls functions like planning and goal-setting, develops the most rapidly. Lack of sleep or restless sleep could affect the development of this part of the brain, she said.

The relationship between sleep problems and suicidal thoughts is likely bidirectional meaning, one influences the other, said James Gangwisch, a psychiatry professor at Columbia University in New York, who was not involved with the study.

"Sleep problems are a symptom of depression, so there's a question of if the sleep problems come before the suicidal [thoughts], or is it a symptom of depression," Gangwisch told MyHealthNewsDaily. Not sleeping well might cause some to become depressed, and therefore have suicidal thoughts, he said.

Gangwisch found a similar relationship between sleep and depression in a 2010 study in the journal Sleep. That study showed that middle schoolers and high schoolers who weren't required to be in bed before midnight were 42 percent more likely to be depressed than teens with a bedtime of 10 p.m. or earlier.

Parents, health professionals and teachers can use the findings of the new study to help teens who may be at risk for depression or suicidal thoughts, Wong said.

"Kids might have trouble talking about suicidal thoughts or depression, but it's easier to talk to them about a physical issue because they don't think of it as 'it's my problem,'" she said.

Pass it on: Young teens with trouble sleeping have an increased risk of suicidal thoughts later in adolescence.

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