Melatonin appears to reduce self-harming behavior among young people

Sleep treatment with melatonin appears to lead to young people with self-harming behavior reducing their self-harming behavior, according to a Swedish study.
“If you sleep well, you make better decisions,” says Sarah Bergen, one of the researchers behind the study.

Melatonin is a hormone that controls sleep and wakefulness. It is the most common medication among children and young people with sleep difficulties. In Sweden, its use has increased significantly in recent years.

Since many of those who are prescribed melatonin have some form of psychiatric diagnosis, researchers at the Karolinska Institute in Stockholm wanted to find out whether the treatment affects self-harming behavior in children and young people.

“Previous studies have looked at how other drugs, such as antidepressants, affect the risk of self-harming behavior, but no one has investigated the effect of melatonin in the same thorough way,” says Sarah Bergen, a researcher in medical epidemiology at the Karolinska Institute and the study’s lead author.

Big difference

A total of around 25,500 individuals between the ages of 6 and 18 who had been prescribed melatonin were included in the study. Of these, 87 percent had at least one psychiatric diagnosis such as ADHD, anxiety, or depression.

When the researchers compared the incidence of self-harming behavior in the same individuals before and after they were prescribed melatonin, they saw a difference. The risk of self-harm increased before melatonin was prescribed and decreased in the months after treatment began, especially in girls. Since the individuals were compared with themselves, the researchers were able to control for background factors that could influence the correlations, such as genetics, the severity of sleep problems, or psychiatric diagnoses.

For example, the risk of girls intentionally poisoning themselves decreased by half in the first months after melatonin treatment compared to the period before.

“We cannot say that it is melatonin that reduces the risk of self-harming behavior; it may be that the patients also received other treatment, such as behavioral therapy, that we are not aware of, but it points to a connection,” says Sarah Bergen.

Without antidepressants

Some of the study participants had also been prescribed antidepressants. But even when the researchers removed them from the analysis, the results remained the same. This suggests that melatonin could have a positive effect on the risk.

“It’s simply that everyone makes better decisions when they sleep better. It’s about what you eat, how you perform at school, and probably even whether you choose to harm yourself or not,” says Sarah Bergen.

Among the self-harm behaviors that occurred, 57 percent involved some form of poisoning and 34 percent involved cuts. The data from the study comes from the years 2006 to 2013.

The study has been published in The Journal of Child Psychology and Psychiatry. Two of the researchers behind the study are employed by the pharmaceutical company Johnson & Johnson.