More evidence linking insomnia to depression

There are a number of reasons why sleep is important to good health. Now, researchers in Japan have discovered that if you struggle with a good night’s sleep, you are twice as likely to suffer from depression as those who do slumber through the night.

After surveying thousands adults in rural Japan over two years, they discovered that people with insomnia at the study’s beginning were two and a half times more likely to have new or ongoing depression by the end of the study.

“The study is interesting because it confirms again that there is a connection between sleep abnormalities and depression,” said Dr. Srinivasan Pillay, an assistant clinical professor of psychiatry at Harvard Medical School. “What it does not tell us is whether sleep abnormalities are the cause of depression of something else. It tells us there is an association between the two.”

There is a growing body of evidence and speculation that there is a connection between insomnia and depression. Dr. Yichi Inoue in the Department of Somnology at Tokyo Medical University set out to see whether it held true over time in a Japanese population. About 20% of the Japanese population suffers from insomnia. They suspected there was a connection between this and the number of cases of anxiety, depression and substance abuse.

In 2005 they sent surveys to 3000 Japanese adults in the same town. The surveys were meant to detect sleep quality and state of mental health. They were asked to repeat the survey two years later in 2007.

Poor sleep quality raised depression risk by 60% and disturbed sleep raised depression risk by 30%. Difficulty falling asleep or the need for sleep medication rose the risk to 20% over those who slept well.

While the study may not show a causal relationship, it is clear that if there is trouble falling asleep or maintaining healthy sleep, there is a risk of mental health compromise. Early treatment for the sleep dysfunction is important to long term health.

Source: Reuter