(Reuters Health) - People with restless legs syndrome may be more likely to think about suicide or to actually make plans to take their own lives, compared to people without the troublesome condition, a new study suggests.

Typically, people with restless legs syndrome say that when they’re lying down, “they have a creepy-crawly feeling in their legs plus an irresistible urge to move,” explained study coauthor Dr. Brian Koo, an associate professor of neurology at the Yale Medical School. “That urge to move prevents them from staying in bed.”

And that often means that patients with restless legs syndrome can’t get a good night’s sleep. It’s entirely possible that the poor sleep is leading to depression and suicidality, Koo said.

Koo’s team can’t say for sure that the syndrome causes people to think about suicide; they can only say there’s a correlation, according to the report published in Sleep Medicine.

The take home message from the study, Koo said, is that “restless legs syndrome is associated with very serious psychiatric consequences, including thoughts of suicide and/or attempts at suicide.”

Restless legs syndrome is relatively common, affecting up to three percent of U.S. adults, the researchers noted.

To look more closely on the psychological impact of the syndrome, Koo and his colleagues recruited 192 patients and a comparison group of 158 people without restless legs. The study volunteers ranged in age from 18 to 89.

Both groups filled out questionnaires on the syndrome, sleep, depression and suicidal thoughts and behavior. They were also queried about a host of demographic and health factors.

Even after accounting for depression and other factors, the researchers found that people with restless leg syndrome were 2.8 times more likely to have experienced suicidal ideation or behavior. Their odds of suicidality increased if their restless legs syndrome was severe or very severe or if they also suffered from depression.

While the study only shows an association, Koo suspects that restless legs syndrome causes suicidality. “Having treated hundreds of patients I think it is causing depression and likely the suicidality,” he said. “Whether it works through a mechanism of sleep loss or something else I don’t know.”

The new study “is consistent with literature showing various types of sleep disturbances are associated with suicidality,” said Peter Franzen, an assistant professor in the department of psychiatry at the University of Pittsburgh. “We see it with all kinds of sleep complaints, including people with insomnia, short sleep, and long sleep. This is showing it’s also true with restless leg syndrome.”

And that’s not surprising, said Franzen, who was not involved with the new research. “People with disrupted sleep don’t function as well,” he explained. “Sleep is important when it comes to regulating emotions. And there are cognitive deficits when you don’t get good sleep. You have trouble with decision making and you’re more apt to make impulsive decisions.”

SOURCE: bit.ly/2OrKHCd Sleep Medicine, online October 11, 2018.