Late nights may make teenagers more prone to depression and suicidal thoughts by depriving them of sleep, according to a study by researchers at Columbia University.
Teens whose parents let them go to bed past midnight were 24 percent more likely to be depressed and 20 percent more likely to have contemplated suicide than peers whose parents set bedtimes at or before 10 p.m., the researchers said yesterday in the journal Sleep. Earlier set bedtimes may be protective because they increase the likelihood of getting enough sleep, they said. The study is the first to show that sleep deprivation may cause depression and suicidal thoughts in adolescents. Previous research has shown a link, though the relationship was not clear because insomnia can be a symptom of depression.
“Our results strengthen the argument that lack of sleep can cause depression as opposed to simply being a symptom of depression,’’ James Gangwisch, the study’s lead author and an assistant professor at the university’s medical center, said in an e-mail. “Adequate quality sleep could therefore be a preventative measure against depression and a treatment for depression.’’
About 4,400 Americans between the ages of 10 and 24 commit suicide each year, according to the Centers for Disease Control and Prevention.
Gangwisch and colleagues studied data from 15,659 US students, who were in grades seven to 12 between 1994 and 1996, and their parents. Seven percent of the teens were found to have depression and 13 percent said they seriously contemplated suicide during the preceding 12 months.
