“This study bolsters the argument that a lack of sleep can cause depression,” said study author James Gangwisch, an assistant professor of psychiatry at Columbia University Medical Center in New York City. “Teens with earlier parental-mandated bedtimes were less likely to suffer from depression and suicidal thoughts.”

Gangwisch was to present the findings Tuesday at the Associated Professional Sleep Societies annual meeting, in Seattle.

The study stemmed from data on more than 15,000 adolescents who participated in the National Longitudinal Study of Adolescent Health.

The researchers found that 1,143 of the teens were depressed and 2,038 had suicidal ideation, the term clinicians use to describe suicidal thinking. Dr. Jonathan Pletcher, an adolescent medicine specialist from Children’s Hospital of Pittsburgh, pointed out that suicidal thoughts are common in teenagers, which is why the study included more teens with suicidal thoughts than depressed adolescents.

“A lot of teens have suicidal thoughts, but there’s a big difference between suicidal ideation and being suicidal,” Pletcher said.

When Gangwisch and his research team looked at the relationship of depression and suicidal thoughts to parental-mandated bedtimes, they found a clear correlation.

Teens whose parents insist on 10 p.m. or sooner for lights out were 25 percent less likely to be depressed and 20 percent less likely to have suicidal thoughts, compared with kids who hit the sack at midnight or later.

Gangwisch said he adjusted the data to account for numerous factors, including parental connectedness and the age of the teens, because older teens probably would have later bedtimes. After controlling for these factors, he said, it was clear that a lack of sleep was to blame for the increased risk of depression and suicidal thoughts.

“Kids that have to go to bed earlier are getting more sleep,” he said.

Pletcher said it’s likely that a combination of factors accounted for the increased risk. “There’s a bi-directional relationship between depression and sleep,” he said. “Teens who get less sleep may be more anxious and more likely to feel badly. But, I think this study’s findings also speak to a connection between the teen and their parents and their ability to work together.”

Forbes has more Information on Depression

For people with a history of depression or bipolar disorder, the risk of relapse looms like a cloud over their lives, threatening to separate them from their work, relationships, even their children. Stress, sleep deprivation, hormonal shifts, and stopping treatment are among the most common relapse triggers.

Signs – Symptoms of Depression:

* Depressed people usually possess the following characteristics.

* Persistent sad mood
* Difficulty in concentration and unusual forgetfulness
* Slowness in actions and thinking
* Extreme pessimism and feeling of worthlessness
* Suicidal thoughts
* Feeling of not being loved by anybody and life has no meaning
* Low drive or motivation
* Unexplained feeling of fatigue
* Rapid gain or loss of body weight and inability to experience appetite
* Sleep disturbances mainly during early morning hours
* Palpitation
* Disturbances in the stomach
* Intolerance to sound
* Increased sensitivity and unexplained feelings of guilt.

The National Mental Health Information Center at the U.S. Department of Health and Human Services lists numerous triggers. Here are five:
• Interpersonal friction
• Feeling overwhelmed or having too much to do
• Being judged or criticized
• Ending a relationship
• Physical illness

Sometimes the signs of dangerous stress are more subtle. Laura Gilmartin, 38, an office manager in Skokie, Ill., finds herself eating more junk food or smoking more than usual. “Or if I find myself coming home from work and falling into bed more than two days in a row, that gets me scared. The more time I want to spend in bed the more I know I need to get out of bed.”

Delay decisions during relapse

The temptation to stop treatment on your own is another trigger, one that can lead to a downward spiral. Mary, 45, of Western Massachusetts, almost landed in the hospital during a suicidal depressive episode when she decided to go cold turkey. “What happens is I begin to feel great, and I rationalize that less is better when it comes to medication,” she says.

If you are in the midst of a relapse, it’s critical to realize that your outlook on everything is altered, and it’s unlikely that you will be aware of your lack of perspective. “So to the extent possible, important decisions should be delayed,” says Richard Raskin, PhD, a licensed psychologist in New York City.

Lisa, 42, a real estate broker in Huntington, N.Y., has been battling depression for years and can now steel herself against relapses. During the past year, she and her husband separated, and though she felt sad, she used the tools she learned in therapy to keep perspective. “I wasn’t depressed. I think that’s a testament of what talk therapy and medication can do. Ten years ago that would have put me in the grave.”

Guide for this: Health